The role of humic acids on gemfibrozil toxicity to zebrafish embryos.

Climate change is expected to alter the dynamics of water masses, with consequent changes in water quality parameters such as dissolved organic carbon (DOC) concentration. DOC levels play a critical role in the fate of organic chemicals, influencing their bioavailability and toxicity to aquatic organisms. This study aimed to evaluate the effects of DOC, particularly humic acids (HA), in the toxicity of gemfibrozil (GEM) - a human pharmaceutical frequently detected in surface waters. Lethal and sublethal effects (genotoxic, biochemical and behavioural alterations) were evaluated in zebrafish embryos exposed to several concentrations of GEM and three HA levels, in a full factorial design. HA significantly increased GEM LC50 values, mainly in the first 72 h of exposure, showing a protective effect. At sublethal levels, however, such protection was not observed since HA per se elicited adverse effects. At a biochemical level, individual exposure to HA (20 mg/L) elicited significant decreases in cholinesterase and glutathione S-transferase activities. Regarding behaviour, effects of individual exposure to HA appear to surpass the GEM effects, reducing the total distance moved by larvae. Both GEM and HA significantly increased DNA damage. Hence, this study demonstrated that abiotic factors, namely HA, should be considered in the assessment of pharmaceuticals toxicity. Moreover, it showed that lethality may not be enough to characterize combined effects since different patterns of response may occur at different levels of biological organization. Testing sublethal relevant endpoints is thus recommended to achieve a robust risk assessment in realistic scenarios.

Music festivals and drugs: Wastewater analysis.

Drug consumption in individual cities, regions, and at various music events and festivals across the EU has generally been monitored via questionnaires, patients' medical data, and police reports. However, an overview of drug consumption obtained from these methods can be negatively affected by various subjective factors. We aimed to investigate an association between levels of target drugs in wastewater, music genres, and festival courses. The occurrence of illicit drugs, their metabolites, and psychoactive compounds was investigated in the influent of six wastewater treatment plants in the Czech and Slovak Republic during seven large-scale music festivals from different music genres: metal, rock, pop, country and folk, ethnic, multi-genre, dance, and trance. The total number of participants included >130,000 active festival attendees. The association between music genre and illicit drug and/or psychoactive pharmaceutical consumptions is discussed on the basis of the results obtained through wastewater analyses. The observed trend was similar to worldwide published data with a specific local phenomenon of methamphetamine prevalence that did not significantly change between music events. Increased specific loads of cocaine (measured as its metabolite benzoylecgonine) and Ecstasy, along with some cannabis, were mainly observed during pop/rock and dance music festivals. However, there was no significant increase observed in the specific loads of all monitored psychoactive pharmaceuticals. This study demonstrates that the abuse of some illicit drugs is closely associated with specific music preferences.

Effects of Multi-Component Mixtures from Sewage Treatment Plant Effluent on Common Carp (Cyprinus carpio) under Fully Realistic Condition.

This study characterized changes in biomarker responses in common carp (Cyprinus carpio) upon exposure to effluent water discharged from a sewage treatment plant (STP) under real conditions. Fish were exposed to contamination in Cezarka pond, which receives all of its water input from the STP in the town of Vodnany, Czech Republic. Five sampling events were performed at day 0, 30, 90, 180, and 360 starting in April 2015. In total, 62 pharmaceutical and personal care products (PPCPs) were detected in the polar organic chemical integrative sampler. Compared to a control pond, the total concentration of PPCPs was 45, 16, 7, and 7 times higher in Cezarka pond at day 30, 90, 180, and 360, respectively. The result of oxidative stress and antioxidant enzyme biomarkers indicated alterations in the liver and intestine tissues of fish from Cezarka pond at day 30 and 360, respectively. High plasma vitellogenin levels were observed in both exposed females (180 and 360 days) and males (360 days) compared with their respective controls. However, only exposed female fish had higher vitellogenin mRNA expression than the control fish in these periods. Exposed female fish showed irregular structure of the ovary with scattered oocytes, which further developed to a vitellogenic stage at day 360. Low white blood cell levels were indicated in all exposed fish. Despite numerous alterations in exposed fish, favorable ecological conditions including high availability of food resulted in a better overall condition of the exposed fish after 1 year of exposure compared to the controls.

Correction to: Effects of multi-component mixtures from sewage treatment plant effluent on common carp (Cyprinus carpio) under fully realistic condition.

