First assessment of triclosan, triclocarban and paraben mass loads at a very large regional scale: Case of Paris conurbation (France)

The objective of this study was to examine the occurrence of parabens (5 congeners), triclosan (TCS) and triclocarban (TCC) at the scale of the Parisian sewer network and to provide representative knowledge on these compounds in France for a large area. For this purpose and in collaboration with the Parisian public sanitation service (SIAAP) in charge of the collect and treatment of the Parisian wastewater, this study focused on seven main sewer trunks of the Paris conurbation, accounting for 1900000m³d^-1, i.e., about 8million inhabitants. Concentrations lying in the 2000-20000ngl^-1 ranges were found in wastewater, confirming the ubiquity of parabens, TCS and TCC in our environment and household products. Parabens (>97%) and to a lesser extent TCS (68% in median) were mainly associated to the dissolved fraction, as demonstrated by low K_D and K_OC values. For the first time, this study also evaluated the pollutant mass loads per population equivalent (PE) of parabens, TCS and TCC at the large and representative scale of the Parisian conurbation. Hence, the median mass loads varied from 176 to 3040μgPE^-1d^-1 for parabens and from 26 to 762μgPE^-1d^-1 for TCS and TCC. Based on these results and according to the assumptions done, the extrapolation of the mass loads at the national scale pointed out an annual mass loads between 51.8 and 100.7ty^-1 for methyl paraben (MeP) and between 11.2 and 23.5ty^-1 for TCS. Mass loads per equivalent habitant and national mass loads are both extremely relevant and innovative data. Contrary to other countries, such data are nowadays rather difficult to gain in France and neither enquiry nor database provides access to information on the use and production of these chemicals. Since cosmetic industries are voluntarily and fully engaged in the substitution of parabens, triclosan and triclocarban in personal care product, this study could constitute a "time reference status" which could be used as a basis for future monitoring.