[Environmental pollutants in maternal milk and cryptorchidism]

Numerous maternal lipophilic compounds are eliminated into milk during lactation, their concentrations reflecting fetal in utero exposure. Some of them are endocrine disruptors. Their role in the occurrence of genital malformation, dysfunction or cancer has been suggested. We wanted to study the exposure of our population and its potential association with cryptorchidism, as few clinical studies are available.

Over three years, we screened for cryptorchidism all boys born alive at or above 34 weeks of gestational age, in two maternity wards (CHU Nice, CHG Grasse). Cryptorchid boys were matched with two controls. Nursing mothers provided a colostrum sample that was screened for 15 compounds known for their antiandrogenic and/or anti estrogenic properties, including dichloro-diphenyl-trichloro-ethylene (DDE), polychlorinated biphenyls (PCBs), dibutylphthalate (DBP) (& metabolite monobutylphthalate-mBP) and hexachlorobenzene (HCB).

Out of 6246 boys, 102 were cryptorchid (1.6%). All available colostrums (56 for cryptorchid and 69 for controls) were contaminated. Median concentrations of DDE, PCBs, HCB and phthalates were higher though not significantly in cryptorchid versus controls. Cryptorchid boys were more likely to be classified in the most contaminated groups for DDE and SigmaPCBs, with a trend for mBP. Odds ratio (OR) for cryptorchidism was increased for the highest score of SigmaPCB, with a trend only for DDE versus the lowest score of those components. Our results are similar to those of a Scandinavian study with comparable design.

Our results show the universal contamination of milk with endocrine disruptors in our area, and support the association between congenital cryptorchidism and fetal exposure to PCBs and possibly DDE, alone or in association with other chemicals.