Heavy metals in the soil, water, plants, and river sediments of Bangladesh: A synthesis

Heavy metals (HMs) contamination is an emerging environmental and public health issues in south Asian country like Bangladesh. HMs from various anthropogenic sources accumulate in the soil, are taken up by plants and entering our food chain, which causes health disorder. However, this study synthesizes updated data on heavy metals contamination in agricultural soils, water, sediments, and food crops across the major industrial areas of Bangladesh from 2010 to 2024. We found that the agricultural soils surrounding of the Dhaka city is highly contaminated with Mn, Zn, Cu, Pb, Cr, Ni, As, Cd. Heavy metals content in water from Buriganaga and Sytalokka river of Dhaka city was greater in compared to countryside river. Similarly, the plants growing near Dhaka city were highly contaminated with HMs (Zn, Mn, Cu, Pb, Ni, Cr), which were Oryza sativa and Amaranthus dubius. Furthermore, in case of sediments, Sytalokka river sediment followed by Buriganga were contained higher content of heavy metals like Cd, Pb, Ni, Zn, Cr and Cu in compared to the other rivers across the Bangladesh. However, different remediation strategies like application of organic amendments, phytoremediation, bioremediation are currently using across the Bangladesh to limit the plant uptake and food chain contamination. This synthesis will provide baseline information and first nationwide comparison of heavy metals data among the different regions of Bangladesh that can be used by policymakers for risk prioritization over the country. Furthermore, this study underscores the urgent need for policy interventions to mitigate heavy metal pollution and ensure sustainable food safety.