It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (�13 and �18 units, both responses), hypoxia (0.5 mg/l, mortality only) and thermal stress (+7 �C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival rates when stressed than their conspecifics from the unaffected Lada Bay. This shows that human induced habitat degradation correlates with mussel tolerance to environmental stress. We discuss possible mechanisms – e.g. the selection of tolerant genotypes or habitat-specific differences in the nutritional status of the mussels – that could explain our observation.

It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (−13 and −18 units, both responses), hypoxia (0.5mg/l, mortality only) and thermal stress (+7°C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival rates when stressed than their conspecifics from the unaffected Lada Bay. This shows that human induced habitat degradation correlates with mussel tolerance to environmental stress. We discuss possible mechanisms – e.g. the selection of tolerant genotypes or habitat-specific differences in the nutritional status of the mussels – that could explain our observation.

Fluorescence in situ hybridisation (FISH) is a powerful molecular biological tool to detect and enumerate harmful microorganism in the marine environment. Different FISH methods are available, and especially in combination with automated counting techniques, the po- tential for a routine monitoring of harmful marine micro- algae is attainable. Various oligonucleotide probes are developed for detecting harmful microalgae. However, FISH-based methods are not yet regularly included in mon- itoring programmes tracking the presence of harmful marine microalgae. A limitation factor of the FISH technique is the currently available number of suited fluorochromes attached to the FISH probes to detect various harmful species in one environmental sample at a time. However, coupled automated techniques, like flow cytometry or solid-phase cytometry, can facilitate the analysis of nu- merous field samples and help to overcome this draw- back. A great benefit of FISH in contrast to other molecular biological detection methods for harmful ma- rine microalgae is the direct visualisation of the hybridised target cells, which are not permitted in cell free formats, like DNA depending analysis methods. Therefore, an additional validation of the FISH-generated results is simultaneously given.

Fluorescence in situ hybridisation (FISH) is a powerful molecular biological tool to detect and enumerate harmful microorganism in the marine environment. Different FISH methods are available, and especially in combination with automated counting techniques, the potential for a routine monitoring of harmful marine microalgae is attainable. Various oligonucleotide probes are developed for detecting harmful microalgae. However, FISH-based methods are not yet regularly included in monitoring programmes tracking the presence of harmful marine microalgae. A limitation factor of the FISH technique is the currently available number of suited fluorochromes attached to the FISH probes to detect various harmful species in one environmental sample at a time. However, coupled automated techniques, like flow cytometry or solid-phase cytometry, can facilitate the analysis of numerous field samples and help to overcome this drawback. A great benefit of FISH in contrast to other molecular biological detection methods for harmful marine microalgae is the direct visualisation of the hybridised target cells, which are not permitted in cell free formats, like DNA depending analysis methods. Therefore, an additional validation of the FISH-generated results is simultaneously given.

The dumping of dredged sediments represents a major stressor for coastal ecosystems. The impact on the ecosystem function is determined by its complexity not easy to assess. In the present study, we evaluated the potential of bacterial community analyses to act as ecological indicators in environmental monitoring programmes. We investigated the functional structure of bacterial communities, applying functional gene arrays (GeoChip 4.2). The relationship between functional genes and environmental factors was analysed using distance-based multivariate multiple regression. Apparently, both the function and structure of the bacterial communities are impacted by dumping activities. The bacterial community at the dumping centre displayed a significant reduction of its entire functional diversity compared with that found at a reference site. DDX compounds separated bacterial communities of the dumping site from those of un-impacted sites. Thus, bacterial community analyses show great potential as ecological indicators in environmental monitoring.

The dumping of dredged sediments represents a major stressor for coastal ecosystems. The impact on the ecosystem function is determined by its complexity not easy to assess. In the present study, we evaluated the potential of bacterial community analyses to act as ecological indicators in environmental monitoring programmes. We investigated the functional structure of bacterial communities, applying functional gene arrays (GeoChip4.2). The relationship between functional genes and environmental factors was analysed using distance-based multivariate multiple regression. Apparently, both the function and structure of the bacterial communities are impacted by dumping activities. The bacterial community at the dumping centre displayed a significant reduction of its entire functional diversity compared with that found at a reference site. DDX compounds separated bacterial communities of the dumping site from those of un-impacted sites. Thus, bacterial community analyses show great potential as ecological indicators in environmental monitoring.

