peer reviewed | Persistent Organic Pollutants (POPs) are still globally distributed and can exert different effects on ecosystems. Little is known about the occurrence of these contaminants in terrestrial birds from South America. In this study, POPs were assessed for the first time in a flightless herbivorous species from the Pampas grasslands, the Greater rhea (Rhea americana). Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), were determined in 18 samples of feathers from free-ranging and captive individuals inhabiting four sites with different land use in central Argentina. Among the 16 POPs tested in those feathers, 6 PCBs (28, 52, 101, 138, 153 and 180) and 8 OCPs (α-HCH, β-HCH, γ-HCH, p,p'-DDE, p,p'-DDD, o,p'-DDT, p,p'-DDT and HCB) were quantified. No PBDEs were detected. Total concentration of POPs was higher in populations living in an intensive crop production area (Agriculture: 159 ng.g-1 and Farm: 97.53 ng.g-1) compared to the population in an urban area (Zoo: 45.86 ng/g) and an agroecosystem with extensive rearing of livestock (Cattle rearing: 36.77 ng.g-1). PCBs were the most abundant pollutants in all the populations studied. Lower chlorinated CB 52 and CB 101 were the principal PCB congeners detected, representing at least 70% of the total quantified. All populations studied showed a DDE + DDD / DDT ratio > 1, indicating a historical application of this insecticide. This study provides a new contribution to the scarce data on POP concentrations in South American bird species. Further investigations are needed to evaluate their potential effects on the health individuals and populations.

peer reviewed | Noise pollution is an anthropogenic stressor that is increasingly recognized for its negative impact on the physiology, behavior and fitness of marine organisms. Driven by the recent expansion of maritime shipping, artisanal fishing and tourism (e.g., motorboats used for recreational purpose), underwater noise increased greatly on coral reefs. In this review, we first provide an overview on how reef organisms sense and use sound. Thereafter we review the current knowledge on how underwater noise affects different reef organisms. Although the majority of available examples are limited to few fish species, we emphasize how the impact of noise differs based on an organisms’ acoustic sensitivity, mobility and developmental stage, as well as between noise type, source and duration. Finally, we highlight measures available to governments, the shipping industry and individual users and provide directions for polices and research aimed to manage this global issue of noise emission on coral reefs.

Microplastics (MP) are defined as synthetic organic pollutants sized <5 mm and have been recorded in various environments worldwide. Due to their small size, they pose a potential risk for many organisms throughout the food web. However, little is known about MP distribution patterns and associated transport mechanisms. Rivers may act as pathways for MP into marine environments. In this study, we investigate the occurrence of MP in the estuary and lower stretch of the second-largest German River, the Weser, representative of a significant interface between fresh water and marine environments. The aim of the study was to enhance the general understanding by providing novel, comprehensive data and suggestions for future studies on estuarine systems. Surface water samples of two different size classes were collected by ship using an on-board filtration system (11-500 µm fraction) and net sampling (500-5000 µm fraction). After a thorough sample preparation, all samples were analysed with Focal Plane Array (FPA) Fourier Transform Infrared (FTIR) spectroscopy and Attenuated Total Reflection (ATR) FTIR spectroscopy in order to obtain information on MP concentrations, polymer composition and size distribution. Our findings show highest concentrations in the 11-500 µm fraction (2.3 × 101 − 9.7 × 103 m−3), with the polymer cluster acrylates/polyurethanes/varnish being dominant. The >500 µm fraction was dominated by polyethylene. Estimated MP concentrations generally increased in the Turbidity Maximum Zone (TMZ) and decreased towards the open sea. This study contributes to the current research by providing novel insights into the MP pollution of the estuary and lower stretch of an important European river and provides implications for future MP monitoring measures.

The wellbeing of marine organisms is connected to their microbiome. Oysters are a vital food source and provide ecological services, yet little is known about how climate change such as ocean acidification and warming will affect their microbiome. We exposed the Sydney rock oyster, Saccostrea glomerata, to orthogonal combinations of temperature (24, 28 degrees C) and pCO(2) (400 and 1000 mu atm) for eight weeks and used amplicon sequencing of the 16S rRNA (V3-V4) gene to characterise the bacterial community in haemolymph. Overall, elevated pCO(2) and temperature interacted to alter the microbiome of oysters, with a clear partitioning of treatments in CAP ordinations. Elevated pCO(2) was the strongest driver of species diversity and richness and elevated temperature also increased species richness. Climate change, both ocean acidification and warming, will alter the microbiome of S. glomerata which may increase the susceptibility of oysters to disease.

