Chlorpyrifos Exposure During Perinatal Period Affects Intestinal Microbiota Associated With Delay of Maturation of Digestive Tract in Rats

J Pediatr Gastroenterol Nutr. 2015 Jul;61(1):30-40. doi: 10.1097/MPG.0000000000000734.


Objectives: Pesticide exposure via residues in food may be especially harmful when it takes place in the developing child. The present study was designed to assess the impact of perinatal exposure to chlorpyrifos (CPF, an insecticide known to cross the placental barrier).

Methods: Female rats were exposed to oral CPF (1 or 5 mg kg day vs vehicle controls) from gestation onset up to weaning of the pups that were individually gavaged (CPF or vehicle) thereafter. Two developmental time points were studied: weaning (day 21) and adulthood (day 60). After sacrifice, samples from the intestinal tract and other organs underwent microbiological and histological analyses.

Results: Rat pups exposed to 5 mg kg day CPF were both significantly smaller (body length) and lighter than controls. Exposure to CPF was associated with changes in the histological structures (shorter and thinner intestinal villosities), an intestinal microbial dysbiosis, and increased bacterial translocation in the spleen and liver. These significant microbial changes in the gut were associated with impaired epithelium protection (mucin-2) and microbial pattern recognition receptor (Toll-like 2 and 4) gene expression.

Conclusions: Exposure to CPF during gestation and development affected the pups' intestinal development, with morphological alteration of the structures involved in nutrient absorption, intestinal microbial dysbiosis, alteration of mucosal barrier (mucin-2), stimulation of the innate immune system, and increased bacterial translocation. Perinatal exposure to CPF may therefore have short- and long-term impacts on the digestive tract.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Bacterial Translocation / drug effects
  • Chlorpyrifos / adverse effects*
  • Cholinesterase Inhibitors / adverse effects*
  • Diet*
  • Female
  • Gastrointestinal Microbiome / drug effects*
  • Gastrointestinal Tract
  • Growth / drug effects
  • Insecticides / adverse effects*
  • Intestines / drug effects*
  • Intestines / growth & development
  • Intestines / microbiology
  • Liver / microbiology
  • Maternal Exposure / adverse effects*
  • Mucin-2 / metabolism
  • Pregnancy
  • Rats, Wistar
  • Spleen / microbiology
  • Toll-Like Receptors / metabolism
  • Weaning


  • Cholinesterase Inhibitors
  • Insecticides
  • MUC2 protein, human
  • Mucin-2
  • Toll-Like Receptors
  • Chlorpyrifos