Assessment of Carcinogenic Risk and Non-Carcinogenic Health Hazard from Exposure to Toxicants in Water from the Southwestern Coastal River System in Ghana

ABSTRACT

This study evaluated cancer risk and non-cancer human health hazard from exposure to the toxicants such as As, Cu, Pb, Zn, Mn, and CN in water from a southwestern river system in Ghana that drains through gold mining areas, using 108 water samples collected with random sampling techniques and analyzed in accordance with standard methods of chemical analysis outlined by the U.S. Environmental Protection Agency (USEPA). The concentrations of Cu and Zn were within World Health Organization and USEPA guideline values; Mn, free cyanide, As, and Pb values in most cases either exceeded USEPA and WHO values or both. The concentrations of the toxicants were used as input parameters in the cancer and non-cancer study that was conducted in line with USEPA risk assessment guidelines. The results of As cancer health risk revealed higher risk cases in two locations (Potroase and Dominase); non-cancer health risk for As was higher in 10 of the 14 locations, with other metals being of health concern at few locations in the study area. In conclusion, the findings of this study hold several policy implications as residents of mining communities still depend on these water bodies as their source of drinking water.

Key Words:

• cancer risk and non-cancer health hazards
• toxicants
• hazard index
• Densu
• Birim
• Pra
• Ankobra
• Tano
• Offin
• and Kakum Rivers
• Ghana

Additional information

Funding

The authors are grateful to the Government of Ghana for providing funds for this study.