Effect of Chronic Exposure of Parathion/Paraoxon Pesticides on Testicular Functions in Spraying Workers

Objectives: Manufacturing and spraying workers of organophosphate pesticides (OPs) could suffer from testicular spermogenesis and steroidogesis dysfunctions particularly when their degradation is subnormal. Aim: Exploration of spermatogenic and endocrinologic testicular functions and paraoxonase/arylesterase (PON1/ARY) degrading activities of the organophosphate parathion and its oxon in their middle age sprayers. Patients and methods: Forty five parathion (PAR)/ paraoxon (PARO) sprayers (exposed group), provided the laboratory by their semen and blood samples during their working in PAR/PARO spraying. Of them 20 men had intestinal bilharziasis. Also, 20 healthy volunteers who were never exposed to these OPs (nonexposed reference group) provided similar samples. Semen quality and serum pituitary-testicular axis hormones and PON-1/ARY enzymatic activities were determined in the nonexposed control group as well as before and after 1 and 3 months of PAR/PARO exposure as sprayers. Results: Parathion/paraoxon spraying workers had subnormal sperm concentration, motility%, viability% and morphology % 3 months after exposure. Sperm anomalies were not significantly different in presence of bilharziasis in comparison to non-bilharzial sprayers. In addition, PAR/PARO sprayers showed significantly decreased serum total and free testosterone concentrations with a negative feed-back increase of serum FSH and LH levels 3 months after exposure. Also subnormal serum PON-1 and ARY levels were found after prolonged PAR/PARO exposure due to exhaustion of the system by genetic damage. Conclusion: Chronic PAR/PARO exposure induced subnormal semen quality, pituitary-testicular endocrinal function and circulating PON-1/ARY activities with unfavorable reproductive outcomes. Prevention of this occupational hazard is recommended.