THERMAL-DESORPTION OF ORGANIC-COMPOUNDS ASSOCIATED WITH SETTLED HOUSEHOLD DUST

Settled household dust samples were collected from twelve dwellings in urban areas during an annual winter heating period. Emission of compo unds from settled household dust was analyzed under simulated hot surf ace conditions with a temperature range of 50-300-degrees-C. The compo unds were analyzed and identified by thermal desorption-gas chromatogr aphic-mass spectrometric technique. The organic emission from househol d dust was relatively low at temperatures below 70-degrees-C, increase d appreciably above 100-degrees-C, and gained in strength at temperatu res above 200-degrees-C. Desorption of adsorbed compounds is the main contribution to emissions, but at higher temperatures the thermal degr adation seems to affect also the quantity and the quality of the emiss ions. The organic composition of household dust was found to be equal in quality at different sampling sites; the emissions consist of mainl y aliphatic aldehydes (C6-C13), aliphatic carboxylic acids and their e sters (C8-C18), n-alkanes (C16-C30) and phthalates. Phosphate esters, branched alkanes, n-alkenes, n-alkanones, monoterpenes, aromatic hydro carbons, and aromatic and aliphatic alcohols were also well represente d groups in household dust samples. The potential sources of identifie d compounds are discussed.