The original version of this Article unfortunately contained an error. The authors' given and family names were transposed erroneously. It has been corrected now in this Erratum.

Pharmaceuticals and illicit drugs - A new threat to the application of sewage sludge in agriculture.

The occurrence of 93 pharmaceuticals, illicit drugs and their metabolites has been investigated in stabilized sewage sludge from five municipal wastewater treatment plants (WWTPs) in the Slovak Republic. The total population connected to the tested WWTPs was approximately 600,000 p.e. which represents >20% of the Slovak population connected to public sewer systems. The sludge production from the five tested plants was >8100tons in 2016, which is approximately 15% of the total Slovak sewage sludge production in 2016. The highest total concentration of all pharmaceuticals was found in WWTP Bratislava Devínska Nová Ves (DNV) and Senec - 11,800 and 11,300ng/g dry matter (DM), respectively. Among individual pharmaceuticals, the highest concentrations were recorded for fexofenadine (mean 2340ng/g DM, maximum 5600ng/g DM in Bratislava DNV) and telmisartan (mean 1170ng/g DM, with a maximum of 3370ng/g DM in Senec). A principal component analysis revealed differences between pharmaceutical patterns in aerobically and anaerobically stabilized sludge. The worst-case scenario based on no further degradation of pharmaceuticals between sludge production and field application was used to predict pharmaceutical mass loads in agriculture. For the result, we estimated an annual load to soil in the Slovak Republic of up to several hundred kilograms of pharmaceuticals and drugs, with the maximum for fexofenadine (120kg/year) and verapamil (29kg/year).

Combined effects of insecticide exposure and predation risk on freshwater detritivores.

Insecticides usually present in low concentrations in streams are known to impair behaviour and development of non-target freshwater invertebrates. Moreover, there is growing awareness that the presence of natural stressors, such as predation risk may magnify the negative effects of pesticides. This is because perception of predation risk can by itself lead to changes on behaviour and physiology of prey species. To evaluate the potential combined effects of both stressors on freshwater detritivores we studied the behavioural and developmental responses of Chironomus riparius to chlorantraniliprole (CAP) exposure under predation risk. Also, we tested whether the presence of a shredder species would alter collector responses under stress. Trials were conducted using a simplified trophic chain: Alnus glutinosa leaves as food resource, the shredder Sericostoma vittatum and the collector C. riparius. CAP toxicity was thus tested under two conditions, presence/absence of the dragonfly predator Cordulegaster boltonii. CAP exposure decreased leaf decomposition. Despite the lack of significance for interactive effects, predation risk marginally modified shredder effect on leaf decomposition, decreasing this ecosystem process. Shredders presence increased leaf decomposition, but impaired chironomids performance, suggesting interspecific competition rather than facilitation. C. riparius growth rate was decreased independently by CAP exposure, presence of predator and shredder species. A marginal interaction between CAP and predation risk was observed regarding chironomids development. To better understand the effects of chemical pollution to natural freshwater populations, natural stressors and species interactions must be taken into consideration, since both vertical and horizontal species interactions play their role on response to stress.

Transport of pharmaceuticals and their metabolites between water and sediments as a further potential exposure for aquatic organisms.

Although pharmaceuticals are frequently studied contaminants, their fate in the environment is still not completely clear. During a one year study, a complex approach including water, sediment and fish sampling was used to describe the behaviour of pharmaceuticals and their metabolites (PTMs) in the environment. Eighteen pharmaceuticals and seven of their metabolites were determined in a pond used for the tertiary treatment of wastewater effluent. A liquid chromatography-tandem mass spectrometry method was applied to determine the PTMs concentrations in all matrices. Seasonal variations in concentrations were evaluated. The partitioning of contaminants between pond compartments was estimated by means of solid water distribution coefficients (Kd) and bioaccumulation factors (BAF) for the livers of fish. Kd values were almost stable throughout the year, which may be a sign of the continuous transport of PTMs between water and sediment under the experimental conditions. Almost all of the studied compounds, with exception of sertraline (BAF of 6200), were found to not be bioaccumulative in fish livers. The pond removal efficiency was calculated for all PTMs, and favourable conditions for natural pharmaceutical removal were proposed. Further aspects regarding fish pharmaceutical exposure need to be studied.

Sorption of citalopram, irbesartan and fexofenadine in soils: Estimation of sorption coefficients from soil properties.

