Illicit drugs have been identified as emerging aquatic pollutants because of their widespread presence in freshwaters and potential toxicity towards aquatic organisms. Among illicit drug residues, cocaine (COC) and its main metabolites, namely benzoylecgonine (BE) and ecgonine methyl ester (EME), are commonly detected in freshwaters worldwide at concentration that can induce diverse adverse effects to non-target organisms. However, the information of toxicity and mechanisms of action (MoA) of these drugs, mainly of COC metabolites, to aquatic species is still fragmentary and inadequate. Thus, this study was aimed at investigating the toxicity of two concentrations (0.3 and 1.0 μg/L) of COC, BE and EME similar to those found in aquatic ecosystems on zebrafish (Danio rerio) embryos at 96 h post fertilization through a functional proteomics approach. Exposure to COC and both its metabolites significantly altered the protein profile of zebrafish embryos, modulating the expression of diverse proteins belonging to different functional classes, including cytoskeleton, eye constituents, lipid transport, lipid and energy metabolism, and stress response. Expression of vitellogenins and crystallins was modulated by COC and both its main metabolites, while only BE and EME altered proteins related to lipid and energy metabolism, as well as to oxidative stress response. Our data confirmed the potential toxicity of low concentrations of COC, BE and EME, and helped to shed light on their MoA on an aquatic vertebrate during early developmental period.

Human presence in the Antarctic is increasing due to research activities and the rise in tourism. These activities contribute a number of potentially hazardous substances. The aim of this study is to conduct the first characterisation of the pharmaceuticals and recreational drugs present in the northern Antarctic Peninsula region, and to assess the potential environmental risk they pose to the environment. The study consisted of a single sampling of ten water samples from different sources, including streams, ponds, glacier drains, and a wastewater discharge into the sea. Twenty-five selected pharmaceuticals and 21 recreational drugs were analysed. The highest concentrations were found for the analgesics acetaminophen (48.74 μg L−1), diclofenac (15.09 μg L−1) and ibuprofen (10.05 μg L−1), and for the stimulant caffeine (71.33 μg L−1). All these substances were detected in waters that were discharged directly into the ocean without any prior purification processes. The hazard quotient (HQ) values for ibuprofen, diclofenac and acetaminophen were far in excess of 10 at several sampling points. The concentrations of each substance measured and used as measured environmental concentration values for the HQ calculations are based on a one-time sampling. The Toxic Unit values indicate that analgesics and anti-inflammatories are the therapeutic group responsible for the highest toxic burden.This study is the first to analyse a wide range of substances and to determine the presence of pharmaceuticals and psychotropic drugs in the Antarctic Peninsula region. We believe it can serve as a starting point to focus attention on the need for continued environmental monitoring of these substances in the water cycle, especially in protected regions such as the Antarctic. This will determine whether pharmaceuticals and recreational drugs are hazardous to the environment and, if so, can be used as the basis for risk-assessment studies to prioritise the exposure to risk.

Fluoroquinolones like difloxacin (DIF) and sarafloxacin (SARA) are adsorbed in soil and enter the aquatic environment wherein they are subjected to photolytic degradation. To evaluate the fate of DIF and SARA, their photolysis was performed in water under stimulated natural sunlight conditions. DIF primarily degrades to SARA. On prolonged photodegradation, seven photoproducts were elucidated by HR-LC-MS/MS, three of which were entirely novel. The residual anti-bacterial activities of DIF, SARA and their photoproducts were studied against a group of pathogenic strains. DIF and SARA revealed potency against both Gram-positive and -negative bacteria. The photoproducts also exhibited varying degrees of efficacies against the tested bacteria. Even without isolating the individual photoproducts, their impact on the aquatic environment could be assessed. Therefore, the present results call for prudence in estimating the fate of these compounds in water and in avoiding emergence of resistance in bacteria caused by the photoproducts of DIF and SARA.

