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Volatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. [1] They are common and exist in a variety of settings and products, not limited to house mold , upholstered furniture , arts and crafts supplies, dry cleaned clothing, and cleaning supplies . [ 2 ]
Hydrofluorocarbons (HFCs), organic compounds that contain fluorine and hydrogen atoms, are the most common type of organofluorine compounds. They are commonly used in air conditioning and as refrigerants [5] in place of the older chlorofluorocarbons such as R-12 and hydrochlorofluorocarbons such as R-21.
Dioxins and dioxin-like compounds (DLCs) are a group of chemical compounds that are persistent organic pollutants (POPs) in the environment. They are mostly by-products of burning or various industrial processes or, in the case of dioxin-like PCBs and PBBs , unwanted minor components of intentionally produced mixtures.
The stability and lipophilicity of organic compounds often correlates with their halogen content, thus polyhalogenated organic compounds are of particular concern. [1] They exert their negative effects on the environment through two processes: long range transport, which allows them to travel far from their source, and bioaccumulation, which ...
Perfluoroaromatic compounds are relatively volatile for their molecular weight, with melting and boiling points similar to the corresponding aromatic compound, as the table below shows. They have high density and are non-flammable. For the most part, they are colorless liquids. Unlike the perfluoralkanes, they tend to be miscible with common ...
Use of certain chloroalkanes as solvents for large scale application, such as dry cleaning, have been phased out, for example, by the IPPC directive on greenhouse gases in 1994 and by the volatile organic compounds (VOC) directive of the EU in 1997. Permitted chlorofluoroalkane uses are medicinal only.
Many gases have toxic properties, which are often assessed using the LC 50 (median lethal concentration) measure. In the United States, many of these gases have been assigned an NFPA 704 health rating of 4 (may be fatal) or 3 (may cause serious or permanent injury), and/or exposure limits (TLV, TWA/PEL, STEL, or REL) determined by the ACGIH professional association.
Some petrochemical solvents are highly toxic and emit volatile organic compounds. Biobased solvents are usually more expensive, but ideally less toxic and biodegradable . Biogenic raw materials usable for solvent production are for example lignocellulose , starch and sucrose , but also waste and byproducts from other industries (such as ...