Yttrium effects on the Mediterranean mussel under a scenario of salinity shifts and increased temperature.

Climate change (CC) induces significant worldwide alterations in salinity and temperature, impacting ecosystems and their services. Marine organisms, susceptible to these changes, may experience modified vulnerability to anthropogenic contaminants, including rare-earth elements (REEs) such as yttrium (Y) derived from electronic waste. This study investigated the influence of temperature and salinity changes on the impacts of Y in Mytilus galloprovincialis mussels. Organisms were subjected to Y (0 and 10 µg/L) for 28 days under three salinity scenarios (20, 30 (control), and 40, at a control temperature of 17 °C) or to two temperatures (17 and 22 °C, at the control salinity of 30). Under these conditions, Y bioaccumulation and different biomarkers were evaluated. Results showed that salinity and temperature did not affect Y accumulation, indicating effective detoxification mechanisms and physiological adaptations in the exposed organisms. However, in Y-exposed mussels effects were intensified under decreased salinity, evidenced by increased metabolism, defense enzyme activities, and acetylcholinesterase (AChE) levels. Similar responses occurred under heat stress with enhanced metabolic capacity, AChE activity, and activation of defense mechanisms such as glutathione S-transferases. These defense mechanisms mitigated cellular damage caused by Y, but under the highest temperature and especially lower salinity, Y-exposed mussels exhibited increased oxidative stress and decreased efficiency of activated defense enzymes, resulting in cellular damage compared to their uncontaminated counterpart. The present study sheds light on the effects that interactions between temperature, salinity, and the presence of emerging contaminants like REEs may have on marine organisms. Such assessments are crucial for developing effective strategies to mitigate the impacts of CC and protect the long-term health and resilience of marine ecosystems.

How predicted temperature and salinity changes will modulate the impacts induced by terbium in bivalves?

The threat of climate change, which includes shifts in salinity and temperature, has generated a global concern for marine organisms. These changes directly impact them and may alter their susceptibility to contaminants, such as terbium (Tb), found in electronic waste. This study assessed how decreased and increased salinity, as well as increased temperature, modulates Tb effects in Mytilus galloprovincialis mussels. After an exposure period of 28 days, Tb bioaccumulation and biochemical changes were evaluated. Results indicated no significant modulation of salinity and temperature on Tb accumulation, suggesting detoxification mechanisms and adaptations. Further analysis showed that Tb exposure alone caused antioxidant inhibition and neurotoxicity. When exposed to decreased salinity, these Tb-exposed organisms activated defense mechanisms, a response indicative of osmotic stress. Moreover, increased salinity also led to increased oxidative stress and metabolic activity in Tb-exposed organisms. Additionally, Tb-exposed organisms responded to elevated temperature with altered biochemical activities indicative of damage and stress response. Such responses suggested that Tb effects were masked by osmotic and heat stress. This study provides valuable insights into the interactions between temperature, salinity, and contaminants such as Tb, impacting marine organisms. Understanding these relationships is crucial for mitigating climate change and electronic waste effects on marine ecosystems.

Sources of persistent organic pollutants and their physiological effects on opportunistic urban gulls.

Urbanization is associated with drastic shifts in biodiversity. While some species thrive in urban areas, the impact of inhabiting these human-altered environments on organism physiology remains understudied. We investigated how exposure to polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) affects the physiology of yellow-legged gulls (Larus michahellis) inhabiting a densely populated, industrialized city. We analyzed blood samples from 50 gulls (20 immatures and 30 adults) and assessed 27 physiological parameters and biomarkers related to xenobiotic protection, health, and feeding habits in these same individuals. We also tracked the movements of 25 gulls (15 immatures and 10 adults) to identify potential sources of persistent organic pollutants (POPs). Both adult and immature gulls primarily inhabited urban areas, followed by marine habitats. Immature gulls spent more time in freshwater, landfills, and agricultural areas. Bioaccumulated ΣPCB (median = 92.7 ng g-1 ww, 1.86-592) and ΣPBDE (median = 1.44 ng g-1 ww, 0.022-9.58) showed no significant differences between age and sex groups. Notably, immature males exhibited the highest correlations with POP concentrations, particularly with the activity of carboxylesterases (CEs), suggesting a higher sensitivity than adults. These findings highlight the potential of plasmatic CEs in immature yellow-legged gulls as effective tracers of POPs exposure and effects, offering insights into the anthropogenic impacts on urban biodiversity.

