Coastal areas are continually impacted by anthropic activities because they shelter large urban conglomerates. Urban effluents directly or indirectly end up reaching the marine environment, releasing ...a large number of pollutants which include the so-called contaminants of emerging concern (CECs), since the conventional treatment plants are not effective in removing these compounds from the effluents. These substances include hormones, pharmaceuticals and personal care products, nanoparticles, biocides, among others. The aim of this study was to evaluate the toxicity of the 17α-ethinylestradiol (EE2), acetylsalicylic acid (ASA), and bisphenol-A (BPA) to two marine crustaceans and one echinoderm, evaluating the following parameters: survival (
Artemia
sp. and
Mysidopsis juniae
), embryo-larval development (
Echinometra lucunter
). The LC
50
values calculated in the acute toxicity tests showed that the compounds were more toxic to
M. juniae
than to the
Artemia
sp. Among the three contaminants, EE2 was the most toxic (LC
50-48h
= 18.4 ± 2.7 mg L
−1
to
Artemia
sp.; LC
50-96h
= 0.36 ± 0.07 mg L
−1
to
M. juniae
). The three tested compounds affected significantly the embryonic development of the sea urchin in all tested concentrations, including ecologically relevant concentrations, indicating the potential risk that these contaminants may present to the marine biota.
The Rodrigo de Freitas Lagoon (RFL - Rio de Janeiro, RJ, Brazil) is a highly polluted and eutrophic lacustrine system, which has been often used for the practice of aquatic sports, including during ...the 2016 Summer Olympic Games. This study proposes the evaluation of metal concentrations in surface sediments from the RFL before and after urban interventions performed for the 2016 Olympics, as well as their toxicity to the benthic amphipod Tiburonella viscana and embryos of the sea-urchin Echinometra lucunter. Metal concentrations determined in 2017 were significantly higher than those obtained in 2015 (especially Cu, Cd and Ni), suggesting that the interventions performed to fulfill the requirements of the Olympics increased metal contents in sediments. The sediments from the northern sector of the RFL were muddier, more organically enriched, exhibited higher metal concentrations and were more toxic to T. viscana when compared to the sediments collected in the southern sector. This fact is particularly important since the practice of sports, including during the 2016 Olympics, has been preferably performed in the northern sector. Metal distribution was strongly correlated with organic matter and mud contents. The toxicity to E. lucunter embryos was high for both northern and southern sediments; most of the samples led to 100% lack or abnormal embryonic development. The integration of physical, chemical and ecotoxicological data indicates that the mortality to T. viscana was correlated with metal contents, whereas the toxicity to E. lucunter was apparently related to the release of ammonia from the sediment to water column. Finally, high metal concentrations and the toxicity to aquatic organisms evidence the ecological risks to the biota from RFL.
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•Sediments from Rodrigo de Freitas Lagoon are highly metal polluted.•Metal concentrations in sediments were higher after urban interventions for the 2016 Olympic Games.•Sediments were toxic to amphipods and embryos of sea urchin.
High metal concentrations and the toxicity to aquatic organisms evidence the ecological risks to the biota from Rodrigo de Freitas Lagoon (Rio de Janeiro – Brazil).
This review presents a comprehensive compilation of toxicological and environmental data, further used to assess the ecological risk (ERA) of the 11 EU approved antifouling biocides (PT21). Diuron, ...chlorothalonil, DCOIT, and pyrithiones are amongst the most toxic biocides toward producer species, while, CuSCN, medetomidine, and zineb showed higher toxicity toward consumers. In addition, medetomidine, CuSNC, zineb, Cu
2
O, and chlorothalonil are up to 400-fold more toxic to non-target organisms than target organisms highlighting their potential threat for marine ecosystems. Biocides hazard, which was assessed based on the marine PNEC
probabilistic
for biocides having enough and reliable ecotoxicological data, can be summarized in the following order: ZnPT (more hazardous) > CuPT > DCOIT > diuron > chlorothalonil > dichlofluanid > tolylfluanid. For the remaining biocides, the marine hazard was calculated based on the PNEC
deterministic
as follows: CuSCN (more hazardous) > Cu
2
O > medetomidine > zineb. The risk assessment indicates that the following biocides poses risk (quotient >1) for the coastal ecosystems: DCOIT, diuron, dichlofluanid, chlorothalonil, CuSCN, Cu
2
O, medetomidine and zineb. In order to protect the services and functions of coastal environments, a systematic and continuous monitoring of these biocides in coastal areas are highly recommended. Current regulatory framework and the replacement of state-of-the-art biocides by safer alternative is also critically discussed.
