Sources, impacts and trends of pharmaceuticals in the marine and coastal environment

Mytilidae as model organisms in the marine ecotoxicology of pharmaceuticals - A review

Growing production and consumption of pharmaceuticals is a global problem. Due to insufficient data on the concentration and distribution of pharmaceuticals in the marine environment, there are no appropriate legal regulations concerning their emission. In order to understand all aspects of the fate of pharmaceuticals in the marine environment and their effect on marine biota, it is necessary to find the most appropriate model organism for this purpose. This paper presents an overview of the ecotoxicological studies of pharmaceuticals, regarding the assessment of Mytilidae as suitable organisms for biomonitoring programs and toxicity tests. The use of mussels in the monitoring of pharmaceuticals allows the observation of changes in the concentration and distribution of these compounds. This in turn gives valuable information on the amount of pharmaceutical pollutants released into the environment in different areas. In this context, information necessary for the assessment of risks related to pharmaceuticals in the marine environment are provided based on what effective management procedures can be developed. However, the accumulation capacity of individual Mytilidae species, the bioavailability of pharmaceuticals and their biological effects should be further scrutinized.

Cytotoxic comparison of macrolide antibiotics and their chlorinated disinfection byproduct mixtures

Erythromycin (ERY), azithromycin (AZI) and telithromycin (TEL) are widely-used macrolide antibiotics that are frequently detected in various water environments, including resource water and drinking water. In the performed chlorination disinfection process, at least 10, 20 and 200 new disinfection byproducts of ERY, AZI and TEL, respectively, were observed (the mixtures of the disinfection byproducts of ERY, AZI and TEL were named ERY-M, AZI-M and TEL-M, respectively). There is limited information available regarding their comparative toxicities, and their potential health risks are still unknown. In this study, the Jurkat cell line was used to compare the toxicities of the disinfection byproduct mixtures and their precursor compounds. The cell viability results indicated that the toxicity of ERY-M may not be enhanced after disinfection by chlorination. In contrast, at the same concentrations, AZI-M and TEL-M induced more significant inhibitory effects on cell viability than their parent compounds. Additionally, the total antioxidant capacity (T-AOC) and cell cytokine release (including interleukin-2, interleukin-8 and tumor necrosis factor-α) analyses of AZI-M and TEL-M further verified these results. Our findings demonstrate that the cytotoxicity of AZI and TEL was enhanced during the chlorination disinfection process. This investigation will provide substantial new details related to the toxicity of the mixed disinfection byproducts (DBPs) of ERY, AZI and TEL generated in the chlorination disinfection process.

A baseline assessment of emerging organic contaminants in New Zealand groundwater

Emerging organic contaminants (EOCs) are manufactured compounds, used for a range of purposes, that are a rising concern for freshwater quality, human and aquatic health. Their occurrence in groundwater has been demonstrated in several international surveys. We conducted the first baseline survey on EOC occurrence in New Zealand groundwater, using a wide-screening approach (723 compounds) and a novel stratified to mean residence time (MRT) randomised design to inform future monitoring. A total of 61 sites were sampled: 51 baseline sites from the State of the Environment (SOE) network in the Waikato region and 10 targeted sites located in the vicinity of known EOC sources for comparison. EOCs were detected at 91% of the baseline sites at concentrations ranging from 0.1 to 11,000 ng·L^-1. Multiple groups of EOCs were encountered: pesticides (48 compounds), pharmaceuticals (11), industrial (10), preservatives/food additives (3) and personal care products (1). Similar diversity and concentration range of EOCs were observed at the targeted sites, with the addition of drugs of abuse and life-style compounds. EOC detections occurred across young (1-11 yrs. MRT), intermediate (11-50 yrs. MRT) and old (50-250 yrs. MRT) groundwaters with higher concentrations and more types of EOCs detected at sites in the youngest age category. Concentrations of the 73 compounds detected at baseline sites were comparable to those found in overseas groundwaters with 28 compounds measured at concentrations greater than the EU maximum admissible concentration for pesticides. We used the survey results to: review current pesticide monitoring; propose complementary monitoring; identify potential EOC groundwater tracers and identify compounds for which cost-effective national laboratory capability is needed. The Waikato survey results demonstrated ubiquitous occurrence of unmonitored, unregulated EOCs in groundwater and limitations in using targeted approaches to establish monitoring.

Psychoactive substances in mussels: Analysis and occurrence assessment

This work presents an analytical methodology based on a "Quick, easy, cheap, effective, rugged, and safe" (QuEChERS) extraction and liquid chromatography-tandem mass spectrometry detection (LC-MS/MS) for the simultaneous determination of 35 psychoactive substances in fresh mussel samples. The compounds investigated include illicit drugs, new psychoactive substances, commonly prescribed psychiatric pharmaceuticals, and caffeine. The methodology was validated in terms of recovery (relative recoveries 77-118%), repeatability (relative standard deviation values <20%), and sensitivity (limits of detection and quantification <2 ng/g fresh weight (f.w.) and <6.7 ng/g f.w., respectively, for most compounds). The method was applied to the analysis of 15 samples, covering both commercially available mussels purchased from local food markets and wild fresh mussels collected in the Northeast coast of Spain in the Mediterranean Sea. Only one sample corresponding to wild mussels was found to contain 2 of the target analytes, namely, sertraline (1.5 ng/g f.w.) and caffeine, (12.8 ng/g f.w.).

Occurrences, levels and risk assessment studies of emerging pollutants (pharmaceuticals, perfluoroalkyl and endocrine disrupting compounds) in fish samples from Kalk Bay harbour, South Africa

A comprehensive analysis of 15 target chemical compounds (pharmaceuticals and personal care product, perfluoroalkyl compounds and industrial chemicals) were carried out to determine their concentrations in selected commercially exploited, wild caught small and medium sized pelagic fish species and their organs (Thyrsites atun (snoek), Sarda orientalis (bonito), Pachymetopon blochii (panga) and Pterogymnus laniarius (hottentot)) obtained from Kalk Bay harbour, Cape Town. Solid phase extraction (SPE) method based on Oasis HLB cartridges were used to concentrate and clean-up the samples. Liquid chromatography-mass spectrometry analysis of these chemical compounds revealed the simultaneous presence of at least 12 compounds in different parts of the selected fish species in nanogram-per-gram dry weight (ng/g dw) concentrations. The results revealed that perfluorodecanoic acid, perfluorononanoic acid and perfluoroheptanoic acid were the most predominant among the perfluorinated compounds and ranged between: (20.13-179.2 ng/g), (21.22-114.0 ng/g) and (40.06-138.3 ng/g). Also, diclofenac had the highest concentration in these edible fish species out of all the pharmaceuticals detected (range: 551.8-1812 ng/g). The risk assessment values were above 0.5 and 1.0 for acute and chronic risk respectively which shows that these chemicals have a high health risk to the pelagic fish, aquatic organisms and to humans who consume them. Therefore, there is an urgent need for a precautionary approach and the adequate regulation of the use and disposal of synthetic chemicals that persist in aquatic/marine environment in this province and other parts of South Africa, to prevent impacts on the sustainability of our marine environment, livelihood and lives.

Occurrence and distribution of pharmaceutical compounds in the Danshuei River Estuary and the Northern Taiwan Strait

Ten pharmaceutically active compounds (PhACs) were determined in northern Taiwan estuarine waters and Taiwan Strait (TS) seawater. The ecological risk of these PhACs was assessed using risk quotient (RQ), which is the ratio of the measured maximum concentration to the predicted no-effect concentration. Six PhACs were detected within the estuarine waters. Caffeine concentration (130-718 ng l^-1) was the highest among the analyzed PhACs. The distribution of PhACs in the Danshuei River Estuary generally exhibited addition behavior, except that caffeine showed conservative behavior. Carbamazepine, gemfibrozil, caffeine, and ketoprofen were detected in TS seawaters. Their concentrations follow the sequence: gemfibrozil > ketoprofen > caffeine > carbamazepine. The caffeine concentrations in TS seawaters were 2-3 orders of magnitude lower than those in Danshuei estuarine waters. With few exceptions for caffeine, erythromycin, and sulfadiazine posing low risk in some estuarine waters, most of the RQ values were <0.01, suggesting no adverse effects on aquatic organisms.