The sorption of 3 pharmaceuticals, which may exist in 4 different forms depending on the solution pH (irbesartan in cationic, neutral and anionic, fexofenadine in cationic, zwitter-ionic and anionic, and citalopram cationic and neutral), in seven different soils was studied. The measured sorption isotherms were described by Freundlich equations, and the sorption coefficients, KF (for the fixed n exponent for each compound), were related to the soil properties to derive relationships for estimating the sorption coefficients from the soil properties (i.e., pedotransfer rules). The largest sorption was obtained for citalopram (average KF value for n = 1 was 1838 cm3 g-1) followed by fexofenadine (KF = 35.1 cm3/n µg1-1/n g-1, n = 1.19) and irbesartan (KF = 3.96 cm3/n µg1-1/n g-1, n = 1.10). The behavior of citalopram (CIT) in soils was different than the behaviors of irbesartan (IRB) and fexofenadine (FEX). Different trends were documented according to the correlation coefficients between the KF values for different compounds (RIRB,FEX = 0.895, p-value<0.01; RIRB,CIT = -0.835, p-value<0.05; RFEX,CIT = -0.759, p-value<0.05) and by the reverse relationships between the KF values and soil properties in the pedotransfer functions. While the KF value for citalopram was positively related to base cation saturation (BCS) or sorption complex saturation (SCS) and negatively correlated to the organic carbon content (Cox), the KF values of irbesartan and fexofenadine were negatively related to BCS, SCS or the clay content and positively related to Cox. The best estimates were obtained by combining BCS and Cox for citalopram (R2 = 93.4), SCS and Cox for irbesartan (R2 = 96.3), and clay content and Cox for fexofenadine (R2 = 82.9).

Comparison of passive sampling and biota for monitoring of tonalide in aquatic environment.

Synthetic musk compounds are extensively used in personal care and cosmetic products all over the world. Afterwards, they are discharged into the environment mainly because they are not completely removed in wastewater treatment plants. The aim of this study was to investigate if a passive sampler is applicable for the monitoring of tonalide, a polycyclic musk compound, in the aquatic environment and to compare the levels of tonalide in pesticide-polar organic chemical integrative sampler (POCIS) and biota. For this purpose, four sampling localities on the three biggest rivers in the Czech Republic were selected. Tonalide was determined in POCIS at all sampling sites in the concentration ranging from 9 ng/POCIS (Labe River, Hradec Králové) to 25 ng/POCIS (Morava River, Blatec). The locality with the most frequent occurrence of tonalide in biota samples was the Morava River which well corresponded with the highest tonalide concentration in POCIS among sampling sites. The highest number of positive tonalide detections among all studied biota samples was found in fish plasma. To the best of our knowledge, this is the first evidence that tonalide bioaccumulates in fish blood. Tonalide levels were below the limit of quantification in benthos samples at all sampling sites.

Removal of 30 active pharmaceutical ingredients in surface water under long-term artificial UV irradiation.

This study investigated the i) kinetics, and ii) proportion of photolysis of 30 relatively stable active pharmaceutical ingredients (APIs) during artificial UV irradiation for 28 d in ammonium acetate buffer, filtered and unfiltered river water. Buffer was included to control removal kinetics under stable pH conditions and without particulate matter. Dark controls were used to determine removal due to other processes than photolysis and calculate the proportion of photolysis of the total removal. The removal of each API in each matrix was determined using online solid phase extraction/liquid chromatography tandem mass spectrometry (online SPE/LC-MS/MS). Most APIs transformed during the 28 d of UV irradiation and the dark controls showed that photolysis was the major removal process for the majority of the APIs studied. The half-lives ranged from 6 h (amitriptyline) in unfiltered river water to 884 h (37 d, carbamazepine) in buffer. In unfiltered river water, the proportion of APIs with short half-lives (<48 h) was much higher (29%) than in the other matrices (4%), probably due to additional organic carbon, which could have promoted indirect photolysis. Furthermore, two APIs, memantine and fluconazole, were stable in all three matrices, while alprazolam was stable in buffer and unfiltered river water and four additional APIs were stable in buffer. Considering the relatively long-term UV-exposure, this study enabled the investigation of environmentally relevant half-lives in natural waters. Many APIs showed high persistence, which is environmentally concerning and emphasizes the importance of further studies on their environmental fate and effects.

Antibiotics degradation in soil: A case of clindamycin, trimethoprim, sulfamethoxazole and their transformation products.

