Autoimmunity pesticides

Many environmental factors have been implicated in the induction of autoimmunity. One dietary component, iodine, has been well studied as a factor that increases autoimmune thyroid disease.67 68 Based on studies in the OS chicken, the increasing prevalence of autoimmune thyroid disease observed in U.S. and Western European populations has been ascribed to increased use of iodized salt.69 Experimentally, it can be shown that iodinated thyroglobulin is a more potent autoantigen than the equivalent noniodinated molecule. Food additives or pesticides may also be important in contributing to the development of autoimmune disease in susceptible individuals.70... 

Few epidemiologic studies of pesticide use in general, or specific pesticides, in relation to any autoimmune disease. Mechanistic research primarily for hexachlorobenzene and malathion. Mechanisms other than endocrine-disruption should be considered, even for pesticides with endocrine-disrupting properties. 

Holsapple, M.P., Autoimmunity by pesticides a critical review of the state of the science, Toxicol. Lett., 127, 101, 2002. 

Pesticides are widely used worldwide in agriculture, public health, and several indoor conditions. Current evidence related to pesticide autoimmunogenic potential is summarized in Table 8. Hexachlorobenzene is the most intensively studied pesticide in the context of autoimmunity, and it will therefore be addressed separately at the end of this section. 

There is some evidence, either in animal models or following human exposure, that several pesticides used currently or in the recent past can cause slight changes that could be interpreted as autoimmune-like effects . However, data supporting this hypothesis are scarce. In some cases, the mere inclusion of observed changes as indicative of autoimmunity is even questionable, whereas in other cases, results of one study have not been confirmed by a subsequent study. Only few compounds that are no longer in use today (i.e. mercury derivatives, hexachlorobenzene) have been... 

In conclusion, the body of data available shows an equivocal association between pesticide exposure and autoimmunity. However, since doubt still persists, further investigation in the field is needed. 

Sobel ES, Gianini J, Butfiloski EJ, Croker BP, Schiffenbauer J, Roberts SM (2005) Acceleration of autoimmunity by organochlorine pesticides in (NZB NZW)F1 mice. Environ Health Perspect, 113(3) 323-328. 

Exposure to pesticides can provoke a variety of immune reactions. These reactions can be classified into (a) modulation of normal immune responses (immune dysfunction), characteristically manifested as immunosuppression, and (b) pathological enhancement of the immune response, most often manifested as hypersensitivity or autoimmunity. The number of reviews on this subject underscores the interest in and concern for the potential of pesticides to alter immune function (8-15). The two general categories of immune alterations induced by pesticides are discussed below. 

Hypersensitivity. In addition to inducing immune dysfunction, pesticides have the potential to exert immunomodulatory effects through the induction of allergic hypersensitivity and autoimmune disease. Pesticide-related hypersensitivity reactions generally are... 

Pesticide-induced disorders resembling autoimmunity have been reported but are rare. The presence of anti-dieldrin IgC antibody in... 

Much of the available information on immunotoxic evaluation of anticholinesterases involves pesticides. However, exposure to low levels of pesticides does not appear to adversely affect the immune system. The effects observed arc not always dose related and only rarely occur at exposures not producing systemic toxicity. Allergic responses and various degrees of autoimmune diseases have been reported in workers occupationally exposed to pesticides however, this effect may be mediated by alteration of proteins rather than inhibition of cholinesterases. Modulation of immune responses, particularly the interference with host defense mechanisms, has been experimentally induced fora variety of anticholinesterase pesticides. 

Many autoimmune diseases, such as hemolytic anemia, glomerular nephritis, and neutropenia, are induced by certain metals, pesticides, and a number of drugs. In such automimmune disorders, the immune system produces autoantibodies to endogenous antigens, causing damage to normal tissues. 

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