Abstracts
Diflubenzuron
CAS No. 35367-38-5
For more abstracts search PubMed or Toxnet
 
 

ACTIVITY: Insecticide, Acaricide, Chemosterilant (Benzoylurea)

CAS Name: N-[[(4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide

Structure::

Reports available from
The National Technical Information Service
(NTIS)

Order from NTIS by: phone at 1-800-553-NTIS (U.S. customers); (703)605-6000 (other countries); fax at (703)605-6900; and email at orders@ntis.gov. NTIS is located at 5285 Port Royal Road, Springfield, VA, 22161, USA.
Order No. Title Keywords/Abstract

NTIS/PB94-120136

43 pages

1994 - Diflubenzuron Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review.

Authors: Patuxent Wildlife Research Center, Laurel, MD.

Toxic hazards
Insecticides
Natural resources management
Dimilin
Diflubenzuron

NTIS/PB94-180734

118 pages

1993 - Pilot Monitoring Project for 14 Pesticides in Maryland Surface Waters.

Authors: Kroll RB, Murphy DL
- Environmental Protection Agency, Annapolis, MD. Chesapeake Bay Program.
- Maryland Dept. of the Environment, Baltimore. Water Management Div.

A pilot pesticide monitoring project was conducted by the Maryland Department of the Environment (MDE) during calendar year 1992. Surface waters from three regions of the State were monitored for the presence of 14 pesticides. The list of analytes was compiled from the results of a risk screening effort by MDE, a collaborative project with the U.S. Fish and Wildlife Service and recommendations from the Chesapeake Bay Program Toxics Sub-Committee, Alachlor, adrin, atrazine, carbofuran, chlordane, chlorpyrifos, cyanazine, dieldrin, diflubenzuron, fenvalerate, metolachlor, permethrin, simazine, and toxaphene were the 14 pesticides on the analyte list.

NTIS/OTS0571681

[EPA/OTS; Doc #88-920010285]

INITIAL SUBMISSION: ACUTE TOXICITY OF UC 54012 25WP
(N-[[(4-
CHLOROPHENYL)AMINO]-
CARBONYL]-2,6-
DIFLUOROBENZAMIDE) TO DAPHNIA MAGNA WITH COVER LETTER DATED
10-07-92
UNION CARBIDE CORP
N-[[(4-CHLOROPHENYL)AMINO]-CARBONYL]-2,6-
DIFLUOROBENZAMIDE
ENVIRONMENTAL EFFECTS
ACUTE TOXICITY
INVERTEBRATES

NTIS/OTS0571772

[EPA/OTS; Doc #88-920010461]

INITIAL SUBMISSION: ACUTE TOXICITY OF UC 54012 (N-[[(4-
CHLOROPHENYL)AMINO]-
CARBONYL]-2,6-
DIFLUOROBENZAMIDE) TO MYSID SHRIMP (MYSIDOPSIS BAHIA) WITH COVER LETTER DATED
10-06-92
UNION CARBIDE CORP
N-[[(4-CHLOROPHENYL)AMINO]-CARBONYL]-2,6-
DIFLUOROBENZAMIDE
ENVIRONMENTAL EFFECTS
ACUTE TOXICITY
INVERTEBRATES

NTIS/OTS0540511

[EPA/OTS; Doc #88-920004163]

INITIAL SUBMISSION: ORAL LETHAL DOSE TOXICITY TEST WITH INX-1179-289 IN RATS WITH COVER LETTER DATED 06-15-92 AND ATTACHMENTS E I DUPONT DE NEMOURS & CO
INX-1179-289
HEALTH EFFECTS
ACUTE TOXICITY
MAMMALS
RATS
ORAL
GAVAGE

NTIS/MIC-93-02794

44 p

1993 - Persistance and degradation of diflubenzuron in conifer foliage, forest litter and soil, following simulated aerial application.

Author: Sundaram KMS

Forest Pest Management Inst., Sault Sainte Marie (Ontario).


Conifers
Dimilin
Diflubenzuron

NTIS/PB89-226724

578 p

1989 - Pesticide Background Statements. Volume 4. Insecticides.

Authors: Boberschmidt L, Saari S, Sassaman J, Skinner L

MITRE Corp., McLean, VA.

The individual Insecticide Background Statements have been compiled to provide a comprehensive review of the available information concerning the use, chemistry, toxicology, environmental fate, and comparative hazard in forest applications. It is not within the scope of the Insecticide Background Statements to critically evaluate and/or independently analyze the raw data from which conclusions were reached in the various studies and reports examined in preparing the background statements contained in the document. References to the published literature at the end of each background statement are provided for those individuals who wish to independently evaluate the toxicological data and environmental fate information that is presented in summary form. In many instances, secondary sources, such as review articles, handbooks, and company technical data sheets, were used. Insecticides included in the report are: acephate, bacillus thuringiensis, carbaryl, and diflubenzuron. Final rept.

NTIS/PB88-239397

36p

1987 - Fiscal Year 1987 Program Report: Maryland Water Resources Research Center,

Author: Menzer RE
Maryland Water Resources Research Center, College Park.

The report represents four projects supported in 1987. They dealt with the question of whether nitrogen or phosphorus is the more important contributor to decline of submerged aquatic vegetation in the Chesapeake Bay, the dynamics of inorganic nitrogen in the Choptank River, the use of beryllium-10 as a sediment tracing mechanism in the Chesapeake Bay, and the long term effects of the insecticide diflubenzuron on stream metabolism.

NTIS/PB87-193058

8p

1987 - Pesticide Fact Sheet Number 68.1: Diflubenzuron.

Environmental Protection Agency, Office of Pesticide Programs.


Pesticides
Diflubenzuron
Toxic substances

NTIS/PB87-111951

8p

1987 - Pesticide Fact Sheet Number 68: Diflubenzuron.

Environmental Protection Agency, Office of Pesticide Programs.


Pesticides
Toxic substances
Diflubenzuron

NTIS/PB84-177476

11p

1984 - Acute and Chronic Effects of Diflubenzuron (Dimilin) on Freshwater Fish and Invertebrates.

Authors: Nebeker AV, McKinney P, Cairns MA

Corvallis Environmental Research Lab., OR.

Toxicology
Dimilin
Diflubenzuron

NTIS/NTN83-0166

1 p

1983 - Insect Growth Regulator May Be Used For Cancer Treatment.

Department of Agriculture, Washington, DC.

Abstract: This citation summarizes a one-page announcement of technology available for utilization. A chemical currently used to control insects could possibly be used to treat cancer. Diflubenzuron, or Dimilin, as the chemical is commonly called, has not only stoped the growth of melanoma tumors in mice, but has actually reduced tumor size as much as 22 percent in 24 hours... Diflubenzuron has extremely low mamalian toxicity. Dimilinis currently used to control many kinds of insects, including the boll weevil. It is not a pesticide or poison, but a growth regulator that interferes with the insects' bodies. The chemical's action probably affects membrane permeability. Dimilin prevents the uptake of nucleosides which are the building blocks of nucleic acids. The chemical apparently interferes with tumor growth by making cell membranes in the tumor less ...

NTIS/PB83-157560

18p

1982 - Ability of Standard Toxicity Tests to Predict the Effects of the Insecticide Diflubenzuron on Laboratory Stream Communities.

Authors: Hansen SR, Garton RR

Corvallis Environmental Research Lab., OR.


Toxicology
Bioassay
Insecticides
Water pollution effects(Animals)
Dimilin

NTIS/PB86-230315

8p

1982 - Synthesis of Haptens and Potential Radioligands and Development of Antibodies to Insect Growth Regulators Diflubenzuron and BAY SIR 8514.

Authors: Wie SI, Sylwester AP, Wing KD, Hammock BD

California Univ., Davis.


Chemical analysis
Growth regulators
Insects
Diflubenzuron

NTIS/PB83-220582

45p

1982 - Effect of Hormonal Pollutants on Aquatic Crustacea and the Surrounding Environment.

Author: Laufer H

Connecticut Univ., Storrs. Inst. of Water Resources.

The impact of administering compounds which have hormonal activity on insects was evaluated on crustacea. The Juvenile Hormone Analog (JHA) Methoprene and its formulation, Altosid, were tested as were other compounds with specific insecticidal effects, such as Insect Growth Regulators (IGRs). Lethal levels of Methoprene (Altosid) were established. Sublethal levels affect reproduction and embryonic development. Safe concentrations of Methoprene and Precocene were found. Dimilin was more toxic to Daphnia than to target insects. To provide new means for studying aspects of crustacean reproduction and its control, we have initiated short term organ culture procedures. Conditions for cultivating fragments of Carcinus meanas hepatopancreas were established. This tissue is capable of synthesizing yolk protein precursors, vitellogenins. Interstitial cells of the hepatopancreas were identified as the source of vitellogenins by the use of immunocytological localization.

NTIS PB Rep. PB80-177,868

18 pp

1980 - Selected toxicological studies of Dimilin in weanling male rats.

Excerpt: " ... Dimilin, at 15, 150, and 300 mg/kg/day, transiently depresses the testosterone in plasma in the prepubertal period, yet has no delaying effects on the development of the reproductive organs."

NTIS/PB82-261389

12p

1981 - The Effects of Diflubenzuron on a Complex Laboratory Stream Community.

Authors: Hansen SR, Garton RR

Corvallis Environmental Research Lab., OR.


Toxicology
Insecticides
Dimilin
Water pollution effects(Animals)

NTIS/PB80-177041

6p

1979 - Effect of Diflubenzuron on an Estuarine Crustacean

Authors: Nimmo DR, Hamaker TL,
Moore JC, Sommers CA

Environmental Research Lab., Gulf Breeze, FL.

Crustacea
Pesticides
Toxicology
Toxic substances
Dimilin

 

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16786494&query_hl=1&itool=pubmed_docsum

Pest Manag Sci. 2006 Aug;62(8):752-8.

Hazards and uptake of chitin synthesis inhibitors in bumblebees Bombus terrestris.

Mommaerts V, Sterk G, Smagghe G.

Department of Biology, Faculty of Sciences, Free University of Brussels, Brussels, Belgium.