Twelve different soil types that represent the soil compartments of the Czech Republic were fortified with three antibiotics (clindamycin (CLI), sulfamethoxazole (SUL), and trimethoprim (TRI)) to investigate their fate. Five metabolites (clindamycin sulfoxide (CSO), hydroxy clindamycin sulfoxide (HCSO), S-(SDC) and N-demethyl clindamycin (NDC), N4-acetyl sulfamethoxazole (N4AS), and hydroxy trimethoprim (HTR)) were detected and identified using HPLC/HRMS and HRPS in the soil matrix in this study. The identities of CSO and N4AS were confirmed using commercially available reference standards. The parent compounds degraded in all soils. Almost all of the metabolites have been shown to be persistent in soils, with the exception of N4AS, which was formed and degraded completely within 23 days of exposure. The rate of degradation mainly depended on the soil properties. The PCA results showed a high dependence between the soil type and behaviour of the pharmaceutical metabolites. The mentioned metabolites can be formed in soils, and the most persistent ones may be transported to the ground water and environmental water bodies. Because no information on the effects of those metabolites on living organism are available, more studies should be performed in the future to predict the risk to the environment.

Young-of-the-year fish as a prospective bioindicator for aquatic environmental contamination monitoring.

Toxic metals (Hg, Cd, Pb) and fifteen perfluoroalkyl substances (PFASs) were determined in different fish samples at two locations on the Elbe River in the Czech Republic. The muscle tissue of the two adult fish species most commonly used as bioindicators in central Europe and whole body homogenates of various species of young-of-the-year (YOY) fish were used. The purpose of this study was to evaluate the potential to replace adult fish muscle tissue with YOY fish for contamination monitoring. All of the toxic metals and five of the fifteen PFASs were found in the YOY fish samples while only mercury and PFOS were detected in the muscle tissue of adults. The concentration of total mercury (THg) in the YOY fish homogenates ranged between 0.014 and 0.062 µg g(-1). Of the spectrum of analysed pollutants, only the THg concentrations were lower in YOY fish homogenates than in adult muscle tissue. The cadmium concentration varied from 0.004 to 0.024 µg g(-1) and the lead concentration varied from 0.032 to 0.396 µg g(-1) in YOY fish homogenates, while in most of the adult samples, Cd and Pb were below the detection limit of the analytical methods employed. The PFOS concentrations in YOY fish homogenates were comparable to the concentrations frequently found in adult liver tissue. These results show that mixed shoals of YOY fish can be successfully used for aquatic bio-monitoring. Interspecific variability in the concentrations of the target pollutants in YOY fish whole body homogenates is usually lower than the intraspecific variability of the concentrations of the pollutants in adult fish muscle. YOY fish were found to be a suitable bioindicator and have several advantages compared to adult fish.

Transformation of atenolol, metoprolol, and carbamazepine in soils: The identification, quantification, and stability of the transformation products and further implications for the environment.

Pharmaceuticals are a large group of substances that have been recognized as environmental contaminants in recent years. Research on the pharmaceutical fate in soils is currently limited or missing. In this study, three pharmaceuticals (atenolol (ATE), carbamazepine (CAR), and metoprolol (MET)) were introduced to soils and exposed for 61 day under aerobic conditions. Thirteen different soils were used in the study to increase the understanding of pharmaceutical behaviour in the soil matrix. Ten metabolites were detected and tentatively identified. Some of them, such as atenolol acid (AAC), carbamazepine 10,11-epoxide (EPC), 10,11-dihydrocarbamazepine (DHC), trans-10,11-Dihydro-10,11-dihydroxy carbamazepine (RTC), and metoprolol acid (MAC), were consequently confirmed using commercial reference standards. It was concluded that the aerobic conditions of the experiment determined the pharmaceutical degradation pathway of studied compounds in the soils. The different amounts/rates and degradation of the transformation products can be attributed to differences in the soil properties. ATE degraded relatively quickly compared with CAR, whereas MET degradation in the soils was unclear. The persistence of CAR and its metabolites, in combination with low CAR sorption, enable the transportation of CAR and its metabolites within soils and into the ground water. Thus, CAR may cause adverse effects on the environment and humans.

Investigation of diltiazem metabolism in fish using a hybrid quadrupole/orbital trap mass spectrometer.

