Cognition pesticide exposure

Bosma H, van Boxtel MP, Ponds RW, et al Pesticide exposure and risk of mild cognitive dysfunction (letter). Lancet 356 912-913, 2000 Furst JB, Cooper A Failure of systematic desensitization in 2 cases of obsessive-compulsive neurosis marked by fears of insecticide. Behav Res Ther 8 203-206,1970 Gauthier E, Fortier I, Courchesne F, et al Environmental pesticide exposure as a risk factor for Alzheimer s disease a case-control study. Environ Res 86 37-45, 2001... 

Neurotoxicity is the result of improper (careless) use, handling, and negligence in the management of chemical substances such as metals, food additives, pesticides, industrial solvents, cosmetics, radiation treatment, and drug therapies. Depending upon route and dose of exposure, the symptoms of neurotoxicity appear immediately after exposure or are delayed. The symptoms include limb weakness or numbness loss of memory, vision, and/or intellect headache cognitive and behavioral problems and sexual dysfunction. Children and workers with certain existing health disorders are more vulnerable to the adverse effects of neurotoxic chemicals. 

One of the major concerns aroused by exposures to chemicals that affect the nervous system is their potential to adversely impact cognitive functions such as learning and memory. Such a concern certainly has precedent. Lead exposure at high levels can leave children with permanent mental retardation. Recently, it has been demonstrated that even very low levels of lead exposure (i.e., environmental exposures) can produce subtle changes in cognitive processes. Pesticides are known to exert pronounced effects on cholinergic neurotransmitter systems, the very system that has been repeatedly implicated as a causative factor in Alzheimer s disease. 

In summary, the above studies show that neurobehavioral evaluation of pesticide workers reveal increased prevalence of neurologic symptoms and changes in neurobehavioral performance indicative of mild cognitive and psychomotor dysfunction. These effects appear to be more prevalent during the period of exposure, but also persist beyond the period of exposure. Total cumulative exposure seems to be a greater risk factor for poor performance than any other covariant. Deficits in visuomotor speed as indexed by the digit symbol substimtion test and the trailmaking tests have been shown to be consistently effected as well as tests of selective attention and memory... 

As noted previously, the neurobchavioral effects of chronic pesticide expo.sure in humans include psychomotor and cognitive functions, affect, vibration. sensitivity, and balance. A survey of the animal literature revealed 15 papers on this topic in which exposure lasted at least 30 days ... 

O. A. Timofeeva, C. S. Roegge, F. J. Seidler, T. A. Slotkin and E. D. Levin, Persistent cognitive alterations in rats after early postnatal exposure to low doses of the organophosphate pesticide, diazinon, Neurotox-icol. TeratoL, 2008, 30, 38-45. 

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