This research project examined the potential hazards of a major class of insect growth regulators (IGRs) to survival, reproduction and larval growth in bumblebees Bombus terrestris L. Eight chitin synthesis inhibitors (CSIs) were tested: buprofezin, cyromazine, diflubenzuron, flucycloxuron, flufenoxuron, lufenuron, novaluron and teflubenzuron. These different IGRs, which are important in the control of pest insects in greenhouses, were applied via three different routes of exposure under laboratory conditions: dermal contact, and orally via the drinking of sugar/water and via pollen. The compounds were tested at their respective maximum field recommended concentrations (MFRC) and also in dose-response assays to calculate LC(50) values. In general, none of the CSIs showed acute worker toxicity. However, there was a dramatic reduction in brood production, especially after oral treatment with pollen and sugar/water. Conspicuously, egg fertility was reduced in all treatments with diflubenzuron and teflubenzuron. In addition to egg mortality, the worker bumblebees removed larvae from the treated nest, and in most cases these individuals were dead first-second instars. Under a binocular microscope, such larvae showed an abnormally formed cuticle leading to mechanical weakness and death. In another series of experiments using (14)C-diflubenzuron and (14)C-flufenoxuron, cuticular penetration in workers was studied for a better understanding of the differences in toxicity. With (14)C-diflubenzuron, transovarial transport and accumulation in the deposited eggs supported the strong reproductive effects. Overall, the present results suggest that CSIs should be applied with caution in combination with bumblebees. The compatibility of each compound to be used in combination with B. terrestris is discussed in relation to calculated LC(50) values, routes of uptake and effects.

PMID: 16786494 [PubMed - indexed for MEDLINE]

NOTE from FAN: 6 of the 8 pesticides tested are fluorinated: diflubenzuron, flucycloxuron, flufenoxuron, lufenuron, novaluron and teflubenzuron


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15582210

Food Chem Toxicol. 2005 Jan;43(1):173-83.
 
CYP superfamily perturbation by diflubenzuron or acephate in different tissues of CD1 mice.

Sapone A, Pozzetti L, Canistro D, Broccoli M, Bronzetti G, Potenza G, Affatato A, Biagi GL, Cantelli-Forti G, Paolini M.

Department of Pharmacology, Molecular Toxicology Unit, Alma-Mater Studiorum, University of Bologna, Via Irnerio, 48, 40126 Bologna, Italy.

This work aimed to investigate whether the insecticide acephate (125 or 250mg/kg b.w.) or diflubenzuron (752 or 1075mg/kg b.w.), two of the most widely used pesticides worldwide, impairs CYP-linked murine metabolism in liver, kidney and lung microsomes after repeated (daily, for three consecutive days) i.p. administration. The regio- and stereo-selective hydroxylation of testosterone was used as multibiomarker of different CYP isoforms. Both gender and tissue specific effects were observed. Lung was the most responsive tissue to induction by lower diflubenzuron dose, as exemplified by the marked increase of testosterone 7alpha-hydroxylation (CYP2A) (up to 13-fold) in males. Higher dose produced a generalized inactivation. At the lower dose acephate induced 6beta- (CYP3A1/2, liver) as well as 2beta- (CYP2B1/2, kidney) hydroxylase activities ( approximately 5 and approximately 4-fold increase, respectively) in males. In females, a marked suppression of the various hydroxylations was observed. At 250mg/kg of acephate, animals did not survive. Induction of the most affected isoforms was sustained by immunoblotting analysis. Corresponding human CYP modulations might disrupt normal physiological functions related to these enzymes. Furthermore, the co-mutagenic and promoting potential of these pesticides, phenomena linked to CYP upregulation (e.g. increased bioactivation of ubiquitous pollutants and generation of oxygen free radicals) are of concern for a more complete definition of their overall toxicological potential.

EXCERPTS:
... Diflubenzuron was found to induce murine CYP3A1/2 (activating, for example, aflatoxins and nitropyrenes) in lung (both sexes) and kidney (for females only), as exemplified by the increase 6B and 2B hydroxylations of testosterone. Inductions were also recorded for CYP2B1/2 (activating olefins and halogenated hydrocarbons) in lung (both sexes) and kidney (for female mice only), as shown by the enhancement of testosterone 6a, 16a, 16B and 2B hydroxylases. In the lung, induction in the 7a position (linked to CYP2A, responsible for metabolizing nitrosamines, and specific compounds such as esamethyl phospamide and butadiene) was registered for both sexes. A generalized induction was seen in the lung. Simultaneously, a marked reduction of testosterone metabolism in the liver (both sexes), kidney (6? and 16? hydroxylations, females) and lung (6a, 16a, 16B and 2B positions, males) was observed.

... In summary, our results demonstrated the induction and suppression properties of diflubenzuron and acephate. With the increased bioactivating potential toward ubiquitous environmental pollutants the induction generates large amounts of oxygen free radicals acting at all levels of multistep carcinogenesis (Paolini et al., 1999). Our observations are in line with previous data on diflubenzuron or acephate’s abilities to induce positive foci in Balb/c3T3 cells in an in vitro cell transformation model (medium-term test, 6–8 weeks) (Perocco et al., 1993 and Perocco et al., 1996) as well as with the co-carcinogenicity potential of acephate found in the rat (Paolini et al., 1997). Notwithstanding diflubenzuron is negative in in vivo long-term carcinogenicity studies, its co-mutagenic potential may be of concern in the presence of ubiquitous premutagens (e.g. diet, environmental pollutants). Furthermore, the ability of these insecticides to act as homeostatic disruptors should not be underestimated.

PMID: 15582210 [PubMed - in process]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10799337

Toxicol Appl Pharmacol. 2000 May 1;164(3):273-9.
 
Diflubenzuron, a benzoyl-urea insecticide, is a potent inhibitor of TCDD-induced CYP1A1 expression in HepG2 cells.

Ledirac N, Delescluse C, Lesca P, Piechocki MP, Hines RN, de Sousa G, Pralavorio M, Rahmani R.

Laboratoire de Pharmaco-Toxicologie Cellulaire et Moleculaire, INRA, Antibes, 06606, France.

Diflubenzuron (DFB) belongs to a group of compounds called benzoyphenyl ureas acting as chitin synthesis inhibitors, which also inhibit growth of B16 murine melanomas. The present study was designed to investigate the effect of this insecticide, on CYP1A1 expression and induction in human hepatoma cells HepG2. Treatment of HepG2 cells over 72 h with noncytotoxic concentrations of DFB resulted in a strong dose-dependent decrease in constitutive ethoxyresorufin-O-deethylase activity. Moreover, DFB significantly decreased CYP1A1 induction by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) after 24 h exposure, as demonstrated by ethoxyresorufin-O-deethylase (EROD) activity and Northern blot analysis. Additional studies were performed both on parental HepG2 cells and HepG2-241c.1, which were stably transfected with the chloramphenicol acetyltransferase (CAT) reporter gene, cloned under the control of the human CYP1A1 promoter (-1140 to +59). Ribonuclease protection assays (RPA) analysis clearly demonstrated an inhibition of CYP1A1 transcription in both cell lines. Surprisingly, in corresponding experiments using 3-methylcholanthrene (3-MC) as a CYP1A1 inducer, DFB was less effective. Finally, in competitive binding studies using a 9S-enriched fraction of HepG2 cytosol, DFB was capable of displacing [(3)H]-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) from its Ah receptor binding site. Taken together, these results support the involvement of a transcriptional mechanism in the inhibition of CYP1A1 expression in HepG2 cells by DFB, possibly via an Ah receptor antagonism. Copyright 2000 Academic Press.

PMID: 10799337 [PubMed - indexed for MEDLINE]

EXCERPT:

4. Conclusions
Several conclusions could be drawn from these studies:
(1) the induction of cytochromes P4501A1 appeared to be much more sensitive than cytotoxicity test for determining the biological effects of pesticides;
(2) there are significant differences between the cell types and the derivative. Indeed, carbaryl was shown to be an inducer in all cell types, whereas cypermethrin and tetrachlorvinphos are inducers only in hepatocytes. DFU and TCV are inducers in hepatocytes, but inhibitors in HepG2 and HaCaT cells;
(3) significant interspecies variability exists concerning induction which seems more important in rat than in human cells;
(4) finally, there is no direct interaction of the tested insecticides with the Ah receptor, which would imply, either a AhR-independent activation of CYP1A1 by these or metabolites formation which in turns follows the classical AhR transduction pathway. However, a number of questions remain yet unanswered:—what is the origin of the inter-tissue or inter-species differences?—is there a relationships between enzyme induction, and toxicity?—what are specific enzymes involved in pesticides metabolism in mammals?—are there chemical interactions between pesticides and other environmental pollutants?…
On the whole, although insecticides concentrations in the human diet are very low, the results suggest that care should be taken because of possible risk stemming from the exposure to insecticides, given the well established pharmaco-toxicological importance of CYPs induction.


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=13129788

Food Addit Contam. 2003 Aug;20(8):716-9.
 
Occurrence of pesticide residues in mushrooms in Northern Ireland, July 1997-January 1999.

Mitchell SH, Kilpatrick M.

Department of Agriculture and Rural Development for Northern Ireland, Belfast, UK. samuel.mitchell@dardni.gov.uk

The results of surveillance monitoring for pesticides in mushrooms obtained from wholesale cooperatives in Northern Ireland between 1997 and 1999 are presented. Samples (n = 145) were analysed for up to 11 pesticides, resulting in 1575 pesticide/crop combinations. Fifty-five (38%) samples did not contain detectable residues, with 90 (62%) samples containing residues above their respective detection limits. Residues (carbendazim) above the maximum residue level were found in two (<2%) samples. The most frequently detected residues were diflubenzuron and carbendazim present in 47 (32%) and 38 (26%) samples, respectively. There was no significant seasonality in the distribution of the residues.

PMID: 13129788 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15149123

Commun Agric Appl Biol Sci. 2003;68(4 Pt A):299-305.

Laboratory evaluation of dimilin on growth and glutathione activity in mosquitofish, a non-target species

Draredja-Beldi H, Soltani N.

Laboratoire de Biologie Animale Appliquee, Departement de Biologie, Faculte des Sciences, Universite d'Annaba, 23000 Annaba, Algerie.

Recently, dimilin was found to be effective on Culex pipiens (Diptera: Culicidae). Although considerable research has evaluated the efficacy of diflubenzuron, a benzoylphenylurea derivative, against target pest populations, impacts of this compound on nontarget organisms are comparatively unknown. Therefore, this study evaluate toxicity of dimilin (25% W.P), a trade formulation of diflubenzuron, on a larvivorous non-target species, Gambusia affinis (Pisces, Poeciliidae). The compound, applied for 24h at a concentration of 78 ng/l corresponding to the LD90 obtained against the fourth instar larvae of C. pipiens, was first tested on growth and development of G. Affinis by measuring some morphometric indexes. Results showed that dimilin caused a significant (p<0.01) reduction in both the length and the weight of juveniles. It had no significant effect on the gonadosomatic index and the condition index (K) measured in adult females. A significant reduction in hepatosomatic index was only observed at day 30 during the exposure. In addition, the body level of glutathione was also determined in order to provide information on their toxicity. Treatment resulted in a significant reduction in both the amount of ovarian proteins and the level of body glutathione starting day 15 compared to controls of the same age.

PMID: 15149123 [PubMed - indexed for MEDLINE]

 

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11874045

Sci Total Environ. 2002 Feb 21;285(1-3):237-45.

