Perspectives on Relevancy Assessment for Non-Standard Ecotoxicity Data in Environment Quality Standard derivation: Examples for Diclofenac.

A key step in deriving an Environmental Quality Standard (EQS) is assessing the reliability and relevance of the underpinning ecotoxicity data. While the assessment of data reliability is relatively well established, the detailed evaluation of data relevancy is a more recent development. We applied broadly accepted relevancy criteria to a series of non-standard ecotoxicity studies on diclofenac, focusing on some aspects that should be accounted for in studies used in EQS derivation. Specific relevancy issues include potential experimental bias, claimed 'significant effects' that are indistinguishable from controls, or within the range of normal, and lack of environmental applicability. We highlight that rigorous, comprehensive and, where necessary, specialist assessment of data relevancy for studies potentially applicable for EQS setting is critical if studies are to be appropriately used regulatory decision-making. We provide recommendations for researchers and environmental practitioners to ensure robust accounting of relevancy in non-standard studies is undertaken.

Assessment of environmental quality of water bodies next to agricultural areas of Buenos Aires province (Argentina) by means of ecotoxicological studies with Rhinella arenarum.

Little is known about the effects of polluted water bodies from Buenos Aires Province on the development of native fauna. Ecotoxicological quality of water bodies from agricultural sites was evaluated by means of standardized laboratory bioassays with embryos and larvae of the native amphibian Rhinella arenarum. The organisms were acutely and chronically exposed to surface water samples from streams of Arrecifes (A), Pergamino (P) and Salto (S) districts that represent the most important agricultural core from the region. Lethal, sublethal and genotoxic effects were assessed. Water sample from (A) caused chronic toxicity (LC50:45.35%) in embryos, followed by (S) and the water sample from (P) was not toxic. In larvae, an inversion of the toxicity pattern was found. Thus, the 504 h-LC50s were 28.12%, 39% and 61% for (S), (P) and (A), respectively. A stage-dependent sensitivity was registered, being larvae more affected than embryos. Significant genotoxic effects, estimated by micronucleus test were observed in the larvae exposed to water samples from all sites. The present study warns about environmental degradation of surface waters next to agricultural areas of Buenos Aires Province. This fact jeopardizes R. arenarum populations in this area.

Distribution, accumulation profile, and risk assessment of polybrominated diphenyl ethers in sediment from lake and river systems in Hanoi Metropolitan Area, Vietnam.

Concentrations of seven polybrominated diphenyl ethers (PBDEs) congeners were determined in surface sediments collected from several rivers and lakes in Hanoi, the capital city of Vietnam, to understand the status of background contamination, accumulation pattern, sources, and toxic implications for benthic organisms. Total PBDE concentrations in all sediment samples ranged from 0.03 to 17.5 ng/g dry weight (mean 1.33 ng/g dry wt). The most predominant congeners were BDE-47 and BDE-99, which comprised 30 and 25 % of total PBDE concentrations, respectively. Results from statistical analysis indicated that the potential sources of PBDEs of sediments in Hanoi may come from penta-BDE and octa-BDE mixtures. Risk quotients of PBDEs in sediments were also calculated for a benthic species, ranged from 2.12 × 10-6 - 1.60 × 10-2, and were markedly lower than threshold value for occurrence of any ecotoxicological risk. This study provides some of the most comprehensive data on the occurrence of PBDEs in sediments from lake and river systems in Vietnam.

Looking at biological community level to improve ecotoxicological assessment of freshwater sediments: report on a first French-Swiss workshop.

The first French-Swiss workshop on ecotoxicology of freshwater sediment communities was co-organized by the French Research Institute of Science and Technology for Environment and Agriculture (Irstea) and the Swiss Centre for Applied Ecotoxicology (Ecotox Centre EAWAG-EPFL) in Villié-Morgon (Beaujolais Region, France) on April 27-28, 2017. The workshop brought together scientists working in different fields of expertise (ecotoxicologists, ecologists, environmental chemists…), environmental stakeholder groups and managers, as well as economic players (start-ups and consultancies) to better connect research needs of potential end-users with research outputs. The objectives of this workshop were (i) to establish the state of the art of research in the characterization of sediment contamination and in the evaluation of the effects on sediment-associated biological communities and ecosystem functioning and (ii) to give an overview of the French and Swiss regulations dealing with the assessment of contaminated sediments in freshwater ecosystems. The ultimate goal was to collectively identify research needs and knowledge gaps, as well as to highlight ways to improve the ecotoxicological assessment of sediments in freshwater environments by further considering the structure and functions of associated microbial and invertebrate communities.

