Mercury (Hg)
Definition
Three toxic forms: elemental (vapour from broken thermometers, dental amalgam), inorganic salts (mercuric chloride, corrosive sublimate), and organic (methylmercury from biomagnification, ethylmercury from thimerosal). Targets kidneys and central nervous system. Minamata Bay outbreak (Japan, 1956) was methylmercury.
- Forms
- Elemental, inorganic salts, organic
- Organic example
- Methylmercury, ethylmercury
- Target organs
- Kidneys, central nervous system
- Notable outbreak
- Minamata Bay, Japan, 1956
Common questions
Why does the chemical form of mercury change how it poisons the body?+
Elemental mercury vapour is absorbed mainly through the lungs and affects the central nervous system, inorganic salts like mercuric chloride are corrosive and damage the kidneys directly, and organic forms such as methylmercury cross the blood-brain barrier efficiently and bioaccumulate up the food chain, so exposure route and chemical form both matter for diagnosis.
What made the Minamata Bay outbreak significant to toxicology as a field?+
It was one of the first large-scale demonstrations that industrial methylmercury discharge could biomagnify through fish and cause severe, irreversible neurological disease in a human population, which shaped later understanding of organic mercury's environmental and biomagnification pathway.
Related terms
- Arsenic (As)
- Metalloid; trivalent arsenite (As III) is 60 times more toxic than pentavalent arsenate (As V). Thiol-group blocker that poisons mitochondrial enzymes (pyruvate...
- Dry Ashing
- Viscera or hair is dried and incinerated in a muffle furnace at 450 to 550 degrees Celsius. Inorganic ash is dissolved in...
- Hydride Generation (HG-AAS)
- Sensitivity booster for As, Sb and Se. Sample plus NaBH4 in acid liberates AsH3 / SbH3 / SeH2 gas, which is swept...
- Lead (Pb)
- Cumulative neurotoxin from chronic occupational exposure (battery recycling, smelter work), leaded paint, contaminated cosmetics (low-grade sindoor, surma, kohl), and adulterated Ayurvedic preparations....
- Marsh Test (1836)
- Confirmatory test for arsenic devised by James Marsh after the Bodle case (1832), in which Marsh was unable to convince a jury...
- Reinsch Test
- Classical screen for arsenic, antimony, mercury and bismuth. A clean copper strip is immersed in the acidified sample (concentrated HCl, near-boiling) for...
- Thallium (Tl)
- The 'poisoner's poison' because thallium sulphate is tasteless, odourless and colourless. Substitutes for potassium in cellular transport. Alopecia at 2 to 3...
- Wet Digestion
- Viscera is digested with HNO3 + H2SO4 + HClO4 (or HNO3 + H2O2) at controlled temperature. Closed-vessel microwave-assisted digestion in Teflon bombs...