The stability and persistence of diflubenzuron in marine sediments studied under laboratory conditions and the dispersion to the sediment under a fish farm following medication.

Selvik A, Hansen PK, Ervik A, Samuelsen OB.

Institute of Marine Research, Department of Aquaculture, Bergen, Norway.

A high performance liquid chromatographic (HPLC) method was developed to determine the concentration of diflubenzuron, a delousing agent used in fish farming, in marine mud and shell sand. The recovery of diflubenzuron from mud was 100.8+/-1.1% and 105.5+/-4.3% for shell sand. The limit of quantitation was found to be 0.1 microg g(-1). The stability of diflubenzuron was studied under laboratory conditions in marine sediments at different temperatures (4 and 14 degrees C). No degradation of diflubenzuron occurred in the organic rich mud sediment or in the shell sand sediment during the experimental period of 204 days. Increasing the temperature from 4 to 14 degrees C had no effect on the stability. Furthermore, diflubenzuron showed to be persistent in both mud and shell sand sediment since no detectable diffusion from the sediment to the water phase occurred during the experimental period of 204 days. Increasing the water current in the tanks had no effect on the persistence. Under field conditions, the concentrations of diflubenzuron found in the organic material from sediment traps placed 2 m from the bottom under the cage in a fish farm during medication were high and ranged from 71 to 259 microg g(-1). The concentrations of diflubenzuron in the sediment under the fish farm were, however, low, with a maximum concentration of 5.4 microg g(-1). The dispersion of diflubenzuron to the sediment was limited to less than 20 m from the edge of the cage in every direction. Fifteen months following the medication, only traces (< 0.1 microg g(-1)) of diflubenzuron were detected in the sediment under the fish farm. Possible explanations for this decrease are resuspension and redistribution of sediment and/or oxic degradation of the drug.

PMID: 11874045 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=14653311

Toxicol Ind Health. 2002 Jun;18(5):225-35.
 
Effects of common-use pesticides on developmental and reproductive processes in Daphnia.

Kashian DR, Dodson SI.

Department of Fisheries and Wildlife Biology, Colorado State University, Fort Collins, CO 80523-1474, USA. dkashian@cnr.colostate.edu

Daphnia magna were evaluated for use as a screen for pesticides that have been demonstrated to have estrogenic (o'p'-DDT, di-n-butyl phthalate, toxaphene), anti-androgenic (p'p-DDE, linuron), thyroid (acetochlor, alachlor, metribuzin), insulin (amitraz) or lutenizing hormone (2,4-D) activity in vertebrates, and to establish daphnid sensitivity to these compounds. Pesticides with unknown effects on vertebrate endocrine systems (chlorosulfuran, cyanazine, diflubenzuron, metolachlor, and diquat) were also evaluated. Compounds were assayed for six days at environmentally relevant concentrations ranging from 0.001 to 100 mirog/L, using female Daphnia and their offspring. Sublethal endpoints included offspring sex (sex determination), clutch size (fecundity), and adult size (growth rate). Toxaphene was the only compound that affected sexual differentiation, increasing male production. Daphnia fecundity declined with exposure to toxaphene, and daphnid growth rates were reduced by acetochlor exposure. Diflubenzuron, o'p'-DDT, and p'p-DDE significantly reduced Daphnia survival. No correlation existed between affected reproductive or developmental processes and specific endocrine systems or subsystems. Results from this study indicate that Daphnia make a good screen for assessing potential environmental impacts but are not a useful indicator of pesticide hormonal activity in vertebrates. This assay consistently detected sublethal but ecologically relevant effects of these pesticides on Daphnia at environmentally relevant concentrations typically below their listed EC50 value.

PMID: 14653311 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11783663

Environ Sci Technol. 2001 Sep 15;35(18):3804-8.

Persistence of the insecticide Dimilin 45 ODC on conifer forest foliage in an Atlantic-climate ecosystem.

Rodriguez E, Barrio RJ, Goicolea A, Peche R, Gomez de Balugera Z, Sampedro C.

Department of Chemical and Environmental Engineering, School of Technical Engineering, University of the Basque Country, Vitoria-Gasteiz, Spain. iaproure@vc.ehu.es

The oil formulation of diflubenzuron (Dimilin 45 ODC) persisted for 10-12 weeks on the foliage of a conifer forest in an Atlantic-climate ecosystem. Within 22-30 days following treatment, 55-80% of the insecticide had been removed from the foliage. During this period, the concentration of diflubenzuron was higher than 370 ng g(-1). Aerial application at 56.3 g of Al ha(-1) resulted in deposition levels of the insecticide ranging from 867.5 to 1824.4 ng g(-1), depending upon forest characteristics. The results showed that aerial application is only a suitable technique for the treatment of forest areas with dense foliage and/or high tree density and no more than 15% of tree-free area. The only metabolite detected was 2,6-difluorobenzamide, and this persisted on foliage until the first rainfalls occurred. An empirical mathematical correlation was found to express the influence of meteorological variables--rainfall, solar radiation and temperature--on the persistence of the insecticide. These results suggested that degradation of diflubenzuron on foliage could be due to photodegradation. Some recommendations were made to optimize the deposition of the insecticide on foliage and to minimize its persistence and the off-site spray drift.

PMID: 11783663 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11417653

J AOAC Int. 2001 May-Jun;84(3):901-9.

Determination of five pesticide residues in oranges by matrix solid-phase dispersion and liquid chromatography to estimate daily intake of consumers.

Valenzuela AI, Pico Y, Font G.

Universitat de Valencia, Laboratori, de Toxicologia, Facultat de Farmacia, Burjassot, Spain.

Residues of benzoylphenylurea insecticides (diflubenzuron, hexaflumuron, and flufenuxuron), carboxamide acaricides (hexythiazox), and carbamate insecticides (benfuracarb) were determined in 150 orange fruit samples from September 1998 to June 1999, to estimate exposure of the Valencian population to oranges contaminated with these newly developed pesticides. The method for monitoring these residues is based on matrix solid-phase dispersion and liquid chromatography with UV or atmospheric pressure chemical ionization/mass spectrometry (APCI/MS) detection. Orange samples representing 11 varieties were collected from an agricultural cooperative and examined for the 5 pesticides. In 74.6% of all analyzed samples, the pesticide residues were below detection limits, which ranged from 0.002 to 0.05 mg/kg. Residues were detected in 25.4% of the samples, with higher incidences of diflubenzuron, flufenuxuron, hexythiazox, and benfuracarb; hexaflumuron residues were detected only occasionally. Two different pesticides exceeded maximum residue limits (MRLs) in 4 (2.7%) of the orange samples. Diflubenzuron surpassed 1 mg/kg MRL in 3 samples and flufenuxuron exceeded the 0.3 mg/kg MRL in 3 samples. The estimated daily intake of the 5 pesticide residues during the period was 0.077 microg/kg body weight per day. This value is much lower than the total admissible daily intake proposed by the Food and Agricultural Organization and the World Health Organization.

PMID: 11417653 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9763833

Ned Tijdschr Geneeskd. 1998 Jul 4;142(27):1567-9.

Comment in:
Ned Tijdschr Geneeskd. 1998 Nov 7;142(45):2488.

[A severe anaphylactic shock caused by spraying the oak processionary caterpillar (Thaumetopoea processionea) in North Brabant]

[Article in Dutch]

Bosma AH, Jans HW.

St. Joseph Ziekenhuis, afd. Cardiologie, Veldhoven.

The processionary caterpillar, Thaumetopoea processionea, caused much inconvenience in the Netherlands in 1996-1997; from the medical point of view, mostly itching and skin rash. After contact with stinging bristles of the caterpillar and with the pesticide Dimilin SC-48, of which diflubenzurone is the active agent, a 72-year-old man had to be resuscitated because of ventricular fibrillation caused by hypotension related to relative underfilling and low systemic vascular resistance. He made a good recovery. Such life-threatening situations can be prevented by publicly announcing plague control measures and closing of the affected areas to the population, with ample margins.

Publication Types:
• Case Reports

PMID: 9763833 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9595184

Bull Environ Contam Toxicol. 1998 May;60(5):702-8.

No abstract available
 
Implications for the use of diflubenzuron to reduce arthropod populations inhabiting evaporation ponds of the San Joaquin Valley, California.

McCasland CS, Cooper RJ, Barnum DA.

Department of Biology, University of Memphis, TN 38152, USA.

PMID: 9595184 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9002437

Arch Environ Contam Toxicol. 1997 Jan;32(1):69-79.
 
Virulence of the entomopathogenic fungus Metarhizium flavoviride Gams and Rozsypal and toxicity of diflubenzuron, fenitrothion-esfenvalerate and profenofos-cypermethrin to nontarget arthropods in Mauritania.

Peveling R, Demba SA.

Deutsche Gesellschaft fur Technische Zusammenarbeit (GTZ), Postfach 5180, 65726 Eschborn, Germany.

Within the framework of the GTZ project, Biological and Integrated Control of Locusts and Grasshoppers, a laboratory screening fo rMetarhizium flavoviride (strain Mfl 5) blastospore pathogenicity to the nontarget arthropods Pharoscymnus anchorago F. (Coleoptera:Coccinellidae), Trachyderma hispida (Forskal) (Coleoptera:Tenebrionidae), Palpares cf. tesselatus Rambur (Neuroptera:Myrmeleontidae) and Thanatus sp. (Araneae: Philodromidae) was conducted in Akjoujt research station, Mauritania. Various larval stages of desert locust, Schistocerca gregaria Forskal (Orthoptera:Acrididae), were tested as positive controls. The insect growth regulator diflubenzuron was used as a reference in the bioassay with P.anchorago. In addition, two organophosphate-pyrethroid insecticide swidely used in locust control, fenitrothion-esfenvalerate (P.anchorago, T. hispida) and profenofos-cypermethrin (Thanatussp.) were tested as toxic standards. M. flavoviride was not pathogenic to nontargets, but very virulent to S. gregaria. The results provided further evidence that the host range of M.flavoviride (Mfl5), a strain isolated from migratory locust in Madagascar, is very narrow. Diflubenzuron was toxic to P. anchorago and to S. gregaria. The LD50s of both chemical insecticides tested were considerably lower than the expected initial environmental concentration. The beneficial P. anchorago, a natural enemy of scale insects in date palms, was considered most at risk in the course of chemical locust control. The use of mycopesticides to control desert locust in date palm plantations offers an environmentally safe and economically viable alternative to chemical control.

PMID: 9002437 [PubMed - indexed for MEDLINE]


From Toxline at Toxnet

ENVIRONMENTAL SCIENCE & TECHNOLOGY; 31 (9). 1997. 2445-2454.

Fluorinated organics in the biosphere.

