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Highly Toxic: a gas that has a LC 50 in air of 200 ppm or less. [2] NFPA 704: Materials that, under emergency conditions, can cause serious or permanent injury are given a Health Hazard rating of 3. Their acute inhalation toxicity corresponds to those vapors or gases having LC 50 values greater than 1,000 ppm but less than or equal to 3,000 ppm ...
Not all heavy metals are toxic and some toxic metals are not heavy. [5] Elements often discussed as toxic include cadmium, mercury and lead, [6] all of which appear in the World Health Organization's list of 10 chemicals of major public concern. [7] Other examples include chromium and nickel, [8] thallium, bismuth, arsenic, antimony and tin. [4]
Many metals, particularly heavy metals are toxic, but some are essential, and some, such as bismuth, have a low toxicity. Metals in an oxidation state abnormal to the body may also become toxic: chromium(III) is an essential trace element, but chromium(VI) is a carcinogen. Only soluble metal-containing compounds are toxic.
The term "environmental toxin" can sometimes explicitly include synthetic contaminants [26] such as industrial pollutants and other artificially made toxic substances. As this contradicts most formal definitions of the term "toxin", it is important to confirm what the researcher means when encountering the term outside of microbiological contexts.
The most important chemical reactions of phosphoryl halides is the hydrolysis of the bond between phosphorus and the fluorine atom. This P-F bond is easily broken by nucleophilic agents, such as water and hydroxide. At high pH, sarin decomposes rapidly to nontoxic phosphonic acid derivatives.
Most of the victims died from inhaling poisonous gases, including carbon monoxide. After the fire, the technical institution INTI found that the level of toxicity due to the materials and volume of the building was 225 ppm of cyanide in the air. A lethal dose for rats is between 150 ppm and 220 ppm, meaning the air in the building was highly toxic.
This is the list of extremely hazardous substances defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. § 11002).The list can be found as an appendix to 40 CFR 355. [1]
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. [1] Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell (cytotoxicity) or an organ such as the liver (hepatotoxicity).