RATIONALE: Diltiazem, a calcium channel blocker drug, is widespread in the environment because of its incomplete elimination during water treatment. It can cause negative effects on aquatic organisms; thus, a rapid and sensitive liquid chromatography/mass spectrometry (LC/MS) method to detect its presence was developed. Our approach is based on accurate mass measurements using a hybrid quadrupole-orbital trap mass spectrometer that was used to measure diltiazem and its metabolites in fish tissue. METHODS: Blood plasma, muscle, liver, and kidney tissues of rainbow trout (Oncorhynchus mykiss), exposed for 42 days to 30 µg L(-1) diltiazem, were used for the method development. No metabolite standards were required to identify the diltiazem biotransformation products in the fish tissue. RESULTS: Overall, 17 phase I diltiazem metabolites (including isomeric forms) were detected and tentatively identified using the MassFrontier spectral interpretation software. A semi-quantitative approach was used for organ-dependent comparison of the metabolite concentrations. CONCLUSIONS: These data increase our understanding about diltiazem and its metabolites in aquatic organisms, such as fish. These encompass desmethylation, desacetylation and hydroxylation as well as their combinations. This study represents the first report of the complex diltiazem phase I metabolic pathways in fish.

Development of fast and robust multiresidual LC-MS/MS method for determination of pharmaceuticals in soils.

The aim of this study was to develop a simple extraction procedure and a multiresidual liquid chromatography-tandem mass spectrometry method for determination of a wide range of pharmaceuticals from various soil types. An extraction procedure for 91 pharmaceuticals from 13 soil types, followed by liquid chromatography-tandem mass spectrometry analysis, was optimized. The extraction efficiencies of three solvent mixtures for ultrasonic extraction were evaluated for 91 pharmaceuticals. The best results were obtained using acetonitrile/water (1/1 v/v with 0.1 % formic acid) followed by acetonitrile/2-propanol/water (3/3/4 v/v/v with 0.1 % formic acid) for extracting 63 pharmaceuticals. The method was validated at three fortification levels (10, 100, and 1000 ng/g) in all types of representative soils; recovery of 44 pharmaceuticals ranged between 55 and 135 % across all tested soils. The method was applied to analyze actual environmental samples of sediments, soils, and sludge, and 24 pharmaceuticals were found above limit of quantification with concentrations ranging between 0.83 ng/g (fexofenadine) and 223 ng/g (citalopram).

Are insect repellents toxic to freshwater insects? A case study using caddisflies exposed to DEET.

Stream ecosystems face ever-increasing pressures by the presence of emergent contaminants, such as, personal care products. N, N-diethyl-3-methylbenzamide (DEET) is a synthetic insect repellent that is being found in surface waters environments in concentrations up to 33.4 µg/L. Information concerning DEET's toxicity in the aquatic environment is still limited and focused only on its acute effects on model species. Our main objective was to assess the effects of DEET exposure to a caddisfly non-target species using sub-lethal endpoints. For that, we chose Sericostoma vittatum, an important shredder in Portuguese freshwaters that has been already used in different ecotoxicological assays. Besides acute tests, S. vittatum were exposed during 6 days to a gradient of DEET concentrations (8, 18 and 40.5 mg/L) to assess effects on feeding behaviour and biochemical responses, such as, lipid peroxidation levels (LPO), catalase and acetylcholinesterase (AChE) activities, and also assess effects on energy reserves and consumption. Acute tests revealed a 48 h-LC50 of 80.12 mg/L and DEET exposure caused feeding inhibition with a LOEC of 36.80 mg/L. Concerning the biochemical responses, DEET caused no effects in LPO nor on catalase activity. A non-significant decrease in AChE activity was observed. Regarding energetic reserves, exposure to DEET caused a significant reduction in S. vittatum carbohydrates levels. These results add important information for the risk assessment of insect repellents in the aquatic environment and suggest that reported environmental concentrations of DEET are not toxic to non-target freshwater insects.

Bioconcentration, metabolism and half-life time of the human therapeutic drug diltiazem in rainbow trout Oncorhynchus mykiss.

