Reproductive Effects of Pesticide Exposure

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Reproductive Effects of Pesticide Exposure
Pesticide Health Effects Medical Education
Database (PHEMED)
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Reproductive Impact

• Menstrual Cycles
• Birth defects
• Time to pregnancy
• Small for Age at Birth
• Miscarriages

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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.
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Birth Defects Study Design Issues

• Indirect exposure measurements without
  biomarkers
• Work records
• Places of residence
• Databases
• Questionnaires
• Only cases that survive birth are counted
  (miscarried fetuses?)

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Congenital Anomalies

• 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 Childrens 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.
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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, OPs although not statistically
  significant

Source Curtis KM, Savitz DA, Weinberg CR,
Arbuckle TE. The effect of pesticide exposure on
time to pregnancy. Epidemiology. 1999
Mar10(2)112-7.
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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
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Spontaneous Abortions

• 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
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Low Sperm Count

• Characteristic of Dibromochloropropane (DBCP)
  nematocide exposure
• Occurs with exposure to kepone