KEY BD, HOWELL RD, CRIDDLE CS

Dep. Civil Environ. Eng., Mich. State Univ., East Lansing, MI 48824, USA.

BIOSIS COPYRIGHT: BIOL ABS. The use of organofluorine compounds has increased throughout this century, and they are now ubiquitous environmental contaminants. Although generally viewed as recalcitrant because of their lack of chemical reactivity, many fluorinated organics are biologically active. Several questions surround their distribution, fate, and effects. Of particular interest is the fate of perfluoroalkyl substituents, such as the trifluoromethyl group. Most evidence to date suggest that such groups resist defluorination, yet they can confer significant biological activity. Certain volatile fluorinated compounds can be oxidized in the troposphere yielding nonvolatile compounds, such as trifluoroacetic acid. In addition, certain nonvolatile fluorinated compounds can be transformed in the biosphere to volatile compounds. Research is needed to assess the fate and effects of nonvolatile fluorinated organics, the fluorinated impurities present in commercial formulations, and the transformation

CAS Registry Numbers:
137938-95-5 - na
112839-33-5 - chlorazifop [C14H11Cl2NO4]
112839-32-4 - chlorazifop [ C14H11Cl2NO4]
106917-52-6 - flusulfamide [C13H7Cl2F3N2O4S]
104040-78-0 - flazasulfuron [C13H12F3N5O5S]
102130-93-8 - 4-Fluorothreonine [ C4-H8-F-N-O3 ]
101463-69-8 - flufenoxuron [C21H11ClF6N2O3]
101007-06-1 - acrinathrin [C26H21F6NO5]
97886-45-8 - dithiopyr [C15H16F5NO2S2]
96525-23-4 - flurtamone [C18H14F3NO2]
90035-08-8 - flocoumafen [C33H25F3O4]
88485-37-4 - fluxofenim [C12H11ClF3NO3]
85758-71-0 - 1-Decanol, 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heneicosafluoro- [ C10-H-F21-O ]
83164-33-4 - diflufenican [C19H11F5N2O2]
82657-04-3 - bifenthrin [C23H22ClF3O2]
81613-59-4 - flupropadine [C20H23F6N]

80164-94-9 - Methanone, phenyl((trifluoromethyl)phenyl)-, dichloro deriv. [ C14-H7-Cl2-F3-O ]
80020-41-3 - furyloxyfen [C17H13ClF3NO5]
79622-59-6 - fluazinam [C13H4Cl2F6N4O4]
79538-32-2 - tefluthrin [C17H14ClF7O2]
77501-63-4 - lactofen [C19H15ClF3NO7]
77501-60-1 - fluoroglycofen [C16H9ClF3NO7]
76674-21-0 - flutriafol [C16H13F2N3O]
72850-64-7 - flurazole [C12H7ClF3NO2S]
72178-02-0 - fomesafen [C15H10ClF3N2O6S]
71422-67-8 - chlorfluazuron [C20H9Cl3F5N3O3]

69806-34-4 - Haloxyfop
[C15H11ClF3NO4]
69335-91-7 - fluazifop [C15H12F3NO4]
68694-11-1 - Triflumizole [ C15-H15-Cl-F3-N3-O ]
68085-85-8 - cyhalothrin [C23H19ClF3NO3]
67485-29-4 - hydramethylnon [C25H24F6N4]
66332-96-5 - flutolanil [C17H16F3NO2]
64628-44-0 - triflumuron [C15H10ClF3N2O3]
63333-35-7 - bromethalin [C14H7Br3F3N3O4]
62924-70-3 - flumetralin [C16H12ClF4N3O4]
61213-25-0 - flurochloridone [C12H10Cl2F3NO]
59756-60-4 - fluridone [C19H14F3NO]

57041-67-5 - Desflurane [ C3-H2-F6-O ]
56425-91-3 - flurprimidol [C15H15F3N2O2]
55283-68-6 - ethalfluralin [C13H14F3N3O4]
53780-34-0 - mefluidide [C11H13F3N2O3S]
50594-66-6 - acifluorfen [C14H7ClF3NO5]
42874-03-3 - oxyfluorfen [C15H11ClF3NO4]

40856-07-3 - Difluoromethanesulphonic acid [ C-H2-F2-O3-S ]
37924-13-3 - perfluidone [C14H12F3NO4S2]
35367-38-5 - diflubenzuron [C14H9ClF2N2O2]
33245-39-5 - fluchloralin [C12H13ClF3N3O4]
31251-03-3 - fluotrimazole [C22H16F3N3]
29091-21-2 - prodiamine [C13H17F3N4O4]
29091-05-2 - dinitramine [C11H13F3N4O4]

28606-06-6 - na
28523-86-6 - Sevoflurane [ C4-H3-F7-O ]
27314-13-2 - norflurazon [C12H9ClF3N3O]
26675-46-7 - Isoflurane [ C3-H2-Cl-F5-O ]
26399-36-0 - profluralin [C14H16F3N3O4]
25366-23-8 - thiazafluron [C6H7F3N4OS]

24751-69-7 - Nucleocidin [ C10-H13-F-N6-O6-S ]
14477-72-6 - Acetic acid, trifluoro-, ion(1-) [ C2-F3-O2 ]
9002-84-0 - Polytetrafluoroethylene (Teflon) ( (C2-F4)mult- or (C2-F4)x-)
2837-89-0 - 1,1,1,2-Tetrafluoro-2-chloroethane (Freon 124) [ C2-H-Cl-F4 ]

2164-17-2 - fluometuron [C10H11F3N2O]
1861-40-1 - benfluralin [C13H16F3N3O4]
1827-97-0 - 2,2,2-Trifluoroethanesulfonic acid [ C2-H3-F3-O3-S ]
1763-23-1 - Perfluorooctane sulfonic acid [ C8-H-F17-O3-S ]
1717-00-6 - 1,1-Dichloro-1-fluoroethane [ C2-H3-Cl2-F ]

1582-09-8 - trifluralin [C13H16F3N3O4]
1493-13-6 - Trifluoromethanesulfonic acid [ C-H-F3-O3-S ]
811-97-2 - 1,1,1,2-Tetrafluoroethane (Norflurane) [ C2-H2-F4 ]
754-91-6 - Perfluorooctanesulfonamide [ C8-H2-F17-N-O2-S ]

640-19-7 - fluoroacetamide [C2H4FNO]
513-62-2 - Fluoroacetate [ C2-H2-F-O2 ]
453-13-4 - 1,3-Difluoro-2-propanol [ C3-H6-F2-O ]
420-46-2 - 1,1,1-Trifluoroethane [ C2-H3-F3 ]
406-90-6 - Fluroxene (Ethene, (2,2,2-trifluoroethoxy)-) [ C4-H5-F3-O ]

370-50-3 - flucofuron [C15H8Cl2F6N2O]
335-76-2 - Perfluorodecanoic acid [ C10-H-F19-O2 ]
335-67-1 - Perfluorooctanoic acid (PFOA) [ C8-H-F15-O2 ]
311-89-7 - Perfluorotributylamine [ C12-F27-N ]
306-83-2 - 2,2-Dichloro-1,1,1-trifluoroethane [Freon 123) [ C2-H-Cl2-F3 ]
151-67-7 - 2-Bromo-2-chloro-1,1,1-trifluoroethane (HALOTHANE) [ C2-H-Br-Cl-F3 ]
144-49-0 - Fluoroacetic acid [ C2-H3-F-O2 ]

116-14-3 - Tetrafluoroethylene [ C2-F4 ]
98-56-6 - 1-Chloro-4-(trifluoromethyl)benzene [ C7-H4-Cl-F3 ]
88-30-2 - TFM (3-Trifluoromethyl-4-nitrophenol)[ C7-H4-F3-N-O3 ]
79-38-9 - Chlorotrifluoroethylene [ C2-Cl-F3 ]
76-38-0 - Methoxyflurane [ C3-H4-Cl2-F2-O ]
76-15-3 - Chloropentafluoroethane (Freon 115 )[C2-Cl-F5 ]
76-14-2 - Dichlorotetrafluoroethane (Freon 114 )[ C2-Cl2-F4 ]
76-13-1 - 1,1,2-Trichloro-1,2,2-trifluoroethane (Freon 113 ) [C2-Cl3-F3 ]
76-05-1 - Trifluoroacetic acid [ C2-H-F3-O2]
75-71-8 - Dichlorodifluoromethane (Freon 12) [ C-Cl2-F2]

75-69-4 - Trichloromonofluoromethane ( Freon 11, 11A, 11B) [C-Cl3-F]
75-68-3 - 1-Chloro-1,1-difluoroethane (Freon 142, Freon 142b) [ C2-H3-Cl-F2]
75-45-6 - Chlorodifluoromethane (Freon 21) [ C-H-Cl-F2]

75-43-4 - Dichlorofluoromethane (Freon 21) [C-H-Cl2-F]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8661519

Arch Environ Contam Toxicol. 1996 May;30(4):444-51.

Effects of Diflubenzuron on Benthic Macroinvertebrates in Littoral Enclosures

O'Halloran SL, Liber K, Schmude KL, Corry TD.

Lake Superior Research Institute, University of Wisconsin-Superior, Superior, Wisconsin 54880, USA

Two applications of the insect growth regulator diflubenzuron were made to replicate littoral enclosures at nominal concentrations of 0.7, 2.5, 7.0, and 30 &mgr;g/L. Assessment of the effects of this insecticide on benthic macroinvertebrate community structure was accomplished by measuring changes in abundance and taxonomic richness. Chironomidae and Ephemeroptera were the most sensitive groups sampled, with no observed effect concentrations of 2.5 and 0.7 &mgr;g/L, respectively. No adverse effects were observed on Mollusca or Oligochaeta at any of the test concentrations. Taxonomic richness was noticably reduced at 7.0 and 30 &mgr;g/L on all post-application sampling dates, producing changes in community structure that persisted for >/=57 days.

PMID: 8661519 [PubMed - as supplied by publisher]


From Toxline at Toxnet

HRC JOURNAL OF HIGH RESOLUTION CHROMATOGRAPHY; 19 (2). 1996. 105-110.

HPLC-UV DETERMINATION OF PESTICIDE RESIDUES AT 0.01 PPM IN APPLE AND PEAR PULP USED FOR BABY FOOD

BICCHI C, BALBO C, BINELLO A, D'AMATO A

Abstract: BIOL ABS. RRM RESEARCH ARTICLE FOOD TOXICITY DIFLUBENZURON ETHIOFENCARB TEFLUBENZURON TRIFLUMURON TRIFORINE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY ANALYTICAL METHOD

CAS Registry Numbers:
• 99039-56-2 - N-(((3,5-Dichloro-2,4-difluorophenyl)amino)carbonyl)-2,6-difluorobenzamide
• 64628-44-0 - Triflumuron
35367-38-5 - Diflubenzuron
29973-13-5 - Ethiofencarb (Croneton)
26644-46-2 - Triforine
• = fluorinated


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=7647497

Bull Environ Contam Toxicol. 1995 Jun;54(6):833-6.

