Impacts of arsenic contamination on plants and the role of microalgae in arsenic stress mitigation for sustainable agriculture.

Arsenic (As) is a toxic metalloid that is accumulating in agricultural soils and irrigation water. As is occurring from both natural geochemical processes and various anthropogenic activities. Consequently, arsenic contamination is a serious global concern, negatively affecting plant productivity, food safety, and human health. Plants absorb As from the soil through their roots via various transport mechanisms. The absorbed As is further translocated to the shoots and other tissues, where it involved in several metabolic activities and hinders in various physiological and biochemical processes within the plants. Microalgae-based bioremediation, known as phycoremediation, has emerging strategy for mitigating arsenic contamination in affected agricultural soil and water due to its eco-friendly nature, cost-effectiveness, and sustainable applicability. Several microalgal species possess high tolerance capacity, ease of cultivation, strong metal-binding affinity, large surface area, and potential for reuse. These microalgaes have evolved as natural bioremediators with multiple detoxification mechanisms, including biosorption, bioaccumulation, biotransformation, and biomineralization, which enable it to immobilize, transform, or sequester As from contaminated soil, and water. This review explores the relationship between As exposure, As impact on plants system and the role of microalgae as efficient phycoremediators. Furthermore, it focus on the strategies to mitigate the detrimental effects of As contamination through microalgae-based remediation, elucidating the underlying mechanisms of As-induced toxicity and detoxification.