Ecological risk assessment of oil & grease (OG) and heavy metals in the surface water of Naf River, Bangladesh
Imran Hossain, Md. Kawser Ahmed, K. M. Azam Chowdhury, Md Moniruzzaman, Mosa. Tania Alim Shampa
Abstract
(Ni) are found 45.69, 39.41, and 6.43, which exceed the threshold limit. The ecological risk index indicates that around 25 % of the total heavy metals show a very high ecological risk and 75 % exhibit a lower ecological risk. Notably, within the very high ecological risk, Cd is responsible for 53 % of this risk, while Pb contributes the remaining 47 %. Increased OG and heavy metal concentrations in the Naf River are likely due to human activities like waste discharge from municipalities, solar power plants, pesticide use, and fishing trawlers. This research offers insights into the current state of the Naf River and guides policymakers toward more effective initiatives.