Biochemical and physiological responses induced in Mytilus galloprovincialis after a chronic exposure to salicylic acid

A vast variety of substances currently reaches the aquatic environment, including newly developed chemicals and products. Lack of appropriate analytical methods for trace determinations in aquatic ecosystem compartments and lack of information regarding their toxicity explains existing regulation gaps. However, suspicion of their toxicity assigned them as Contaminants of Emerging Concern (CECs). Among CECs are Pharmaceuticals including Salicylic Acid (SA), which is the active metabolite of acetylsalicylic acid (ASA; aspirin). The aim of the present study was to evaluate the potential effects of SA on the mussel Mytilus galloprovincialis. For this, organisms were exposed for 28 days to different concentrations of SA (0.005; 0.05; 0.5 and 5 mg/L), resembling low to highly polluted sites, after which different physiological and biochemical parameters were evaluated to assess organism's respiration rate, neurotoxic, metabolic and oxidative stress status. Our results clearly showed that SA strongly reduced the respiration capacity of mussels. Also, SA inhibited the activity of superoxide dismutase (SOD) and catalase (CAT) enzymes, but increased the activity of glutathione peroxidase (GPx) and glutathione-S-transferases (GSTs), which prevented the occurrence of lipid peroxidation (LPO). Nevertheless, oxidative stress was confirmed by the strong decrease of the ratio between reduce glutathione (GSH) and oxidized (GSSG) glutathione in contaminated mussels. Moreover, neurotoxicity was observed in mussels exposed to SA. Overall, this study demonstrates the metabolic, neurotoxic and oxidative stress impacts of SA in M. galloprovincialis, which may result in negative consequences at the population level.

Sulfate radicals mediated oxidation of amoxicillin: Optimization of key parameters

The lack of selectivity of hydroxyl radical species used in Advanced Oxidation Processes (AOPs) to eliminate organic pollutants has swayed the investigation towards more selective oxidizing agents. In the current work, we investigated the oxidation of amoxicillin, the most commonly used antibiotic worldwide, by sulfate radical species generated from the activation of Persulfate (PS) and Peroxymonosulfate (PMS-Oxone^®). The optimization of this oxidation using the box-behnken experimental design was conducted. From this study, it was shown that the PS/Fe²⁺ mixture was capable of dose-dependently inducing a significant amount of degradation of the Amoxicillin compound with a higher degradation rate detected with higher amounts of PS and Fe²⁺. Sulfate radicals generated from the "Oxidant-Catalyst" mixture were shown to be the predominant oxidizing species involved in this process with the second order rate constant of Amoxicillin degradation found to be equal to 2.79 × 10⁹ M^-1. S^-1. In the optimization procedure, the box-benhken methodology allowed us to assess the impact of various factors and their interaction on COD removal efficiency (mineralization rate), which is the objective response needed to be optimized. The variables considered were PS as the oxidant, Fe²⁺ as the catalyst, and pH. It was concluded that among the various parameters tested, pH was the most influential as a decrease in pH values was shown to be positively correlated with a significant increase in COD removal rate. Hence, the highest mineralization rate of Amoxicillin (≈76.10% COD removal) was achieved with PS = 300 μM, Fe²⁺ = 250 μM, and a pH value of 3.

Removal of emerging drugs of addiction by wastewater treatment and water recycling processes and impacts on effluent-associated environmental risk

Drugs of addiction, have been recognized as potential contaminants of concern to the environment. Effluent wastewater discharge is a major source of contamination to aquatic receiving environments. A year-long monitoring program was undertaken in Australia to characterise the fate of four emerging drugs of addiction: methamphetamine; MDMA; pharmaceutical opioids: codeine and morphine and a metabolite: benzoylecgonine in four wastewater treatment plants operating with different secondary treatment technologies: conventional activated sludge (CAS), membrane bioreactors (MBR), integrated fixed-film AS (IFAS) and sequencing batch reactor (SBR). The effect of subsequent tertiary treatment (coagulation/flocculation) on the removal efficiency was also assessed. Drugs were detected in influent and effluent samples (mean concentration ranged from 43-4777 and 17-1721 ng/L, respectively). Treated effluents had noticeably lower levels compared to raw influents. Removal efficiency of compounds depended on the secondary treatment employed, with IFAS and MBR performing the best with significant removal of compounds (≈90%) followed by CAS (54-96%) and lastly SBR (42-83%). Despite the low levels of drugs measured after the secondary treatment, near complete removal after tertiary treatment (≈99%) was recorded, which demonstrated the effectiveness of using the coagulation/flocculation process as an effective step for enhancing the removal efficiency. The levels of drugs were at a low level in the effluents released into the environment and used for recycling and all posed a low environmental risk in urban water courses based on the risk assessment. The information given here provides new and useful information to the water industry and regulators on the efficiency of drug removal in a range of wastewater treatment configurations.

Presence and environmental risk assessment of selected antibiotics in coastal water adjacent to mariculture areas in the Bohai Sea

The presence and concentrations of 25 antibiotics in Dalian coastal water of the Bohai Sea were investigated using solid-phase extraction coupled with high-performance liquid chromatography tandem mass spectrometry. Results showed that antibiotics were widely detected in this region with total concentration ranging from 22.6 to 2402.4 ng/L. Enrofloxacin and trimethoprim were 100% detected followed by sulfamethoxazole with a detection rate of 90.9%. No significant correlations were found between antibiotics concentrations and sample parameters such as dissolved organic carbon, salinity, and distance from the coast, suggesting that concentrations and distributions of the antibiotics in this area were source-dependent. Antibiotic concentration in the sample from an offshore cage-culture area was the highest. Based on composition profiles, mariculture was supposed to be an important source of antibiotics. According to the assessment, individual antibiotic posed low to moderate risk, while the antibiotic mixture presented high risk. Enrofloxacin, clarithromycin and sulfamethoxazole, the top three contributors to the mixture risk quotients for each site, need priority control in this area. Besides, levels of enrofloxacin were high enough to exert a selective pressure on bacteria that may lead to an increase in the prevalence of resistance.

First indication of deleterious impacts in white-seabream larvae (Diplodus sargus) survival and behaviour following acute venlafaxine exposure

Wastewater effluents are teeming with organisms, nutrients and chemical substances which water treatment processes fail to remove. Among these substances, pharmaceuticals such as antidepressants are a frequent occurrence, and have been reported to lead to severe effects in the physiology and behaviour of non-target marine species across taxa. Venlafaxine (VFX) is one of the most consistently prescribed substances for the treatment of human depressive disorders, acting as a serotonin and norepinephrine reuptake inhibitor. In the present study, the potential effects of this antidepressant on the survival and key behaviours (i.e. movement, aggression and foraging) of white seabream (Diplodus sargus) larvae were addressed. Larvae were submitted to an acute exposure of two different VFX treatments (low concentration, 10 µg L^-1; and high concentration, 100 µg L^-1) for a total of 48 h. Sampling took place after 24 and 48 h of exposure. Overall, results showed a significant effect of a two-day exposure to VFX in larvae of D. sargus. Survival was significantly reduced by exposure to a high concentration, but behavioural effects of antidepressant exposure were subtle: i.e. increased attack frequency and temporary modulation of capture success. Further research efforts should be directed towards evaluating the potential chronic effects of antidepressants in marine species, if we are to anticipate possible pressures on natural populations, and effectively advice policymakers towards the investment in new and more efficient methods of wastewater treatments.

Does salinity modulates the response of Mytilus galloprovincialis exposed to triclosan and diclofenac?

In the present study Mytilus galloprovincialis mussels were exposed for 28 days to three salinities: 30 (control), 25 and 35. Simultaneously, organisms at each salinity were exposed to either the antimicrobial agent Triclosan (TCS) or the pharmaceutical drug Diclofenac (DIC) at 1 μg/L. Salinity alone and exposure to PPCPs changed mussel's metabolic capacity and oxidative status, but no additive or synergetic effects resulting from the combined exposures were observed. Overall, the metabolic capacity of mussels was decreased when exposed to TCS and DIC under control salinity, which was less pronounced at salinities out of the control level. TCS had a notorious effect over glutathione peroxidase activity while DIC exposure enhanced catalase response. Such defence mechanisms were able to prevent cellular damage but still a clear reduction in GSH/GSSG ratio after PPCPs exposures indicates oxidative stress which could compromise bivalve's performance to further stressing events.

