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Indian Institute of Science (IISc) researchers have developed a novel remediation process for removing heavy metal contaminants such as arsenic from groundwater
The three-step method, which is patent-pending, also ensures that the removed heavy metals are disposed of in an environment-friendly and sustainable manner, instead of sending untreated heavy metal-rich sludge to landfills from where they can potentially re-enter groundwater
Heavy metal contaminants
Heavy metals are generally defined as metals with relatively high densities, atomic weights, or atomic numbers.
Heavy metals normally occur in nature and are essential to life but can become toxic through accumulation in organisms.
Arsenic, cadmium, chromium, copper, nickel, lead and mercury are the most common heavy metals which can pollute the environment.
Mercury, lead and cadmium are of greatest concern because of their ability to travel long distances in the atmosphere
Sources of heavy metals include mining, industrial production (foundries, smelters, oil refineries, petrochemical plants, pesticide production, chemical industry), untreated sewage sludge and diffuse sources such as metal piping, traffic and combustion by-products from coal-burning power stations
Mercury exposure can harm the brain, heart, kidneys, lungs, and immune system of people of all ages
Mercury accumulation in fish may harm the fish and other animals that consume them, thus affecting the ecosystem
Lead may, cause neurodevelopmental effects in children, even at low levels of exposure.
Other effects include cardiovascular, renal, gastrointestinal, hematological and reproductive effects
Cadmium is toxic to humans and exposure can cause pulmonary irritation, kidney disease, bone weakness and possibly lung, prostate, and kidney cancer.
Food and cigarette smoke are the largest potential sources of cadmium exposure for the general population
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