Emission factor estimation of ca. 160 emerging organic microcontaminants by inverse modeling in a Mediterranean river basin (Llobregat, NE Spain)

Abstract

Starting from measured river concentrations, emission factors of 158 organic compounds out of 199 analyzed belonging to different groups of priority and emerging contaminants [pesticides (25), pharmaceuticals and hormones (81), perfluoroalkyl substances (PFASs) (18), industrial compounds (12), drugs of abuse (8) and personal care products (14)] have been estimated by inverse modeling. The Llobregat river was taken as case study representative of Mediterranean rivers. Industrial compounds and pharmaceuticals are the dominant groups (range of 10(4) mg·1000 inhab(-1)·d(-1)). Personal care products, pesticides, PFASs and illegal drugs showed a load approximately one order of magnitude smaller. Considered on a single compound basis industrial compounds still dominate (range of ca. 10(3) mg·1000 inhab(-1)·d(-1)) over other classes. Generally, the results are within the range when compared to previously published estimations for other river basins. River attenuation expressed as the percentage fraction of microcontaminants eliminated was quantified. On average they were around 60-70% of the amount discharged for all classes, except for PFASs, that are poorly eliminated (ca. 20% on average). Uncertainties associated with the calculated emissions have been estimated by Monte-Carlo methods (15,000 runs) and typically show coefficients of variation of ca. 120%. Sensitivities associated with the various variables involved in the calculations (river discharge, river length, concentration, elimination constant, hydraulic travel time and river velocity) have been assessed as well. For the intervals chosen for the different variables, all show sensitivities exceeding unity (1.14 to 3.43), tending to amplify the variation of the emission. River velocity and basin length showed the highest sensitivity value. Even considering the limitations of the approach used, inverse modeling can provide a useful tool for management purposes facilitating the quantification of release rates of chemicals into the aquatic environment.

Improving degradation of emerging organic compounds by applying chaotic advection in Managed Aquifer Recharge in randomly heterogeneous porous media

“…These compounds are associated with chemicals used in urban environments (pharmaceuticals, personal care, or life style products), industrial areas (additives, surfactants, flame retardants), and agricultural zones (pesticides, antibiotics used in veterinary activities). EOCs have been detected in all types of water bodies, from surface [Banjac et al, 2015;Navarro-Ortega et al, 2012] to subsurface [Jurado et al, 2012;L opez-Serna et al, 2013].…”

A high-precision sampling scheme to assess persistence and transport characteristics of micropollutants in rivers

“…A novel threat to aquatic ecosystems is posed by the increasing number and amount of xenobiotics released into the environment (Banjac et al, 2015;Jekel et al, 2015;Ternes, 2007). These 'emerging pollutants', emitted by all of us in everyday life, comprise -among others -pharmaceuticals and personal care products (Carmona et al, 2014;KasprzykHordern et al, 2009;Ternes et al, 2004), pesticides (Köck-Schulmeyer et al, 2013;Sandstrom et al, 2005), and flame retardants (Meyer and Bester, 2004;Pang et al, 2013).…”

Pharmaceuticals and personal care products in waters: occurrence, toxicity, and risk

“…A number of modeling programs have been developed. PhATE (USA) and GREAT-ER are two exposure models (Banjac et al 2015; Caldwell et al 2014). In addition, the US EPA ECOSAR™ model estimates the short-term and long-term toxicities of chemicals to freshwater and saltwater organisms.…”