Influence of salinity and pH on bioconcentration of ionizable pharmaceuticals by the gulf killifish, Fundulus grandis

Estuaries routinely receive discharges of contaminants of emerging concern from urban regions. Within these dynamic estuarine systems, salinity and pH can vary across spatial and temporal scales. Our previous research identified bioaccumulation of the calcium channel blocker diltiazem and the antihistamine diphenhydramine in several species of fish residing in multiple urban estuaries along the Gulf of Mexico in Texas, where field-measured observations of diltiazem in fish plasma exceeded human therapeutic plasma doses. However, there remains a limited understanding of pharmaceutical bioaccumulation in estuarine environments. Here, we examined the influence of pH and salinity on bioconcentration of three pharmaceuticals in the Gulf killifish, Fundulus grandis. F. grandis were exposed to low levels of the ionizable pharmaceuticals carbamazepine, diltiazem, and diphenhydramine at two salinities (5 ppt, 20 ppt) and two pH levels (6.7, 8.3). pH influenced bioconcentration of select weak base pharmaceuticals, while salinity did not, suggesting that intestinal uptake via drinking does not appear to be a major exposure route of these pharmaceuticals in killifish. Compared to our previous pH dependent uptake observations with diphenhydramine in the fathead minnow model, killifish apparent volume of distribution values were markedly lower than fatheads, though killifish bioconcentration factors were similar at high pH and four fold higher at low pH than freshwater fish. Advancing an understanding of environmental gradient influences on pharmacokinetics among fish is necessary to improve bioaccumulation assessments and interpretation of toxicological observations for ionizable contaminants.

A Review on Biological Processes for Pharmaceuticals Wastes Abatement-A Growing Threat to Modern Society

Over the last decades, the production and consumption of pharmaceuticals and health care products grew manifold, allowing an increase in life expectancy and a better life quality for humans and animals, in general. However, the growth in pharmaceuticals production and consumption comes with an increase in waste production, which creates a number of challenges as well as opportunities for the waste management industries. The conventional current technologies used to treat effluents have shown to be inefficient to remove or just to reduce the concentrations of these types of pollutants to the legal limits. The present review provides a thorough state-of-the-art overview on the use of biological processes in the rehabilitation of ecosystems contaminated with the pharmaceutical compounds most commonly detected in the environment and eventually more studied by the scientific community. Among the different biological processes, special attention is given to biosorption and biodegradation.

Polystyrene nanoplastics alter the cytotoxicity of human pharmaceuticals on marine fish cell lines

There is an increasing concern on the consequences of the presence of micro(nano)plastics to marine organisms. The present study aimed to provide information on the effects of polystyrene nanoplastics (PSNPs) to fish cells alone and combined with human pharmaceuticals, other emerging contaminants, using as biological models marine fish cell lines SAF-1 and DLB-1. Cells were exposed for 24 h to 100 nm PSNPs, starting at 0.001 up to 10 mg/L, to assess effects on viability and activity of catalase (antioxidant defense) and glutathione S-transferases (phase II biotransformation and antioxidant defense). The viability of cells was also evaluated after exposure to human pharmaceuticals alone and combined with PSNPs. Overall, PSNPs failed to be cytotoxic but data proved their ability to alter the toxicity of human pharmaceuticals. DLB-1 was the most sensitive cell line to PSNPs. Data support the use of marine fish cell lines in the study of the effects of micro(nano)plastics.

Psychoactive pharmaceuticals and illicit drugs in coastal waters of North-Western Spain: Environmental exposure and risk assessment

The knowledge on the presence of pharmaceutical compounds, and possible risks, in coastal and marine systems is still limited. This study represents the first attempt at monitoring psychoactive pharmaceuticals (PaPs) (benzodiazepines and anxiolytics) and illicit drugs (IDs) in the Rías Baixas coastal area of Northwestern Spain, an area of economic and ecological relevance, leader in shellfish production. Fourteen PaPs and 9 IDs were detected in the water samples with venlafaxine (59%), benzoylecgonine (40%), EDDP (40%), and citalopram (36%) showing the highest detection frequencies. The highest concentrations were measured for venlafaxine (291 ng L^-1), benzoylecgonine (142 ng L^-1), lorazepam (95.9 ng L^-1), and citalopram (92.5 ng L^-1). Risk assessment, based on hazard quotients suggested that venlafaxine, citalopram, sertraline, and EDDP were present in concentrations potentially able to cause chronic effects in exposed organisms. Based on the results obtained further monitoring of venlafaxine, citalopram, and EDDP in coastal waters is recommended.

Corbicula fluminea rapidly accumulate pharmaceuticals from an effluent dependent urban stream

Freshwater bivalve populations are stressed by watershed development at the global scale. Though pharmaceuticals released from wastewater treatment plant effluent discharges are increasingly reported to bioaccumulate in fish, an understanding of bioaccumulation in bivalves is less defined. In the present study, we examined accumulation of 12 target pharmaceuticals in C. fluminea during a 42 day in situ study in Pecan Creek, an effluent dependent wadeable stream in north central Texas, USA. Caged clams were placed at increasing distances (5 m, 643 m, 1762 m) downstream from a municipal effluent discharge and then subsampled on study days 7, 14, 28 and 42. Acetaminophen, caffeine, carbamazepine, diltiazem, diphenhydramine, fluoxetine, norfluoxetine, sertraline, desmethylsertraline, and methylphenidate were identified in C. fluminea whole body tissue homogenates via isotope dilution liquid chromatography-tandem mass spectrometry. Tissue concentrations ranged from low μg/kg (methylphenidate) to 341 μg/kg (sertraline). By study day 7, rapid and apparent pseudo-steady state accumulation of study compounds was observed in clams; this observation continued throughout the 42 d study. Notably, elevated bioaccumulation factors (L/kg) for sertraline were observed between 3361 and 6845, which highlights the importance of developing predictive bioaccumulation models for ionizable contaminants with bivalves. Future research is also necessary to understand different routes of exposure and elimination kinetics for pharmaceutical accumulation in bivalves.

Occurrence and level of emerging organic contaminant in fish and mollusk from Klang River estuary, Malaysia and assessment on human health risk

The occurrence, level, and distribution of multiclass emerging organic contaminants (EOCs) in fish and mollusks from the Klang River estuary were examined. The targeted EOCs for this assessment were phenolic endocrine disrupting compounds (bisphenol A, 4-OP, and 4-NP), organophosphorous pesticides (quinalphos, chlorpyrifos, and diazinon), estrogenic hormones (E2, E1, and EE2), and pharmaceutically active chemicals (primidone, sulfamethoxazole, dexamethasone, diclofenac, amoxicillin, progesterone, and testosterone). Results from this study showed that the prevalent contamination of the Klang River estuary by EOCs with diclofenac, bisphenol A, progesterone, and amoxicillin were predominantly detected in fish and mollusks. Among the EOCs, diclofenac and progesterone had the highest concentrations in fish and mollusk samples, respectively. The concentrations of diclofenac and progesterone in fish and mollusk samples range from 1.42 ng/g to 10.76 ng/g and from 0.73 ng/g to 9.57 ng/g, respectively. Bisphenol A should also be highlighted because of its significant presence in both fish and mollusks. The concentration of bisphenol A in both matrices range from 0.92 ng/g to 5.79 ng/g. The calculated hazard quotient (HQ) for diclofenac, bisphenol A, and progesterone without consideration to their degradation byproduct were less than one, thus suggesting that the consumption of fish and mollusks from the Klang River estuary will unlikely pose any health risk to consumers on the basis of the current assessment. Nonetheless, this preliminary result is an important finding for pollution studies in Malaysian tropical coastal ecosystems, particularly for organic micropollutant EOCs, and can serve as a baseline database for future reference.

