Abstract

The number of capillary blood eosinophils and the prevalence of bronchial hyperresponsiveness (BHR) were compared between schoolchildren living in a polluted area (Ardal) and unpolluted area (Laerdal). In Ardal there is an aluminium smelter emitting sulphur dioxide and fluoride to the environment. Daily measurements of these pollutants in ambient air were available. The mean number of eosinophils in Ardal was 220 x 10(6)/l compared with 106 x 10(6)/l in Laerdal. The prevalence of BHR was 15.9% in Ardal and 11.8% in Laerdal. The odds ratio of having BHR in relation to these pollutants during the last 24 hours were: 1.12 (95% confidence interval (CI) 1.01 to 1.24) by increasing sulphur dioxide with 10 micrograms/m3, and 1.31 (95% CI 1.07 to 1.60) when fluoride exposure increased with 1 micrograms/m3. Similarly, these exposures were associated with a decrease in eosinophils of -21 x 10(6)/l (95% CI -36 to -6) and -52 x 10(6)/l (95% CI -98 to -8), respectively, in atopics. It is hypothesised that recent exposure to irritants induces changes in the airways leading to BHR in addition to recruitment of eosinophils to the airways in atopic subjects.

• Related Studies :

  • Allergen sensitization and exposure to irritants in infancy

    We investigated the relationship between residence in the neighbourhood of an aluminium smelter and the prevalence of atopy in schoolchildren (7-13 years of age). Atopy was assessed in 556 of the 620 participants by a skin prick test with eight common aeroallergens. The median exposures to sulphur dioxide and fluoride

  • Inflammatory responses of rat alveolar macrophages following exposure to fluoride

    Inhalation exposure to fluoride compounds has been associated with respiratory failure. We have addressed effects of fluoride on alveolar macrophages and lung responses to intratracheally (i.t.) instilled fluoride in rats. I.t. instillation of fluoride at doses of 200 and 400 microg F/rat caused significant polymorphonuclear leukocyte (PMN) infiltration in the

  • Inflammatory markers in bronchoalveolar lavage fluid from human volunteers 2 hours after hydrogen fluoride exposure

    Fluoride has been in focus as a possible causal agent for respiratory symptoms amongst aluminium potroom workers for several decades. Previously, using bronchoalveolar lavage (BAL), we demonstrated airway inflammation in healthy volunteers 24 hours after exposure to hydrogen fluoride (HF). The objective of the present study was to examine early

  • Fluoride in Drinking Water: A Scientific Review of EPA’s Standards.

    Excerpts: Summary Under the Safe Drinking Water Act, the U.S. Environmental Protection Agency (EPA) is required to establish exposure standards for contaminants in public drinking-water systems that might cause any adverse effects on human health. These standards include the maximum contaminant level goal (MCLG), the maximum contaminant level (MCL), and the secondary

  • Suppression of pulmonary antibacterial defenses mechanisms and lung damage in mice exposed to fluoride aerosol

    In endemic fluorosis areas in China associated with coal burning, indoor airborne fluoride pollution is severe. To determine the effects of fluoride aerosols on pulmonary antibacterial defense mechanisms and lung damage, mice were exposed to various concentrations of fluoride aerosol (2, 5, or 10 mg/m3) or filtered air (control) for

• Related FAN Content :

  • Fluoride Enhances Toxicity of Beryllium

    Occupational exposure to beryllium is well-documented to put workers' health at risk. The two principal targets of beryllium poisoning are the respiratory system and the skin. Of all beryllium compounds, beryllium fluoride complexes (including beryllium fluoride and beryllium oxyfluoride) appear to be the most toxic. As shown below, studies dating back

  • Fluoride & the Immune System - Summation from the US National Research Council (2006)

    “There is no question that fluoride can affect the cells involved in providing immune responses. The question is what proportion, if any, of the population consuming drinking water containing fluoride at 4.0 mg/L on a regular basis will have their immune systems compromised? Not a single epidemiologic study has investigated whether fluoride in the drinking water at 4 mg/L is associated with changes in immune function. Nor has any study examined whether a person with an immunodeficiency disease can tolerate fluoride ingestion from drinking water.”

  • Respiratory Risks from Occupational Fluoride Exposure

    Starting in the 1930s, scientists have observed that workers exposed to airborne fluorides suffer from an elevated rate of respiratory disorders. For over 50 years, however, US government and industry scientists made repeated assurances that the allowable level of fluoride dusts and gases in industrial workplaces would not cause any

  • Does Fluoride Ingestion Affect Developing Immune System Cells?

    Considerations, supported by some published experimental evidence, suggest that fluoride released during the resorption of high-fluoride bone may produce detrimental effects not only on bone cells but on developing cells of the immune system.

  • Is the Ingestion of Fluoride an Immunosuppressive Practice?

    This paper records several observations which suggest that habitual ingestion of small doses of fluoride, even as small as the 1 mg/L contained in fluoridated water, may decrease the function of the immune system.