Because of its analgesic properties, acetaminophen (AAP) is widely used to relieve headache. AAP is generally considered safe for humans, but its effects on aquatic organisms are not well known. Here, we have hypothesis that effects of AAP on aquatic organisms would be environmental temperature dependent, because their physiological function depend on the temperature. To test this hypothesis, we used medaka (Oryzias latipes) as a model, because they can live at a wide range of temperatures (0–40 °C). We exposed medaka larvae to 0 (control), 50, or 150 mg/L of AAP at 15, 25 (optimal temperature), or 30 °C for 4 days. Egg yolk absorption was accelerated with raising temperature at any AAP dose. AAP exposure did not have biologically significant effects on survival ratio and body length of larvae at any tested temperature or dose, but heart rate decreased as the dose of AAP and environmental temperature increased. In addition, as the temperature increased, amount of ATP in individual larvae increased in control group, but decreased in AAP exposed group. Subsequently, exposure to 150 mg/L of AAP at 30 °C decreased the number of red blood cells in the gills; we used 150 mg/L of AAP in subsequent hematological and histological analyses. Hematological analysis showed that rising temperature increased the proportion of morphologically abnormal red blood cells in AAP-exposed larvae, suggesting that AAP induced anemia-like signs in larvae. Histological observation of the kidney, which is a hematopoietic organ in fish, revealed no abnormalities. However, in the liver, which is responsible for drug metabolism, the proportion of vacuoles increased with increasing temperature. Although the exposure concentration we tested was higher than environmentally relevant concentrations, our data indicated that rising temperature enhances the toxicity of AAP to medaka larvae, suggesting an ecological risk of AAP due to global warming.

Assessment of the impact of pharmaceutical residues on living organisms is a very complex subject. Apart from taking into account the toxicity of individual compounds, environmental factors should also be taken into account. In this paper, attempts were made to assess the impact of coexisting inorganic ions and changes in pH on the toxicity of ten selected pharmaceuticals. Two bioassays were used to measure the estrogenic and androgenic effects (XenoScreen YES/YAS – Saccharomyces cerevisiae) and acute toxicity (Microtox® – Vibrio fischeri).The Microtox® test gave the most definitive outputs concerning the determination of interaction type between drugs and chemical species. Synergism was proven for almost all drugs and chemical species, and only two cases of antagonism were found. Significant drug/pH interactions were rare.Regarding the XenoScreen YES/YAS bioassay, when estrogenic and androgenic agonistic effects (YES+ and YAS+, respectively) were studied, many cases of well-expressed synergism for all inorganic ions with limited number of drugs (diazepam, fluoxetine, estrone, chloramphenicol for the YES+ test and diazepam, progesterone, androstenedione, and estrone for the YAS+ test) were found. Antagonism was also proven for the YES+ test, especially for diclofenac and androstenedione interacting with cations. On the other hand, the YES- and YAS- tests (estrogenic and androgenic, respectively, antagonistic effects) did not indicate cases of synergetic interaction except for the couples Br−/diazepam and NH4+/ketoprofen. Antagonistic drug/ion interactions were detected only with diclofenac and fluoxetine. It is interesting that well-expressed (antagonism or synergism) drug/pH interactions were rare.Both tests were found utilizable in performing studies on impact of ions/pH fluctuations on drugs mixtures' toxicity confirming in most cases synergic impact of parameters studied on toxicity. The approach proposed in the paper seems to be proven as a reliable tool in assessing impact of abiotic factors on toxicity and endocrine potential of complex mixtures of pharmaceuticals' mixtures.

Anticancer drugs are continuously released into hospital and urban wastewaters, where they, most commonly, undergo conventional treatment in wastewater treatment plants (WWTPs). Wastewaters contain complex mixtures of substances including parent compounds, their metabolites and transformation products (TPs). In this study, samples of hospital effluents and WWTP influents and effluents from Slovenia and Spain were analyzed for twenty-two selected anticancer drugs, their metabolites and transformation products. Acute and chronic toxicity tests were performed on the crustacean Ceriodaphnia dubia, genotoxicity was determined with Tradescantia and Allium cepa micronucleus (MN) assays and in vitro comet assay in zebrafish (Danio rerio) liver cell line (ZFL cells). Sixty of the two hundred-twenty determinations revealed detectable levels of anticancer drug residues. Among the targeted compounds, platinum based were most frequently detected (90%). Furthermore, erlotinib was detected in 80%, cyclophosphamide and tamoxifen in 70% and methotrexate in 60% of the samples. Seven of ten samples were toxic to C. dubia after acute exposure, whereas after chronic exposure all samples reduced reproduction of C. dubia at high sample dilutions. Allium cepa proved insensitive to the potential genotoxicity of the tested samples, while in Tradescantia increased MN frequencies were induced by a hospital effluent and WWTP influents. In ZFL comet assay all but one sample induced a significant increase of DNA strand breaks. Correlations of chemotherapeutics or their TPs were detected for all bioassays except for Allium cepa genotoxicity test, however for each test the highest correlations were found for different substances indicating differential sensitivities of the test organisms.