In recent decades, many toxicological tests based on in vivo or in vitro models, mainly from mammalian (rat-mouse) and fish species, were used to assess the risks raised by contact or ingestion of molecules of pharmaceutical, agricultural, or natural origin. But no, or few, in vitro tests using other non-mammalian models such as bird have been explored despite their advantages: the embryonic gonads of birds have a high plasticity of development sensitive to estrogen, and sperm production is nearly two times faster than in rodents. Hence, we have established an in vitro culture of germ cells and somatic cells from chicken post-natal testis, and we have evaluated the sensitivity against the endocrine disruptor compound mono-(2-ethylhexyl) phthalate (MEHP) in comparison to previous studies using rodent and human models. After 96 h of exposure in presence of 10 μM MEHP, chicken seminiferous tubules cultures present a structural alteration, a reduction in cell proliferation and in germ cells population. Apoptosis of germ and somatic cells increases in presence of 1 μM MEHP. Furthermore, MEHP does not affect inhibin B and lactate production by Sertoli cells. These results are in accordance with previous studies using rat, mice, or human culture of testicular cells and in similar range of exposures or even better sensitivity for some "end-points" (biological parameters). In conclusion, the establishment of this postnatal testicular cells culture could be considered as an alternative method to in vivo experiments frequently used for evaluating the impact on the terrestrial wildlife species. This method could be also complementary to mammal model due to the limiting number of animals used and its elevated sensitivity.

In recent decades, many toxicological tests based on in vivo or in vitro models, mainly from mammalian (rat–mouse) and fish species, were used to assess the risks raised by contact or ingestion of molecules of pharmaceutical, agricultural, or natural origin. But no, or few, in vitro tests using other non-mammalian models such as bird have been explored despite their advantages: the embryonic gonads of birds have a high plasticity of development sensitive to estrogen, and sperm production is nearly two times faster than in rodents. Hence, we have established an in vitro culture of germ cells and somatic cells from chicken post-natal testis, and we have evaluated the sensitivity against the endocrine disruptor compound mono-(2-ethylhexyl) phthalate (MEHP) in comparison to previous studies using rodent and human models. After 96 h of exposure in presence of 10 μM MEHP, chicken seminiferous tubules cultures present a structural alteration, a reduction in cell proliferation and in germ cells population. Apoptosis of germ and somatic cells increases in presence of 1 μM MEHP. Furthermore, MEHP does not affect inhibin B and lactate production by Sertoli cells. These results are in accordance with previous studies using rat, mice, or human culture of testicular cells and in similar range of exposures or even better sensitivity for some “end-points” (biological parameters). In conclusion, the establishment of this postnatal testicular cells culture could be considered as an alternative method to in vivo experiments frequently used for evaluating the impact on the terrestrial wildlife species. This method could be also complementary to mammal model due to the limiting number of animals used and its elevated sensitivity.

The triazole fungicide epoxiconazole is extensively used to control fungi on crops and may present some potential risk from runoff on coastal ecosystems located close to agricultural areas. Phytotoxicity assessments were conducted on the marine diatom Chaetoceros calcitrans using both the active ingredient and its formulated product (Opus). The 3-day EC50 using cell count was 2.31 mg/L for epoxiconazole active ingredient and 2.9 mu g/L for epoxiconazole-formulated. The fungicide produced an increase of cellular volume, pigment (chlorophylls a, c, and carotenoids) content, ATP synthesis, and rates of photosynthesis and respiration. Progressive algal cell recovery from epoxiconazole effects occurred after 3 days, with the increasing cell density. Differences in cell age, light, and nutrient composition induced changes in epoxiconazole sensitivity. Since these parameters affect cellular division rates, the cellular density is an important parameter in toxicity tests.

The triazole fungicide epoxiconazole is extensively used to control fungi on crops and may present some potential risk from runoff on coastal ecosystems located close to agricultural areas. Phytotoxicity assessments were conducted on the marine diatom Chaetoceros calcitrans using both the active ingredient and its formulated product (Opus). The 3-day EC₅₀ using cell count was 2.31 mg/L for epoxiconazole active ingredient and 2.9 μg/L for epoxiconazole-formulated. The fungicide produced an increase of cellular volume, pigment (chlorophylls a, c, and carotenoids) content, ATP synthesis, and rates of photosynthesis and respiration. Progressive algal cell recovery from epoxiconazole effects occurred after 3 days, with the increasing cell density. Differences in cell age, light, and nutrient composition induced changes in epoxiconazole sensitivity. Since these parameters affect cellular division rates, the cellular density is an important parameter in toxicity tests.