Urban waste is a complex mixture of different substances, including microplastics and pharmaceuticals and personal care products. Microplastics have a high affinity for hydrophobic substances. One of ...these substances is triclosan, a bactericide used in a variety of hygiene products. Therefore, microplastics (MPs) may serve as a vector between triclosan and aquatic organisms. The current study sought to evaluate the effects of the interaction between microplastics and triclosan based on a mechanistic approach in which the oyster
Crassostrea brasiliana
was used as a model. The organisms were exposed to three conditions: the control, microplastic (MP), and microplastic contaminated with triclosan (MPT). The organisms were exposed for 3 or 7 days. After the exposure time, hemolymph was sampled for performing the neutral red retention time assay and, subsequently, the gills, digestive glands, and adductor muscles were dissected for measuring biomarkers responses (EROD, DBF, GST, GPx, GSH, lipid peroxidation, DNA strand breaks, and AChE). Our results demonstrate combined effects of MPs associated with triclosan on oyster physiology and biochemistry, as well as on lysosomal membrane stability. These results contribute to understanding the effects of contaminants of emerging concern and microplastics on aquatic organisms.
Currently, several concerns have been raised over metal contamination in the upper Amazon basin. Rivers that flow from the high Andes to the lowland Amazon are threatened by anthropogenic activities, ...which may, in turn, lead to increased metal concentrations in both water and sediments. In the present study, the impacts of multiple metal contamination sources in these ecosystems were identified. The degree of metal contamination was assessed in water and sediment and seed phytotoxicity analyses were carried out in samples taken from 14 sites located in upper Napo River tributaries, combining geochemical and ecotoxicological techniques. These tributaries were chosen based on their degree of anthropogenic contamination and proximity to known sources of relevant pollution, such as small-scale gold mining (MI), urban pollution (UP), fish farming (FF) and non-functional municipal landfill areas (LF). Our results suggest that anthropogenic activities are introducing metals to the aquatic ecosystem, as some metals were up to 500 times above the maximum permissible limits for the preservation of aquatic life established by Ecuadorian and North American guidelines. Sites located close to small-scale gold mining and sanitary landfills presented 100 to 1000 times higher concentrations than sites classified as “few threats”. In water, Cd, Pb, Cu, Zn and Hg were mostly above the maximum permissible limits in the samples, while Cd in sediment reached concentrations 5-fold above the probable effect level (PEL). Phytotoxicity was associated through the diffuse contamination present in urban and landfill areas. Overall, metal concentrations and phytotoxicity assessments suggest anthropogenic effects to environmental contamination, even though natural sources cannot be disregarded. Anthropogenic effects in the eastern Andean Rivers need to be constantly monitored in order to build a complete picture on how pollution sources may affect this strategic Amazon basin area.
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•Point pollution sources are significant sources of metal, including landfills, small-scale mining and fish farming.•Hg and Cd originated from both natural and anthropogenic sources.•Phytotoxicity was related to diffuse sources (urban pollution and landfill).
Recent advances in nanotechnology have allowed the encapsulation of hazardous antifouling (AF) biocides in silica mesoporous nanocapsules (SiNC) reducing their short-term toxicity. However, the ...chronic effects of such novel nanoadditives remain understudied. The present study aimed to assess short- and long-term sub-lethal effects of soluble forms (DCOIT and Ag) and nanostructured forms (SiNC-DCOIT and SiNC-DCOIT-Ag) of two AF biocides and the “empty” nanocapsule (SiNC) on juveniles of
Crassostrea gigas
after 96 h and 14 days of exposure. Juvenile oysters exposed for a short period to free DCOIT and AgNO
3
presented worse physiological status comparing with those exposed to the nanostructured forms. The long-term exposure to DCOIT and Ag
+
caused an extensive biochemical impairment comparing with the tested nanomaterials, which included oxidative damage, activation of the antioxidant defense system, and neurotransmission impairment. Despite the negative effects mostly observed on the health condition index and AChE, the encapsulation of the abovementioned AF biocides into SiNC seems to be a technological advantage towards the development of AF nanoadditives with lower long-term toxicity comparing with the soluble forms of such biocides.