Gadolinium accumulation and its biochemical effects in Mytilus galloprovincialis under a scenario of global warming.

Electrical and electronic equipment reaching the end of its useful life is currently being disposed of at such an alarmingly high pace that raises environmental concerns. Together with other potentially dangerous compounds, electronic waste contains the rare-earth element gadolinium (Gd), which has already been reported in aquatic systems. Additionally, the vulnerability of aquatic species to this element may also be modified when climate change related factors, like increase in temperature, are taken into consideration. Thus, the present study aimed to evaluate the toxicity of Gd under a scenario of increased temperature in Mytilus galloprovincialis mussels. A multi-biomarker approach and Gd bioaccumulation were assessed in mussels exposed for 28 days to 0 and 10 µg/L of Gd at two temperatures (control - 17 °C; increased - 22 °C). Results confirmed that temperature had a strong influence on the bioaccumulation of Gd. Moreover, mussels exposed to Gd alone reduced their metabolism, possibly to prevent further accumulation, and despite catalase and glutathione S-transferases were activated, cellular damage seen as increased lipid peroxidation was not avoided. Under enhanced temperature, cellular damage in Gd-exposed mussels was even greater, as defense mechanisms were not activated, possibly due to heat stress. In fact, with increased temperature alone, organisms experienced a general metabolic depression, particularly evidenced in defense enzymes, similar to the results obtained under Gd-exposure. Overall, this study underlines the importance of conducting environmental risk assessment taking into consideration anticipated climate change scenarios and exposures to emerging contaminants at relevant environmental concentrations.

Assessing the impact of terbium on Mytilus galloprovincialis: Metabolic and oxidative stress responses.

The increasing demand for electric and electronic equipment has led to a rise in potentially hazardous electronic waste, including rare-earth elements (REEs), such as terbium (Tb), which have been already detected in aquatic systems. This study investigated the biochemical effects of anthropogenic Tb on mussels over a 28-day period. The mussels were exposed to different concentrations of Tb (0, 5, 10, 20, 40 µg/L), and biomarkers related to metabolism, oxidative stress, cellular damage, and neurotoxicity were evaluated. Bioaccumulation of Tb in the mussels' tissue increased with exposure concentrations, but the bioconcentration factor remained similar between treatments. Exposure to Tb enhanced glycogen consumption and decreased metabolic capacity which could be seen as a physiological adaptation to limit Tb accumulation. Antioxidant defenses and glutathione S-transferases showed a more complex dose-response, with enzymatic responses increasing until 10 µg/L but then returning to control levels at 20 µg/L. At 40 µg/L, enzymatic responses were also enhanced but to a lower extent than at 10 µg/L. The presence of Tb had clearly an inhibitory effect on biotransformation enzymes such as carboxylesterases in a dose-dependent manner. Likely, thanks to biochemical and physiological adaptations, no cellular damage or neurotoxicity was observed in any treatments, confirming the mussels' ability to tolerate Tb exposure. Nevertheless, prolonged exposure to these concentrations could lead to harmful consequences when facing other environmental stressors, such as misallocating energy resources for growth, reproduction, and defense mechanisms.

The influence of ecological factors in the modulation of pollution biomarkers of two small pelagic marine fish.

