15/09/2009

Non-cancer health effects of pesticides: systematic review and implications for family doctors

Can Fam Physician. 2007 Oct;53(10):1712-20

Chesley Medical Clinic, Box 459, Chesley, ON. msanborn@sbghc.on.ca
OBJECTIVE: To investigate whether there are associations between exposure to pesticides and 4 chronic non-cancer health effects: dermatologic, neurologic, reproductive, and genotoxic effects. DATA SOURCES: We searched PreMedline, MEDLINE, and LILACS using the key word pesticide combined with the term for the specific health effect being searched. Reviewers scanned the references of all articles for additional relevant studies. STUDY SELECTION: Studies since 1992 were assessed using structured inclusion and quality-of-methods criteria. Studies scoring <4 on a 7-point global methodologic quality scale were excluded. In total, 124 studies were included. These studies had a mean quality score of 4.88 out of 7. SYNTHESIS: Strong evidence of association with pesticide exposure was found for all neurologic outcomes, genotoxicity, and 4 of 6 reproductive effects: birth defects, fetal death, altered growth, and other outcomes. Exposure to pesticides generally doubled the level of genetic damage as measured by chromosome aberrations in lymphocytes. Only a few high-quality studies focused on the dermatologic effects of pesticides. In some of these studies, rates of dermatitis were higher among those who had had high exposure to pesticides on the job. CONCLUSION: Evidence from research on humans consistently points to positive associations between pesticide exposure and 3 of the 4 non-cancer health outcomes studied. Physicians have a dual role in educating individual patients about the risks of exposure and in reducing exposure in the community by advocating for restrictions on use of pesticides.
PMID: 17934035

Effects of pesticide exposure on the human immune system

 Hum Exp Toxicol. 2008 Sep;27(9):671-80
Corsini E, Liesivuori J, Vergieva T, Van Loveren H, Colosio C.
Laboratory of Toxicology, Department of Pharmacological Sciences, University of Milan, Milan, Italy emanuela.corsini@unimi.it.
Epidemiological evidence from Western countries indicates that the prevalence of diseases associated with alterations in the immune response, such as asthma, certain autoimmune diseases and cancer, are increasing to such an extent that it cannot be attributed to improved diagnostics alone. There is some concern that this trend could be, at least, partially attributable to new or modified patterns of exposures to chemicals, including pesticides. The purpose of this article is to review the evidence on pesticide immunotoxicity in humans. Overall, the available data are inadequate to draw firm conclusions on the immunotoxic risk associated with pesticide exposure. The available studies on the effects of pesticides on the human immune system have several limitations, including limited data on exposure levels, heterogeneity of the applied methods, and difficulties in assessing the prognostic significance of observed slight changes and in the interpretation of the reported findings. Further studies are needed and preferably as prospective studies, comparing pre- and post-exposure data in the same group of subjects and including an appropriate non-exposed control group. More knowledge is required regarding the prognostic significance of the small changes observed.
PMID: 19042949