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Reproductive Toxicity. Pesticide Health Effects Medical Education Database (PHEMED) 2010. Reproductive. Menstrual Cycles Birth defects Time to pregnancy Small for Age at Birth Miscarriages. Menstrual Cycle Changes. Women using pesticides have 1.5 x increased odds of *
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Reproductive Toxicity Pesticide Health Effects Medical Education Database (PHEMED) 2010
Reproductive • Menstrual Cycles • Birth defects • Time to pregnancy • Small for Age at Birth • Miscarriages
Menstrual Cycle Changes • Women using pesticides have 1.5 x increased odds of * • Longer cycles • Missing a period • Hormonally active pesticides increase odds of missed periods, long cycles, bleeding mid cycle. • Lindane • Atrazine • Mancozeb or Maneb Source: Farr SL, Cooper GS, Cai J, Savitz DA, Sandler DP. Pesticide use and menstrual cycle characteristics among premenopausal women in the Agricultural Health Study. (2004). American Journal of Epidemiology, 160(12):1194-204.
Birth Defects:Study Design Issues • Indirect exposure measurements withoutbiomarkers: • Work records • Places of residence • Databases • Questionnaires • Only cases that survive birth are counted (miscarried fetuses? )
Birth Defects • Consistent findings with • Limb reductions - Uro-genital defects • Central nervous system • Cleft palates/lips: marginal significant w/ maternal exposure • Eye – heart defects • Not definitive until better exposure analysis with the US Children’s Health Study Source: Sanborn M, Cole D, Kerr K, Vakil C, Sanin LH, Bassil K. Pesticides Literature Review. Ontario College of Family Physicians. Toronto 2004.
Time to Pregnancy • Studies suggest that occupational exposure increase time needed to become pregnant • 20% - in women engaged in pesticide activities + husband also engaged in same – but imprecise due to small numbers • Associated with dicamba, glyphosate, 2,4-D, thiocarbamates, OP’s although not statistically significant Source: Curtis KM, Savitz DA, Weinberg CR, Arbuckle TE. The effect of pesticide exposure on time to pregnancy. Epidemiology. 1999 Mar;10(2):112-7.
Effect of Pesticide Exposure on Male Fertility • Decreases in sperm count • Diminished percent of viable sperm • Changes in sperm morphology • Hormonal changes • Higher estradiol and lower LH levels • Lower testosterone • Sperm aneuploidy • Associations to specific pesticides • Fumigants : DBCP (banned soil fumigant) EDB wood fumigant • Insecticides: organosphoshates, pyrethroids (fenverlate ) • Herbicides: 2,4-D, alochlor, metochlor, atrazine Sources: Jurewicz J. IJOMEH 2009 ,Carlsen E. BMJ 1992 and Ratcliffe JM BMJ 1987 and Recio R et al. EHP 2001 and Meeker JD. EHP 2004 and Lifeng T Contraception 2006 and Sean S. EHP 2003
Small for Age at Birth • Probable link • Fetal and maternal blood samples for OP by-products and newborn lengths • Chlorpyrifos and diazinon [by-products measured in fetal and maternal blood] associated to lower birth weight and length* * Whyatt RM et al. Biomarkers in assessing residential insecticide exposures during pregnancy and effects on fetal growth. Tox Applied Pharm 206 (2): 246-254 AUG 7, 2005
Miscarriages • Studies suggest an association • Critical exposure windows and certain pesticides • One - four months before conception • Non use of PPE increased risk 5 fold in one study • Study Method Problems • No data on miscarriage rates in general population • High % go undetected • ?? Role of other farm toxins (animal viruses, heavy metals) largely unknown in studies Sources: Arbuckle et al 1999 and 2001; Garry VF et al 2002