Heavy metals in soils along unpaved roads in south west Cameroon: Contamination levels and health risks
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Soils enriched with heavy metals from vehicular emission present a significant exposure route of heavy metals to individuals using unpaved roads. This study assessed the extent of Cd, Cr, Co, Cu, Ni, Pb and Zn contamination of soils along unpaved roads in Cameroon, and the health risks presented by incidental ingestion and dermal contact with the soils using metal contamination factor (CF) pollution load index, hazard quotients (HQ) and chronic hazard index (CHI). CF values obtained (0.9–12.2) indicate moderate to high contamination levels. HQ values for Cr, Cd and Pb exceeded the reference doses. Moderate health hazard exists for road users in the areas with intense anthropogenic activities and high average daily traffic (ADT) volume according to CHI values (1–4) obtained. The economy and quality of life in cities with unpaved roads could be threatened by health challenges resulting from long-term exposure to heavy metal derived from high ADT volumes.
KeywordsIncidental soil ingestion Vehicular emission Hazard quotients Chronic hazard index Contamination factor
The author acknowledges the assistance of Dr. L Motsei of the mineral laboratory in Animal Health Department, and Mr. L Kgosieng, Mr. KP Mogale, and Mr. OD Rapetsana of the Crop Science Department all in North West University (Mafikeng Campus) for assistance with analyses of samples and Mr. J Sakwe and Mr. Ngole EE for assistance with collection of soil samples.
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