Metal extent in blood of livestock from Dandora dumping site, Kenya: Source identification of Pb exposure by stable isotope analysis

摘要

Nairobi city in Kenya produces 2000 tons/day of garbage, and most of it is dumped onto the Dandora dumping site, home to a quarter-million residents. This study was conducted (1) to assess the contamination levels of nine metals and a metalloid (arsenic) in the blood of pigs, goats, sheep and cattle from Dandora, and (2) to identify a possible source of lead (Pb) pollution. Cadmium (Cd, 0.17-435 mu g/kg, dry-wt) and Pb (90-2710 mu g/kg) levels in blood were generally high, suggesting human exposure to Cd through livestock consumption and Pb poisoning among pigs (2600 mu g/kg) and cattle (354 mu g/kg). Results of Pb isotope ratios indicated that the major exposure route might differ among species. Our results also suggested a possibility that the residents in Dandora have been exposed to the metals through livestock consumption. (C) 2015 Elsevier Ltd. All rights reserved.