Biomarkers are useful tools for the detection of marine pollution, which is poorly monitored in the pelagic environment. In this study, we investigated the role of key biological and environmental factors on three hepatic xenobiotic biomarkers: carboxylesterases (CEs), glutathione S-transferase (GST) and catalase (CAT). Additionally, ethoxyresorufin-O-deethylase (EROD) and benzyloxy-4-[trifluoromethyl]-coumarin-O-debenzyloxylase (BFCOD) activities were determined for comparative purposes. The pelagic species targeted were the European anchovy (Engraulis encrasicolus) and the European sardine (Sardina pilchardus). The results revealed sex-dependent CE activities in sardine. CEs and GST activities were significantly affected by reproduction and, in anchovy, CE activities were also influenced by temperature. In vitro incubations revealed that the pesticide dichlorvos caused up to 90 % inhibition of basal CEs activity. This work highlights that the reproductive status, temperature and sex, modulate biomarker responses, and that anchovy would be more suitable pelagic bioindicator due to its higher in vitro sensitivity to dichlorvos and sex-independent biomarker responses.

Threats of Pollutants Derived from Electronic Waste to Marine Bivalves: The Case of the Rare-Earth Element Yttrium.

The production of electrical and electronic equipment waste (e-waste) is increasing at an alarming rate worldwide. This may eventually lead to its accumulation in aquatic environments, mainly because of the presence of nonbiodegradable components. The rare-earth element yttrium (Y) is particularly relevant because it is present in a wide variety of electro-based equipment. Within this context, the present study investigated the biological consequences of anthropogenic Y exposure in Mytilus galloprovincialis. Mussels were exposed to Y (0, 5, 10, 20, 40 µg/L) for 28 days, and their bioaccumulation and biomarkers related to metabolism, oxidative stress defenses, cellular damage, and neurotoxicity were evaluated. The results revealed that tissue Y content increased at increasing exposure concentrations (though the bioconcentration factor decreased). At the lowest Y dosage (5 µg/L), mussels lowered their electron transport system (ETS) activity, consumed more energy reserves (glycogen), and activated superoxide dismutase activity, thus preventing cellular damage. At the highest Y dosage (40 µg/L), mussels reduced their biotransformation activities with no signs of cellular damage, which may be associated with the low toxicity of Y and the lower/maintenance of ETS activity. Although only minor effects were observed, the present findings raise an environmental concern for aquatic systems where anthropogenic Y concentrations are generally low but still may compromise organisms' biochemical performance. Particularly relevant are the alterations in energy metabolism and detoxification processes for their longer-term impacts on growth and reproduction but also as defense mechanisms against other stressors. Environ Toxicol Chem 2023;42:166-177. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Anthropogenic pollutants in Nephrops norvegicus (Linnaeus, 1758) from the NW Mediterranean Sea: Uptake assessment and potential impact on health.

Anthropogenic pollution is considered one of the main threats to the marine environment, and there is an imperious need to assess its potential impact on ecologically and economically relevant species. This study characterises plastic ingestion and tissue levels of potentially toxic metallic elements in Nephrops norvegicus and their simultaneous levels in abiotic compartments from three locations of the Catalan coast (NW Mediterranean Sea). A multidisciplinary assessment of the health condition of N. norvegicus through condition indices, enzymatic biomarkers and histological techniques is provided, and its relationship with anthropogenic pollutant levels explored. Plastic fibres were commonly found in stomachs of N. norvegicus (85% of the individuals), with higher abundances (13 ± 21 fibres · ind-1) in specimens captured close to Barcelona. The presence of long synthetic fibres in near-bottom waters, as well as the mirroring trends in abundance among locations for water and ingested plastics, suggest that uptake from water may be occurring potentially through suspension feeding. The spatial variability in the levels of metallic elements in N. norvegicus was poorly correlated to the variability in sediments. In any case, present levels in abdominal muscle are considered safe for human consumption. Levels of ingested plastics only showed significant, yet weak, correlations with glutathione S-transferase and catalase activities. However, no other health parameter analysed showed any trend potentially associated to anthropogenic pollutant levels. Neither the condition indices nor the histopathological assessment evidenced any signs of pathologic conditions affecting N. norvegicus. Thus, it was concluded that presently there is no evidence of a negative impact of the studied pollutants on the health condition of N. norvegicus in the studied grounds.