Stabled livestock reared in housed conditions are often subjected to intensive treatments with veterinary drug, which residues may be present in livestock meat ingested by scavengers, but nothing is known about their presence in eggs of wild birds and their potential detrimental effects on breeding success. We searched for residues of veterinary drugs and other toxicants in infertile and embryonated unhatched eggs of griffon vultures (Gyps fulvus) and red kites (Milvus milvus), two threatened avian scavengers. Quinolones (ciprofloxacin and enrofloxacin) were found in most unhatched eggs of both scavenger species clearly associated with severe alterations in the development of embryo cartilage and bones that could preclude embryo movements and subsequently normal development, pre-hatch position and successful hatching. The detrimental effects on developing eggs of veterinary drugs from livestock operations may help to explain reduced breeding success of avian scavengers. Fluoroquinolones used in livestock farming and found in eggs of avian scavenger caused severe alterations in embryo cartilage and bone development.

Benzotriazole (BT) and 5-methyl-1H-benzotriazole (5-MeBT) are broadly used in industrial applications, such as anti-icing fluids and dishwashing detergent, and act as the primary building blocks for UV absorbers and photostabilizers. This study examined the occurrence of these two compounds in the environment and their unique photochemical behavior affecting photosensitizers and other micro-organic pollutants in aqueous environments. BT and 5-MeBT were detected in all river water samples from the major rivers in Taipei City in the concentration ranges of 147 to 1560 ng/L and 22 to 235 ng/L, respectively, and both compounds persisted through a conventional wastewater treatment plant. The direct photolysis half-lives of BT and 5-MeBT were 56.9 and 14.0 h, respectively. The half-life of photolysis in river water for BT was 44.2 h, whereas the half-life of 5-MeBT was 24.7 h. The long half-lives in real-water matrices resulted in their prevalence in water bodies, and these compounds were also found to minimize the photosensitizing ability of nitrate and dissolved organic matter (DOM) and increase the persistence of other micro-organic pollutant. With BT present, the production of ·OH in nitrate photolysis was reduced, the degradation of DOM under sunlight was hindered, and the photodegradation of pharmaceutical residues in surface water, such as methotrexate, was completely impeded. This study suggests that in cases in which BT and 5-MeBT are highly concentrated, the effectiveness of natural attenuation process, i.e., photodegradation, in the aqueous environment is diminished, which increases the persistence of the pollutants as well as the risk of exposure.

This paper explores the proposition that we are living in an era marked by unprecedented quantities and exotic types of human waste and environmental contamination by examining the impact of anthropogenic activity on the Earth’s epiderm. Specifically, the paper introduces anthrosols and technosols as critical markers of unfettered human activity as recorded in the terrestrial stratigraphic signature of soils and sediments adversely impacted by municipal, agricultural, industrial and maritime activities. The paper presents examples of the sources and fates of some of the most worrisome contaminants, many of them persistent organic pollutants, including common heavy metals-metalloids and hydrocarbons but also instances of more unfamiliar drug residues and antibiotic resistant genes, at Australia’s 160,000 contaminated sites.Consideration is given to how anthropogenic elements and compounds in soil may bioaccumulate and bioconcentrate in animals, and how they can subsequently be consumed to the detriment of human health. Among the 75,000 identified contaminants in Australian soils are tributyltin, which has a half-life of at least 10 years and is one of the most toxic chemicals introduced into the environment by man, and uranium-contaminated mine tailings, which require constant and careful management for up to 75,000 years if their polluting effects are to be minimized. The author concludes that anthrosols and technosols provide evidence of the Anthropocene in Australia.

Degradation and fate of sulfamethazine (SMZ) were determined under aerobic and anaerobic conditions in soil with and without swine manure amendment. For both aerobic and anaerobic conditions, SMZ disappeared rapidly during the first 7 days followed by slow disappearance which may indicate that SMZ had become more persistent and less available. For soils receiving 100 mg/kg of SMZ, the percent of SMZ remaining in the soil after 63 days were between 25 and 60 %. Depending on the initial SMZ concentration, estimated half-lives for aerobic and anaerobic incubations ranged from 1.2 to 6.6 and 2.3 days to more than 63 days, respectively. Addition of manure (0.054 g/g soil) did not significantly affect the half-lives of SMZ. Inhibitory effects of SMZ on anaerobic microbial respiration were observed in unamended soil at concentrations of 50 mg/kg or higher, but only transient inhibitory effects were found in aerobic soil. Five to 22 % of the¹⁴C[phenyl]-SMZ added were extracted at the end of the incubations while 70 to 91 % of the¹⁴C were converted to bound (non-extractable) forms in both manure amended and unamended soil. Only 0.1 to 1.5 % of¹⁴C-SMZ was mineralized to¹⁴CO₂. Disappearance of SMZ in sterilized soil was not completely halted indicating possible contribution of abiotic processes to the disappearance of SMZ in soil.