Some planktonic groups suffer negative effects from ocean acidification (OA), although copepods might be less sensitive. We investigated the effect of predicted CO2 levels (range 480-750 ppm), on egg production and hatching success of two copepod species, Centropages typicus and Temora longicornis. In these short-term incubations there was no significant effect of high CO2 on these parameters. Additionally a very high CO2 treatment, (CO2 = 9830 ppm), representative of carbon capture and storage scenarios, resulted in a reduction of egg production rate and hatching success of C. typicus, but not T. longicornis. In conclusion, reproduction of C. typicus was more sensitive to acute elevated seawater CO2 than that of T. longicornis, but neither species was affected by exposure to CO2 levels predicted for the year 2100. The duration and seasonal timing of exposures to high pCO2, however, might have a significant effect on the reproduction success of calanoid copepods.

In southern Sri Lanka, irrigation influences the concentrations of faecal bacteria and inorganic toxic contaminants in groundwater. We develop a groundwater vulnerability map describing the potential human health implications of harmful constituents in the Uda Walawe Basin, by overlaying geological and land use data with information describing the irrigation system, the oxygen isotope composition of water bodies, and the concentrations of selected contaminants. Given the limited data available, we examine the spatial distribution of harmful constituents and the potential human health risks. Fluoride poisoning from groundwater is the greatest health threat in our study area, where fluoride concentrations ranging from 0.1 to 9.2 mg/L are associated with a geologic origin. Arsenic occurs in high concentrations, up to 0.4 mg/L, in areas with low recharge, although the source of arsenic is not clear. Nitrate concentrations are low, ranging from 0.4 to 23 mg/L, despite high fertilizer inputs, except in areas with low recharge and non-favourable reducing conditions, where concentrations up to 136 mg/L are found. Faecal bacteria decrease from surface water via shallow groundwater to deep groundwater. Irrigation water appears to play a major role in increasing microbial contamination and diluting inorganic constituents in groundwater. Hence, the most important determinants for mapping groundwater vulnerability are local geology and infiltration of irrigation water. The method we present provides a qualitative, yet practical, alternative to commonly used vulnerability mapping techniques for countries where high human health risk via consumption of groundwater is inevitable, and thus acts as a tool for selecting preventive and curative measures.

The hatching process of the Pacific abalone Haliotis discus hannai was prolonged at a pH of 7.6 and pH 7.3, and the embryonic developmental success was reduced. The hatching rate at pH 7.3 was significantly (10.8%) lower than that of the control (pH 8.2). The malformation rates at pH 7.9 and pH 8.2 were less than 20% but were 53.8% and 77.3% at pH 7.6 and pH 7.3, respectively. When newly hatched larvae were incubated for 48 h at pH 7.3, only 2.7% of the larvae settled, while more than 70% of the larvae completed settlement in the other three pH treatments. However, most 24 h old larvae could complete metamorphosis in all four pH treatments. Overall, a 0.3-unit reduction in water pH will produce no negative effect on the early development of the Pacific abalone, but further reduction in pH to the values predicted for seawater by the end of this century will have strong detrimental effects.

The bacteriological and physicochemical characteristics of water and sediment collected in four fisheries situated in the north of Cameroon were evaluated. In these locations, all the analysed parameters (temperature, pH, salinity, conductivity, turbidity, suspended matter, organic matter, phosphates, sulphates, nitrates, chloride, calcium, magnesium, iron and nitrogen) were the highest, except for chlorides. Total mesophile aerobic flora varied between 1.4±0.50×105 in Tibati and 5.57±0.50×106 CFU/mL in Lagdo. Salmonella concentration was comprised between 66.66±1.62 in Tibati and 274±3.16 CFU/mL in Yagoua. There was about 10±0.50 CFU/mL Vibrio in Lagdo and 342.27±5.53 CFU/mL in Maga. Staphylococcus concentration was between 1.4±0.55×103 CFU/mL in Tibati and 4.44±0.9×104 in Maga. Clostridia were comprised between 0.33±0.00 in Tibati and 226.66±4.29 CFU/mL in Maga while Pseudomonas concentration was comprise between 16.26±0.70 in Tibati and 326.66±6.00 CFU/mL in Lagdo. Faecal Streptococcus varied between 0.33±0.00 in Tibati and 238.66±8.15 CFU/mL in Yagoua. The total mesophile aerobic flora was significantly high (P<0,005) in Lagdo while Clostridium, faecal streptococcus, and Streptococcus concentration were significantly high in Maga, Yagoua and Lagdo. Lake's sediments in Maga were the most infected. The different analysis revealed that the fisheries were relatively polluted. Some of the bacteria counted like Pseudomonas and Vibrio might be pathogenic for fishes. (Résumé d'auteur)

