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The ecosystem (land, water, air) and the organisms that inhabit it are exposed to various heavy metals at varying levels. However, concerns arise when the potential exist for the levels of these toxicants to exceed the regulatory thresholds. Arsenic is a well-known soil and water contaminant with reported toxic and detrimental risks to the ecosystem, human health, aquatic and terrestrial animals, and plants. Intake of arsenic contaminated water and food diet form the major source of arsenic exposure to humans. Rice paddy rice (Oryza sativa), a major staple food for many countries of the world has been reported to have the capacity to accumulate a large amount of arsenic from contaminated soil or from contaminated irrigation water. The sources of these arsenic could be as a result of old agricultural practices that utilized arsenate insecticide. Chinese fern has been identified as a potential agent for the phytoremediation of arsenic contaminated soil. Additionally, biochars and charcoal have been used for the remediation of Pb, Cu, Zn, Cd from contaminated water. The project reported here investigated the use of charred rice hulls for the remediation of arsenic contaminated rice farm in the North-Western part of Louisiana. Results demonstrate that rice is an accumulator of arsenic if the soil is contaminated with arsenic. Irrigation water was not a source of arsenic contamination for this project for all the irrigation water samples showed no trace of arsenic. Furthermore, the rice hull and rice straw from previous year used in the preparation of the charred biomaterial appear to be contaminated and thus, increased the soil arsenic but decreased arsenic uptake into the rice grain

Lead, a heavy metal, is a well known contaminant in water and has been reported to cause serious health implications to humans, animals, and plants. One of the processes for heavy metal remediation of contaminated water is chemical precipitation. In this present work, chemical precipitation of lead from a contaminated aqueous matrix by chlorides, carbonates, and sulfates of sodium and calcium was compared to lead removal by molecular sieves and biomaterials (fishbone, grape and spinach). The order of lead removal from 1400 ppm of lead solution is sodium chloride (31%) burnt grape (83%) s ground (99.71%)