Systematic Omics Analysis Review (SOAR) tool to support risk assessment.

Environmental health risk assessors are challenged to understand and incorporate new data streams as the field of toxicology continues to adopt new molecular and systems biology technologies. Systematic screening reviews can help risk assessors and assessment teams determine which studies to consider for inclusion in a human health assessment. A tool for systematic reviews should be standardized and transparent in order to consistently determine which studies meet minimum quality criteria prior to performing in-depth analyses of the data. The Systematic Omics Analysis Review (SOAR) tool is focused on assisting risk assessment support teams in performing systematic reviews of transcriptomic studies. SOAR is a spreadsheet tool of 35 objective questions developed by domain experts, focused on transcriptomic microarray studies, and including four main topics: test system, test substance, experimental design, and microarray data. The tool will be used as a guide to identify studies that meet basic published quality criteria, such as those defined by the Minimum Information About a Microarray Experiment standard and the Toxicological Data Reliability Assessment Tool. Seven scientists were recruited to test the tool by using it to independently rate 15 published manuscripts that study chemical exposures with microarrays. Using their feedback, questions were weighted based on importance of the information and a suitability cutoff was set for each of the four topic sections. The final validation resulted in 100% agreement between the users on four separate manuscripts, showing that the SOAR tool may be used to facilitate the standardized and transparent screening of microarray literature for environmental human health risk assessment.

Environmental and health impacts of fine and ultrafine metallic particles: assessment of threat scores.

This study proposes global threat scores to prioritize the harmfulness of anthropogenic fine and ultrafine metallic particles (FMP) emitted into the atmosphere at the global scale. (Eco)toxicity of physicochemically characterized FMP oxides for metals currently observed in the atmosphere (CdO, CuO, PbO, PbSO(4), Sb(2)O(3), and ZnO) was assessed by performing complementary in vitro tests: ecotoxicity, human bioaccessibility, cytotoxicity, and oxidative potential. Using an innovative methodology based on the combination of (eco)toxicity and physicochemical results, the following hazard classification of the particles is proposed: CdCl2~CdO>CuO>PbO>ZnO>PbSO(4)>Sb(2)O(3). Both cadmium compounds exhibited the highest threat score due to their high cytotoxicity and bioaccessible dose, whatever their solubility and speciation, suggesting that cadmium toxicity is due to its chemical form rather than its physical form. In contrast, the Sb(2)O(3) threat score was the lowest due to particles with low specific area and solubility, with no effects except a slight oxidative stress. As FMP physicochemical properties reveal differences in specific area, crystallization systems, dissolution process, and speciation, various mechanisms may influence their biological impact. Finally, this newly developed and global approach could be widely used in various contexts of pollution by complex metal particles and may improve risk management.

Identification of the most influential factors in the Norwegian guidelines for risk assessment of dispersion of contaminants from sediments.

The Norwegian guidelines for risk assessment of contaminated sediments are used to identify areas of concern where remediation may be needed to meet the governmental long-term goal of clean fjords and harbors along the Norwegian coastline. By a thorough sensitivity analysis, this study identifies the most influential factors and parameters for the Tier 2A model in this risk guideline, which are used to estimate fluxes of contaminants from sediments due to diffusion and bioturbation (F(diff)), resuspension caused by ship traffic (F(skipnorm)), and uptake and predation of benthic biota (F(org)). The sensitivity analysis is run for 36 different scenarios combining 3 different sizes of contaminated area, 3 harbor types, and 3 persistent organic pollutants, namely lindane (γ-hexachlorocyclohexane), benzo[a]pyrene, and 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153), as well as the metal mercury (Hg). The most influential parameters vary from scenario to scenario, but generally 5 parameters appear to be particularly influential for the fluxes and transport estimated by the Tier 2A model: flux of organic carbon to sediment (OC(sed)), factor for increased diffusion due to bioturbation (a), sediment-water partitioning coefficient (K(d)), benthic biota-water bioconcentration factor (BCF(fisk)), and mass of resuspended fine sediment during arrival or departure of a ship (m(sed)). We also quantify which of the 3 fluxes (F(diff), F(skipnorm), and F(org)) dominate in the different scenarios. Our sensitivity analysis results can be used by authorities, problem owners, consultants, and environmental managers involved in contaminated sediment management to gain insight on the key processes and parameters and to focus their site-specific or laboratory-based measurement efforts on the key parameters and thus increase efficiency and reliability in the contaminated sediment risk assessment.

