Synthetic Musk Fragrances in a Conventional Drinking Water Treatment Plant with Lime Softening

摘要

Synthetic musk fragrances are common personal care product additives and wastewater contaminants that are routinelydetected in the environment. This study examines the presence of eight synthetic musk fragrances [7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), 1,3,4,6,7,8-hexahydro-4,6,6,7,8-hexamethylcyclopenta-y-2-benzopyran (HHCB), 5-acetyl-1,1,2,6-tetramethyl-3-i so-propylindane (ATM, 4-acetyl-1,1-dimethyl-6-tert-butylindane (ADBI), 6-acetyl-1,1,2,3,3,5-hexamethylindane(AHMI), 6,7-dihydro-1,1,2,3,3,-pentamethyl-4-(5H)-indanone (DPMI), 1-tert-butyl-3,5-dimethyl-2,4,6-trinitrobenzene (musk xylene),and 4-tert-butyl-3,5-dinitro-2,6-dimethylacetophenone (musk ketone)] in source water and the removal of these compounds as they flowthrough a Midwestern conventional drinking water plant with lime softening. The compounds were measured in water, waste sludge, andair throughout the plant. HHCB and AHTN were detected in 100% of the samples and at the highest concentrations. A mass balance onHHCB and AHTN was performed under warm and cold weather conditions. The total removal efficiency for HHCB and AHTN, whichaveraged between 67-89%, is dominated by adsorption to water softener sludge and its consequent removal by sludge wasting and mediafiltration. Volatilization, chlorine disinfection, and the disposal of backwash water play a minor role in the removal of both compounds.As a result of inefficient overall removal, HHCB and AHTN are a constant presence at low levels in finished drinking water.