This study aimed to compare the contamination levels of various organohalogenated compounds in two migratory fish species in the Vilaine River in western France. Organochlorinated pesticides, polychlorinated biphenyls (PCBs), dioxins (polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs)), and polybrominated diphenyl ethers (PBDEs) were analyzed in two diadromous species from the Vilaine estuary, the grey mullet (Liza ramada)-an amphihaline species, and the allis shad (Alosa alosa)-an anadromous species. Fish were collected in spring 2004 and spring 2005, upstream and downstream of the Arzal Dam. PCB contamination varied from 27 to 200 ng g(-1) dry weight (d.w.). PCDDs/Fs, expressed in toxicity equivalent quantity (TEQ) varied from 0.4 to 2.8 pg g(-1) d.w. Dioxins and dioxin-like PCBs expressed in total TEQ varied from 1.4 to 18.8 pg g(-1) d.w. PBDE47 was present at around 2-10 ng g(-1) d.w. and concentrations of the insecticide dichlorodiphenyltrichloroethane breakdown product p,p'-dichlorodiphenylchloroethylene varied from 1 to 14 ng g(-1) d.w. For both species, specimens collected upstream were more contaminated. The grey mullet specimens were less contaminated than the allis shad when taken downstream of the dam but were more contaminated upstream. The allis shads presented intermediate contaminant concentrations with a less pronounced difference between upstream and downstream specimens. However, it is thought that shads do not feed when they spawn in the upstream parts of rivers, which should modify the contaminant concentrations. However, measurements in upstream shad samples show an unexpected increase of the contamination, which remains unexplained.

This study aimed to compare the contamination levels of various organohalogenated compounds in two migratory fish species in the Vilaine River in western France. Organochlorinated pesticides, polychlorinated biphenyls (PCBs), dioxins (polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs)), and polybrominated diphenyl ethers (PBDEs) were analyzed in two diadromous species from the Vilaine estuary, the grey mullet (Liza ramada)—an amphihaline species, and the allis shad (Alosa alosa)—an anadromous species. Fish were collected in spring 2004 and spring 2005, upstream and downstream of the Arzal Dam. PCB contamination varied from 27 to 200 ng g⁻¹ dry weight (d.w.). PCDDs/Fs, expressed in toxicity equivalent quantity (TEQ) varied from 0.4 to 2.8 pg g⁻¹ d.w. Dioxins and dioxin-like PCBs expressed in total TEQ varied from 1.4 to 18.8 pg g⁻¹ d.w. PBDE47 was present at around 2–10 ng g⁻¹ d.w. and concentrations of the insecticide dichlorodiphenyltrichloroethane breakdown product p,p′-dichlorodiphenylchloroethylene varied from 1 to 14 ng g⁻¹ d.w. For both species, specimens collected upstream were more contaminated. The grey mullet specimens were less contaminated than the allis shad when taken downstream of the dam but were more contaminated upstream. The allis shads presented intermediate contaminant concentrations with a less pronounced difference between upstream and downstream specimens. However, it is thought that shads do not feed when they spawn in the upstream parts of rivers, which should modify the contaminant concentrations. However, measurements in upstream shad samples show an unexpected increase of the contamination, which remains unexplained.

Multi-biomarker approaches are used to assess ecosystem health and identify impacts of environmental stress on organisms. However, exploration of large datasets by environmental managers represents a major challenge for regulatory application of this tool. Several integrative tools were developed to summarize biomarker responses. The aim of the present paper is to update calculation of the "Integrated Biological Response" (IBR) described by Beliaeff and Burgeot (Environ Toxicol Chem 21:1316-1322, 2002) to avoid weaknesses of this integrative tool. In the present paper, a novel index named "Integrated Biological Responses version 2" based on the reference deviation concept is presented. It allows a clear discrimination of sampling sites as for the IBR, but several differences are observed for contaminated sites according to up- and downregulation of biomarker responses. This novel tool could be used to integrate multi-biomarker responses not only in large-scale monitoring but also in upstream/downstream investigations.

Multi-biomarker approaches are used to assess ecosystem health and identify impacts of environmental stress on organisms. However, exploration of large datasets by environmental managers represents a major challenge for regulatory application of this tool. Several integrative tools were developed to summarize biomarker responses. The aim of the present paper is to update calculation of the “Integrated Biological Response” (IBR) described by Beliaeff and Burgeot (Environ Toxicol Chem 21:1316–1322, 2002) to avoid weaknesses of this integrative tool. In the present paper, a novel index named “Integrated Biological Responses version 2” based on the reference deviation concept is presented. It allows a clear discrimination of sampling sites as for the IBR, but several differences are observed for contaminated sites according to up- and downregulation of biomarker responses. This novel tool could be used to integrate multi-biomarker responses not only in large-scale monitoring but also in upstream/downstream investigations.