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Biomagnification is the buildup of concentration of a substance (x) in a food chain. For example the DDT concentration in parts per million increases with trophic level. Concentrations build up in organism's fat and tissue. Predators accumulate higher levels than prey. Biological magnification often refers to the process whereby substances such ...
Arsenic is the 53rd most abundant element in the Earth's crust, comprising about 1.5 parts per million (0.00015%). [ 43 ] Typical background concentrations of arsenic do not exceed 3 ng/m 3 in the atmosphere; 100 mg/kg in soil; 400 μg/kg in vegetation; 10 μg/L in freshwater and 1.5 μg/L in seawater. [ 44 ]
Arsenic biochemistry. S-Adenosylmethionine, a source of methyl groups in many biogenic arsenic compounds. Arsenic biochemistry refers to biochemical processes that can use arsenic or its compounds, such as arsenate. Arsenic is a moderately abundant element in Earth's crust, and although many arsenic compounds are often considered highly toxic ...
Arsenic poisoning. Arsenic poisoning (or arsenicosis) is a medical condition that occurs due to elevated levels of arsenic in the body. [ 4 ] If arsenic poisoning occurs over a brief period of time, symptoms may include vomiting, abdominal pain, encephalopathy, and watery diarrhea that contains blood. [ 1 ]
v. t. e. The arsenic (As) cycle is the biogeochemical cycle of natural and anthropogenic exchanges of arsenic terms through the atmosphere, lithosphere, pedosphere, hydrosphere, and biosphere. Although arsenic is naturally abundant in the Earth's crust, long-term exposure and high concentrations of arsenic can be detrimental to human health.
Marsh test. The Marsh test is a highly sensitive method in the detection of arsenic, especially useful in the field of forensic toxicology when arsenic was used as a poison. It was developed by the chemist James Marsh and first published in 1836. [1] The method continued to be used, with improvements, in forensic toxicology until the 1970s. [2]
Dioxins are extremely stable and consequently tend to accumulate in the food chain. They are eliminated very slowly in animals, e.g. TCDD has a half-life of 7 to 9 years in humans. [4] [7] [8] Incidents of contamination with PCBs are often reported as dioxin contamination incidents since these are of most public and regulatory concern. [9] [1]
A recent study by the Center for Environmental Health (CEH) has revealed high levels of metal arsenic in two brands of bottled water sold by Whole Foods and Walmart. Last month, the organization ...