Do climate change related factors modify the response of Mytilus galloprovincialis to lanthanum? The case of temperature rise.

Most of the electric and electronic waste is not recycled and the release of its components into the environment is expected, including the rare-earth element Lanthanum (La), which has already been reported in the aquatic systems. Furthermore, considering climate change factors such as the predicted increase in temperature, the susceptibility of aquatic organisms to these rare elements may be modified. In light of this, the present study aimed to evaluate the relevance of temperature on La-derived effects in the mussel Mytilus galloprovincialis. Several biomarkers and La bioaccumulation were assessed in organisms exposed to 0 (control) and 10 µg/L of La at two distinct temperatures (17 and 22 °C) for 28 days. Results showed that temperature did not influence La bioaccumulation in mussels. However, exposure to La resulted in a decreased metabolic capacity and an enhancement of biotransformation enzymes activity, as a possible defense behavior of mussels to avoid La accumulation and toxicity. Nevertheless, antioxidant defenses were also inhibited leading to increased lipid peroxidation (LPO) levels. Warming alone seemed to cause a metabolic shutdown seen as reduced enzyme activities and protein carbonylation (PC) levels. Simultaneous La exposure and temperature rise caused combined effects on mussels, as they accused metabolic depression, biotransformation defenses activation, antioxidant capacity reduction, and higher cellular damage. Overall, this study highlights the need to perform environmental risk assessment studies, by considering emerging contaminants exposures at relevant concentrations, both at present and forecasted climate change scenarios.

Reduction in thermal stress of marine copepods after physiological acclimation.

We studied the phenotypic response to temperature of the marine copepod Paracartia grani at the organismal and cellular levels. First, the acute (2 days) survival, feeding and reproductive performances at 6-35°C were determined. Survival was very high up to ca. 30°C and then dropped, whereas feeding and fecundity peaked at 23-27°C. An acclimation response developed after longer exposures (7 days), resulting in a decline of the biological rate processes. As a consequence, Q10 coefficients dropped from 2.6 to 1.6, and from 2.7 to 1.7 for ingestion and egg production, respectively. Due to the similarity in feeding and egg production thermal responses, gross-growth efficiencies did not vary with temperature. Respiration rates were less sensitive (lower Q10) and showed an opposite pattern, probably influenced by starvation during the incubations. The acclimation response observed in the organismal rate processes was accompanied by changes in body stoichiometry and in the antioxidant defense and cell-repair mechanisms. Predictions of direct effects of temperature on copepod performance should consider the reduction of Q10 coefficients due to the acclimation response. Copepod population dynamic models often use high Q10 values and may overestimate thermal effects.

Micro(nano)plastics and plastic additives effects in marine annelids: A literature review.

Plastic debris are dispersed in the marine environment and are consequently available to many organisms of different trophic levels, including sediment-dwelling organisms such as polychaetae. Plastic degradation generates micro (MPs) and nanoplastics (NPs) and as well as releases bounded plastic additives, increasing the ecotoxicological risk for marine organisms. Therefore, this review summarizes current knowledge on the accumulation and effects of MPs and NPs and plastic additives in polychaetes, derived from laboratory and field evidences. Thirty-six papers (from January 2011 to September 2021) were selected and analysed: about 80% of the selected works were published since 2016, confirming the emerging role of this topic in environmental sciences. The majority of the analysed manuscripts (68%) were carried out in the laboratory under controlled conditions. These studies showed that polychaetes accumulate and are responsive to this contaminant class, displaying behavioural, physiological, biochemical and immunological alterations. The polychaetes Hediste diversicolor and Arenicola marina were the most frequent used species to study MPs, NPs and plastic additive effects. The consideration of field studies revealed that MP accumulation was dependent on the plastic type present in the sediments and on the feeding strategy of the species. Polychaetes are known to play an important role in coastal and estuarine food webs and exposure to MPs, NPs and plastic additives may impair their behavioural, physiological, biochemical and immunological responses. Thus, the estimated global increase of these contaminants in the marine environment could affect the health of these benthic organisms, with consequences at population and ecosystem levels.

