Lowered blood copper and cobalt contents in goats reared around lead–zinc smelter

Primary pollution from lead–zinc smelters has been implicated in the contamination of forages and signs of lead toxicosis and elevated blood lead levels have been reported in cattle from areas around such industrial units. Lead has deleterious health effects on the gastrointestinal, renal, nervous and hemopoeitic systems. In the present study, 15 blood samples were collected from goats of various age groups reared around a lead–zinc smelter to assess the lead burden and status of the micronutrients copper, cobalt, zinc and iron in the blood. Six blood samples were also collected from goats reared in areas where chances of lead contamination of soil, water and fodder do not exist, to serve as controls. The mean blood lead level in goats around the smelter (0.316±0.040 g/ml) was many fold higher than the control animals (0.015±0.015 g/ml) and the goats of all the age groups that is from 1 to 1.5 years (0.373±0.093 g/ml), 1.5–2 years (0.380±0.144 g/ml) and above 2 years (0.333±0.062 g/ml) had significantly higher blood lead levels than animals from the unpolluted area. There was significant (P < 0.05) reduction in blood copper and cobalt levels in animals from the contaminated area without any significant effect on blood zinc and iron concentrations. Pooling all the values of the 21 goats to study the effect of lead concentration on blood copper and cobalt revealed negative correlations of −0.530 (P < 0.05) between lead and copper and −0.559 (P < 0.01) between blood lead and cobalt. It is concluded from the study that goats reared around a primary lead–zinc smelter had higher blood lead levels that also affected blood copper and cobalt concentrations in a dose-dependent manner. © 2005 Elsevier B.V. All rights reserved.