A Snapshot on the Occurrence and Risk Assessment of Organic Pollutants in an Urban River

A snapshot screening was carried out in an urban river at the end of a dry period in the water and sediments to assess the presence and environmental risk for the following CECs: paracetamol, ibuprofen, diclofenac, clofibric acid, carbamazepine, ofloxacin, caffeine, tonalide, galaxolide, and bisphenol-A. Concomitantly, the occurrence and environmental risk of sixteen PAHs congeners, six indicator PCBs, and twelve dioxin-like PCBs were evaluated in sediments. The most abundant and ubiquitous CECs were bisphenol A (BPA) and caffeine, and the total contents in the surface water varied between 90.95-212.18 and 3.17-167.38 ng center dot L-1, respectively. The concentrations found in lixiviates ranged from 134.94-772.85 (BPA) and 14.43-92.60 ng center dot L-1 (caffeine). Other CECs were detected in lower concentrations, and their presence varied between sampled sites. Values of total PAHs congeners in sediment varied between 10.39-52.91 ng center dot g(-1) dw. The majority of the detected PAHs seem to have a pyrolitic origin with a small petrogenic contribution. Total PCBs' concentrations ranged from 5.06 to 6.13 ng center dot g(-1) dw. Despite the relatively low concentration of most of the detected compounds, the overall environmental risk, considering the screened compounds altogether, cannot be considered negligible. The obtained results are discussed in terms of other data available (though highly dispersed) in the literature. A four-color alert system is included to inform about the level of risk associated with the amount of each CEC, PAH, and PCB.

Automated summary

A snapshot screening was conducted in an urban river to evaluate the presence and environmental risk of certain contaminants in the water and sediments. The most commonly detected contaminants were bisphenol A (BPA) and caffeine. The overall environmental risk, considering all the screened compounds together, was found to be significant. The results are discussed in relation to available literature data, and a four-color alert system is included to inform about the risk levels of specific contaminants.