Alteration of Endocrine Functions and Reproductive Outcome Following Consumption of Edible Crops Grown Around E-Waste Dumpsite Using Albino Wistar Rat Model

Abstract

Electronic waste (e-waste) is the term used to describe old, end-of-life or discarded appliances using electricity in one form or the other which are destined for reuse, resale, salvage, recycling but most importantly disposal. It contains plethora of metals as well as many other toxic chemicals. Research has confirmed endocrine disruption potentials of e-waste resulting from occupational and environmental exposures. However, not much is known about the effects or the hazard of consuming crops from e-waste dumpsite on health (reproductive health/outcome). Hence, this study aimed at evaluating alterations in pituitary-gonadal hormones levels, histology of the gonads and sperm parameters associated with consumption of food crops harvested around e-waste dumpsite. The area selected for the study was Yenagoa, the Bayelsa State capital which is home to over 350,000 thousand people with hundreds of electronic equipment’s retail stores. Samples; soil, plant (maize, fruited pumpkins, scent leaf), water and sea foods were collected around e-waste dumpsites for laboratory screening and after which the edible plants and some sea foods were obtained and prepared into feed which was used to feed the laboratory experimental animals (albino wistar rats) for a period of three months ad libitum. A standard animal feed was formulated from the powder of the above-mentioned materials and the feed formulated from plants from farm around E-waste dumpsite was used to feed the animals in group B (Test group). Group A serve as control and were fed with commercial pellet. The formulated feeds contained maize as its main source of energy. The samples were screened for the presence of toxic metals such as; lead, mercury, cadmium, nickel, copper, chromium, using a wavelength Perkin Elmer 1100 Atomic Absorption Spectrometer (Oxford Instrument, X-MET8000 series). Twenty-eight rats (fourteen each of male and female) of albino wistar strain, weighing 50-100 g at the beginning of the experimental period were used for this study divided into two groups of fourteen animals each per group (7 male and 7 female) with a wire mesh separating the sexes which was later removed in order to allow animals in the test group to meet for procreation two months to end of the experimental period. Male and female fertility hormones; Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH), Testosterone (TESTO) as well as Progesterone (PROG), Estrogen (EST) and Thyroid Stimulating Hormone (TSH) were determined using Enzyme Linked Immunosorbent Assay (ELISA) methods. Sperm analysis was also done for the male animals alongside histology of the testes. Serum levels of Testosterone, Luteinizing Hormone and Follicle Stimulating Hormone for males, Estrogen for females in the test group (exposed group) were significantly (p<0.05) lower compared with the control group. In contrast, serum TSH were significantly (p<0.05) higher in e-waste exposed population (both male and female) compared with the control group. More so, chromium, Cadmium, Nickel, Lead concentration in our harvested crop used correlated significantly but negatively with testosterone, LH, FSH, TSH and estrogen fluctuations as well as alterations in sperm parametres with 86% of non-motile sperm cells in exposed group. This effect was elucidated also by alteration in the histology of the testes.