Recreational fishers often consume their catch, which may expose them to environmental contaminants. However, targeted risk assessment for exceeding the tolerable weekly intake (TWI) of a specific contaminant is often lacking, as specific data on the extent of fishing, consumption rates, and contamination of the caught seafood is needed. This study examined recreational fishing for nephrops (Nephrops norvegicus) at several different locations in Western Norway to identify important risk factors. The combination of a field survey to examine actual catches, interviews of recreational fishers about their seafood eating habits, and the analysis of total mercury (Hg, as a proxy for methylmercury (MeHg)) in recreationally captured nephrops allowed to conduct a targeted risk assessment. Recreational fishers consumed on average seven nephrops per meal, and 73% of the fishers ate nephrops once a month or more. The average Hg concentrations in nephrops were below the legal maximum level (100 ± 50 μg/kg wet weight (mean ± SD)). Hg concentrations in female nephrops were significantly higher than in males at the same size, and differed significantly between locations. The recreational fishers in this study were not at risk of exceeding the TWI for MeHg from consuming nephrops only; however, there is a general risk of exceeding TWI for MeHg as 70% of the fishers reported a frequent consumption of fish for dinner. Targeted risk assessments on recreational fishers may reveal particularly vulnerable populations where national dietary surveys may miss the highest seafood consumers. | publishedVersion

Embargo until November 4 2023 | Microplastic presence in benthic marine systems is a widely discussed topic. The influence of the natural matrix on microplastic distribution within the sedimentary matrix is often overlooked. Marine sediments from the western inner Oslofjord, Norway, were investigated for temporal trends, with a particular focus on the relationship between sediment grain-sizes and microplastic distribution. Density separation, optical microscopy and chemical validation were used to categorize microplastics. Microplastic concentrations ranged from 0.02 to 1.71 MPs g −1 dry weight (dw). Fibres were the most common (76%), followed by fragments and films (18%, 6%). Common polymers were polyesters (50%), polypropylene (18%), polymethylmethacrylate (9%), rayon and viscose (5%) and elastane (4%). Microplastics appear to accumulate preferentially according to their morphology and polymer type in certain sediment grain-sizes. Microplastics inputs to the Oslofjord appear to derive from a wastewater treatment plant in the vicinity. Although, the redistribution of microplastics within the fjord needs further investigation. | acceptedVersion

PR | IFPRI3; ISI; DCA; 1 Fostering Climate-Resilient and Sustainable Food Supply; 2 Promoting Healthy Diets and Nutrition for all; G Cross-cutting gender theme | DSGD

peer reviewed | Cadmium (Cd) is considered one of the heavy metals disturbing plant biophysiological functions. The potential role of phosphorus (P) nutrition in the attenuation of Cd effects on photosynthetic efficiency, plant growth, and cadmium uptake has been investigated in hydroponically grown tomato. Two P nutrition regimes (P15: 15 mg l-1; P30: 30 mg l-1) were assessed in the presence or absence of Cd (Cd0: 0 μM; Cd25: 25 μM of CdCl2). The results showed a positive effect of P30 concentration on leaf chlorophyll content and chlorophyll a fluorescence compared to P15 treatment under Cd stress (Cd25). The disturbance of electron transfer caused by Cd at K and I-steps of OJIP transient was attenuated with sufficient P supply. P30 enhanced the performance index of photosystem II and the efficiency of electron transfer to electron acceptor at PSI acceptor side. Besides, increased P concentration improved root growth parameters and biomass accumulation in the presence of Cd. It was found that root tissues accumulated more Cd than shoots and Cd translocation was reduced with increasing P concentration. Our results reveal that Cd-P interaction induced a cascade of physiological and chemical changes in plants. An optimal P nutrition can attenuate Cd stress on plant by the promotion of nitrogen and potassium uptake, which in return improved photosynthesis efficiency, enhanced biomass accumulation and distribution, and minimized Cd accumulation and translocation in plant tissues. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG part of Springer Nature.

International audience | Epidemiological indications connect maternal and developmental presence or exposure to pesticides with an increased risk for a spectrum of neurological trajectories. To provide pre-clinical data in support of this hypothesis, we used two distinct experimental models. First, female and male mice were fed immediately prior to mating, and the resulting pregnant dams were continously fed during gestation and lactation periods using chow pellets containing a cocktail of six pesticides at tolerable daily intake levels. Male and female offspring were then tracked for behavioral and in vivo electrophysiological adaptations. Second, a zebrafish model allowed us to screen toxicity and motor-behavior outcomes specifically associated with the developmental exposure to a low-to-high concentration range of the cocktail and of each individual pesticide. Here, we report anxiety-like behavior in aging male mice maternally exposed to the cocktail, as compared to age and gender matched sham animals. In parallel, in vivo electrocorticography revealed a decrease in gamma (40-80 Hz) and an increase of theta (6-9 Hz) waves, delineating a long-term, age-dependent, neuronal slowing. Neurological changes were not accompanied by brain structural malformations. Next, by using zebrafish larvae, we showed an increase of all motor-behavioral parameters resulting from the developmental exposure to 10 μg/L of pesticide cocktail, an outcome that was not associated with midbrain structural or neurovascular modifications as assessed by in vivo 2-photon microscopy. When screening each pesticide, chlorpyrifos elicited modifications of swimming parameters at 0.1 μg/L, while other components provoked changes from 0.5 μg/L. Ziram was the single most toxic component inducing developmental malformations and mortality at 10 μg/L. Although we have employed non-equivalent modalities and timing of exposure in two dissimilar experimental models, these outcomes indicate that presence of a pesticide cocktail during perinatal periods represents an element promoting behavioral and neurophysiological modifications. The study limitations and the possible pertinence of our findings to ecotoxicology and public health are critically discussed.