Environmental Factor, November 2005, National Institute of Environmental Health Sciences
Papers of the Month - AUGUST 2005
By Jerry Phelps
1) Furlong CE, Cole TB, Jarvik GP, Pettan-Brewer C, Geiss GK, Richter RJ, Shih DM, Tward AD, Lusis AJ, Costa LG. Role of paraoxonase (PON1) status in pesticide sensitivity: genetic and temporal determinants. Neurotoxicology. 2005 Aug;26(4):651-9.
Implications: These studies build on the previous results describing the susceptibility of young children to organophosphate insecticides. The most important conclusion is that PON1 enzyme level and individual phenotype are both critical for determining an individual's response to organophosphate exposure. The results indicate that children less than 2 years old, especially those homozygous for PON1Q192, would be predicted to be particularly susceptible to chlorpyrifos oxon toxicity.
2) Rohlman DS, Arcury TA, Quandt SA, Lasarev M, Rothlein J, Travers R, Tamulinas A, Scherer J, Early J, Marin A, Phillips J, McCauley L. Neurobehavioral performance in preschool children from agricultural and non-agricultural communities in Oregon and North Carolina. Neurotoxicology. 2005 Aug;26(4):589-98.
Implications: This study points out the need for additional larger studies aimed at determining whether low-level organophosphate pesticide exposures produces deficits in standardized test performance in children of agricultural workers. It also illustrates the importance of proper pesticide application and improved hygiene in pesticide applicators to prevent exposures in their children.
3) Hafeman DM, Ahsan H, Louis ED, Siddique AB, Slavkovich V, Cheng Z, van Geen A, Graziano JH. Association between arsenic exposure and a measure of subclinical sensory neuropathy in Bangladesh. J Occup Environ Med. 2005 Aug;47(8):778-84.
Implications: These findings add to the body of knowledge that chronic arsenic exposure through contaminated drinking water is associated with sensory peripheral neuropathy. Further research is necessary to elucidate a true dose-response relationship, but this study shows a clear connection between individual arsenic exposure and adverse nervous system effects.
4) Abraham JH, Finn PW, Milton DK, Ryan LM, Perkins DL, Gold DR. Infant home endotoxin is associated with reduced allergen-stimulated lymphocyte proliferation and IL-13 production in childhood. J Allergy Clin Immunol. 2005 Aug;116(2):431-7.
Implication: Household endotoxin exposure was associated with decreased production of the t-helper cell cytokine interleukin 13. The results of this study are consistent with the hypothesis that early life exposure to endotoxin protects against allergic diseases and allergy later in life.