Biomarker and behavioural responses of an estuarine fish following acute exposure to fluoxetine

Antidepressants such as fluoxetine are frequently detected in estuaries and can have profound effects on non-target organisms by interfering with the neural system and affecting essential physiological processes and behaviours. In this context, short-term effects of fluoxetine exposure were analysed in the common goby Pomatoschistus microps, an estuarine resident fish species. Two experiments were conducted with fish exposed to: i) fluoxetine concentrations within the μg/L range for 96 h (0.1, 0.5, 10 and 100 μg/L) and ii) fluoxetine concentrations within the mg/L range for 1 h (1, 5 and 10 mg/L). Acute toxicity was assessed via multiple biomarker responses, namely: activity levels of antioxidant (superoxide dismutase and catalase) and detoxification enzymes (ethoxyresorufin O-deethylase and glutathione S-transferase); and biomarkers of effects (lipid peroxidation and DNA damage) and of neurotoxicity (acetylcholinesterase inhibition). Furthermore, behavioural responses concerning activity (active time, movement delay and number of active individuals) and feeding (number of feeding individuals) were also recorded and analysed. Acute fluoxetine exposure for 96 h (in the μg/L range) reduced antioxidant CAT activity with increasing concentrations but had no significant effect on SOD activity. Biotransformation enzymes showed bell-shaped response curves, suggesting efficient fluoxetine metabolism at concentrations up to 10 μg/L. No significant damage (LPO and DNAd) was observed at both concentration ranges (μg/L and mg/L), yet 1 h exposure to higher fluoxetine concentrations (mg/L range) inhibited acetylcholinesterase activity (up to 37%). Fluoxetine (at mg/L) also decreased the number of both feeding and active individuals (by 67%), decreased fish active time (up to 93%) and increased movement delay almost 3-fold (274%). Overall, acutely exposed P. microps were able to cope with fluoxetine toxicity at the μg/L range but higher concentrations (mg/L) affected fish cholinergic system and behavioural responses.

Histopathological effects in gills and liver of Sparus aurata following acute and chronic exposures to erythromycin and oxytetracycline

Due to their worldwide use and environmental persistence, antibiotics are frequently detected in various aquatic compartments. Their toxic properties raise environmental concerns to non-target organisms. Histopathology data is frequently applied in ecotoxicology studies to assess the effects of different classes of environmental stressors in fish, including antibiotics. Tissue alterations in gills and liver of gilthead seabream (Sparus aurata) individuals acutely (96 h) and chronically (28 days) exposed to environmentally relevant concentrations of the antibiotics erythromycin (ERY: 0.0002-200 μg/L) and oxytetracycline (OTC: 0.0004-400 μg/L), including a control non-exposed group, were evaluated. Several disorders (circulatory, regressive, progressive, and inflammatory) were observed in both organs of all exposed animals. The hereby obtained data showed a higher and significant increase in gill histopathological index of organisms acutely exposed to ERY and of those chronically exposed to OTC. In terms of categorical lesions, only a significant increase of regressive and progressive alterations occurred in gills after chronic exposure to OTC. For the liver, a significant increase in pathological index was also detected, as well as regressive changes, after chronic exposure to OTC. Furthermore, the present study indicates that most of the changes observed in gills and liver were of mild to moderate severity, which might be adaptive or protective, non-specific, and mostly reversible. Despite being observed, irreversible lesions were not significant in any of the fish organs analyzed. Although there were histological changes, gill apparatus was considered still functionally normal, as well as liver tissue, not supporting the occurrence of severe toxicity. In general, the observed histological changes were not stressor-specific, and toxicological mechanistic explanations for the alterations observed in gills and liver are presented. The obtained data showed that histopathological biomarkers can be successfully applied in ecotoxicological studies, evidencing their relevance, responsivity, and complementarity to other biochemical biomarker-based approaches.

Assessing the risk of utilizing tidal coastal wetlands for wastewater management

Coastal tidal wetlands are well recognized for the key ecosystem services they provide such as flood protection, water quality improvement, and carbon sequestration. In the southeastern United States, some communities rely on coastal wetlands for the management of secondarily treated effluents in forested and emergent wetlands. Advocates for this practice have argued that wetlands can assimilate nitrogen from wastewater, which can improve cypress-tupelo swamp productivity, and enhance marsh accretion rates to mitigate the effects of sea level rise. In contrast, evolving research on coastal wetlands and the environmental impacts of wastewater treatment pose new questions about the potential risks introduced by this practice. This review seeks to: (1) assess current research on plant productivity in fertilized coastal wetlands; (2) highlight the occurrence and fate of pharmaceuticals and personal care products (PPCPs) in municipal wastewater operations; and (3) identify knowledge gaps. Nutrient additions via wastewater augmented aboveground productivity, but decreased belowground productivity and root-to-shoot ratios. Removal efficiencies of some PPCPs by coastal wetlands have been substantial (75% - 99%), but most remain unevaluated. Furthermore, their fate and effect on local ecosystem function and biogeochemical processes remain in question. This review demonstrates that there is more research needed at both local and watershed scales to evaluate how these risk factors impact ecosystem integrity and to better understand the tradeoffs with this wastewater management practice.

Evaluation of bioconcentration and metabolism of diclofenac in mussels Mytilus trossulus - laboratory study

Interest in the presence of pharmaceutically active compounds in the aquatic environment has been growing for over 20 years, yet very few studies deal with the metabolism of pharmaceuticals in marine organisms. In this study, the bioaccumulation under short-term conditions and metabolism of diclofenac were investigated. Mytilus trossulus was used as a representative of the Baltic benthic fauna. The mussels were exposed to diclofenac at a concentration of 133.33 μg/L for five days, following a five-day depuration phase. The highest concentration of diclofenac (7.79 μg/g dw) in tissues was determined on day 3. Subsequently, the concentration of diclofenac in tissues decreased rapidly to 0.86 μg/g dw on day 5. After five days of depuration, the concentration of diclofenac was 0.21 μg/g dw. Hydroxylated diclofenac metabolites were found both in tissues of mussels and water. This study shows that M. trossulus has the potential to accumulate diclofenac and metabolize it to 4-OH and 5-OH diclofenac.

Genotoxicity of gold nanoparticles in the gilthead seabream (Sparus aurata) after single exposure and combined with the pharmaceutical gemfibrozil

Due to their diverse applications, gold nanoparticles (AuNPs) are expected to increase of in the environment, although few studies are available on their mode of action in aquatic organisms. The genotoxicity of AuNPs, alone or combined with the human pharmaceutical gemfibrozil (GEM), an environmental contaminant frequently detected in aquatic systems, including in marine ecosystems, was examined using gilthead seabream erythrocytes as a model system. Fish were exposed for 96 h to 4, 80 and 1600 μg L^-1 of 40 nm AuNPs with two coatings - citrate or polyvinylpyrrolidone; GEM (150 μg L^-1); and a combination of AuNPs and GEM (80 μg L^-1 AuNPs + 150 μg L^-1 GEM). AuNPs induced DNA damage and increased nuclear abnormalities levels, with coating showing an important role in the toxicity of AuNPs to fish. The combined exposures of AuNPs and GEM produced an antagonistic response, with observed toxic effects in the mixtures being lower than the predicted. The results raise concern about the safety of AuNPs and demonstrate interactions between them and other contaminants.

Evaluation of combined sewer overflow impacts on short-term pharmaceutical and illicit drug occurrence in a heavily urbanised tidal river catchment (London, UK)

The occurrence of pharmaceutical and illicit drug residues potentially arising from combined sewer overflows (CSOs) in the Central London portion of the Thames Estuary is presented. Approximately 39 million tonnes of untreated sewage enter the River Thames at 57 CSO points annually. Differential analysis of influents and effluents in a major wastewater treatment plant identified seven potential drug-related CSO markers based on removal rates. Three were present in influent at concentrations >1 μg L^-1 (caffeine, cocaine and benzoylecgonine). During dry weather, analysis of hourly samples of river water revealed relatively consistent concentrations for most drugs, including CSO markers, over a tidal cycle. River water was monitored over a week in January and July and then daily across six consecutive weeks in November/December 2014. Out of 31 compounds monitored, 27 drug residues were determined in the River Thames and, combined, ranged between ~1000-3500 ng L^-1. Total drug concentration generally declined during extended periods of drier weather. For CSO markers, short-term increases in caffeine, cocaine and benzoylecgonine concentration were observed ~24 h after CSO events (especially those occurring at low tide) and generally within one order of magnitude. Timings of elevated occurrence also correlated well with ammonium ion and dissolved oxygen data following CSOs. This work also represents an important study of pharmaceutical occurrence before a major 'Super Sewer' infrastructure upgrade in London aiming to reduce CSOs by 95%.

