Source apportionment of trace contaminants in urban sewer catchments

Abstract

Sampling and analysis of Water Framework Directive priority chemicals were undertaken in nine urban catchments across the UK. Over 9000 samples were collected from a number of different catchment sources including tap water, domestic waste water, surface water runoff, trade discharges, town centre and light industrial estate wastewaters. Determinands included trace metals, polyaromatic hydrocarbons (PAHs), persistent organic pollutants and a number of common pharmaceuticals. Loads of the chemicals from each catchment entering the local wastewater treatment works (WwTW) were estimated and were shown to be relatively consistent between different catchments, after taking population into account. A Monte Carlo mixing model was used to combine the concentrations and flows from the different catchment sources and to predict concentrations and loads entering the WwTW. Based on the model output, the significance of the different sources could be evaluated. The study highlighted the importance of domestic wastewater as a source of contaminants, including metals and trace organic substances (such as ethylenediaminetetraacetic acid (EDTA), bisphenol A, nonylphenol and tributyl tin (TBT)). Concentrations in trade discharges were important in some locations in the case of nonylphenol, EDTA, TBT, as well as for some metals such as copper, zinc and nickel. Contributions to the total load from town centre and light industrial estate sources were generally less than 10% of the total.

Review of Antimicrobial Resistance in the Environment and Its Relevance to Environmental Regulators

“…Specifically, they reported an average loss of erythromycin, ofloxacin and oxytetracycline of 20, 74, and 51%, respectively, after iron-dosing (used to remove phosphorus), as compared to undosed primary treatment of -11, 19, and -4%, respectively. Concentrations of oxytetracycline within a river catchment receiving WWTP effluent varied 14-fold across nine WWTP sampling days, from 9.4 to 137 g/d (normalized to flow) (Comber et al, 2015), illustrating the variability in antibiotic consumption and the extent to which environmental exposures to antibiotics can fluctuate.…”

Aquatic exposures of chemical mixtures in urban environments: Approaches to impact assessment

“…The present compilation relies heavily on 3 major studies, the United Kingdom Water Industry Research monitoring data set (Comber et al ; WCA Environment ) and the studies of urban storm runoff in San Diego (Tetra Tech ) and in Sacramento and San Francisco (CA, USA; Ensminger and Kelley ). The UK results indicated that urban runoff generally contained high concentrations of nutrients (nitrogen and phosphorus), metals, and PAHs, often at concentrations considerably in excess of their Water Framework Directive adopted EQS values without consideration of dilution in the receiving water.…”

Active pharmaceutical ingredients entering the aquatic environment from wastewater treatment works: A cause for concern?

“…Some of results from this program have been reported previously (Gardner et al, 2012, Gardner et al;2013, Jones et al;Comber et al, 2014). The £140 million investment in the second phase of the CIP (labelled CIP2 in this work) program builds on the outputs from CIP1 but extends the range of WwTW monitored and the number of determinands in order to in some cases measure (for WFD priority substances and priority hazardous substances) and in some cases predict (for emerging chemicals such as APIs) the impact on receiving waters.…”