Summary
A toxic heavy metal is any relatively dense metal or metalloid that is noted for its potential toxicity, especially in environmental contexts. The term has particular application to cadmium, mercury and lead, all of which appear in the World Health Organization's list of 10 chemicals of major public concern. Other examples include manganese, chromium, cobalt, nickel, copper, zinc, silver, antimony and thallium. Heavy metals are found naturally in the earth. They become concentrated as a result of human caused activities and can enter plant and animal (including human) tissues via inhalation, diet, and manual handling. Then, they can bind to and interfere with the functioning of vital cellular components. The toxic effects of arsenic, mercury, and lead were known to the ancients, but methodical studies of the toxicity of some heavy metals appear to date from only 1868. In humans, heavy metal poisoning is generally treated by the administration of chelating agents. Some elements otherwise regarded as toxic heavy metals are essential, in small quantities, for human health. Heavy metals are found naturally in the earth, and become concentrated as a result of human activities, or, in some cases geochemical processes, such as accumulation in peat soils that are then released when drained for agriculture. Common sources are mining and industrial wastes; vehicle emissions; motor oil; fuels used by ships and heavy machineries; construction works; fertilisers; pesticides; paints; dyes and pigments; renovation; illegal depositing of construction and demolition waste; open top roll-off dumpster; welding, brazing and soldering; glassworking; concrete works; roadworks; use of recycled materials; DIY metal projects; burning of joss paper; open burning of waste in rural area; contaminated ventilation system; food contaminated by the environment or by the packaging; armaments; lead-acid batteries; electronic waste recycling yard; treated woods; aging water supply infrastructure; and microplastics floating in the world's oceans.
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related lectures (5)
Metal Speciation
Explores metal speciation in the environment, covering reactions, properties, challenges, and biological aspects.
Materials Science of Cycling: Frame, Tires, and Accessories
Delves into the materials science behind cycling, covering bike frame alloys, tire materials, and accessories.
Show more
Related publications (89)

Electrochemical sensors modified with iron oxide nanoparticles/ nanocomposites for voltammetric detection of Pb (II) in water: A review

Sandro Carrara

Permissible limits of Pb 2+ in drinking water are being reduced from 10 mu gL -1 to 5 mu gL -1 , which calls for rapid, and highly reliable detection techniques. Electrochemical sensors have garnered attention in detection of heavy metal ions in environmen ...
Cell Press2024

Development of a magnetic calcium-alginate hydrogel-sphere encapsulated with Fe-Mn-Zr ternary metal composite for heavy metal adsorption

Yi Yang, Xinyi Huang

Heavy metal contamination has become one of the greatest global environmental problems. In this study, a magnetic calcium-alginate hydrogel-sphere encapsulated with Fe-Mn-Zr ternary-metal composite (MCHETC) was prepared through a combined co-precipitation ...
2023

Lead immobilization for environmentally sustainable perovskite solar cells

Michael Graetzel, Antonio Abate, Hui Zhang

Lead halide perovskites are promising semiconducting materials for solar energy harvesting. However, the presence of heavy-metal lead ions is problematic when considering potential harmful leakage into the environment from broken cells and also from a publ ...
NATURE PORTFOLIO2023
Show more
Related concepts (16)
Mercury poisoning
Mercury poisoning is a type of metal poisoning due to exposure to mercury. Symptoms depend upon the type, dose, method, and duration of exposure. They may include muscle weakness, poor coordination, numbness in the hands and feet, skin rashes, anxiety, memory problems, trouble speaking, trouble hearing, or trouble seeing. High-level exposure to methylmercury is known as Minamata disease. Methylmercury exposure in children may result in acrodynia (pink disease) in which the skin becomes pink and peels.
Heavy metals
Heavy metals are generally defined as metals with relatively high densities, atomic weights, or atomic numbers. The criteria used, and whether metalloids are included, vary depending on the author and context. In metallurgy, for example, a heavy metal may be defined on the basis of density, whereas in physics the distinguishing criterion might be atomic number, while a chemist would likely be more concerned with chemical behaviour. More specific definitions have been published, none of which have been widely accepted.
Minamata disease
Minamata disease is a neurological disease caused by severe mercury poisoning. Signs and symptoms include ataxia, numbness in the hands and feet, general muscle weakness, loss of peripheral vision, and damage to hearing and speech. In extreme cases, insanity, paralysis, coma, and death follow within weeks of the onset of symptoms. A congenital form of the disease affects fetuses in the womb, causing microcephaly, extensive cerebral damage, and symptoms similar to those seen in cerebral palsy.
Show more