Perspectives from the French workshop on the development and validation of biomarkers and bioassays for the monitoring of aquatic environments

International audienceDuring the past three decades, there has been an increasing interest in the field of ecotoxicology for development of effect-based monitoring tools (EBMTs) including in vitro tests, biomarkers and whole organism bioassays. This interest is due to the practical application of EBMTs in the surveillance of the quality of water and aquatic ecosystems (ICES, 2008). Within this framework, these ecotoxicological tools seem to offer numerous potential advantages, as they allow one to take into account the cumulative impact of the whole contaminants present in the field, and the bio-available and active fractions of toxicants as well as their degradation bioaccumulation, biotransformation (Lam and Gray, 2003; Hecker and Hollert, 2009). Hence, they are often seen as complementary tools to conventional environmental monitoring approaches, mostly based on the measurement of a predefined list of chemical substances in various aquatic compartments (water, sediments and biota) and the analyses of indices of biological integrity (OSPAR 2004). Due to these research activities, several core EBMTs (SGIMC, 2011) are now well characterised and may be directly used to assess the quality of the aquatic environment under a European consensus (Table 1; Sanchez and Porcher, 2009; Lyons et al., 2010). However, if EBMTs are widely used in research studies and provide, at geographically and temporally limited scales, data on ecotoxicological status of water bodies, few applications of EBMTs are currently implemented in regulatory environmental monitoring programs

Guidelines for the integrated monitoring and assessment of contaminants and their effects

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DNA adducts in fish following an oil spill exposure

On 12 December 1999, one third of the load of the Erika tanker, amounting to about 10,000 t crude oil flowed into sea waters close to the French Atlantic Coast. This oil contained polycyclic aromatic compounds (PAC) that are known to be genotoxic. Genotoxic effects induce DNA adducts formation, which can thus be used as pollution biomarkers. Here, we assessed the genotoxic impact of the “Erika” oil spill by DNA adducts detection in the liver of immature fishes (Solea solea) from four locations of the French Brittany coasts. Two months after the spill, a high amount of DNA adducts was found in samples from all locations, amounting to 92–290 DNA adduct per 109 nucleotides. Then total DNA adduct levels decreased to reach about 50 adducts per 109 nucleotides nine months after the spill. In vitro experiments using human cell cultures and fish liver microsomes evidence the genotoxicity of the Erika fuel. They also prove the formation of reactive species able to create DNA adducts. Furthermore, in vitro and in vivo DNA adducts fingerprints are similar, thus confirming that DNA adducts are a result of the oil spill

Profile of micronucleus frequencies and DNA damage in different species of fish in a eutrophic tropical lake

Lake Paranoá is a tropical reservoir for the City of Brasilia, which became eutrophic due to inadequate sewage treatment associated with intensive population growth. At present, two wastewater treatment plants are capable of processing up to 95% of the domestic sewage, thereby successfully reducing eutrophization. We evaluated both genotoxic and cytotoxic parameters in several fish species (Geophagus brasiliensis, Cichla temensis, Hoplias malabaricus, Astyanax bimaculatus lacustres, Oreochromis niloticus, Cyprinus carpio and Steindachnerina insculpita) by using the micronucleus (MN) test, the comet assay and nuclear abnormality assessment in peripheral erythrocytes. The highest frequencies of MN were found in Cichla temensis and Hoplias malabaricus, which were statistically significant when compared to the other species. However, Steindachnerina insculpita (a detritivorous and lake-floor feeder species) showed the highest index of DNA damage in the comet assay, followed by C. temensis (piscivorous). Nuclear abnormalities, such as binucleated, blebbed, lobed and notched cells, were used as evidence of cytotoxicity. Oreochromis niloticus followed by Hoplias malaricus, ominivorous/detritivotous and piscivorous species, respectively, presented the highest frequency of nuclear abnormalities, especially notched cells, while the herbivorous Astyanax bimaculatus lacustres showed the lowest frequency compared to the other species studied. Thus, for biomonitoring aquatic genotoxins under field conditions, the food web should also be considered

Knowledge Hub on the Integrated Assessment of Chemical Contaminants and their Effects on the Marine Environment

In a time of environmental awareness, spurred on by the possibility that our world is threatened by climate change, it is important to remember that there are other anthropogenic pressures, which are also essential for addressing the protection of the marine and coastal environment. Pollution is a global, complex issue that contributes to biodiversity loss and poor environmental health and comes from the production and release of many of the synthetic chemicals that we use in our daily lives. Chemical contaminants are often underrepresented as a major contributor of environmental deterioration. The Joint Programming Initiative Healthy and Productive Seas and Oceans (JPI Oceans) established in 2018 the JPI Oceans Knowledge Hub on the integrated assessment of chemical contaminants and their effects on the marine environment. The purpose of the Knowledge Hub was to provide recommendations on how to improve the methodological basis for marine chemical status assessment. The work has resulted in the following policy paper which focuses on improving the efficiency and implementation of integrated assessment methodology of effects of chemicals of emerging concern. Substantial additional knowledge of biological effects is needed to achieve Good Environmental Status (GES) of our oceans and coastal areas. The Knowledge Hub is represented by highly skilled scientists and policy makers, appointed by the JPI Oceans Management Board, to ensure that the recommendations provided are useful for policy making

Integrated biological effects and chemical contaminants approach: a case study

The OSPAR Maritime Area receives chemical pressure from approximately 140 000 hazardous substances. In the context of global change, the in situ assessment of the biological effects of chemical contaminants has achieved significant progress in standardising methodology over the past decade. An integrated approach on the biological effects of chemical contaminants has been developed for monitoring. Three methodological criteria were applied: 1) Common reference methods, 2) Quality assurance, and 3) Chemical and biological effect thresholds. Effect thresholds (EAC: Environmental Assessment Criteria) and baseline levels (BAC: Background Assessment Concentration) are unique in ecotoxicology. They were produced from monitoring data collected in the OSPAR Maritime Area. The monitoring expertise shared by OSPAR Contracting Parties over the last ten years is illustrated here by different case studies carried out under voluntary national monitoring programmes, in both coastal and offshore areas, in sites with contrasted contamination patterns, and in the short and long term. They apply a combination of biomarkers and chemical contaminants from a core list of sentinel species that were selected according to their spatial distribution (cod, herring, sole, eelpout, whiting, and saithe, as well as the broadly distributed mussel, flounder, dab, and gastropods). This original OSPAR monitoring approach forms the basis of the Marine Strategy Framework Directive’s descriptor 8 (contaminants and effects) and also contributes to the assessment of chemical exposome in the marine environment, a real challenge for the coming years.Peer reviewe