No abstract available

Preliminary study of synergism of acid rain and diflubenzuron.

Martin PJ, Clark JM, Edman JD.

Department of Entomology, University of Massachusetts, Amherst 01003, USA.

PMID: 7647497 [PubMed - indexed for MEDLINE]


From Toxline at Toxnet

KAOHSIUNG JOURNAL OF MEDICAL SCIENCES; 10 (SUPPL.). 1994. S102-S108.

DENGUE VECTOR CONTROL PRESENT STATUS AND FUTURE PROSPECTS

YAP HH, CHONG NL, FOO A ES, LEE CY

Abstract: BIOL ABS. RRM JOURNAL ARTICLE AEDES-AEGYPTI AEDES-ALBOPICTUS BACILLUS-THURINGIENSIS BACTERIAL LARVICIDE INSECTICIDES CHEMICAL CONTROL

CAS Registry Numbers:
95737-68-1 - Pyriproxyfen
64628-44-0 - Triflumuron
52645-53-1 - Permethrin
40596-69-8 - Methoprene
35367-38-5 - Diflubenzuron
3383-96-8 - Temefos
134-62-3 - Diethyltoluamide (Deet)
121-75-5 - Malathion
• = fluorinated


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8440876

J Appl Toxicol. 1993 Jan-Feb;13(1):67-8.

Comparative study on the effects of five benzoylphenylurea insecticides on haematological parameters in rats.

Tasheva M, Hristeva V.

National Centre of Hygiene and Medical Ecology, Sofia, Bulgaria.

Five benzoylphenylurea insecticides were administered to male Wistar rats for 28 days at oral doses of 100 mg kg-1 each. Elevation of methaemoglobin was found only in the diflubenzuron- and triflumuron treated groups. The number of reticulocytes was increased in all of the treated groups.

PMID: 8440876 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8419158&dopt=Abstract

Environ Mol Mutagen. 1993;21(1):81-6.

In vitro cytotoxic and cell transforming activities exerted by the pesticides cyanazine, dithianon, diflubenzuron, procymidone, and vinclozolin on BALB/c 3T3 cells.

Perocco P, Colacci A, Grilli S.

Istituto di Cancerologia, Universita di Bologna, Italy.

Cytotoxic and cell transforming activities of the pesticides cyanazine, diflubenzuron, dithianon, procymidone, and vinclozolin were investigated in vitro by utilizing the BALB/c 3T3 cell transformation test performed in the presence or in the absence of S-9 mix as an exogenous bioactivation system for the chemicals. All the assayed pesticides were cytotoxic in the absence of S-9 mix, whereas only dithianon exerted cytotoxic effects in the presence of metabolic activation. All the chemicals tested did induce BALB/c 3T3 cell transformation, to a various extent, in the absence of S-9 mix. Cell transforming ability of cyanazine and diflubenzuron was not detectable in the presence of S-9.

PMID: 8419158 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8157470

Invest New Drugs. 1993 Nov;11(4):279-89.

Effects of diflubenzuron and clanfenur on mouse bone marrow cells.

Jenkins VK, Juneja HS, Ives K, Lee S, Perry RR.

Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston.

Diflubenzuron (DFB) and Clanfenur (CFN) belong to a group of compounds called Benzoylphenyl Ureas (BPUs). Several BPUs regulate cell growth in insects and/or inhibit growth of B-16 murine melanomas. In view of potential clinical use for these compounds, DFB and CFN were selected as examples of BPUs and tested for effects on hematopoiesis in C57Bl/6 mice housed in a conventional environment. DFB and CFN exhibit anti-tumor activity in mice, cause little or no morbidity and mortality and rather than causing bone marrow suppression, which is usual for anti-cancer drugs, these agents stimulate hematopoiesis in vivo and in vitro. Stimulation in vivo was evidenced by increased (up to 112%) peripheral blood granulocytes 6 days after a single injection and enhanced granulopoiesis (approximately 25%) in bone marrow up to 18 days after treatment. That effects of DFB and CFN were on hematopoietic stem cells were indicated by 47% and 48%, respectively, increases in numbers of CFUs and 97% and 95%, respectively, increases in CFUgm. Further, bone marrow cells treated in vitro contained about twice the number of CFUs and CFUgm as control bone marrow cells. Almost all of the increase in number of spleen colonies, whether derived from donors treated in vivo or bone marrow cells treated in vitro, was accounted for by a corresponding increase in number of undifferentiated colonies. These data indicate that DFB and CFN treatment enhance numbers of pluripotential stem cells both in vivo and in vitro. The mechanism of enhancement, direct or indirect, remains to be determined.

PMID: 8157470 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8257816

Bull Environ Contam Toxicol. 1993 Dec;51(6):881-8.

No abstract available

Degradational behavior of the pesticides glyphosate and diflubenzuron in water.

Anton FA, Cuadra LM, Gutierrez P, Laborda E, Laborda P.

Environmental Sciences Center, Spanish Council for Scientific Research, Madrid.

PMID: 8257816 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1865887&dopt=Abstract

Nahrung. 1991;35(1):27-31.

Accumulation of diflubenzuron in bolti fish Orechromis niloticus.

Ahmed MT, Eid AH.

Plant Protection Department, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt.

Orechromis niloticus fingerlings were exposed to the insect growth inhibitor diflubenzuron 1-(2,6-Difluorobenzoyl)3-(4-chlorophenyl)urea for 21 days. Diflubenzuron was introduced to the aquariums where fish were maintained at the beginning of the experiment, then its level in water, gills and liver was detected after 1, 7, 14 and 21 days. The fish accumulated diflubenzuron 76 and 99 times greater than the water content when kept in an ambient concentration of 2.5 and 5 mg/l, respectively, indicating a low bioaccumulation potential. Some degradation products of diflubenzuron were found mainly in liver and water.

PMID: 1865887 [PubMed - indexed for MEDLINE]


PAN International Website Book reviews

Diflubenzuron. Environmental Health Criteria, No. 184, WHO, 1211 Geneva 27, Switzerland, 1996, 164pp.

Diflubenzuron The World Health Organisation (WHO) has evaluated the risks to human health and the environment posed by exposure to the insecticide diflubenzuron. The report found diflubenzuron has a low toxicity and is unlikely to present an acute hazard in normal use. A review of studies of long-term dietary administration supports the conclusion that diflubenzuron is not carcinogenic or mutagenic. However, WHO concludes that the main metabolite, 4-chloroaniline (PCA), is carcinogenic in both mice and rats. In humans, and in several animal species, PCA can cause the formation of methaemoglobin (produced from haemoglobin—resulting in the compound no-longer functioning reversibly as an oxygen carrier). PCA has been reported to cause methaemoglobinaemia. This condition occurs when methaemoglobin levels build up in the blood causing cyanosis, headache, dizziness, fatigue, vomiting, nausea and coma in exposed workers and inadvertently exposed newly born infants. Despite this no data on the direct effects of diflubenzuron on human health were available for evaluation. According to WHO the toxicology studies in animals nevertheless support the theory that exposure to 0.02 mg/kg body weight will probably not cause adverse effects in humans. Diflubenzuron.


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2463298&dopt=Abstract

J Environ Sci Health B. 1988 Oct;23(5):439-51.

In vitro effect of profenofos, fenvalerate and dimilin on protein and RNA biosynthesis by rabbit liver and muscle tissues.

el-Sebae AH, Salem MH, el-Assar MR, Enan EE.

Faculty of Agriculture, Alexandria University, Egypt.

The present study was carried out to investigate the effect of Curacron (profenofos), Sumicidin (fenvalerate) and Dimilin (difluobenzuron) on the in vitro rate of protein and RNA synthesis by rabbit liver and muscle tissues. The synthesis of protein and RNA were significantly stimulated in the liver and inhibited in the muscle by graded doses of these insecticides. Profenofos showed maximum effect on protein synthesis in both tissues at a dose of 0.2 microgram/mL, while the maximum effect on RNA synthesis occurred at 0.2 microgram/mL, while the maximum effect on RNA synthesis occurred at 0.2 microgram mL in the liver and at 2 micrograms/mL in the muscle. Fenvalerate caused maximum stimulation in both liver protein and RNA synthesis at a dose of 2 micrograms/mL, and maximum inhibition in the muscle at 10 and 0.2 micrograms/mL for protein and RNA synthesis respectively. The maximum effect of Dimilin on both tissues was reached at 5 micrograms/mL for protein synthesis and at 0.2 microgram/mL for RNA synthesis. The effect of Dimilin on RNA synthesis was more pronounced in both tissues than its effect on protein synthesis, but this trend was reversed in the case of profenofos and fenvalerate. Present data also showed antagonism between these insecticides on the rate of protein and RNA synthesis.

PMID: 2463298 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3095414&dopt=Abstract

J Appl Toxicol. 1986 Oct;6(5):343-8.

Effects of diflubenzuron on the mouse liver.

Young MF, Trombetta LD, Carson S.

Diflubenzuron (DFB), a potent inhibitor of insect chitin synthesis, was administered to Swiss Webster mice in a 30-day oral intubation study. Animal groups received either no treatment, vehicle control (Polyethylene glycol 400), or DFB suspensions at doses of 125, 500, and 2,000 mg/kg body weight. Hepatic glutathione S-transferase activity as well as morphological characteristics were studied. DFB was shown to elicit hepatocellular changes at all dose levels. The activities of three glutathione S-transferases (S-aryl, S-aralkyl, and S-epoxide) were all altered after DFB administration. Light microscopy revealed radial arrays of hepatocellular vacuolization between the portal and central vein areas. Electron-microscopic examination, verified by morphometric analysis, revealed degenerative changes as well as an increased volume density of the endoplasmic reticulum.

PMID: 3095414 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2979938&dopt=Abstract

J Egypt Public Health Assoc. 1988;63(3-4):181-98.

No Abstract available

Hepatotoxicity of some antimoulting compounds in white male mice.

Berberian IG, Enan EE, el-Sabaawi EA, el-Sheweni S.

PMID: 2979938 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9763833&dopt=Abstract

Ned Tijdschr Geneeskd. 1998 Jul 4;142(27):1567-9.

  • Comment in: Ned Tijdschr Geneeskd. 1998 Nov 7;142(45):2488.
  • [A severe anaphylactic shock caused by spraying the oak processionary caterpillar (Thaumetopoea processionea) in North Brabant]

[Article in Dutch]

Bosma AH, Jans HW.

St. Joseph Ziekenhuis, afd. Cardiologie, Veldhoven.

