RESUMO
To evaluate the toxicity of formaldehyde on the testicular tissue, it was sprayed at a high concentration for both short and moderate periods of time. Also, the reversibility of such toxic effects was studied after cessation of exposure. Male albino rats were exposed to a concentration of 30 ppm formaldehyde vapour for 6 hours/day, 5 days/week for consecutive 4 and 12 weeks respectively. Furthermore. Some animals were left under similar experimental conditions without any exposure for the same time-intervals after being exposed to the above-mentioned concentration and durations. Plasma concentrations of testosterone, follicle-stimulating hormone and luteinizing hormone were measured. Moreover, histological as well as ultrastructural studies were also done on the testicular tissue using both the light and electron microscopes. Plasma concentrations of hormones showed marked reductions in a time-dependant manner - in formaldehyde exposed animals. This was further rellected on the morphological appearance of the testis which was found to be markedly affected -in also a time-deendent manner- following exposure to formaldehyde. In addition, either the hormonal or morphological changes were - irreversible after cessation of exposure for equal periods particularly after prolonged exposure. It was concluded that heavy exposure to formaldehyde increases the risk for an irreversible testicular affection in a time-dependent manner