Distributions, pollution evaluation and health risk of selected heavy metal in surface water of Taylor creek, Bayelsa State, Nigeria

Abstract

Objective This study investigated seasonality in the distribution, pollution evaluation and health risk of selected heavy metal in surface water of Taylor creek, Bayelsa State, Nigeria. Materials and methods Atomic adsorption spectrometry was used to assess heavy metals in 36 water samples from 12 locations in Taylor creek, and pollution indices and health risk due to exposure through oral and dermal contact was determined following standard protocol. Results The concentration of lead, chromium, copper and zinc values ranged from 0.00 to 0.48\xa0mg/L, 0.02–0.42\xa0mg/L, 0.05– 0.61\xa0mg/L and 0.06–0.83\xa0mg/L, respectively, across the various months. The metals were in the order; lead\u2009<\u2009chromium\u2009<\u2009copper\u2009<\u2009zinc in dry season, and lead\u2009<\u2009copper\u2009<\u2009chromium\u2009<\u2009zinc in wet season, an indication of seasonal changes in their distribution. Pollution indices depicts low to moderate contamination with slight variation occurring in both seasons, an indication of varying human activities in the water ways across the sampling stations. The health risk assessment showed that hazard index and hazard quotient values are\u2009<\u20091, an indication of no appreciable non-carcinogenic risks via oral intake and dermal contact with water from Taylor creek. The result further revealed that ingestion is the predominant pathway of obtaining heavy metals from the water. The carcinogenic risk was lower than the permissible predictable lifetime risk of carcinogens (10 −6 –10 −4 ). Conclusion The findings of this study will be quite useful to the resident of the area and appropriate government agencies in decision making with respect to water contamination by heavy metals.