Abstract : Over the recent decades, there has been increasing global concern about exposure to work place chemicals and their impact on human health. This study is therefore aimed at assessing the impact of occupational exposure to municipal solid wastes, saw-dusts and paint, on the reproductive hormones levels among exposed workers in Port Harcourt, Nigeria. A cross-sectional analytical study was carried out on 157 apparently healthy male subjects comprising 45 unexposed (control), and 112 exposed (test) subjects. The test subjects consist of 37 workers involved in municipal solid waste disposal, 40 workers in saw-mill, and 35 in paint factory. Information on their anthropometric parameters and duration of exposure were obtained from subjects. 5ml of blood was collected from each subject by venipuncture, processed and serum used for assay of Luteinizing Hormone (LH), Oestrogen and Testosterone levels. The results showed a decrease in the mean level of luteinizing hormone (mlU/ml) among solid waste workers (p<0.05), saw-mill workers (p<0.05) and paint factory workers (p>0.05) when compared with the control subjects. Also, the serum oestrogen (pg/ml) decreased among solid waste workers (p>0.05), saw-mill workers (p<0.05) and paint workers (p<0.05), compared to control group subjects. Similarly, the serum levels of testosterone (ng/ml) decreased among solid waste workers (p<0.05), saw mill workers (p>0.05) and paint factory workers (p>0.05), when compared with control group subjects. The reductions in all the hormones in the test subjects were duration-of-exposure-dependent. This study shows that occupational exposure to municipal solid wastes, saw-dusts and paint decreases the serum levels of male reproductive hormones. This could negatively impacts on their reproductive functions.

Keyword : Reproductive parameters, hormones, industry, workers, infertility

Abstract : Gas flaring activities in Ogbia communities Niger delta region of Nigeria has been on for about sixty (60) years now. These associated flared gases with its constituents are released into the environment, and absorbed into the body of the resident population. This study was therefore aimed at evaluating the effects of the prolong exposure to the flared gases on the serum level of heavy metals and reproductive hormones among residents of these gas flaring communities. A total of 200 adult subjects were involved in the study. It consist of 100 test subjects (50 males and 50 females) randomly selected from communities ≤ 5km from active gas flaring site; and 100 control subjects (50 males and 50 females) from a community about 200km from any gas flaring site. Demographic and socio-economic data of subjects were obtained. 4ml of blood was obtained from each subject and serum used to determine the concentrations of reproductive hormones and heavy metals. The results show significant (p<0.01) reduction in serum Leuteinising hormone, Follicle Stimulating hormone, Prolactin, Testosterone, Progesterone and Oestradiol; with a significant (p<0.01) increase in the serum concentrations of copper, cadmium, nickel, zinc, mercury, arsenic and vanadium among the test subjects, when compared with subjects in the respective control groups. In conclusion, prolong exposure to gas flaring by residents of Ogbia communities results in an abnormal increase in the serum concentrations of heavy metals, which led to impairments in their reproductive hormones; and consequently could impair their reproductive functions and reproductive capacities.

Keyword : Gas flaring, reproductive Hormones, Niger Delta, infertility