Arsenic pollution and its impact on agricultural production, including the ecosystem services delivered by biodiversity

Abstract

Arsenic (As), a noxious metal(loid) widely available in the biosphere, originates mainly from geogenic and anthropogenic origin. Massive global development and industrialization, using pesticides carrying arsenic, arsenical animal feeds, medicine, mining, aquifer sediments, coal burning, and microbial and natural processes continuously release this obnoxious bane to the natural environment and pollute soil and water. Inorganic (iAs) species, mainly arsenate and arsenite, are comparatively more lethal than methylated species. However, pentavalent [As (V)] organic species are nearly non-toxic. An elevated level of arsenic has been found in various crops and feeds consumed by humans and animals. This notable carcinogen threatens human health by drinking arsenic-polluted freshwater and/or ingesting arsenic-adulterated food like cereals, fruits and vegetables grown in arsenic-polluted soil or grown using arsenic-rich irrigation water. Arsenic pollution exerts an irreversible harmful effect on the aquatic and terrestrial ecosystem as well. Much research has been carried out in the last couple of centuries on arsenic pollution and reported its ability to influence the agro-ecosystem to a great extent, including plant accumulation, phytotoxicity, and land degradation. However, underground water is considered the principal source of arsenic pollution, Iron plaque, sulphur oxides, organic matter, microbiome activities and many other factors responsible for speciation, bioavailability and toxicity of As to the environment. This review attempts to comprehend the global arsenic pollution occurrence, its forms, bioavailability and toxicity to humans and microbiota, translocation and accumulation in plants and impact on crop yield. Besides providing the insights, the ultimate targets of this desktop study are to ascertain probable knowledge gaps linked to crop productivity and ecosystem benefit losses that need further investigation.