The processionary caterpillar, Thaumetopoea processionea, caused much inconvenience in the Netherlands in 1996-1997; from the medical point of view, mostly itching and skin rash. After contact with stinging bristles of the caterpillar and with the pesticide Dimilin SC-48, of which diflubenzurone is the active agent, a 72-year-old man had to be resuscitated because of ventricular fibrillation caused by hypotension related to relative underfilling and low systemic vascular resistance. He made a good recovery. Such life-threatening situations can be prevented by publicly announcing plague control measures and closing of the affected areas to the population, with ample margins.

PMID: 9763833 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11874045&dopt=Abstract

Sci Total Environ. 2002 Feb 21;285(1-3):237-45.

The stability and persistence of diflubenzuron in marine sediments studied under laboratory conditions and the dispersion to the sediment under a fish farm following medication.

Selvik A, Hansen PK, Ervik A, Samuelsen OB.

Institute of Marine Research, Department of Aquaculture, Bergen, Norway.

A high performance liquid chromatographic (HPLC) method was developed to determine the concentration of diflubenzuron, a delousing agent used in fish farming, in marine mud and shell sand. The recovery of diflubenzuron from mud was 100.8+/-1.1% and 105.5+/-4.3% for shell sand. The limit of quantitation was found to be 0.1 microg g(-1). The stability of diflubenzuron was studied under laboratory conditions in marine sediments at different temperatures (4 and 14 degrees C). No degradation of diflubenzuron occurred in the organic rich mud sediment or in the shell sand sediment during the experimental period of 204 days. Increasing the temperature from 4 to 14 degrees C had no effect on the stability. Furthermore, diflubenzuron showed to be persistent in both mud and shell sand sediment since no detectable diffusion from the sediment to the water phase occurred during the experimental period of 204 days. Increasing the water current in the tanks had no effect on the persistence. Under field conditions, the concentrations of diflubenzuron found in the organic material from sediment traps placed 2 m from the bottom under the cage in a fish farm during medication were high and ranged from 71 to 259 microg g(-1). The concentrations of diflubenzuron in the sediment under the fish farm were, however, low, with a maximum concentration of 5.4 microg g(-1). The dispersion of diflubenzuron to the sediment was limited to less than 20 m from the edge of the cage in every direction. Fifteen months following the medication, only traces (< 0.1 microg g(-1)) of diflubenzuron were detected in the sediment under the fish farm. Possible explanations for this decrease are resuspension and redistribution of sediment and/or oxic degradation of the drug.

PMID: 11874045 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11783663&dopt=Abstract

Environ Sci Technol. 2001 Sep 15;35(18):3804-8.

Persistence of the insecticide Dimilin 45 ODC on conifer forest foliage in an Atlantic-climate ecosystem.

Rodriguez E, Barrio RJ, Goicolea A, Peche R, Gomez de Balugera Z, Sampedro C.

Department of Chemical and Environmental Engineering, School of Technical Engineering, University of the Basque Country, Vitoria-Gasteiz, Spain. iaproure@vc.ehu.es

The oil formulation of diflubenzuron (Dimilin 45 ODC) persisted for 10-12 weeks on the foliage of a conifer forest in an Atlantic-climate ecosystem. Within 22-30 days following treatment, 55-80% of the insecticide had been removed from the foliage. During this period, the concentration of diflubenzuron was higher than 370 ng g(-1). Aerial application at 56.3 g of Al ha(-1) resulted in deposition levels of the insecticide ranging from 867.5 to 1824.4 ng g(-1), depending upon forest characteristics. The results showed that aerial application is only a suitable technique for the treatment of forest areas with dense foliage and/or high tree density and no more than 15% of tree-free area. The only metabolite detected was 2,6-difluorobenzamide, and this persisted on foliage until the first rainfalls occurred. An empirical mathematical correlation was found to express the influence of meteorological variables--rainfall, solar radiation and temperature--on the persistence of the insecticide. These results suggested that degradation of diflubenzuron on foliage could be due to photodegradation. Some recommendations were made to optimize the deposition of the insecticide on foliage and to minimize its persistence and the off-site spray drift.

PMID: 11783663 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11681690&dopt=Abstract

J Econ Entomol. 2001 Oct;94(5):1243-8.

Inheritance of diflubenzuron resistance and monooxygenase activities in a laboratory-selected strain of Lucilia cuprina (Diptera: Calliphoridae).

Kotze AC, Sales N.

New South Wales Agriculture, Elizabeth Macarthur Agricultural Institute, Camden, Australia.

Inheritance of the high-level diflubenzuron resistance shown by a laboratory-selected strain of Lucilia cuprina (Wiedemann) was examined in matings with a susceptible reference strain. Progeny of reciprocal crosses between resistant females and susceptible males showed higher LC50 values than the alternate reciprocal cross, indicating some maternal influence on inheritance of resistance. Resistance was inherited in a codominant (S male x R female) or incompletely recessive (R male x S female) manner. Monooxygenase activities (aldrin epoxidation) of the F1 generations were also intermediate between the levels shown by the parental lines, however, inheritance of enzyme activities showed greater degrees of dominance than for resistance levels. There was also some maternal influence on inheritance of monooxygenase activities. Backcrosses of F1 generations to both susceptible and resistant parents did not fit the expected patterns for a major sex-linked resistance locus, indicating that the maternal influence on resistance inheritance was not associated with sex-linkage of a major resistance gene. The backcross data also failed to fit the model for a single major autosomal gene, suggesting that the resistance in the diflubenzuron-selected strain is polygenic, involving mechanisms additional to monooxygenases.

PMID: 11681690 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11432004&dopt=Abstract

Aust Vet J. 2001 May;79(5):358-62.

Surveys to assess the amount of pesticide in wool and the use of pesticides by woolgrowers in Queensland.

Ward MP, Armstrong RT.

Queensland Department of Primary Industries, Animal Research Institute, Locked Mail Bag 4, Moorooka, Queensland 4105.

OBJECTIVE: To measure the amounts of pesticide residue in wool grown in Queensland between 1997 and 1999, and to describe the use of pesticides for the control of lice infestations and blowfly strike in Queensland sheep flocks. DESIGN: Pesticide residues were measured in a random sample of wool from Queensland clips offered for sale during 1998 and 1999. Information on pesticide use was obtained from a trace-back postal survey.
PROCEDURE: Samples taken from wool lots were tested for the presence and amount of organophosphorus (OP), synthetic pyrethroid (SP) and insect growth regulator pesticides. A questionnaire seeking information on flock characteristics and pesticide use was sent to the manager of each flock from which a wool sample was tested.
RESULTS: The mean amount of OP and SP residue was 2.0 and 0.8 mg/kg, respectively. Ninety-five and 98% of wool samples contained < 9 mg/kg and 7 mg/kg of OP and SP residues, respectively. The mean amount of cyromazine, diflubenzuron and triflumuron was 12.7, 5.8 and 13.0 mg/kg, respectively. The amounts of OP, cyromazine and triflumuron residues were greater in wool from flocks located in southern Queensland.
CONCLUSION: Most (95%; 95% CI, 92-97%) Queensland wool clips grown between 1997 and 1999 meet the suggested Australian maximum acceptable residue amounts for OP and SP pesticides.

PMID: 11432004 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11417653&dopt=Abstract

J AOAC Int. 2001 May-Jun;84(3):901-9.

Determination of five pesticide residues in oranges by matrix solid-phase dispersion and liquid chromatography to estimate daily intake of consumers.

Valenzuela AI, Pico Y, Font G.

Universitat de Valencia, Laboratori, de Toxicologia, Facultat de Farmacia, Burjassot, Spain.

Residues of benzoylphenylurea insecticides (diflubenzuron, hexaflumuron, and flufenuxuron), carboxamide acaricides (hexythiazox), and carbamate insecticides (benfuracarb) were determined in 150 orange fruit samples from September 1998 to June 1999, to estimate exposure of the Valencian population to oranges contaminated with these newly developed pesticides. The method for monitoring these residues is based on matrix solid-phase dispersion and liquid chromatography with UV or atmospheric pressure chemical ionization/mass spectrometry (APCI/MS) detection. Orange samples representing 11 varieties were collected from an agricultural cooperative and examined for the 5 pesticides. In 74.6% of all analyzed samples, the pesticide residues were below detection limits, which ranged from 0.002 to 0.05 mg/kg. Residues were detected in 25.4% of the samples, with higher incidences of diflubenzuron, flufenuxuron, hexythiazox, and benfuracarb; hexaflumuron residues were detected only occasionally. Two different pesticides exceeded maximum residue limits (MRLs) in 4 (2.7%) of the orange samples. Diflubenzuron surpassed 1 mg/kg MRL in 3 samples and flufenuxuron exceeded the 0.3 mg/kg MRL in 3 samples. The estimated daily intake of the 5 pesticide residues during the period was 0.077 microg/kg body weight per day. This value is much lower than the total admissible daily intake proposed by the Food and Agricultural Organization and the World Health Organization.

PMID: 11417653 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10799337&dopt=Abstract

Toxicol Appl Pharmacol. 2000 May 1;164(3):273-9.

Diflubenzuron, a benzoyl-urea insecticide, is a potent inhibitor of TCDD-induced CYP1A1 expression in HepG2 cells.

Ledirac N, Delescluse C, Lesca P, Piechocki MP, Hines RN, de Sousa G, Pralavorio M, Rahmani R.

Laboratoire de Pharmaco-Toxicologie Cellulaire et Moleculaire, INRA, Antibes, 06606, France.

Diflubenzuron (DFB) belongs to a group of compounds called benzoyphenyl ureas acting as chitin synthesis inhibitors, which also inhibit growth of B16 murine melanomas. The present study was designed to investigate the effect of this insecticide, on CYP1A1 expression and induction in human hepatoma cells HepG2. Treatment of HepG2 cells over 72 h with noncytotoxic concentrations of DFB resulted in a strong dose-dependent decrease in constitutive ethoxyresorufin-O-deethylase activity. Moreover, DFB significantly decreased CYP1A1 induction by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) after 24 h exposure, as demonstrated by ethoxyresorufin-O-deethylase (EROD) activity and Northern blot analysis. Additional studies were performed both on parental HepG2 cells and HepG2-241c.1, which were stably transfected with the chloramphenicol acetyltransferase (CAT) reporter gene, cloned under the control of the human CYP1A1 promoter (-1140 to +59). Ribonuclease protection assays (RPA) analysis clearly demonstrated an inhibition of CYP1A1 transcription in both cell lines. Surprisingly, in corresponding experiments using 3-methylcholanthrene (3-MC) as a CYP1A1 inducer, DFB was less effective. Finally, in competitive binding studies using a 9S-enriched fraction of HepG2 cytosol, DFB was capable of displacing [(3)H]-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) from its Ah receptor binding site. Taken together, these results support the involvement of a transcriptional mechanism in the inhibition of CYP1A1 expression in HepG2 cells by DFB, possibly via an Ah receptor antagonism. Copyright 2000 Academic Press.