Behavioural effects of psychoactive pharmaceutical exposure on European perch (Perca fluviatilis) in a multi-stressor environment

With the ability to resist biodegradation and exert therapeutic effects at low concentrations, pharmaceutical contaminants have become environmental stressors for wildlife. One such contaminant is the anxiolytic oxazepam, a psychoactive pharmaceutical that is frequently detected in surface waters globally. Despite growing interest in understanding how wildlife respond to anxiolytics, synergistic effects of pharmaceuticals and other abiotic (e.g. temperature) and biotic (e.g. predation risk) stressors remain unclear. Here, using a multi-stressor approach, we investigated effects of 7-day oxazepam exposure (6.5 μg/L) on anxiety-related behaviours in juvenile European perch (Perca fluviatilis). The multi-stressor approach was achieved by exposing perch to oxazepam at two temperatures (10 °C and 18 °C), and at two predation risk regimes-generated using chemical cues from the northern pike (Esox lucius). Our exposures resulted in a successful uptake of the drug from the water, i.e., oxazepam was measured in perch muscle tissue at 50 ± 17 ng/g (mean ± SD). We found significant oxazepam-induced effects on boldness, with 76.7% of the treated fish entering the white background (i.e. 'exposed' area where exposure to presumed risks are higher) within the first 5 min, compared to 66.6% of the control fish. We also found a significant effect of temperature on total time spent freezing (i.e. staying motionless). Specifically, fish in the low temperature treatments (oxazepam, predation) froze for longer than fish in high temperatures. Our multi-stressor study is the first to uncover how anxiety-related behaviours in wild juvenile fish are altered by changes in water temperature and perceived predation risk. Importantly, our findings highlight the need to focus on multiple stressors to improve understanding of how organisms not only survive, but adapt to, human-induced environmental change.

Mating under the influence: male Siamese fighting fish prefer EE2-exposed females

Countless pharmaceuticals and endocrine disrupting chemicals (EDCs) exist on the market with more added each day. Many of these compounds are not removed during the wastewater treatment process and enter bodies of water in their active form. EDCs are known to have physiological and behavioral effects in exposed organisms. Exposure to the synthetic estrogen 17α-ethinylestradiol (EE2), a common EDC found in birth control pills, has been found to lead to population collapse after only a few generations in some fish species. Mechanisms identified as potential driving forces for collapse include feminization of males and altered fecundity in both sexes. However, an additional way in which EE2 could lead to population collapse is by altering courtship behavior, which could then change mating preferences and decrease mating opportunities. The current study had the following objectives: determine if exposing female Siamese fighting fish, Betta splendens, to EE2 changes mate choice in males; assess if the dose and duration of female exposure matters; and examine if exposing males to EE2 influences their mating preferences. Both unexposed and exposed males were presented with pairs of females that differed in EE2 dose and exposure duration. The results indicate that males were more responsive to EE2-exposed females than unexposed females, with males being most responsive to females exposed to the low versus high dose. Furthermore, exposed males responded less overall than unexposed males. If EE2 concentration increases in the environment, the likelihood of successful mating could decrease and, therefore, potentially lead to adverse population impacts.

Pharmaceuticals as chemical markers of wastewater contamination in the vulnerable area of the Ebro Delta (Spain)

This study evaluated the occurrence and distribution of 81 pharmaceutically active compounds (PhACs) in the vulnerable area of the Ebro Delta region (Catalonia, Spain), to assess the environmental impact of wastewater treatment plants discharge to coastal environments. The occurrence of PhACs was followed along the wastewater-recipient water-sediment chain until they reach estuaries and the Mediterranean Sea. Water and sediment samples were collected in an integrated way at different sampling points covering three different seasons in reaches of the Ebro River located upstream and downstream from wastewater treatment plants (WWTPs), surrounding channels, estuaries, and the associated receiving seawater. 28 out of the 57 compounds detected in effluent wastewater were positively identified in estuary and seawaters, revealing that WWTP discharges are an important source of contamination in coastal environments and that PhACs are suitable markers of urban contamination in these areas. The substances with the highest frequency of detection belonged to the groups of analgesics/anti-inflammatories (acetaminophen, salicylic acid), antihypertensives (valsartan), psychiatric drugs (carbamazepine), and antibiotics (clarithromycin, trimethoprim). In general, a decrease in concentration was observed from inland sampling points towards the Mediterranean Sea, resulting from a dilution in the recipient marine water bodies. A reduced number of PhACs, at concentrations ranging from 0.1 to 12.5 ng g^-1 dry weight (d.w.) was detected in sediment samples, indicating that sorption is a minor natural attenuation pathway for these compounds. Finally, a prioritization strategy, based on the compounds concentration and frequency of detection in seawater, removal efficiency in WWTP, bioaccumulation potential, toxicity to marine organisms and persistency, was used to highlight the PhACs of major ecological concern and that could be used as relevant indicators of wastewater contamination in coastal environments.

Ecotoxicity of the lipid-lowering drug bezafibrate on the bioenergetics and lipid metabolism of the diatom Phaeodactylum tricornutum

Pharmaceutical residues impose a new and emerging threat to the marine environment and its biota. In most countries, ecotoxicity tests are not required for all pharmaceutical residues classes and, even when mandatory, these tests are not performed using marine primary producers such as diatoms. These microalgae are among the most abundant class of primary producers in the marine realm and key players in the marine trophic web. Blood-lipid-lowering agents such as bezafibrate and its derivatives are among the most prescribed drugs and most frequently found human pharmaceuticals in aquatic environments. The present study aims to investigate the bezafibrate ecotoxicity and its effects on primary productivity and lipid metabolism, at environmentally relevant concentrations, using the model diatom Phaeodactylum tricornutum. Under controlled conditions, diatom cultures were exposed to bezafibrate at 0, 3, 6, 30 and 60 μg L^-1, representing concentrations that can be found in the vicinity of discharges of wastewater treatment plants. High bezafibrate concentrations increased cell density and are suggested to promote a shift from autotrophic to mixotrophic metabolism, with diatoms using light energy generated redox potential to breakdown bezafibrate as carbon source. This was supported by an evident increase in cell density coupled with an impairment of the thylakoid electron transport and consequent photosynthetic activity reduction. In agreement, the concentrations of plastidial marker fatty acids showed negative correlations and Canonical Analysis of Principal coordinates of the relative abundances of fatty acid and photochemical data allowed the separation of controls and cells exposed to bezafibrate with high classification efficiency, namely for photochemical traits, suggesting their validity as suitable biomarkers of bezafibrate exposure. Further evaluations of the occurrence of a metabolic shift in diatoms due to exposure to bezafibrate is paramount, as ultimately it may reduce O₂ generation and CO₂ fixation in aquatic ecosystems with ensuing consequences for neighboring heterotrophic organisms.

Spatial and temporal influence of onsite wastewater treatment systems, centralized effluent discharge, and tides on aquatic hazards of nutrients, indicator bacteria, and pharmaceuticals in a coastal bayou

In the rapidly urbanizing watersheds and estuaries flowing to the Gulf of Mexico in Texas, USA, instream flows are increasingly influenced by point source and nonpoint source discharges. Spatial and temporal tidal influences on water quality, especially for contaminants of emerging concern (CECs), is poorly understood in estuaries and coastal systems. We selected Dickinson Bayou, an urban estuary in Galveston County, Texas, for study because it has historically impaired water quality, receives point source discharge from one major wastewater treatment plant (WWTP), while also being influenced by high densities of onsite sewage facilities upstream in the watershed. We explored the occurrence and potential hazards of aquatic contaminants, including nutrients, indicator bacteria for pathogens, and CECs, in relation to this point source discharge, across seasons and at high and low tides. Aquatic contaminants and associated hazards varied significantly in relation to the WWTP discharge, and were influenced by onsite systems. In fact, spatiotemporal water quality varied by class of contaminants (e.g., nutrients, indicator bacteria, CECs), which indicates that traditional surface water monitoring activities should account for such environmental complexity. This study provides a diagnostic approach for future studies of emerging water quality challenges across gradients of rapidly urbanizing coastal bays and estuaries.