Quantification of differential tissue biomarker responses to microplastic ingestion and plasticizer bioaccumulation in aquaculture reared sea bream Sparus aurata.

Marine aquaculture is considered a potential source of microplastics (MPs). MPs can induce oxidative stress and damage in marine species. In this study we evaluated the impact of MPs intake in the commercial fish, Sparus aurata, from aquaculture facilities and the antioxidant response associated to this MPs ingestion in caged specimens for 120 days. Sampling was carried out at the beginning of the study (T0), at 60 days (T60) and at 120 days (T120). At each sampling stage, gastrointestinal tract, blood, plasma, liver and muscle samples were obtained to analyse MPs intake (gastrointestinal tract), oxidative stress markers (blood, plasma and liver) and plasticizers bioaccumulation (muscle). Fish sampled at T60 presented the highest MPs intake and plasticizers accumulated in muscle over time, but with a different pattern according to type: bisphenols and phthalates. This indicates MPs ingestion induces a differential tissue response in S. aurata. Similarly, stress biomarkers presented a differential response throughout the study, depending on the analysed tissue. In the case of oxidative damage markers, for malondialdehyde (MDA) an increase throughout the study was observed both in liver and blood cells but with a progressive decrease in plasma. In the case of phase I detoxifying enzyme activities in liver, 7-ethoxyresorufin O-deethylase (EROD), 7-benzyloxy-4-[trifluoromethyl]-coumarin-O-debenzyloxylase (BFCOD) and carboxylesterases (CE), showed a comparable decrease at T60 with a slight recovery at T120. In contrast, glutathione-S-transferase (GST) activity was significantly enhanced at T60 compared to the other sampling stages. In conclusion, MPs ingestion occurs in aquaculture reared seabream where potentially associated plasticizers accumulate in the muscle and both could be responsible for plasma and liver oxidative stress damage and alterations on detoxifying biomarkers responses.

Will climate changes enhance the impacts of e-waste in aquatic systems?

The increase of the worlds' population is being accompanied by the exponential growth in waste of electrical and electronic equipment (e-waste) generation as a result of the rapid technological implementations. The inappropriate processing and disposal of this e-waste, containing rare-earth elements (REEs) such as gadolinium (Gd), may enhance its occurrence in the environment. In particular, the presence of Gd in marine systems may lead to environmental risks which are still unknown, especially considering foreseen climate modifications such as water salinity shifts due to extreme weather events. Within this context, the present study intended to assess the combined effects of Gd at variable salinities. For that, biochemical modifications were assessed in mussels, Mytilus galloprovincialis, exposed to Gd (0 and 10 µg/L) and different salinity levels (20, 30 and 40), acting individually and in combination. A decrease in salinity, induced an array of biochemical effects associated to hypotonic stress in non-contaminated and contaminated mussels, including metabolism, antioxidant and biotransformation defenses activation. Moreover, in Gd-contaminated organisms, the increase in salinity was responsible for a significant reduction of metabolic and defense mechanisms, possibly associated with a mussels' physiological response to the stress caused by the combination of both factors. In particular, Gd caused cellular damage at all salinities, but mussels adopted different strategies under each salinity to limit the extent of oxidative stress. That is, an increase in metabolism was associated to hypotonic stress and Gd exposure, an activation of defense enzymes was revealed at the control salinity (30) and a decrease in metabolism and non-activation of defenses, associated with a possible physiological defense trait, was evidenced at the highest salinity. The different strategies adopted highlight the need to investigate the risk of emerging contaminants such as REEs at present and forecasted climate change scenarios, thus providing a more realistic environmental risk assessment.

