Research Journal of Biotechnology Vol. 11 (7) July (2016) Res. J. Biotech 75 Lipid Peroxidation and Biochemical Abnormalities in Tannery Workers exposed to Hexavalent Chromium Ateeq Muhammad 1* and Ali Fawad 2 1. Department of Biotechnology, University of Sargodha, PAKISTAN 2. Institute of Chemical Sciences, University of Peshawar, PAKISTAN *ateeqbiochem@gmail.com Abstract Chromate salts are extensively used in tanning industries; the oxidation process, high temperature and pH in tanning environment converts the Cr (III) into chromium (VI) which is more carcinogenetic and toxic for genetic material in cell free system. The aim of the present study was to investigate whether exposure to hexavalent chromium induces lipid peroxidation and biochemical abnormalities in tannery workers. Chromium level in erythrocytes was determined by by graphite furnace atomic absorption spectrophotometer. The results showed that blood chromium level, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were significantly higher (p < 0.001) while the level of glutathione (GSH) was significantly lower (p < 0.001) in exposed groups compared with control group. The values of liver function tests of tannery workers were found to be within the normal range in all age groups except for the albumin content and alkaline phosphatase (AP) activity. AP activity was significantly higher in both the exposed groups I and II. Albumin level was lowered in both the exposed groups I and II. The present study revealed that prolonged exposure to hexavalent chromium is likely to induce lipid peroxidation and biochemical abnormalities in tannery workers. Keywords: Trivalent chromium, Albumin, Biochemical, Occupational exposure, Alkaline phosphatise. Introduction Chromium has been recognized as one of the toxic metal widely used in industries. Occupational exposure to chromium used in tanning processes causes various health hazards in tannery workers. 1, 2 The workers in the tanneries are exposed to trivalent chromium through air inhalation and intake of contaminated food and drinking water. Chromium exposure increases the risk of dermatitis, ulcer, respiratory illness and lungs cancer. 3 Chromium is found in the workplace in two valence states: Cr (VI) and Cr (III). Trivalent chromium cannot easily cross cell membrane while chromium (VI) can easily pass through cell membrane and can undergo reduction. During reduction of chromium (VI), various reactive forms of chromium are generated: namely Cr (V), Cr (IV), Cr (II) and the stable Cr (III) as well as other reactive species including hydroxyl radical or singlet oxygen which are capable of inflicting oxidative damage to cell. 4-6 The epidemiological studies revealed various health hazards including DNA damage, asthma, dermatitis, chronic bronchitis, chromosomal aberration, hemoglobin changes, metabolic syndrome, back pain and cancer in tannery workers. 7-9 Lipid peroxidation (LPO), the oxidative catabolism of polyunsaturated fatty acids, is widely considered as a general mechanism for cellular injury and death. 10 The free radicals produced during peroxide formation from polyunsaturated fatty acid have harmful effects on cell. 11 Antioxidants are frequently used as an efficient biomarker of oxidative stress. Superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione (GSH) are most commonly used markers. Glutathione plays a protective role in membrane lipids from oxidative damage. Malondialdehyde (MDA) is the final product of lipid peroxidation. 12 Cr (VI) can cause oxidative stress in cell which leads to DNA damage. 13 Glutathione (GSH) and cystein also play a key role in oxidative DNA damage. 14 The reduction of trivalent chromium into divalent chromium leads to oxidative stress by intercellular reducing agents. The reaction between Cr (II) and hydrogen peroxide leads to lipid peroxidation. 15 Lipid peroxidation is also caused by massive production of free radicals. 16 As a result, defense mechanisms of the cell are activated which detoxify the effects of lipid peroxidation. 17, 18 Superoxide dismutase (SOD) helps in conversion of two superoxide molecules to generate oxygen and hydrogen peroxide while GSH is capable to decompose peroxides safely. GSH containing sulfhydryl group is the most abundant non proteinous tri peptide in all cells and it has a protective role against oxidative injury. Peshawar is well known for the leather industry in Khyber Pukhtunkhwa, Pakistan. The effluents from tanneries are released indiscriminately into the open land, natural water bodies and agricultural land resulting in contamination of ground and surface water. Thus the surrounding population living in urban and suburban Peshawar is at high risk of deleterious health effects of chromium. 19