Fluoride Action Network

Sulfuryl fluoride: Natural Resources Defense Council (NRDC) opposes phase out!

Source: Beyond Pesticides Daily News Blog | July 12th, 2011
Industry type: Pesticides

Following the Environmental Protection Agency’s (EPA) denial of Dow AgroSciences’ request for an administrative hearing to keep sulfuryl fluoride on the market, the Natural Resources Defense Council (NRDC) sent a letter to the agency on June 29, 2011 opposing EPA’s phase-out of the toxic fumigant pesticide, which is marketed as a substitute for the outdated, ozone-depleting methyl bromide. According to its letter, the environmental group believes that the “proposed action will imperil EPA’s ability to complete the long-overdue phase-out of methyl bromide, leading to prolonged and increased depletion of the ozone layer, higher levels of ultraviolet radiation, and higher risks of cancer, cataracts, and immunological disorders.” Under pressure from a 2006 petition submitted by Fluoride Action Network (FAN), Beyond Pesticides, and Environmental Working Group (EWG), EPA announced its plan to cancel all allowable pesticide residue levels (tolerances) for sulfuryl fluoride over three years, effectively banning its use in January 2014. The agency found that when residues on food products are combined with fluoridated drinking water and toothpaste, aggregate exposure levels are too high. Beyond Pesticides has repeatedly pointed to non-toxic practices that have eliminated the need for either hazardous fumigant throughout the process.

Manufactured by Dow AgroSciences, sulfuryl fluoride was first registered by EPA in 2004 and marketed as an alternative to methyl bromide, which was being phased out under the Montreal Protocol on Substances That Deplete the Ozone Layer. The Montreal Protocol is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances believed to be responsible for ozone depletion. Because of the work of many organizations, including Beyond Pesticides and NRDC, EPA listed methyl bromide for phase-out under the Clean Air Act and Montreal Protocol in 1991. The amount of methyl bromide produced and imported in the U.S. was reduced incrementally until it was to be completely phased out by January 1, 2005. However, “critical use exemptions” (CUEs) for methyl bromide are permitted under Section 604(d) of the Clean Air Act and the Montreal Protocol. Under Decision IX/6 of the Protocol “a use of methyl bromide should qualify as ‘critical’ only if the nominating Party determines that: (i) The specific use is critical because the lack of availability of methyl bromide for that use would result in a significant market disruption; and (ii) there are no technically and economically feasible alternatives or substitutes available to the user that are acceptable from the standpoint of environment and public health and are suitable to the crops and circumstances of the nomination.” CUEs have been decreasing generally since 2005.

While NRDC believes that the sulfuryl fluoride phase-out will lead to increased methyl bromide CUEs, EPA has stated that it does not hold this view. In its August 2010 Assessment of the Impacts of a Stay of Food Tolerances for Sulfuryl Fluoride on Selected Post-Harvest Commodities, EPA says, “The U.S. has been under intense international pressure to reduce and eliminate methyl bromide uses. Of the 17 developed countries that requested CUEs [critical use exemptions] for 2005, only four countries are still requesting exemptions… The criteria for a critical use exemption are demanding and not easily met. It is improbable that the parties to the Montreal Protocol will approve any additional production of methyl bromide for 2013. It is also unlikely that there will be enough methyl bromide stockpile, pre-2005 inventories, to cover the needs of the post-harvest industry. Because of these restrictions, methyl bromide will not be considered as an alternative to sulfuryl fluoride in this assessment.”

NRDC says it would support sulfuryl fluoride phase-outs for uses with viable alternatives. Its letter states, “NRDC has no objection to EPA’s proposed revocation of sulfuryl fluoride tolerances where no such “risk blow-back” is at issue, i.e., for categories of food uses where there is no current use, or where safe alternatives are available with an appropriate leadtime.”

Beyond Pesticides and FAN cited safer alternatives to sulfuryl fluoride when it objected to its initial registration and requested a hearing under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) in 2004. However, in its response rejecting the request, EPA stated that it was not required to look for safer alternatives when registering pesticides for use. “Whether or not there are safer fumigants than sulfuryl fluoride is not a relevant issue in determining whether it was proper for EPA to establish the sulfuryl tolerances that are subject of FAN’s objections. Subject only to a narrow exception not applicable to sulfuryl fluoride, section 408 establishes a risk-only standard for the approval of tolerances. To establish a tolerance, EPA must determine that the tolerance poses a reasonable certainty of no harm. 21 U.S.C. ¡± 346a(b)(2)(A). Section 408 does not allow EPA to deny tolerances to pesticides that meet this safety standard if other, even-safer pesticides are available.”

Many existing grain and commodity storage facilities are simply too old and outdated to effectively prevent pest infestation, leading to a reliance on toxic fumigation. A clean storage or processing facility, fully and regularly maintained, will be much more easily managed and kept free of pests. Relying on outdated technology leads only to a cycle of toxic dependence and resource depletion. Modern food processing and storage practices effectively prevent pest infestations through careful management of equipment, and conditions, such as keeping the product at appropriate humidity levels. There are many viable alternatives to sulfuryl fluoride and methyl bromide fumigation, including: temperature manipulation (heating and cooling), atmospheric controls (low oxygen and fumigation with carbon dioxide), biological controls (pheromones, viruses and nematodes), and less toxic chemical controls (diatomaceous earth). Neither fumigant is permitted in organic food production and handling.

NRDC, Beyond Pesticides, FAN and EWG all agree that EPA should also reduce aggregate fluoride exposure by reducing or eliminating fluoride in drinking water. The NRDC letter points out that municipal drinking water is by far the greatest route of fluoride exposure.

Sulfuryl fluoride is a dangerous chemical which has been linked to cancer as well as neurological, developmental, and reproductive damages. Sulfuryl fluoride is acutely moderately toxic by oral exposure (Toxicity Category II) and slightly toxic for acute inhalation (Toxicity Categories III and IV) and dermal vapor toxicity (Toxicity Category IV). Residents and workers are at risk for neurotoxic effects from acute exposure. Subchronic studies on rats have indicated effects on the nervous system, lungs, and brain. Developmental and reproductive effects have also been noted in relevant studies on rats. According to the National Research Council, fluorides might also increase the risk of developing Alzheimer’s disease, and boys exposed to fluoride in drinking water are five times more likely to develop osteosarcoma, a rare form of bone cancer.

In addition to its health effects, the chemical has been shown to be a highly potent greenhouse gas. Research has shown that it can be as much as 4,000 times more efficient at trapping heat than carbon dioxide, the leading atmospheric contributor to climate change. It currently exists in the atmosphere at much smaller concentrations than CO2, which is why its use must be curtailed before it becomes even more of a concern.

EPA first registered the agricultural use of sulfuryl fluoride in 2004 as an insecticide and established tolerances for a wide range of crops including cereal grains, dried fruits, tree nuts, cocoa beans, and coffee beans. In 2009, despite the urging of health and environmental advocates, Dow AgroSciences was granted permission to sell sulfuryl fluoride for use in sterilizing agricultural fields as well as for fumigation of food storage, handling, and processing facilities.