PMID: 10799337 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9830572&dopt=Abstract

Aust Vet J. 1998 Oct;76(10):698-9.

Residues of insect growth regulators on Queensland wool.

Ward MP, Armstrong RT.

Queensland Department of Primary Industries, Animal Research Institute, Moorooka, Queensland.

PMID: 9830572 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9595184&dopt=Abstract

Bull Environ Contam Toxicol. 1998 May;60(5):702-8.

Implications for the use of diflubenzuron to reduce arthropod populations inhabiting evaporation ponds of the San Joaquin Valley, California.

McCasland CS, Cooper RJ, Barnum DA.

Department of Biology, University of Memphis, TN 38152, USA.

PMID: 9595184 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12232876&dopt=Abstract

Arch Insect Biochem Physiol. 2002 Oct;51(2):91-101.

Significance of penetration, excretion, and transovarial uptake to toxicity of three insect growth regulators in predatory lacewing adults.

Medina P, Smagghe G, Budia F, Del Estal P, Tirry L, Vinuela E.

Proteccion de Cultivos, Escuela Tecnica Superior de Ingenieros Agronomos, Madrid, Spain.

Topical treatment of the predatory lacewing adults, Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) before and after the onset of oviposition with diflubenzuron (DFB) at doses based on the maximum field recommended concentration resulted in a total inhibition of egg hatch due to death of the embryo. In contrast, pyriproxyfen (PYR) and tebufenozide (TEB) did not affect fecundity and egg fertility. To explain these differences in toxicity, the patterns of penetration through the cuticle, distribution inside the insect body, and excretion were studied using [(14)C]-labeled isotopes of each insect growth regulator (IGR). Penetration of DFB and TEB reached about 16 and 26% in 7 days, whereas 88% of PYR had penetrated in 24 h. However, the rate of excretion for PYR was very high, compared to that of DFB and TEB. Low amounts of absorbed radioactivity were recovered from the female body with the exception of DFB, the ovaries and the eggs deposited during a week. DFB and PYR concentration reached a peak in the eggs deposited at the fourth and second day after treatment, respectively. The current data indicate the importance of penetration through the insect cuticle. However, other mechanisms are likely to be involved in the selectivity of the current IGRs towards this beneficial insect. Copyright 2002 Wiley-Liss, Inc.

PMID: 12232876 [PubMed - indexed for MEDLINE]


From Dart Special at Toxnet

Environmental Toxicology and Risk Assessment: Modeling and Risk Assessment (ASTM STP 1317) 1997;6:533-50

Age-specific sensitivity of grass shrimp (Palaemonetes pugio) embryos to sublethal concentrations of diflubenzuron.

Wilson JE

Department of Biology, Morgan State University, Baltimore, MD.

Ovigerous grass shrimp (Palaemonetes pugio) carrying 0.5-, 1-, 3-, 6-, and 8-day-old embryos (i.e., stages 1, 2, 3, 4 and 5, respectively) were exposed continuously for 4 days to a single dose of diflubenzuron (DFB) at sublethal concentrations (0.3 to 5.0 ug/L) in a static system. After the 4-day exposure, the shrimp were transferred to DFB-free seawater for the rest of the embryonic development. When the eggs hatched, the following toxicity-endpoints were measured: Hatchability (% hatch), larval viability (% of larvae surviving to the postlarval stage), duration of larval development from hatching to the postlarval stage, and severity of morphological abnormality in the larvae after hatching. There was no correlation between the age of the embryos at exposure and either hatchability or duration of larval development. Also, severity of abnormality did not vary with age of embryos except at an exposure concentration of 2.5 ug/L. However, within each age group of the embryos, the severity of larval abnormality was and duration of larval development was concentration dependent. Larval viability was significantly (P less than 0.05) affected by the age of the embryos at the time of exposure to DFB. For all the test concentrations, exposure of 0.5- and 1-day-old embryos resulted in larval viability that was similar to the control group (viability greater than 80%). However, when 6- and 8-day-old embryos were exposed to DFB concentrations greater than 0.5 ug/L, larval viability was significantly (P less than 0.05) less than the controls. These results indicate that older embryos (at more advanced stages of development) of the grass shrimp are more sensitive to sublethal DFB concentrations.


From Dart Special at Toxnet

Environ Toxicol Chem 1995;14(8):1345-55

Effects of diflubenzuron on the reproductive success of the bluegill sunfish, Lepomis macrochirus.

Tanner DK, Moffett MF

U.S. Environmental Protection Agency, Environmental Research Laboratory, Duluth, MN.

Exposure to diflubenzuron concentrations of 2.5 ug/L reduced growth of young-of- the-year (Y-O-Y) bluegill by 56 and 86% in replicate enclosures and by 88 and 97% at 30 ug/L. An adult bluegill reproduction study was conducted in six littoral enclosures located in a 2-ha pond near Duluth, Minnesota. Decreased growth of Y-O-Y bluegill resulted from the reduction or elimination of preferred invertebrate prey items by diflubenzuron that led to different and/or less Y-O-Y food consumption. Adult bluegill behavior and spawning, embryo hatching, larval survival until swim-up, and Y-O-Y biomass were also studied. Before the first two diflubenzuron applications, spawning occurred in all enclosures; following the first application, spawning occurred in both control enclosures and one 30-ug/L enclosure. Successful embryo hatching and larval swim-up occurred in all enclosures prior to the first application, and in one control and one 30-ug/L enclosure following application. The Y-O-Y growth was the most sensitive end point, and Y-O-Y biomass was among the least sensitive end points for bluegill reproductive success. The Y-O-Y bluegills (and potentially other fish species) that are exposed to diflubenzuron concentrations of greater than or equal to 2.5 ug/L may experience reduced growth, which can result in greater starvation, increased predation, reductions in over-winter survival, and diminished to poor recruitment.


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7647497&dopt=Abstract

Bull Environ Contam Toxicol. 1995 Jun;54(6):833-6.

No Abstract available

Preliminary study of synergism of acid rain and diflubenzuron.

Martin PJ, Clark JM, Edman JD.

Department of Entomology, University of Massachusetts, Amherst 01003, USA.

PMID: 7647497 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8440876&dopt=Abstract

J Appl Toxicol. 1993 Jan-Feb;13(1):67-8.

Comparative study on the effects of five benzoylphenylurea insecticides on haematological parameters in rats.

Tasheva M, Hristeva V.

National Centre of Hygiene and Medical Ecology, Sofia, Bulgaria.

Five benzoylphenylurea insecticides were administered to male Wistar rats for 28 days at oral doses of 100 mg kg-1 each. Elevation of methaemoglobin was found only in the diflubenzuron- and triflumuron treated groups. The number of reticulocytes was increased in all of the treated groups.

PMID: 8440876 [PubMed - indexed for MEDLINE]


From Dart Special at Toxnet

Chemically Induced Birth Defects 1993;2:675-721

Pesticides.

Schardein JL

International Research and Development Corporation, Mattawan, MI.

Medical Subject Headings (MeSH):
Pregnancy
Animal
Human
Female
Pesticides/*TOXICITY
*Abnormalities, Drug-Induced
2,4,5-Trichlorophenoxyacetic Acid/TOXICITY
Insecticides/TOXICITY

Substance (CAS Registry Number): [Too many to list]

Sodium fluoroacetate (62-74-8)

[Note: the following organofluorines were included]
Diflubenzuron (35367-38-5)
Ethalfluralin (55283-68-6)
Flusilazole (85509-19-9)
Gliftor (8065-71-2) - [Synonym: 1-Chloro-3-fluoro-2-propanol mixt. with 1,3-difluoro-2-propanol]
N-Methyl-N- 1-naphthyl fluoroacetamide [Nissol] (5903-13-9)
Sarin [Synonym: (+-)-Isopropyl methylphosphonofluoridate] (107-44-8)
Sodium fluoroacetate (62-74-8)
Sodium hexafluorosilicate [also known as Sodium fluorosilicate] (16893-85-9)
Soman [Synonym: 1,2,2-Trimethylpropyl methylphosphonofluoridate] (96-64-0)
Sulfuryl fluoride (2699-79-8)
Trifluralin (1582-09-8)


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1593093&dopt=Abstract

J Environ Sci Health B. 1992 Apr;27(2):113-23.

Bioavailability, biological activity and characterization of bound residues of diflubenzuron in wheat.

Aly MA, Dauterman WC.

Department of Toxicology, North Carolina State University, Raleigh 27695.

Wheat grain was treated with radiolabeled diflubenzuron at 100 ppm and stored for various periods; up to 6 months. The grain was surface washed, Soxhlet-extracted with methanol, and the residues determined. A relative constant amount of bound residues (4%), i.e., non-extractable radioactivity, was found 4 months after application and remained constant. More than 97% of the extractable radioactivity in the grain after 6 months was identified as diflubenzuron. When the bound residues were fed to rats, 47% of the administered dose was eliminated via the urine and the remainder via feces within 96 h. Diflubenzuron was the major component in the urine. Adding bound residues to housefly media resulted in a dose-dependent mortality of housefly pupae. Bound residues were biologically active, preventing the emergence of adult houseflies. Supercritical fluid extraction of the bound residues extracted 92% and 96% of the radioactivity associated with grain and feces, respectively. Only diflubenzuron was present in these extracts. The bioavailability and biological activity of bound residues of diflubenzuron have been demonstrated and the identity of the radioactivity was shown to be parent compound. Based on these findings, bound pesticide residues can no longer be ignored or overlooked in the evaluation of pesticide residues and their possible toxicological implications.

PMID: 1593093 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1616600&dopt=Abstract

Crit Rev Toxicol. 1992;22(1):45-79.

Environmental concentrations and aquatic toxicity data on diflubenzuron (dimilin).

Fischer SA, Hall LW Jr.

University of Maryland System, Maryland Agricultural Experiment Station, Queenstown 21658.

