Geochemistry, Distribution and Toxicity of Barium in Terrestrial Ecosystem

Barium (Ba), a naturally occurring alkaline earth metal, has gained attention due to its environmental prevalence and potential toxicity. This review examines the sources of Ba in the environment, its distribution across ecosystems, and its toxicological impacts on plants and human health. Ba is widely distributed through natural processes such as the weathering of Ba-rich minerals like barite and witherite, volcanic eruptions, and biological uptake by certain plants and anthropogenic activities, including industrial discharges, oil and gas drilling, and improper waste disposal. Consequently, Ba accumulates in soils and water ecosystems, with concentrations influenced by geological and industrial factors. While Ba in its natural form generally exhibits low toxicity, it shows a dose-dependent impact on the physiology and growth of plants. Aquatic organisms are particularly vulnerable, as Ba disrupts physiological processes, threatening aquatic ecosystems. Regulatory agencies, including the Environmental Protection Agency (EPA) and the World Health Organization (WHO), have established guidelines for acceptable Ba levels in drinking water and soil to safeguard human health and the environment. This review emphasizes the critical need to understand Ba's sources, distribution patterns, and toxicological impacts to protect living organisms and environmental health.