PARTICULATEMATTER

Molecular Weight: 0
Update Date: 2023-02-14 16:59:19

What is PARTICULATEMATTER?

Definition

General term for a mixture of fine solid particles and liquid droplets, such as dust, soot, smoke, mist, or fumes that are released into and move around in air, emissions, or smog.

Health Hazard

Epidemiological studies have consistently found an association between small increases in urban PM and health effects, including increased morbidity and mortality in people with respiratory and cardiac disease.

Properties of PARTICULATEMATTER

form

Particulate matter (PM) is not a specific chemical entity but a mixture of particles of different sizes, compositions, and properties. Examples include combustiongenerated particles such as diesel soot or fly ash; photochemically produced particles such as those found in urban haze; salt particles formed from sea spray; and soil-like particles from resuspended dust. Some particles are liquid, and some are solid. Others contain a solid core surrounded by liquid. Atmospheric particles contain inorganic ions, metallic compounds, elemental carbon, and organic compounds. The organic fraction is especially complex, containing hundreds of organic compounds. PM is called primary if it exists in the same chemical form in which it was emitted or generated. Secondary particles are formed from gases through chemical reactions in the atmosphere, involving atmospheric oxygen and water vapor; reactive species such as ozone (O3); radicals such as the hydroxyl (·OH) and nitrate (·NO3) radicals; and pollutants such as sulfur dioxide (SO2) and nitrogen oxides (NOx).
Particle size of PM is of considerable importance in relating ambient air concentrations to population morbidity and mortality. Routing ambient air monitoring studies before 1999 generally measured “thoracic” PM, namely, PM10 (upper size limited by a 50% cut at 10-mm aerodynamic diameter). Research and monitoring studies since 1999 have measured other fractions, but one of considerable significance is termed “fine” PM, namely, PM2.5 (upper size limited by a 50% cut point at 2.5-mm aerodynamic diameter.) An emerging measurement of importance is “ultrafine” particles, namely, PM0.1 (upper size limited by a 50% cut point at 0.1-mm aerodynamic diameter).

Safety information for PARTICULATEMATTER

Computed Descriptors for PARTICULATEMATTER

New Products

2-(2-Chlorophenyl)glycine Propiolic Acid 1-(3-Hydroxy-4-methoxyphenyl)-2-nitroethene (±)-amino(2-fluorophenyl)acetic acid trans-3-Benzyloxy-4-methoxy-beta-nitrostyrene 1-Pentadecanol 2,4-Dihydroxybenzaldehyde Dipropyl disulfide Pyrrolo[1,2-a]pyrimidine-6-carboxylic acid, 4,6,7,8-tetrahydro-4-oxo-, sodium salt (1:1), (6S) Obidoxime hydrochloride API 4 pentyn 1 ol N-Vinylformamide Methacrylate-PEG-Methacrylate, Mn:35000 2,4-Dihydroxyacetophenone 2-Chloro 5-Fluoro Pyridine Vasicinone 2-Chloroisonicotinic Acid Tween 80 or Polysorbate 80 2-Butyn-1-oL N-(4-Cyano-3-(trifluoromethyl)phenyl)-2-methyloxirane-2-carboxamide N-(4-fluoro-2-methoxy-5-nitrophenyl)-4-(1-methyl-1H-indol-3-yl)pyrimidin-2-amine Pirtobrutinib intd. 2-Pentyn-1-oL 4-Nitrobenzotrifluoride