Effect of Environmental and Occupational Exposures to Heavy Metals: The Health Implications

Abstract

The craze for technological development has given rise to environmental safety concerns. Various human activities such as artisanal mining, illegal refining, use of leaded petrol, illegal disposal and burning of toxic waste, absorption of production industries in inhabited areas have led to high contamination and pollution associated with heavy metals. The research was done to explore the effect of low dose exposure to heavy metal mixture using male albino rats as experimental animals. The experimental rats were separated into two equal groups; (i) control receiving only deionized water, (ii) combination of metals (PbCl2+ CdCl2 + HgCl2). Treatment was carried out through oral gavage. Induced low dose heavy metal mixture substantially decreased the follicle stimulating hormone, luteinizing hormone and testosterone levels and significantly increased the prolactin level. It also resulted to hepatotoxicity by significantly increasing the liver enzymes and bilirubin level, thereby reducing the total protein and albumin levels. The lipid profile was also investigated to check the risk associated with the cardiovascular system. The result showed a considerable increase (P<0.05) in triglycerides, total cholesterol, low density lipoprotein and very low density lipoprotein and a significant reduction in high density lipoprotein when compared with the control group. Furthermore, low dose heavy metal mixture induced histopathological changes to the liver. Collectively, our findings clearly highlight that environmental and occupational exposure to heavy metals resulted to hepatotoxicity, risk to the cardiovascular system and changes to the hormonal system.