Chronic mustard toxicity on the testis: a historical cohort study two decades after exposure.

We aimed to assess the long-term toxic effects of sulphur mustard (SM) on the testis and male fertility two decades after exposure. A historical cohort study was conducted in 2005. Sixty-four SM-exposed and 64 matched SM-unexposed casualties of the Iraq-Iran conflict were enrolled. Fecundity status, semen indices, hormonal assay results and testis histopathology were evaluated. Male factor infertility was diagnosed in 23 and 5% of married exposed and unexposed casualties, respectively (p < 0.01). All semen indices declined over the 15 years since 1990 among the exposed group. Furthermore, all indices with the exception of sperm motility were significantly lower in the exposed than in unexposed men. The follicle-stimulating hormone level was higher in the infertile than in fertile exposed men (p < 0.001). Testis histopathology of the azoospermic men showed complete absence of spermatogenesis with only Sertoli cells in the seminiferous tubules. SM can be gonadotoxic and its chronic toxicity may be permanent. Germ cells are probably the most susceptible gonadal cells to SM.