Living in a multi-stressors environment: An integrated biomarker approach to assess the ecotoxicological response of meagre (Argyrosomus regius) to venlafaxine, warming and acidification

Pharmaceuticals, such as the antidepressant venlafaxine (VFX), have been frequently detected in coastal waters and marine biota, and there is a growing body of evidence that these pollutants can be toxic to non-target marine biota, even at low concentrations. Alongside, climate change effects (e.g. warming and acidification) can also affect marine species' physiological fitness and, consequently, compromising their ability to cope with the presence of pollutants. Yet, information regarding interactive effects between pollutants and climate change-related stressors is still scarce. Within this context, the present study aims to assess the differential ecotoxicological responses (antioxidant activity, heat shock response, protein degradation, endocrine disruption and neurotoxicity) of juvenile fish (Argyrosomus regius) tissues (muscle, gills, liver and brain) exposed to VFX (via water or feed), as well as to the interactive effects of warming (ΔT °C = +5 °C) and acidification (ΔpCO₂ ~ +1000 µatm, equivalent to ΔpH = -0.4 units), using an integrated multi-biomarker response (IBR) approach. Overall, results showed that VFX toxicity was strongly influenced by the uptake pathway, as well as by warming and acidification. More significant changes (e.g. increases surpassing 100% in lipid peroxidation, LPO, heat shock response protein content, HSP70/HSC70, and total ubiquitin content, Ub,) and higher IBR index values were observed when VFX exposure occurred via water (i.e. average IBR = 19, against 17 in VFX-feed treatment). The co-exposure to climate change-related stressors either enhanced (e.g. glutathione S-transferases activity (GST) in fish muscle was further increased by warming) or attenuated the changes elicited by VFX (e.g. vitellogenin, VTG, liver content increased with VFX feed exposure acting alone, but not when co-exposed with acidification). Yet, increased stress severity was observed when the three stressors acted simultaneously, particularly in fish exposed to VFX via water (i.e. average IBR = 21). Hence, the distinct fish tissues responses elicited by the different scenarios emphasized the relevance of performing multi-stressors ecotoxicological studies, as such approach enables a better estimation of the environmental hazards posed by pollutants in a changing ocean and, consequently, the development of strategies to mitigate them.

Legacy and emerging pollutants in the Gulf of Gdańsk (southern Baltic Sea) - loads and distribution revisited

Coastal marine areas of densely populated countries are exposed to a wide array of human activities having an impact on their ecological status. The Baltic Sea is particularly susceptible to pollution by hazardous substances (limited water exchange, shallowness, and large catchment area). Polish media regularly reports ecological catastrophes in the Gulf of Gdańsk area caused by eg. shipwrecks leaking. Thus, there is a need of a broad scientific based report on recent contaminant loads and distribution. In this review paper, we report loads of contaminants from different obvious and non-obvious sources. We also gather data on legacy and new emerging contaminant concentrations measured in the Gulf of Gdańsk within the last decade (2008-2018). The paper also includes available biological effect measurements performed recently as well as a summary of needs and gaps to be filled for the development of reliable risk assessment.

Occurence and Prioritization of Pharmaceutical Active Compounds in Domestic/Municipal Wastewater Treatment Plants

In this study, pharmaceutically active compounds (PhACs) were analyzed in the influent and effluent of a domestic wastewater treatment plant in Turkey and a municipal wastewater treatment plant in Germany and the toxicity of these wastewaters were estimated using a toxic unit (TU) approach. A total of 21 and 32 PhACs were detected in the domestic wastewater and the municipal wastewater, respectively. The TUs estimated for PhACs in municipal wastewater were higher than the TUs estimated for PhACs present in domestic wastewater. The levels of the anti-anxiety drug, oxazepam were estimated to be in the high risk category (HQ > 10) in both wastewaters. In bench-scale tests with ozonation, the removals of four PhACs in the municipal wastewater were investigated. At a dose of 2 mg/L ozone, 97%-98% of diclofenac and carbamazepine were removed. The lowest removal rate at 71% was observed for metoprolol.

Bioaccumulation and ecotoxicological responses of juvenile white seabream (Diplodus sargus) exposed to triclosan, warming and acidification

Triclosan (TCS) is a synthetic microbial compound widely used in the formulation of various personal care products. Its frequent detection in marine ecosystems, along with its physical and chemical properties, suggest that TCS can be highly persistent, being easily bioaccumulated by biota and, therefore, eliciting various toxicological responses. Yet, TCS's mechanisms of bioaccumulation and toxicity still deserve further research, particularly focusing on the interactive effects with climate change-related stressors (e.g. warming and acidification), as both TCS chemical behaviour and marine species metabolism/physiology can be strongly influenced by the surrounding abiotic conditions. Hence, the aim of this study was to assess TCS bioaccumulation and ecotoxicological effects (i.e. animal fitness indexes, antioxidant activity, protein chaperoning and degradation, neurotoxicity and endocrine disruption) in three tissues (i.e. brain, liver and muscle) of juvenile Diplodus sargus exposed to the interactive effects of TCS dietary exposure (15.9 μg kg^-1 dw), seawater warming (ΔTºC = +5 °C) and acidification (ΔpCO₂ ∼ +1000 μatm, equivalent to ΔpH = -0.4 units). Muscle was the primary organ of TCS bioaccumulation, and climate change stressors, particularly warming, significantly reduced TCS bioaccumulation in all fish tissues. Furthermore, the negative ecotoxicological responses elicited by TCS were significantly altered by the co-exposure to acidification and/or warming, through either the enhancement (e.g. vitellogenin content) or counteraction/inhibition (e.g. heat shock proteins HSP70/HSC70 content) of molecular biomarker responses, with the combination of TCS plus acidification resulting in more severe alterations. Thus, the distinct patterns of TCS tissue bioaccumulation and ecotoxicological responses induced by the different scenarios emphasized the need to further understand the interactive effects between pollutants and abiotic conditions, as such knowledge enables a better estimation and mitigation of the toxicological impacts of climate change in marine ecosystems.

Comparison of Prioritisation Schemes for Human Pharmaceuticals in the Aquatic Environment

Only a small proportion of pharmaceuticals available for commercial use have been monitored in the aquatic environment, and even less is known about the effects on organisms. With thousands of pharmaceuticals in use, it is not feasible to monitor or assess the effects of all of these compounds. Prioritisation schemes allow the ranking of pharmaceuticals based on their potential as environmental contaminants, allowing resources to be appropriately used on those which are most likely to enter the environment and cause greatest harm. Many different types of prioritisation schemes exist in the literature and those utilising predicted environmental concentrations (PECs), the fish plasma model (FPM), critical environmental concentrations (CECs) and acute ecotoxicological data were assessed in the current study using the 50 most prescribed drugs in the UK. PECs were found to be overestimates of mean measured environmental concentrations but mainly underestimations of maximum concentrations. Acute ecological data identified different compounds of concern to the other effects assessments although the FPM and CECs methods were more conservative. These schemes highlighted antidepressants, lipid regulators, antibiotics, antihypertensive compounds and ibuprofen as priority compounds for further study and regulation.

Assessment of toxic effects of the antibiotic erythromycin on the marine fish gilthead seabream (Sparus aurata L.) by a multi-biomarker approach

Erythromycin (ERY) is one of the most common antibiotics used in human and veterinary practices, leading to ubiquitous environmental distribution and possible toxicity to non-target organisms. The purpose of this study was to determine sub-lethal effects of ERY towards the marine fish Sparus aurata (gilthead seabream). S. aurata were acutely (0.3-323 μg/L, 96 h) and chronically (0.7-8.8 μg/L, 28 d) exposed to ERY. Detoxification [7-ethoxyresorufin O-deethylase (EROD), glutathione S-transferases (GSTs), uridine-diphosphate-glucuronosyltransferase (UGT)], oxidative stress [catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GRed)], lipid peroxidation [thiobarbituric acid reactive substances - (TBARS)], genotoxicity [genetic damage index (GDI) and erythrocytic nuclear abnormalities (ENAs)], neurotransmission [acetylcholinesterase (AChE)] and energy metabolism [lactate dehydrogenase (LDH)] biomarkers were evaluated. Results showed that ERY did not promote significant effects in detoxification biomarkers, but induced slight pro-oxidative effects (decrease of GPx activity in the liver after acute exposure and an increase in gills after chronic exposure; and an increase of hepatic GRed activity following chronic exposure). There was a significant decrease in TBARS after chronic exposure, which contradicts a full scenario of oxidative stress. In terms of genotoxicity, both ERY exposures caused only a significant increase of GDI. Neurotransmission and energy metabolism were not also affected by ERY. Although few toxic effects of ERY have been previously documented (involving different metabolic pathways, as tested in this work), these were mainly observed for freshwater species. These findings suggest low vulnerability of S. aurata to ERY at levels close to the ones found in the wild.

