Researchers evaluated 117 boys in a village where endosulfan has been aerially sprayed for more than 20 years and 90 comparable boys from a nearby village with no such exposure history. For each group, the researchers performed physical examinations and recorded clinical history, sexual maturity rating, and blood levels of various hormones. The study found a higher prevalence of congenital abnormalities related to testicular descent in the study group, but it was not statistically significant due to a small sample size.
“Our study results suggest that endosulfan exposure may delay sexual maturity and interfere with hormone synthesis in male children,” the study authors write. “The practice of aerial spraying of endosulfan was discontinued in December 2000. Serum endosulfan residue levels were significantly higher in the study population than in the control group even 10 months after the last aerial spray.”
Endosulfan has been banned in several countries, including Cambodia, Colombia, Germany, Sweden, Norway, Indonesia, and others. Its use is severely restricted in at least 20 other countries.
Commenting on the study, Dr. Jim Burkhart, science editor for EHP, says, “This is the first human study to ever measure the effects of endosulfan on the male reproductive system. Decades of spraying this pesticide, and only this pesticide, on the village provided a unique opportunity to analyze its impact. Although the sample size is somewhat limited, the results are quite compelling.”
The lead author on the study was Habibullah Saiyed of the National Institute of Occupational Health (Indian Council of Medical Research). Other authors were Aruna Dewan, Vijay Bhatnagar, Udyavar Shenoy, Rathika Shenoy, Hirehall Rajmohan, Kumud Patel, Rekha Kashyap, Pradip Kulkarni, Bagalur Rajan, and Bhadabhai Lakkad.