The impacts of ocean acidification on coastal biofilms are poorly understood. Carbon dioxide vent areas provide an opportunity to make predictions about the impacts of ocean acidification. We compared biofilms that colonised glass slides in areas exposed to ambient and elevated levels of pCO2 along a coastal pH gradient, with biofilms grown at ambient and reduced light levels. Biofilm production was highest under ambient light levels, but under both light regimes biofilm production was enhanced in seawater with high pCO2. Uronic acids are a component of biofilms and increased significantly with high pCO2. Bacteria and Eukarya denaturing gradient gel electrophoresis profile analysis showed clear differences in the structures of ambient and reduced light biofilm communities, and biofilms grown at high pCO2 compared with ambient conditions. This study characterises biofilm response to natural seabed CO2 seeps and provides a baseline understanding of how coastal ecosystems may respond to increased pCO2 levels.

The objective was to describe and model varia- tion patterns in individual fish responses to contaminants among estuaries, season and gender. Two hundred twenty- seven adult European flounders were collected in two sea- sons (winter and summer) in four estuaries along the Bay of Biscay (South West France), focusing on a pristine system (the Ster), vs. three estuaries displaying contrasted levels of contaminants (the Vilaine, Loire and Gironde). Twenty-three variables were measured by fish, considering the load of contaminants (liver metals, liver and muscle persistent organic pollutants, muscle polycyclic aromatic hydrocar- bons); the gene expression (Cyt C oxydase, ATPase, BHMT, Cyt P450 1A1, ferritin); the blood genotoxicity (Comet test); and liver histology (foci of cellular alteration–tumour, steatosis, inflammation, abnormal glycogen storage). Ca- nonical redundancy analysis (RDA) was used to model these variables using gender, season and estuary of origin as explanatory variables. The results underlined the homo- geneity of fish responses within the pristine site (Ster) and more important seasonal variability within the three contam- inated systems. The complete model RDA was significant and explained 35 % of total variance. Estuary and season respectively explained 30 and 5 % of the total independent variation components, whilst gender was not a significant factor. The first axis of the RDA explains nearly 27 % of the total variance and mostly represents a gradient of contami- nation. The links between the load of contaminants, the expression of several genes and the biomarkers were ana- lysed considering different levels of chemical stress and a possible multi-stress, particularly in the Vilaine estuary.

A mesocosm experiment was conducted to quantify the relationships between the presence and body size of two burrowing heart urchins (Brissopsis lyrifera and Echinocardium cordatum) and rates of sediment nutrient flux. Furthermore, the impact of seawater acidification on these relationships was determined during this 40-day exposure experiment. Using carbon dioxide (CO2) gas, seawater was acidified to pHNBS 7.6, 7.2 or 6.8. Control treatments were maintained in natural seawater (pH = 8.0). Under normocapnic conditions, burrowing urchins were seen to reduce the sediment uptake of nitrite or nitrate whilst enhancing the release of silicate and phosphate. In acidified (hypercapnic) treatments, the biological control of biogeochemical cycles by urchins was significantly affected, probably through the combined impacts of high CO2 on nitrifying bacteria, benthic algae and urchin behaviour. This study highlights the importance of considering biological interactions when predicting the consequences of seawater acidification on ecosystem function.