Doramectin induced cytotoxic and genotoxic effects on bovine peripheral lymphocytes and cumulus cells in vitro

The effect of doramectin (DOR) was tested on two experimental somatic bovine cells in vitro: peripheral lymphocytes (PL) and cumulus cells (CC). The cytotoxicity and genotoxicity of DOR were assessed using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, single cell gel electrophoresis assay (SCGE) and cytokinesis-block micronucleus cytome (CBMN Cyt) assay. Both cells were treated with three concentrations of DOR (20, 40, 60 ng mL^-1) for 24 h. The results obtained from PL demonstrated that DOR was able to induce cytotoxic effect and DNA damage with all concentrations tested. Additionally, DOR increased micronuclei (MNi) frequency and nuclear buds (NBuds) with 20, 40, 60 ng mL^-1, and nucleoplasmic bridges (NPBs) only with 40 ng mL^-1. On the other hand, the three concentrations of DOR were not able to induce cytotoxic effect and DNA damage using SCGE in the bovine CC. Nevertheless, the two higher concentrations of DOR (20, 40 µg mL^-1) significantly increased the frequency of micronucleus formation in bovine CC. These results represent the first experimental evidence of genotoxic and cytotoxic effects exerted by DOR on bovine PL and CC.

Genotoxicity of selected pharmaceuticals, their binary mixtures, and varying environmental conditions - study with human adenocarcinoma cancer HT29 cell line

Pharmaceutical residues are present in the environment in mixtures and their adverse effects may also result from interactions that occur between compounds. Studies presented in this work focus on genotoxicity of pharmaceuticals from different therapeutic groups in mixtures and in individual solutions impacted with different environmental conditions assessed using comet assay (alkaline approach). Binary mixtures of pharmaceuticals (in different concentration ratios) and in individual solutions impacted with pH change (range from 5.5 to 8.5) or addition of inorganic ions, were incubated with HT29 cells and after 24 h time period cells were tested for the presence of DNA damage. To estimate whether mixtures act more (synergistic) or less (antagonistic) efficiently Concentrations Addition (CA) and Independent Action (IA) approaches were applied followed by a calculation of the Model Deviation Ratio (MDR) to determine deviation from the predicted values. Addition of inorganic ions mainly reduced their genotoxicity. Diclofenac s. was the most susceptible to potassium, fluoride, and bromide ions. Change of the pH of pharmaceutical solutions had significant impact on genotoxicity of diclofenac s. and fluoxetine h. Among mixtures, more commonly observed interactions were synergistic ones, exactly twenty-five cases (ten pairs containing chloramphenicol or oxytetracycline h.) and ten cases of antagonism (four for pairs containing chloramphenicol or fluoxetine h.). The results obtained indicate that interactions between tested compounds occur frequently and can lead to DNA damage. This topic especially concerning in vitro tests using cells is still rare, however, it should not be neglected.

Wastewater Reflections in Consumer Mind: Evidence from Sewage Services Consumer Behaviour

Environmental concerns have become an important decision-making determinant for consumers. Hundreds of emerging pollutants and their metabolites are listed as present in European aquatic environments and human settlements are blamed as major sources of water pollution. It was assumed that as long as water treatment is not totally effective and it requires a high amount of energy and resources, household’s contribution through correct behaviour in relation to the load of waste they discharge in the sewage system can reduce efforts towards wastewater treatment. Consequently, the main objective of this study was to investigate households’ perception and behaviour related to wastewater treatment services. Results are based on a random survey with a sample of 125 Romanian consumers of water supply and sewage services. A key finding is that investigated wastewater services consumers perceive the effect of discharging untreated wastewater in the environment as highly negative both on human health and on the environment, thus pointing out the importance associated by them to water treatment. This research argues that understanding wastewater services consumer behaviour enlarges the way toward reducing environmental disturbances.

Diclofenac affects early embryo development in the marine bivalve Mytilus galloprovincialis

Diclofenac-DCF, one of the most widely prescribed non-steroidal anti-inflammatory drug, is globally detected in environmental compartments. Due to its occurrence in freshwater and potential impact on aquatic organisms, it has been added to the watch list of chemicals in the EU Water Directive; consequently, research on the impact of DCF in model aquatic organisms has great regulatory implications towards ecosystem health. DCF is also detected in coastal waters at concentrations from ng/L to 1 μg/L, as well as in marine organisms, such as the mussel Mytilus. Increasing evidence indicates that environmental concentrations of DCF have multiple impacts in adult mussels. Moreover, in M. galloprovincialis, DCF has been shown to affect early embryo development. The developmental effects of DCF in mussels were further investigated. DFC (1 and 10 μg/L) was added at different times post-fertilization (30 min and 24 hpf) and the effects were compared in the 48 hpf embryotoxicity assay. Shell mineralization and morphology were investigated by polarized light microscopy, X-Ray Spectrometry-XRD and Scanning Electron Microscopy-SEM. Transcriptional profiles of 12 selected genes physiologically regulated across early embryo development were assessed at 24 and 48 hpf. DCF induced shell malformations, irrespectively of concentration and time of exposure. DCF phenotypes were characterized by convex hinges, undulated edges, fractured shells. However, no changes in biomineralization were observed. DCF affected gene transcription at both times pf, in particular at 1 μg/L. The most affected genes were those involved in early shell formation (CS, CA, EP) and biotransformation (ABCB, GST). The results confirm that Mytilus early development represents a significant target for environmental concentrations of DCF. These data underline how the standard embryotoxicity assay, in combination with a structural and transcriptomic approach, represents a powerful tool for evaluating the early impact of pharmaceuticals on mussel embryos, and identification of the possible underlying mechanisms of action.

Cellular responses to in vitro exposures to β-blocking pharmaceuticals in hard clams and Eastern oysters

Increased consumption and improper disposal of prescription medication, such as beta (β)-blockers, contribute to their introduction into waterways and may pose threats to non-target aquatic organisms. There has been rising concern about the impacts of these prescription drugs on coastal ecosystems, especially because wastewater treatment plants are not designed to eliminate them from the discharge. Few studies have characterized the sublethal effects of β-blocker exposures in marine invertebrates. The overall aim of our research is to identify cellular responses of two commercially important filter-feeding marine bivalves, hard clams (Mercenaria mercenaria) and Eastern oysters (Crassostrea virginica), upon exposures to two β-blocker drugs, propranolol and metoprolol. In vitro exposures with bivalve digestive gland and gill tissues were conducted where tissues were separately exposed to each drug for 24 h. Tissue samples were analyzed for cellular damage (lysosomal membrane destabilization and lipid peroxidation), total antioxidant capacity, and glutathione-s-transferase activity. Elevated damage and changes in enzyme activities were noted in the exposed tissues at environmentally relevant concentrations. Differences in species and tissue sensitivities and responses to exposures were also observed. These studies enhance our understanding of the potential impacts of prescription medication on coastal organisms. Additionally, this work demonstrates that filter-feeders may serve as good model organisms to examine the effects of unintended environmental exposures to β-blockers. These studies are part of our ongoing work aimed at evaluation of sublethal biomarkers of pharmaceutical exposures and identification of key events that can contribute to the development of adverse outcome pathways (AOPs).

Screening of human and veterinary pharmaceuticals in estuarine waters: A baseline assessment for the Tejo estuary

We investigated the presence of 66 human and veterinary pharmaceuticals from seven therapeutic groups in surface waters of the Tejo estuary. Collection sites covered the entire estuary and included areas near main river inflows and wastewater treatment outfalls, traversing urban, agriculture, aquaculture, and nature reserve areas. Detection of pharmaceuticals was performed via UHPLC-TOF-MS. Pharmaceuticals were found in all sites (32 different compounds in total). Antibiotics, β-blockers, antihypertensives and anti-inflammatories were the most frequently detected (>90%), with variation in concentrations reflecting the multifaceted nature of estuarine surroundings (accumulated site contamination between 15 and 351 ng L^-1). Higher concentrations of antidepressant Sertraline (304 ng L^-1), non-steroidal anti-inflammatory Diclofenac (51.8 ng L^-1), lipid regulator Gemfibrozil (77.0 ng L^-1), antihypertensive Ibersartan (161.9 ng L^-1) or antibiotic Doxycycline (128.0 ng L^-1), among others, though localized may potentially impact key estuarine functions or services. Ultimately, results provide a baseline for regulatory information and future biota evaluations.