Assessment of the impact of aquaculture facilities on transplanted mussels (Mytilus galloprovincialis): Integrating plasticizers and physiological analyses as a biomonitoring strategy.

The growing plastic production and its continuous use is a significant problem. In addition, aquaculture practices have experienced a considerable growth and plastic is widely used in these activities, hence plasticizers must be considered due to their potential ecotoxicological impacts on species. Mussels placed inside an Integrated Multi-Trophic Aquaculture (IMTA) system and at two control locations were employed to quantify the ingestion of anthropogenic particles and associated chemical plasticizers, such as bisphenol A (BPA) jointly to bisphenol F (BPF) and bisphenol S (BPS), and phthalates represented by diethyl phthalate (DEP), dibutyl phthalate (DBP) and bis(2-ethylhexyl) phthalate (DEHP). In addition, some metabolism and oxidative stress related parameters were measured in mussels' whole soft tissue. Anthropogenic particle ingestion of mussels increased over time at the three locations and the following order of abundance of pollutants was observed: BPA> BPF> DEHP> DBP> BPS> DEP. Even though no differences according to location were found for pollutants' occurrence, time trends were evidenced for BPA and DEHP. On the other hand, a location effect was observed for biomarkers with highest values detected in mussels located at the vicinities of the aquaculture facility. In addition, a reduced detoxification activity was observed over time parallel to BPA decrease.

[Participation of occupational health in controlling the COVID-19 pandemic in the Valencia Autonomous Community.] / Participación de salud laboral en el control de la pandemia por COVID-19 en la Comunitat Valenciana.

In the Valencia Autonomous Community, the fight against the pandemic, in the workplace, has been articulated around joint action between the occupational health services and the Valencian public health system, promoted and coordinated by Public Health. There was experience in similar activities, but a great effort has been required in external and internal coordination, in adapting activities and information systems. Occupational risk prevention services have played an important role in the epidemiological surveillance and control of COVID-19 in companies and are also participating in vaccination. Only in the period September-December 2020, they received 67,239 cases of workers for contact studies, reported 3,059 confirmed cases and 1,206 suspected cases, determined 8,118 close work contacts and made 9,854 reports of leave due to special sensitivity. The Mutual for work-related injury and occupational disease insurance, which collaborated by vaccinating private health professionals in non-hospital centers, have declared 33,247 doses of vaccines administered.Part of the experience, the main activities carried out in the work environment, the joint work and some results are described.

En la Comunitat Valenciana la lucha contra la pandemia, en el ámbito laboral, se ha articulado alrededor de la actuación conjunta entre los servicios de salud en el trabajo y el sistema sanitario público valenciano, impulsada y coordinada desde Salud Pública. Se disponía de experiencia en actividades similares, pero ha sido necesario un gran esfuerzo de coordinación externa e interna, de adaptación de las actividades y de los sistemas de información. Los servicios de prevención de riesgos laborales han desempeñado un importante papel en la vigilancia epidemiológica y control de la COVID-19 en las empresas y además están participando en la vacunación. Solo en el periodo septiembre-diciembre de 2020 recibieron 67.239 casos de trabajadores para estudio de contactos, notificaron 3.059 casos confirmados y 1.206 casos de sospecha, determinaron 8.118 contactos laborales estrechos e hicieron 9.854 informes de baja por especial sensibilidad. Las Mutuas, que colaboraron vacunando a los profesionales de la sanidad privada de los centros no hospitalarios, han declarado 33.247 dosis de vacunas administradas. Se describe parte de la experiencia, las principales actividades realizadas en el entorno laboral, el trabajo conjunto y algunos resultados.

Salinity influences on the response of Mytilus galloprovincialis to the rare-earth element lanthanum.