Extensive CO2 vents have been discovered in the Wagner Basin, northern Gulf of California, where they create large areas with lowered seawater pH. Such areas are suitable for investigations of long-term biological effects of ocean acidification and effects of CO2 leakage from subsea carbon capture storage. Here, we show responses of benthic foraminifera to seawater pH gradients at 74-207 m water depth. Living (rose Bengal stained) benthic foraminifera included Nonionella basispinata, Epistominella bradyana and Bulimina marginata. Studies on foraminifera at CO2 vents in the Mediterranean and off Papua New Guinea have shown dramatic long-term effects of acidified seawater. We found living calcareous benthic foraminifera in low pH conditions in the northern Gulf of California, although there was an impoverished species assemblage and evidence of post-mortem test dissolution.

The human diet is recognised as one possible major exposure route to the overall perfluorinated alkylated substances (PFAS) burden of the human population, resulting directly from contamination of dietary food items, as well as migration of PFAS from food packaging or cookware. Most European countries carry out national monitoring programs (food basket studies) to monitor contamination with pollutants. Usually, for PFASs, non-coordinated approaches are used in Europe, since food basket studies are mainly carried out by national authorities following national requirements and questions, making comparisons between different countries difficult. A harmonised sampling campaign collecting similar food items in a uniform procedure enabling direct comparison between different regions in Europe was designed. We selected four countries (Belgium, Czech Republic, Italy and Norway), representing the four regions of Europe: West, East, South and North. In spring 2010 and 2011, 20 different types of vegetables were sampled in Belgium, Czech Republic, Italy and Norway. Perfluorinated carboxylic acids (PFCAs) were the main group of detected PFASs, with perfluorinated octanoic acid (PFOA) as the most abundant PFCA (with exception of samples from Czech Republic), followed by perfluorinated hexanoic acid and perfluorinated nonanoic acid. Dietary intake estimates for PFOA show only low human exposure due to vegetable consumption for adults and children, mostly governed by high intake of potatoes.

Nous développons un modèle à générations emboîtées dans lequel l’évolution de la pollutionet la formation de la préoccupation environnementale sont endogènes. D’un côté, despersonnes concernées de façon hétérogène par les questions environnementales participentvolontairement à la dépollution. D’un autre côté, la transmission des attitudes vis-à-vis del’environnement résulte d’un choix économique qui dépend lui-même de la pollution. Lemodèle prédit que la proportion à long terme d’individus préoccupés par l’environnement seraforte dans tous les cas. Cependant, selon la nature de la technologie qui génère la pollution, latransition d’une société peu préoccupée par l’environnement vers une société fortementpréoccupée par l’environnement s’accompagne de deux effets différents sur le niveau depollution à long terme. Si la technologie est « propre », on aboutit à un niveau d’équilibrestable de pollution. A l’inverse, si elle est « sale », la pollution connaît une croissanceillimitée qui finit par causer un désastre environnemental. Ce résultat reproduit les faitsstylisés observés quant à l’évolution conjointe de la préoccupation environnementale et lapollution dans les pays en développement. Dans le deuxième cas, nous montrons que destransferts intergénérationnels de la génération âgée vers la génération active jeune rétablissentla possibilité d’atteindre un état stationnaire de pollution. | We develop an overlapping generations model within which the evolution of pollution and theformation of environmental concern are endogenous. On the one hand, peopleheterogeneously concerned with environmental issues contribute to pollution which is apublic bad. On the other hand, the transmission of environmental attitudes is the result ofsome economic choice which is affected by pollution. The model predicts that the long runproportion of environmentally concerned individuals will always be high. Though, dependingon the pollution-generating technology, the transition from a low-environmentally concernedsociety to a high-environmentally concerned one is accompanied by two different outcomesregarding the long run level of pollution. If the technology is “clean”, there is a stable steadystate level of pollution. However, if it is “dirty”, pollution experiences an unlimited growthwhich eventually causes an environmental disaster. This result captures some stylized factsregarding the joint evolution of environmental concern and pollution in developing nations. Inthe latter case, we show that intergenerational transfers from the older generation to the youngworking one restore the possibility to reach a stationary level of pollution.