Use of DREAM to assess relative risks of presence of pharmaceuticals and personal care products from a wastewater treatment plant

Concerns related to environmental risks associated with pharmaceuticals and personal care products (PPCPs) have led researchers to seek methods for assessing and monitoring these contaminants in the aquatic environment. Identifying and validating risk assessment tools that can evaluate ecological concerns and risks associated with PPCPs is critical. Herein, the suitability of a dose-related risk and effect assessment model, which estimates predicted environmental concentrations and allowed comparisons with predicted no effect concentrations determined, in combination with in vitro analyses of the whole effluent toxicity, was verified for the characterization of a PPCP hazard. Concentrations of the most utilized PPCPs in Norway were measured in influent and effluent samples and used to parameterize the fate model.

Greater than 90% removal was attained for 12 out of 22 detected PPCPs. Removal was not dependent on the class or the concentration of the specific substance and varied between 12% and 100%. The PPCPs detected in the discharged wastewater were utilized to assess individual contributions to the risk of the effluent, and no risk was identified for the targeted 30 PPCP. The simulations provided valuable information regarding the discharge plume distribution over time, which can aid planning of future environmental monitoring investigations.

Bioassays (using fish liver cells, PLHC-1) were used for assessing overall effluent toxicity, through cell viability, production of reactive oxygen species, and ethoxyresorufin-O-deethylase (EROD) activities.

The present study may allow regulators to use risk-based strategies over removal criteria for monitoring studies and confirms the importance to take PPCP contamination into consideration when establishing environmental regulations.