Synthesis and Phase Transformation Studies of Dysprosium-Doped Bi4V2O11 Nanoparticles and Their Application in Visible Light Photocatalytic Degradation of Tetracycline Drug

Recently, Bi₄V₂O₁₁ as an electrolyte material has pulled in considerable consideration because of its remarkable novel applications. In this article, novel, dysprosium-doped (x = 0.2, 0.3, 0.4, and 0.5) Bi₄V₂O₁₁ (Dy/BVO) nanoparticles have been synthesized by sol-gel strategy. The photocatalyst Dy/BVO nanoparticles exhibit higher photocatalytic efficiency than BVO nanoparticles assessed by debasement of tetracycline drug under visible light illumination. Our work focuses on the phase transformation, conducting properties, and mechanisms of the Dy/BVO nanoparticles in relation to execute some methods of processing and manufacturing product in commercial applications. The characterization of Dy/BVO was performed by Fourier transform infrared, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, and UV-vis analysis. ac impedance spectroscopy was used to analyze the conducting behavior of synthesized nanoparticles in the temperature range 100-600 °C. The photocatalytic activity revealed that Dy/BVO remarkably enhanced the photocatalytic activity. This is the first report that Dy/BVO can destroy the drug effluent which is coming from the drug industry and also worried about the human health hazards.

Anthropogenic Impacts on Meiosis in Plants

As the human population grows and continues to encroach on the natural environment, organisms that form part of such ecosystems are becoming increasingly exposed to exogenous anthropogenic factors capable of changing their meiotic landscape. Meiotic recombination generates much of the genetic variation in sexually reproducing species and is known to be a highly conserved pathway. Environmental stresses, such as variations in temperature, have long been known to change the pattern of recombination in both model and crop plants, but there are other factors capable of causing genome damage, infertility and meiotic abnormalities. Our agrarian expansion and our increasing usage of agrochemicals unintentionally affect plants via groundwater contamination or spray drift; our industrial developments release heavy metals into the environment; pathogens are spread by climate change and a globally mobile population; imperfect waste treatment plants are unable to remove chemical and pharmaceutical residues from sewage leading to the release of xenobiotics, all with potentially deleterious meiotic effects. In this review, we discuss the major classes of exogenous anthropogenic factors known to affect meiosis in plants, namely environmental stresses, agricultural inputs, heavy metals, pharmaceuticals and pathogens. The possible evolutionary fate of plants thrust into their new anthropogenically imposed environments are also considered.

Does exposure to reduced pH and diclofenac induce oxidative stress in marine bivalves? A comparative study with the mussel Mytilus galloprovincialis and the clam Ruditapes philippinarum

CO₂-driven acidification and emerging contaminants, such as pharmaceuticals, pose new threats for the maintenance of natural populations of marine organisms by interfering with their normal biochemical pathways and defences. The combined effects of seawater acidification, as predicted in climate change scenarios, and an emerging contaminant (the non-steroidal anti-inflammatory drug, NSAID, diclofenac) on oxidative stress-related parameters were investigated in the Mediterranean mussel Mytilus galloprovincialis and the Manila clam Ruditapes philippinarum. A flow-through system was used to carry out a three-week exposure experiment with the bivalves. First, the animals were exposed to only three pH values for 7 days. The pH was manipulated by dissolving CO₂ in the seawater to obtain two reduced pH treatments (pH -0.4 units and pH -0.7 units), which were compared with seawater at the natural pH level (8.1). Thereafter, the bivalves were concomitantly exposed to the three experimental pH values and environmentally relevant concentrations of diclofenac (0.00, 0.05 and 0.50 μg/L) for an additional 14 days. The activities of superoxide dismutase, catalase and cyclooxygenase, and lipid peroxidation and DNA strand-break formation were measured in both the gills and digestive gland after 7, 14 and 21 days of exposure to each experimental condition. The results show that the biochemical parameters measured in both the mussels and clams were more influenced by the reduced pH than by the contaminant or the pH*contaminant interaction, although the biomarker variation patterns differed depending on the species and tissues analysed. Generally, due to increases in its antioxidant defence, M. galloprovincialis was more resistant than R. philippinarum to both diclofenac exposure and reduced pH. Conversely, reduced pH induced a significant decrease in COX activity in both the gills and digestive gland of clams, possibly resulting in the increased DNA damage observed in the digestive gland tissue.

Integrated multi-biomarker responses of juvenile seabass to diclofenac, warming and acidification co-exposure

Pharmaceutical drugs, such as diclofenac (DCF), are frequently detected in the marine environment, and recent evidence has pointed out their toxicity to non-target marine biota. Concomitantly, altered environmental conditions associated with climate change (e.g. warming and acidification) can also affect the physiology of marine organisms. Yet, the underlying interactions between these environmental stressors (pharmaceutical exposure and climate change-related stressors) still require a deeper understanding. Comprehending the influence of abiotic variables on chemical contaminants' toxicological attributes provides a broader view of the ecological consequences of climate change. Hence, the aim of this study was to assess the ecotoxicological responses of juvenile seabass Dicenthrachus labrax under the co-exposure to DCF (from dietary sources, 500 ± 36 ng kg^-1 dw), warming (ΔTºC = +5 °C) and acidification (ΔpCO₂ ∼1000 μatm, equivalent to ΔpH = -0.4 units), using an "Integrated Biomarker Response" (IBR) approach. Fish were exposed to these three stressors, acting alone or combined, for 28 days in a full cross-factorial design, and blood, brain, liver and muscle tissues were subsequently collected in order to evaluate: i) animal/organ fitness; ii) hematological parameters and iii) molecular biomarkers. Results not only confirmed the toxicological attributes of dietary exposure to DCF in marine fish species at the tissue (e.g. lower HSI), cellular (e.g. increased ENAs and lower erythrocytes viability) and molecular levels (e.g. increased oxidative stress, protein degradation, AChE activity and VTG synthesis), but also showed that such attributes are altered by warming and acidification. Hence, while acidification and/or warming enhanced some effects of DCF exposure (e.g. by further lowering erythrocyte viability, and increasing brain GST activity and Ub synthesis in muscle), the co-exposure to these abiotic stressors also resulted in a reversion/inhibition of some molecular responses (e.g. lower CAT and SOD inhibition and VTG synthesis). IBRs evidenced that an overall higher degree of stress (i.e. high IBR index) was associated with DCF and warming co-exposure, while the effects of acidification were less evident. The distinct responses observed when DCF acted alone or the animals were co-exposed to the drug together with warming and acidification not only highlighted the relevance of considering the interactions between multiple environmental stressors in ecotoxicological studies, but also suggested that the toxicity of pharmaceuticals can be aggravated by climate change-related stressors (particularly warming), thus, posing additional biological challenges to marine fish populations.

Pharmaceuticals in the aquatic environments: Evidence of emerged threat and future challenges for marine organisms

Pharmaceuticals are nowadays recognized as a threat for aquatic ecosystems. The growing consumption of these compounds and the enhancement of human health in the past two decades have been paralleled by the continuous input of such biologically active molecules in natural environments. Waste water treatment plants (WWTPs) have been identified as a major route for release of pharmaceuticals in aquatic bodies where concentrations ranging from ng/L to μg/L are ubiquitously detected. Since medicines principles are designed to be effective at very low concentrations, they have the potential to interfere with biochemical and physiological processes of aquatic species over their entire life cycle. Investigations on occurrence, bioaccumulation and effects in non target organisms are fragmentary, particularly for marine ecosystems, and related to only a limited number over the 4000 substances classified as pharmaceuticals: hence, there is a urgent need to prioritize the environmental sustainability of the most relevant compounds. The aim of this review is to summarize the main adverse effects documented for marine species exposed in both field and laboratory conditions to different classes of pharmaceuticals including non-steroidal anti-inflammatory drugs, psychiatric, cardiovascular, hypocholesterolaemic drugs, steroid hormones and antibiotics. Despite a great scientific advancement has been achieved, our knowledge is still limited on pharmaceuticals behavior in chemical mixtures, as well as their interactions with other environmental stressors. Complex ecotoxicological effects are increasingly documented and multidisciplinary, integrated approaches will be helpful to clarify the environmental hazard of these "emerged" pollutants in marine environment.