Synthetic musk fragrances in urban and rural air of Iowa and the Great Lakes

Synthetic musk fragrances are semivolatile organic compounds used to scent a variety of household and personal care products. In this study, six polycyclic musk fragrances (HHCB, AHTN, ATII, AHMI, ADBI, and DPMI) and two nitro musk fragrances (musk xylene and musk ketone) were evaluated in 181 air samples collected at urban, suburban, and rural sites in Iowa and the Great Lakes. This is the largest reported study of the compounds in ambient air and reveals the ubiquitous nature of these environmental contaminants. HHCB and AHTN were detected most frequently and at the highest concentrations at all sites. Synthetic musk fragrance concentrations were highest in urban locations, including Milwaukee, WI (previously reported) and an urban location in Cedar Rapids, IA. Urban concentrations of HHCB and AHTN are on the order of 1–5 ng m−3 and background terrestrial concentrations are about an order of magnitude less. In rural Iowa, the concentrations and frequency of detection of the synthetic musk fragrances are comparable to (and often greater than) gas-phase pesticide concentrations. The concentrations measured at the suburban location in Iowa City, IA and over the Lakes Erie, Ontario, and Michigan were generally intermediate of those measured at the rural and urban locations. Concentrations of HHCB and AHTN were correlated with temperature at the sampling sites in Iowa.