The insecticide diflubenzuron (DFB) is commonly used in various mid-Atlantic states for suppression of gypsy moths in hardwood forests. DFB is potentially toxic to nontarget biota because it can enter aquatic systems through aerial application or runoff after precipitation events. Based on this concern, the objectives of this study were to:
(1) compile, review, and synthesize literature on the fate, persistence, and environmental concentrations of DFB in both freshwater and saltwater environments;
(2) compile, review, and synthesize acute and chronic aquatic toxicity data on DFB effects on freshwater and saltwater organisms;
(3) assess possible risk to aquatic biota associated with the use of this insecticide in one specific area (Maryland); and
(4) recommend future research based on the data gaps identified from this study.
DFB has low solubility in water and exists as a technical grade (TG) and wettable powder (WP) formulation. The toxicity of both formulations is similar at concentrations less than 10 micrograms/l. Organic matter is a major factor influencing the adsorption and degradation of DFB in freshwater, saltwater, and sediment. The half-life of this insecticide in freshwater is approximately 3 days at a pH of 10 and temperature of 36 degrees C. At lower pH conditions of 6 and at the same temperature, DFB is more persistent since half-life values of approximately 9 days have been reported. The half-life of DFB in soil is less than 14 days when the particle size was approximately 2 microns. The half-life is generally greater in cool, dry soil than in hot, wet soil. Aquatic
vegetation acts as a sink for DFB by gradually adsorbing the chemical and releasing it over a period of time. Freshwater organisms demonstrated a wide range of sensitivity to DFB. Sensitivity was dependent on body composition (i.e., exo- vs. endoskeleton), trophic level, and life stage. During acute exposures, aquatic invertebrates were more than 25,000 times as sensitive to DFB than fishes. The most acutely sensitive species tested was the Amphipod, Hyallela azteca (96-h LC50 = 1.84 micrograms/l). A mature Plecopteran, Skwala sp., was the most resistant invertebrate species tested in acute tests (96-h LC50 greater than 100,000 micrograms/l). In chronic tests, DFB concentrations of 1 microgram/l or greater were reported to eliminate populations of various Plecopteran (stoneflies) and Ephemeropteran (mayflies) species after 1 month of exposure. A 30-day LC50 of 0.1 micrograms/l DFB was also reported for the Tricopteran, Clistorinia magnifica.(ABSTRACT TRUNCATED AT 400 WORDS)

Publication Types: Review; Review, Tutorial

PMID: 1616600 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2503072&dopt=Abstract

Bull Environ Contam Toxicol. 1989 Jul;43(1):60-5.

No Abstract available

Hematological studies on white male rats exposed to some antimoulting compounds.

Berberian IG, Enan EE.

Central Agricultural Pesticides Laboratory, University of Alexandria, Egypt.

PMID: 2503072 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2422789&dopt=Abstract

Toxicology. 1986 Jun;39(3):307-15.

Effects of chitin synthesis inhibitors on incorporation of nucleosides into DNA and RNA in a cell line from Manduca sexta (L).

Klitschka GE, Mayer RT, Droleskey RE, Norman JO, Chen AC.

Five putative chitin synthesis inhibitors (CSI) were tested to determine if they inhibited nucleoside incorporation into acid precipitable material in a cell line from Manduca sexta (L.). The results varied. Diflubenzuron (DFB) (100 micron) inhibited cytidine incorporation by 38%; EL-494 (100 micron) inhibited adenosine incorporation by 43%; Bay Sir 8514 (100 micron) inhibited uridine incorporation by 24%. Superdiflubenzuron (100 micron) was the worst inhibitor overall (18-22%) for the benzoylphenyl urea CSI. The triazine CSI, CGA 19255, was the best inhibitor tested with 60% inhibition for cytidine and 49% for adenosine incorporation into DNA and RNA. Examination of cells incubated with diflubenzuron by scanning electron microscopy revealed distinct external morphological changes. Transmission electron microscopy showed that crystalline structures accumulated in the cytoplasm of cells treated with DFB. The crystalline structures were assumed to be diflubenzuron and they persisted even after diflubenzuron was removed from the medium.

PMID: 2422789 [PubMed - indexed for MEDLINE]


Environmental Pollution Series A, Ecological and Biological
Volume 41, Issue 1 , 1986, Pages 63-88

This Document
Abstract
Actions
Cited By
Save as Citation Alert
E-mail Article
Export Citationdoi:10.1016/0143-1471(86)90107-8      
Copyright © 1986 Published by Elsevier Science Ltd.
Dynamics of diflubenzuron (dimilin®) concentrations in water and sediment of a supratidal saltmarsh site following repetitive aerial applications for mosquito control
P. A. Cunningham* and L. E. Myers†
* Center for Environmental Systems. Research Triangle Institute, Research Triangle Park, North Carolina 27709, USA
† Center for Medical, Environmental, and Energy Statistics. Research Triangle Institute, Research Triangle Park, North Carolina 27709, USA
Available online 24 June 2003.

Abstract
A field study was conducted to monitor changes in diflubenzuron (DFB) and a degradation product, 4-chlorophenylurea (CPU) in water and sediment collected from a supratidal mosquito breeding lagoon. Three applications of a 0·4% sand granule followed by three applications of a 25% wettable powder formulation were made to the site. Substantial differences in the dynamics of both DFB and CPU concentrations in water were noted among applications. Non-linearity of the logarithm of DFB concentrations in water as a function of time was also evident in some applications. In such cases, the half-life parameter does not characterise the dynamics of the process and is of questionable value.
For four of the six applications, there was strong evidence of a decrease in DFB concentration in water. However, there was not significant evidence of a decrease in DFB concentrations in sediment, which appeared to be a major site for DFB adsorption. Water concentrations for each analyte (DFB, CPU) were negatively correlated with sediment concentrations for the same analyte, suggesting that an exchange of both analytes occurs across the water/sedimetn interface. Also, positive correlations were noted between DFB and CPU in both water and sediment. These correlation findings are counter-intuitive, if it is assumed that changes in DFB and CPU concentrations are mainly due to degradation of the former to the latter.
While DFB concentrations in the supratidal lagoon water tended to remain above 0·4 g litre-1 for 7 days post application, it seems unlikely that this toxic concentration would affect planktonic larval crustaceans in adjacent estuaries if DFB entered these waters via runoff or by flooding of supratidal areas. The persistent DFB concentrations in the water and sediment (~100 gkg-1), however, could be detrimental to detrialfeeding populations of marsh crustaceans (e.g. Uca).

 


From Dart Special at Toxnet

POULT SCI 61:268-271,1982

THE INFLUENCE OF DIFLUBENZURON ON SEVERAL REPRODUCTIVE CHARACTERISTICS IN MALE AND FEMALE LAYER-BREED CHICKENS

KUBENA LF

Taxonomic Name: GALLUS DOMESTICUS
Test Object: AVES, CHICKEN

Sex Treated: MALE; FEMALE
Experimental Conditions: PRECONCEPTION
PRECONCEPTION+

Assay Method:
REPRODUCTIVE TOXICITY
GROWTH
VIABILITY, FERTILITY AND MORTALITY
SKIN AND SKIN APPENDAGES


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6803677&dopt=Abstract

Arch Environ Contam Toxicol. 1982;11(1):1-10.

The effects of diflubenzuron on a complex laboratory stream community.

Hansen SR, Garton RR.

Effects were assessed on the total biological community in complex laboratory streams caused by continuous exposure to diflubenzuron (1-(4-chlorophenyl)-3-(2,6-difluorobenzoyl) urea). The insect fauna suffered direct toxic effects at concentrations of 1.0 microgram/L and greater. The algal and fungal floras were mildly affected at the same concentrations; apparently indirect effects in response to the reduced herbivore and shredder components of the insect fauna. No effects were observed on the bacteria, oligochaetes or gastropods, at any of the test concentrations. Within the insect fauna, differences in sensitivities were observed: mayflies and stoneflies were affected at 1.0 microgram/L, dipterans were affected at 10.0 microgram/L, and coleopterans were apparently unaffected at any of the test concentrations. Effects on caddisflies could not be determined due to their failure to become established in the stream systems. These differences between insect orders in sensitivity, coupled with differences in generation time, may reduce the overall benefits of the insecticide. For example, if diflubenzuron is used for chironomid control, the result may be more severe and longer lasting effects on nontarget mayfly and stonefly populations.

PMID: 6803677 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7175038&dopt=Abstract

J Agric Food Chem. 1982 Nov-Dec;30(6):1227-33.

No Abstract available

In vivo and liver microsomal metabolism of diflubenzuron by two breeds of chickens.

Opdycke JC, Miller RW, Menzer RE.

PMID: 7175038 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6791153&dopt=Abstract

Poult Sci. 1981 Jun;60(6):1175-82.

The influence of diflubenzuron on several weight characteristics in growing male broiler and layer chickens.

Kubena LF.

Diflubenzuron (Dimilin, TH-6040; N-[[(4-chlorophenyl)-amino] carbonyl]-2,6-difluorobenzamide) was fed to male broiler and layer chickens at levels of 0, 2.5, 25, and 250 ppm from 1 day to 98 days of age. Characteristics measured were body weights, grams of feed per gram of body weight, testes weights, liver weights, comb weights, and feet weights. There were no consistent significant differences among the control, 2.5, 25, or 250 ppm groups in any of the characteristics measured. There was a trend for higher body weights in the chickens fed diets containing diflubenzuron.

PMID: 6791153 [PubMed - indexed for MEDLINE]


From Dart Special at Toxnet

BULL ENVIRON CONTAM TOXICOL 25:252-256,1980

ABSENCE OF TRANSFORMATION BY DIFLUBENZURON IN A HOST-MEDIATED TRANSPLACENTAL CARCINOGEN ASSAY

QUARLES JM, NORMAN JO, KUBENA LF


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=387118&dopt=Abstract

Bull Environ Contam Toxicol. 1979 Nov;23(4-5):482-6.

No Abstract available

Effects of feeding diflubenzuron to young male holstein cattle.

Miller RW, Cecil HC, Carey AM, Corley C, Kiddy CA.

PMID: 387118 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=359072&dopt=Abstract

Bull Environ Contam Toxicol. 1978 Aug;20(2):167-9.

No Abstract available

Toxicity of Altosid and Dimilin to juvenile rainbow trout and coho salmon.

McKague AB, Pridmore RB.

PMID: 359072 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=359071&dopt=Abstract

Bull Environ Contam Toxicol. 1978 Jul;20(1):66-70.

No Abstract available

A preliminary study of the effects of diflubenzuron and methoprene on rainbow trout (Salmo gairdneri Richardson).

Madder DJ, Lockhart WL.

PMID: 359071 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=384922&dopt=Abstract

Arch Environ Contam Toxicol. 1978;7(4):483-91.

No Abstract available

Impact of the insect growth regulator diflubenzuron on invertebrates in a residential-recreational lake.

Ali A, Mulla MS.

PMID: 384922 [PubMed - indexed for MEDLINE]


From Dart Special at Toxnet

MAR POLLUT FUNCT RESPONSES(PROC SYMP POLLUT PHYSIOL MAR ORG 1977) 259-270,1979

PESTICIDES: THEIR IMPACT ON THE ESTUARINE ENVIRONMENT

NIMMO DR

PESTICIDES
ALTOSID ( 40596-69-8 )
PERMETHRIN ( 52645-53-1 )
DIMILIN ( 35367-38-5 )


Return to Diflubenzuron Index Page

 
Fluoride Action Network | Pesticide Project | 315-379-9200 | pesticides@fluoridealert.org