Related topics: water · pollution

Total annihilation for supermassive stars

A renegade star exploding in a distant galaxy has forced astronomers to set aside decades of research and focus on a new breed of supernova that can utterly annihilate its parent star—leaving no remnant behind. The signature ...

Distant 'heavy metal' gas planet is shaped like a football

The scorching hot exoplanet WASP-121b may not be shredding any heavy metal guitar riffs, but it is sending heavy metals such as iron and magnesium into space. The distant planet's atmosphere is so hot that metal is vaporizing ...

Using organisms to decontaminate soil

The German Ministry of Education and Research is funding a long-term soil remediation project run by the University of Jena. The project is to investigate and test biological methods for remediating soils contaminated with ...

Magnetic 'springs' break down marine microplastic pollution

Plastic waste that finds its way into oceans and rivers poses a global environmental threat with damaging health consequences for animals, humans, and ecosystems. Now, using tiny coil-shaped carbon-based magnets, researchers ...

Researchers push for better policies around toxic chemicals

From high levels of lead found in school drinking water to industry sites releasing toxic heavy metals into the air, over 40 years of regulations in the United States have failed to protect human and environmental health ...

S.African green groups sue government over air pollution

Two South African environmental groups are suing the government over air pollution in the northeastern province of Mpumalanga, where 83 percent of the country's coal is mined, their lawyer said Monday.

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Heavy metal (chemistry)

A heavy metal is a member of an ill-defined subset of elements that exhibit metallic properties, which would mainly include the transition metals, some metalloids, lanthanides, and actinides. Many different definitions have been proposed—some based on density, some on atomic number or atomic weight, and some on chemical properties or toxicity. The term heavy metal has been called "meaningless and misleading" in an IUPAC technical report due to the contradictory definitions and its lack of a "coherent scientific basis". There is an alternative term toxic metal, for which no consensus of exact definition exists either. As discussed below, depending on context, heavy metal can include elements lighter than carbon and can exclude some of the heaviest metals. Heavy metals occur naturally in the ecosystem with large variations in concentration. Nowadays anthropogenic sources of heavy metals, i.e. pollution, have been introduced to the ecosystem. Waste derived fuels are especially prone to contain heavy metals so they should be a central concern in a consideration of their use.

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