Sedimentary aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were studied in subtropical estuaries with distinct degrees of legal protection, located in the Southwestern Atlantic ...Ocean, São Paulo State, Brazil. A multivariate approach was adopted, using the Hierarchical cluster analysis followed by the Principal Matrix Factorization analysis to support the hydrocarbons sources findings using diagnostic ratios. In general, the sites with the highest values of hydrocarbons were in the vicinity of well-urbanized cities, where sewage discharge, harbor and industrial activities take place. Pyrolitic PAHs were the predominant source of PAHs in the sites. The region can be considered not highly contaminated by hydrocarbons; however, specific sites under local anthropogenic impact from sewage and/or urban drainage, presented relatively high hydrocarbons levels. These findings highlight the importance of sources identification as reliable approach to be included in the management plan of protected areas under the inputs of several vectors of contamination.
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•Hydrocarbon's levels and toxicity data indicate risks in the studied marine areas.•Aliphatic hydrocarbons levels related to accumulation generated by hydrodynamic factors•High levels of aliphatic hydrocarbons related to sewage inputs in the winter season•Predominance of pyrogenic polycyclic aromatic hydrocarbons detected in the sediments•Sources of contaminants are mainly in the vicinity of well-urbanized regions.
Pharmaceutical discharges into the aquatic ecosystem are of environmental concern and sewage treatment plants (STPs) have been pointed out as the major source of these compounds to coastal zones, ...where oceanic disposal of sewage occurs through submarine outfalls. Diclofenac (DCF) is one of the most frequently detected pharmaceuticals in water, but little is known about the effects on marine organisms. In this study, we employed a tiered approach involving the determination of environmental concentrations of DCF in marine water and the adverse biological effects for fertilization, embryo-larval development and biomarker responses of the mussel Perna perna. Results indicate that effects in fertilization rate and embryo-larval development were found in the order of mg·L−1. However, low concentrations of DCF (ng·L−1) significantly decreased the lysosomal membrane stability and COX activity, as well as triggered DNA damage, oxidative stress and changes in antioxidant defenses. Our results point to an environmental hazard at coastal ecosystems and suggest the need for improvements in the treatment of domestic wastewater aiming to reduce DCF concentrations, as well as regulation on current environmental legislation and monitoring of aquatic ecosystems.
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•Toxicity to gametes and embryos exposed to Diclofenac.•Cyto-genotoxicity in adult mussels exposed to ng·L-1 levels.•Similar mode of action in a non-target organism.•Adverse effects at environmentally relevant concentrations.
The antihypertensive losartan (LOS) has been detected in wastewater and environmental matrices, however further studies focused on assessing the ecotoxicological effects on aquatic ecosystems are ...necessary. Considering the intensive use of this pharmaceutical and its discharges into coastal zones, our study aimed to determine the environmental concentrations of LOS in seawater, as well as to assess the biological effects of LOS on the marine bivalve Perna perna. For this purpose, fertilization rate and embryolarval development were evaluated through standardized assays. Phase I (ethoxyresorufin O‑deethylase EROD and dibenzylfluorescein dealkylase DBF) and II (glutathione S-transferase GST) enzymes, glutathione peroxidase (GPx), Cholinesterase (ChE), lipoperoxidation (LPO) and DNA damage were used to analyze sublethal responses in gills and digestive gland of adult individuals. Lysosomal membrane stability was also assessed in hemocytes. Our results showed the occurrence of LOS in 100% of the analyzed water samples located in Santos Bay, Sao Paulo, Brazil, in a range of 0.2 ng/L–8.7 ng/L. Effects on reproductive endpoints were observed after short-term exposure to concentrations up to 75 mg/L. Biomarker responses demonstrated the induction of CYP450 like activity and GST in mussel gills exposed to 300 and 3000 ng/L of LOS, respectively. GPx activity was also increased in concentration of exposure to 3000 ng/L of LOS. Cyto-genotoxic effects were found in gills and hemocytes exposed in concentrations up to 300 ng/L. These results highlighted the concern of introducing this class of contaminants into marine environments, and pointed out the need to include antihypertensive compounds in environmental monitoring programs.
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•Losartan concentrations in seawater from Santos bay ranged from 0.2 to 8.6 ng/L.•Reproductive parameters were altered after acute exposure up to 75 mg/L.•Cyto-genotoxic effects observed after short-term exposure (48–96 h) to ng/L•Perna perna is a sensitive model for assessing losartan toxicity.•Lysosomal membrane stability was the most sensitive endpoint.
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