The multiplicity and wide variety of applications of electrical and electronic equipment has largely increased with the technological and economic progress and, in consequence, the amount of generated waste of electrical and electronic equipment (WEEE). Due to inappropriate processing and disposal of WEEE, different chemical elements and compounds, including rare-earth elements such as Lanthanum (La) have been released in the environment. Nevertheless, the environmental risks resulting from La presence are almost unknown, especially in marine systems, which may be challenged by foreseen climate changes such as water salinity shifts. Within this context, the present study aimed to understand the combined effects of salinity and La by assessing biochemical alterations in mussels Mytilus galloprovincialis exposed to La (0 and 10 µg/L) at different salinity levels (20, 30 and 40). A decrease in salinity caused a wide range of biochemical changes to both non-contaminated and contaminated organisms, such as metabolism, antioxidant and biotransformation defenses activation, associated to hypotonic stress. Furthermore, the decrease in salinity enhanced the effects of La exposure seen as an increase on lipid and protein cellular damage in those exposed, probably due to free metal ions increase at lower salinities, resulting in a higher bioaccumulation and toxicity. In general, La exposure caused cellular damage and inhibition of antioxidant defenses in contaminated mussels when compared to non-contaminated ones, with cellular damages being higher at the lowest salinity. Overall, the present study highlights the need to investigate the presence and impacts of emerging contaminants of WEEE source at environmental relevant concentrations, not just at present but also under forecasted climate change scenarios, thus providing a more realistic environmental risk assessment.

Effects of triclosan exposure on the energy budget of Ruditapes philippinarum and R. decussatus under climate change scenarios.

We built a simulation model based on Dynamic Energy Budget theory (DEB) to assess the growth and reproductive potential of the native European clam Ruditapes decussatus and the introduced Manila clam Ruditapes philippinarum under current temperature and pH conditions in a Portuguese estuary and under those forecasted for the end of the 21st c. The climate change scenario RCP8.5 predicts temperature increase of 3 °C and a pH decrease of 0.4 units. The model was run under additional conditions of exposure to the emerging contaminant triclosan (TCS) and in the absence of this compound. The parameters of the DEB model were calibrated with the results of laboratory experiments complemented with data from the literature available for these two important commercial shellfish resources. For each species and experimental condition (eight combinations), we used data from the experiments to produce estimates for the key parameters controlling food intake flux, assimilation flux, somatic maintenance flux and energy at the initial simulation time. The results showed that the growth and reproductive potential of both species would be compromised under future climate conditions, but the effect of TCS exposure had a higher impact on the energy budget than forecasted temperature and pH variations. The egg production of R. philippinarum was projected to suffer a more marked reduction with exposure to TCS, regardless of the climatic factor, while the native R. decussatus appeared more resilient to environmental causes of stress. The results suggest a likely decrease in the rates of expansion of the introduced R. philippinarum in European waters, and negative effects on fisheries and aquaculture production of exposure to emerging contaminants (e.g., TCS) and climate change.

Ecotoxicological impact of the antihypertensive valsartan on earthworms, extracellular enzymes and soil bacterial communities.

The use of reclaimed water in agriculture represents a promising alternative to relieve pressure on freshwater supplies, especially in arid or semiarid regions facing water scarcity. However, this implies introducing micropollutants such as pharmaceutical residues into the environment. The fate and the ecotoxicological impact of valsartan, an antihypertensive drug frequently detected in wastewater effluents, were evaluated in soil-earthworm microcosms. Valsartan dissipation in the soil was concomitant with valsartan acid formation. Although both valsartan and valsartan acid accumulated in earthworms, no effect was observed on biomarkers of exposure (acetylcholinesterase, glutathione S-transferase and carboxylesterase activities). The geometric mean index of soil enzyme activity increased in the soils containing earthworms, regardless of the presence of valsartan. Therefore, earthworms increased soil carboxylesterase, dehydrogenase, alkaline phosphatase, ß-glucosidase, urease and protease activities. Although bacterial richness significantly decreased following valsartan exposure, this trend was enhanced in the presence of earthworms with a significant impact on both alpha and beta microbial diversity. The operational taxonomic units involved in these changes were related to four (Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes) of the eight most abundant phyla. Their relative abundances significantly increased in the valsartan-treated soils containing earthworms, suggesting the presence of potential valsartan degraders. The ecotoxicological effect of valsartan on microbes was strongly altered in the earthworm-added soils, hence the importance of considering synergistic effects of different soil organisms in the environmental risk assessment of pharmaceutical active compounds.

