Occurrence And Distribution Of Polycyclic Musks In Wastewater Treatment Plants And The Preliminary Study On Their Removal

Synthetic musks, including nitro musks, polycyclic musks and macrocyclic musks, are inexpensive substitutes for natural musks. Polycyclic musks are representatives of synthetic musks. They are widespread used as fragrance materials in detergent, soap, cosmetic, perfume, shampoo, body lotion, personal care products, etc. These compounds enter domestic sewage after application.Polycyclic musks exhibit same properties, hydrophobic and lipophilic, bioaccumulation as polycyclic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). These nonpolar compounds prefer to be adsorbed to organic particles in water, are persistent in environmental and show weak estrogenic activity.Domestic sewage and industrial wastewater are treated in Wastewater Treatment Plants (WWTPs). Polycyclic musks enter environmental through sewage sludge (application to land, burial underground) and effluent from WWTPs. At last, polycyclic musks are bioaccumulated into biotas and human body through food chain. Researchers in environmental field have detected synthetic musks in almost every apartment of environmental, such as surface water, seawater, sediment, air and biota samples. Polycyclic musks have also been detected in human adipose tissues, blood and breast milk.Hitherto, little is known about the distribution and extent of possible contamination with the polycyclic musks in China, although China is one of the main countries producing synthetic musks. The aim of this study is developed a rapid, economic analytical method for polycyclic musks from solid matrix and from water.Sewgae sludge samples were collected from three municipal wastewater treatment plants (GD1, GD2, GD3), two household products plants (A, B) and one food plant (C). GD1 serves 700 thousand inhabitants with a daily capacity of 300,000 tons, of which 60% is domestic sewage, and 40% from industrial wastewaters. GD2 serves 1200 thousand inhabitants with a daily capacity of 220,000 tons, which primarily treats domestic sewage. GD3 serves 60 thousand inhabitants with a daily capacity of 30,000 tons and receives 30% domestic wastewater and 70% industrialwastewater including effluents from household products production.Polycyclic musks were Soxhlet extracted, separated and analyzed from these sludge samples using GC and GC-EI-MS. DPMI, ADBI, HHCB, AHTN are found in all samples, and ATII is not found in any sample. AHMI is detected in 5 out of 6 samples. HHCB and AHTN are the two major polycyclic musks found in highest concentrations in sludge. The sludge from 3 municipal wastewater treatment plants, contains HHCB, AHTN, ADBI, DPMI at concentrations between 5.416-21.214, 0.715-6.195, 0.192-0.210 and 0.599-2.870 mg/kg (dry), respectively. The highest concentration is found in sludge from a household products plant at 703.681 mg HHCB /kg (dry). The lowest concentrations of HHCB and AHTN are found in sludge from the food plant. The results indicate that, a) HHCB and AHTN are the two main components of polycyclic musks detected in sludge, b) there are two sources of polycylic musks: domestic sewage and industrial wastewater.The distribution of polycyclic musks in wastewater are analysed according to the treatment procedure in one municipal WWTP. The results indicate that influent (including 70% industrial wastewater and 30% domestic sewage) contains considerable concentration of polycyclic musks, most of which were adsorbed to the particles in wastewater, for example, more than 88% of HHCB and 82% of AHTN were adsorbed to the particles; The characteristic of distribution of polycyclic musks in primary effluent is similar to that in the influent. The main removal route of polycyclic musks from wastewater is adsorption to the organic particles in sludge, while oxidative degradation in activated sludge plays a minor role in the removal.