Human Health Risk Assessment for Pharmaceuticals in the Environment: Existing Practice, Uncertainty, and Future Directions

Pharmaceutical Drugs in Aquatic Environment and their Toxic Effect on <i>Pangasius sp.</i> : An Overview

One of the fastest-growing freshwater fish varieties is the Pangasius sp., which has a great capability for production and export growth. When Pangasius sp. is exposed to substances such as diclofenac, phenol, quinolones, sulfonamides, and tetracycline, even at low environmental exposure levels the fish tissue can develop chronic risk, genetic abnormalities, and histopathological changes. They come into contact with these antibiotics mostly through the discharge of pharmaceutical industry effluents, which contain antibiotic residues that are not been completely eliminated by wastewater treatment, thereby posing environmental concerns when released into aquatic ecosystems. The main objective of this review paper is to study the effect of the concentration of pharmaceutical drugs, farming techniques, and various substitutes for antibiotics that can be utilized to enhance the growth performance of Pangasius sp. Few studies conducted on toxicity demonstrated that increased mucus production in the gills and intestines, histological abnormalities in the liver and skin, and impaired immunoglobulin production have all been linked to sublethal phenol concentrations in fish. The consumption of these contaminated Pangasius sp. can raise various human health concerns. Therefore, exposure of Pangasius sp. to the detrimental pharmaceutical drug from industrial effluent must be held serious concern. Further research is required to conserve human health and the ecosystem.

Do pharmaceuticals reach and affect the aquatic ecosystems in Brazil? A critical review of current studies in a developing country

Pharmaceutical residues are not completely removed in wastewater treatment plants (WWTPs) becoming contaminants in aquatic ecosystems. Thereby, it is important to investigate their concentrations in the environment and the possible consequences of their occurrence, including for human health. Here, we briefly reviewed the paths of pharmaceuticals to reach the environment, their behavior and fate in the environment, and the possible consequences of their occurrence. Moreover, we synthetized all the studies about the detection of pharmaceuticals in Brazilian water bodies and the available ecotoxicological knowledge on their effects. In this study, when we compare the data found on these compounds worldwide, we observed that Brazilian surface waters present considerable concentrations of 17α-ethinylestradiol, 17β-estradiol, and caffeine. In general, concentrations found in aquatic systems worldwide seems to be low; however, ecotoxicological tests showed that even these low concentrations can cause sublethal effects in biota. The knowledge about the effects of continuous exposure and mixtures is sparse. In summary, new research is urgently required about the effects of these compounds in biota-including long-term exposition and mixture tests-and on specific technologies to remove these compounds in water bodies and WWTPs, besides the introduction of new policies for pharmaceutical use.

Occurrence and environmental implications of pharmaceuticals in Chinese municipal sewage sludge

The presence of pharmaceuticals in aquatic environment has become a topic of concern because of their potential adverse effects on human health and wildlife species. A total of 45 dewatered sewage sludge samples were collected throughout China and analyzed for 30 commonly consumed pharmaceutical residues. Ofloxacin was found to be the dominant contaminant with concentrations up to 24760 μg kg(-1), followed by oxytetracycline (5280 μg kg(-1)), norfloxacin (5280 μg kg(-1)) and ketoprofen (4458 μg kg(-1)). The concentration of pharmaceutical residues varied greatly depending on the operation conditions of wastewater treatment plants and sampling locations. Poor agreement was found between the predicted (calculation based on the annual consumption and coefficient of sludge water partition) and detected concentrations of the pharmaceuticals indicating that the occurrence of pharmaceutical residues was affected by various factors such as loading rates, sewage properties and the chemical properties such as the contribution from polar groups. National wide fate and ecotoxicity study is required for the development of control strategies.

Evaluation of food chain transfer of the antibiotic oxytetracycline and human risk assessment

There has been recent concern regarding the possibility of antibiotics entering the aquatic food chain and impacting human consumers. This work reports experimental results of the bioconcentration of the antibiotic oxytetracycline (OTC) by the Asian watermeal plant (Wolffia globosa Hartog & Plas) and bioaccumulation of OTC in watermeal and water by the seven-striped carp (Probarbus jullieni). They show, for the first time, the extent to which OTC is able to transfer from water to plant to fish and enter the food chain. The mean bioconcentration factor (dry weight basis) with watermeal was 1.28 × 10(3) L kg(-1). Separate experiments were undertaken to characterize accumulation of OTC by carp from water and watermeal. These showed the latter pathway to be dominant under the conditions employed. The bioconcentration and biomagnification factors for these processes were 1.75 L kg(-1) and 2 × 10(-4) kg g(-1) respectively. Using an aqueous concentration range of 0.34-3.0 μg L(-1), hazard quotients for human consumption of contaminated fish of 1.3 × 10(-2) to 1.15 × 10(-1) were derived.