How do life-history traits influence the fate of intertidal and subtidal Mytilus galloprovincialis in a changing climate?

Coastal organisms (i.e. intertidal or upper subtidal species) live in between the terrestrial and aquatic realms, making them particularly vulnerable to climate change. In this context, intertidal organisms may suffer from the predicted sea level rise (increasing their submerged time) while subtidal organisms may suffer from anthropically-induced hypoxia and its consequences. Although there is some knowledge on how coastal organisms adapt to environmental changes, the biochemical and physiological consequences of prolonged submergence periods have not yet been well characterized. Thus, the present study aimed to assess the biochemical alterations experienced by intertidal organisms maintained always under tidal exposure (IT); intertidal organisms maintained submersed (IS); subtidal organisms maintained always submersed (SS); subtidal organisms under tidal exposure (ST). For this, Mytilus galloprovincialis specimens from contiguous intertidal and subtidal populations were exposed to the above mentioned conditions for twenty-eight days. Results indicated that both intertidal and subtidal mussels are adapted to the oxidative stress pressure caused by tidal and submerged conditions tested. Intertidal mussels did not seem to be negatively affected by submergence while ST specimens were energetically challenged by tidal exposure. Both IT and ST mussels consumed glycogen to fuel up mechanisms aiming to maintain redox homeostasis. Overall, both intertidal and subtidal populations were capable of coping with tidal exposure, although the strategies employed differed between them. These findings indicate that although IT mussels may not significantly suffer from the longer-term submergence, hypoxic events occurring in the context of global warming and other anthropogenic impacts may have consequences on both IT and ST populations. Altogether, it is important to highlight that tides may act as a confounding factor in experiments concerning coastal organisms, as it causes additional physiological and biochemical perturbations.

Biochemical aspects of susceptibility to stressors in two small cyprinids Squalius laietanus and Barbus meridionalis from the NW Mediterranean.

Specimens of two endemic cyprinids, Squalius laietanus (Catalan chub) and Barbus meridionalis (Mediterranean barbel), were sampled from a reference site in a small stream of the Ripoll River (NW Mediterranean) outside of their reproductive season. Biomarkers involved in xenobiotic-mediated responses were individually contrasted in fish of both species and 17 perfluoroalkyl substances (PFASs) analysed in muscle to reveal bioaccumulation trends. The parameters were in muscle: cholinesterases, metabolic lactate dehydrogenase (LDH) and citrate synthase (CS); and in liver: cytochrome P450 dependent activities (EROD and BFCOD), carboxylesterase (CE), glutathione S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPX) and catalase (CAT). All markers are considered adaptive defence mechanism to face stress. Sensitivity to a model pesticide: dichlorvos was also contrasted in vitro in muscular acetylcholinesterase (AChE) and hepatic CE to reveal species sensitivity to neurotoxic chemicals. Enzymatic activities related to protective mechanisms such as butyrylcholinesterase (BuChE), CE and CAT were higher in chub whereas the antioxidant defences GR and GPX were higher in barbel. Aerobic CS was also higher in barbel while anaerobic LDH was so in chub. EROD activity did not differ between the two species but BFCOD activity was higher in barbel. Levels of PFAS were higher in barbel likely due to its benthic habitat. The in vitro tests revealed higher sensitivity to dichlorvos of muscular AChE in chub (lower IC50) which was probably compensated by a higher catalytic efficiency of CE. All these former biochemical particularities are discussed in terms of fish ecological performance in front of anthropogenic stressors.