SVOCs

Semivolatile organic compounds (SVOCs) are organic chemicals with relatively low vapor pressures and high boiling points compared with volatile organic compounds (VOCs). At typical environmental temperatures, SVOCs do not fully volatilize and tend to partition between air, surfaces, soils, and sediments. They are often persistent, can accumulate in soils and sediments, and may bioaccumulate in organisms through long-range transport and exposure via multiple pathways.

Common SVOCs include phthalates used as plasticizers; flame retardants such as polybrominated diphenyl ethers; organochlorine pesticides; polychlorinated biphenyls; and many polycyclic aromatic hydrocarbons. SVOCs originate from consumer products, industrial processes, combustion, and atmospheric deposition. They can be released indoors from building materials, furnishings, electronics, and textiles, contributing to indoor dust reservoirs that serve as exposure sources.

Environmental fate and exposure: SVOCs resist degradation to varying degrees, persist in the environment, and are subject to sorption to organic matter; they may undergo long-range transport. In air, water, soil, and sediments they partition among phases and can bioaccumulate in wildlife and humans, mainly via inhalation of particles, ingestion of contaminated dust or food, and dermal contact. Monitoring often includes air particulates, dust, water, soil, and biological tissues.

Measurement and regulation: Analysis commonly uses gas chromatography–mass spectrometry after solvent extraction or solid-phase extraction. The term SVOC is not tied to a single chemical class; it is defined by volatility and molecular properties and thus overlaps with VOCs and with more persistent organics.