Carry-over of persistent organochlorine pesticides through placenta to fetus

Objective. As a consequence of environmental exposure, organochlorine pesti cides accumulate in lipid rich-tissues such as maternal adipose tissue and partition to maternal blood serum and umbilical blood serum. To establish t heir distribution in the human body, the concentration gradients of organoc hlorine pesticides between these compartments were determined. Material and methods. Maternal adipose tissue, blood serum and umbilical blood serum sa mples from 64 volunteers admitted for cesarean delivery at Hospital Benito Coquet Lagunes were studied in Veracruz during 1997 and 1998. The pesticide residues were determined by gas chromatography and results obtained from d ifferent sample groups were analyzed using Pearson correlation coefficients and simple lineal regression. Results. Significant results expressed on fa t basis of organochlorine pesticides indicate that 1,1,1-trichloro-2,2-bis( 4-chlorophenyl)ethane (DDT) levels are higher in maternal adipose tissue (4 .51 mg/kg DDE and 1.27 mg/kg pp'DDT), maternal blood serum (4.45 mg/kg DDE and 0.78 mg/kg pp'DDT), and umbilical blood serum (4.70 mg/kg DDE and 0.88 mg/kg pp'DDT), due to greater affinity of DDT for lipids. Conclusions. The statistical evaluation of results and the pairing of samples analyzed indic ate that absorbed organochlorine pesticides cross the placental barrier and reach a balanced state between mother and fetus.