Diltiazem is a human therapeutic drug and a member of the group of calcium channel blockers having widespread use in the treatment of angina pectoris and hypertension. The objective of the present study was to assess the bioconcentration, metabolism, and half-life time of diltiazem in rainbow trout Oncorhynchus mykiss. Juvenile trout were exposed for 21 and 42 days to three nominal concentrations of diltiazem: 0.03 µg L(-1) (environmentally relevant concentration), 3 µg L(-1), and 30 µg L(-1) (sub-lethal concentrations). The bioconcentration factor (BCF) of diltiazem was relatively low (0.5-194) in analysed tissues, following the order kidney > liver > muscle > blood plasma. The half-life of diltiazem in liver, kidney, and muscle was 1.5 h, 6.2 h, and 49 h, respectively. The rate of metabolism for diltiazem in liver, kidney, muscle, and blood plasma was estimated to be 85 ± 9%, 64 ± 14%, 46 ± 6%, and 41 ± 8%, respectively. Eight diltiazem metabolites were detected. The presence of desmethyl diltiazem (M1), desacetyl diltiazem (M2), and desacetyl desmethyl diltiazem (M3) suggests that rainbow trout metabolize diltiazem mainly via desmethylation and desacetylation, similar to mammals. In addition, diltiazem undergoes hydroxylation in fish. At environmentally relevant concentrations, diltiazem and its metabolites were identified in liver and kidney, indicating the potential for uptake and metabolism in non-target organisms in the aquatic environment.

An analysis of the dissipation of pharmaceuticals under thirteen different soil conditions.

The presence of human and veterinary pharmaceuticals in the environment is recognized as a potential threat. Pharmaceuticals have the potential to contaminate soils and consequently surface and groundwater. Knowledge of contaminant behavior (e.g., sorption onto soil particles and degradation) is essential when assessing contaminant migration in the soil and groundwater environment. We evaluated the dissipation half-lives of 7 pharmaceuticals in 13 soils. The data were evaluated relative to the soil properties and the Freundlich sorption coefficients reported in our previous study. Of the tested pharmaceuticals, carbamazepine had the greatest persistence (which was mostly stable), followed by clarithromycin, trimethoprim, metoprolol, clindamycin, sulfamethoxazole and atenolol. Pharmaceutical persistence in soils was mostly dependent on the soil-type conditions. In general, lower average dissipation half-lives and variability (i.e., trimethoprim, sulfamethoxazole, clindamycin, metoprolol and atenolol) were found in soils of better quality (well-developed structure, high nutrition content etc.), and thus, probably better microbial conditions (i.e., Chernozems), than in lower quality soil (Cambisols). The impact of the compound sorption affinity onto soil particles on their dissipation rate was mostly negligible. Although there was a positive correlation between compound dissipation half-life and Freundlich sorption coefficient for clindamycin (R=0.604, p<0.05) and sulfamethoxazole (R=0.822, p<0.01), the half-life of sulfamethoxazole also decreased under better soil-type conditions. Based on the calculated dissipation and sorption data, carbamazepine would be expected to have the greatest potential to migrate in the soil water environment, followed by sulfamethoxazole, trimethoprim and metoprolol. The transport of clindamycin, clarithromycin and atenolol through the vadose zone seems less probable.

Carbendazim exposure induces developmental, biochemical and behavioural disturbance in zebrafish embryos.

Carbendazim is a widely used broad spectrum benzimidazole fungicide; however, its effects to non-target aquatic organisms are poorly studied. The aim of this study was to investigate the toxic effects of carbendazim to zebrafish early life stages at several levels of biological organization, including developmental, biochemical and behavioural levels. The embryo assay was done following the OECD guideline 236 and using a concentration range between 1.1 and 1.8mg/L. Lethal and developmental endpoints such as hatching, edemas, malformations, heart beat rate, body growth and delays were assessed in a 96h exposure. A sub-teratogenic range (from 0.16 to 500µg/L) was then used to assess effects at biochemical and behavioural levels. Biochemical markers included cholinesterase (ChE), glutathione-S-transferase (GST), lactate dehydrogenase (LDH) and catalase (CAT) and were assessed at 96h. The locomotor behaviour was assessed using an automated video tracking system at 120h. Carbendazim (96h-LC50 of 1.75mg/L) elicited several developmental anomalies in zebrafish embryos with EC50 values ranging from 0.85 to 1.6mg/L. ChE, GST and LDH activities were increased at concentrations equal or above 4µg/L. The locomotor assay showed to be extremely sensitive, detecting effects in time that larvae spent swimming at concentrations of 0.16µg/L and thus, being several orders of magnitude more sensitive that developmental parameters or lethality. These are ecological relevant concentrations and highlight the potential of behavioural endpoints as early warning signs for environmental stress. Further studies should focus on understanding how the behavioural disturbances measured in these types of studies translate into fitness impairment at the adult stage.