Biodegradation and Partitioning of Triclosan from a model Municipal Waste Water Treatment Plant

Biodegradation and Partitioning of Triclosan from a model Municipal Waste Water Treatment Plant

Triclosan is the commercial name of 5-chloro-2-(2,4-dichlorophenoxy)phenol), an antibacterial and antifungal compound used in a variety of household products. Even at low levels, 0.03 to 0.15% by weight, Triclosan is effective at killing bacteria. Products include soaps, toothpaste, shampoos, tissue paper, and cosmetics. There is a growing trend among manufacturers of diverse products to add the antimicrobial as a marketing edge regardless of its utility. Recent studies indicate triclosan is more persistent in the environment than initially reported. In order to study the effectiveness of wastewater treatment on the degradation of triclosan, a small scale water treatment process was duplicated. The biodegradation and partitioning of the triclosan remaining between the aqueous phase and the solid phase sludge was determined by GC/MS. 2.0 + 0.3 % of the original triclosan remained in the aqueous phase however, 74.9 + 11.4% partitioned to the solid (sludge) phase. Overall, the treatment process only degraded 23.1 + 6.2% of the triclosan initially present. A common practice is to use the sludge from wastewater treatment as an agricultural fertilizer. A potential ramification of the biocide is the impact the triclosan will have on the soil microbes and the potential development of resistant to the pesticide when the sludge is used in this manner.