Science based guidance for the assessment of endocrine disrupting properties of chemicals.

The European legislation on plant protection products (Regulation (EC) No. 1107/2009) and biocides (Directive 98/8/EC), as well as the regulation concerning chemicals (Regulation (EC) No. 1907/2006 'REACH') only support the marketing and use of chemical products on the basis that they do not induce endocrine disruption in humans or non-target species. However, there is currently no agreed guidance on how to identify and evaluate endocrine activity and disruption. Consequently, an ECETOC task force was formed to provide scientific criteria that may be used within the context of these three legislative documents. Specific scientific criteria for the determination of endocrine disrupting properties that integrate information from both regulatory (eco)toxicity studies and mechanistic/screening studies are proposed. These criteria combine the nature of the adverse effects detected in studies which give concern for endocrine toxicity with an understanding of the mode of action of toxicity so that adverse effects can be explained scientifically. The criteria developed are presented in the form of flow charts for assessing relevant effects for both humans and wildlife species. In addition, since not all chemicals with endocrine disrupting properties are of equal hazard, assessment of potency is also proposed to discriminate chemicals of high concern from those of lower concern. The guidance presented in this paper includes refinements made to an initial proposal following discussion of the criteria at a workshop of invited regulatory, academic and industry scientists.

Toxicity profiling: An integrated effect-based tool for site-specific sediment quality assessment.

A toxicity profile is a toxicological "fingerprint" of an environmental sample, obtained by testing its extract in a battery of bioassays. Each represents a different mode of action. The present work explores the applicability of in vitro toxicity profiles as an effect-based tool for sediment quality assessment. For this purpose, a previously published dataset was used, in which sediment extracts from 15 different locations in the Rhine-Meuse estuary were tested in 5 different bioassays. Three useful approaches could be distinguished for applying toxicity profiles in sediment quality assessment. In the first approach, toxicity profiles are translated into hazard profiles, indicating the relative distance to the desired or acceptable sediment quality status for each toxic mode of action. Hazard profiles can be considered as location-specific characteristics; sampling locations with similar hazard profiles can be classified into clusters. This approach seems directly applicable but requires a very careful selection of a reference toxicity profile that is either measured at a reference location or is designated as a desirable or acceptable toxicity profile for that particular location. In the second approach, toxicity profiles are translated into ecological risk profiles indicating for each toxic mode of action the ratio between the actual measured bioassay response and the bioassay response level that is considered safe for environmental health. This approach has a high ecological relevance but is only feasible for a few modes of action for which toxicity data are available at the ecological level of population or higher that allow derivation of ecologically safe bioassay responses for sediment extracts. In the third approach, toxicity profiles and their derived hazard profiles are used to select samples with unusually or unexpectedly high bioassay responses for further in-depth effect-directed analysis (EDA). EDA is a powerful strategy to identify emerging compounds that contribute significantly to the toxic load on the environment. EDA is an expensive and laborious strategy, however, making it currently suitable only for investigative monitoring on a limited scale and not for routine monitoring. Future perspectives in toxicity profiling include expansion of the battery of bioassays with test methods that cover other toxic endpoints or multiple endpoints, are high throughput, and improve the ecological relevance.

An Integrated Assessment Scheme for assessing the adequacy of (eco)toxicological data under REACH.

REACH requires all available (eco)toxicological information, whether protocol studies, other experiments, or non-testing approaches such as read-across or (Q)SAR, to be collected and evaluated. However, guidance documents only limitedly address how adequacy of (eco)toxicological information can be assessed consistently and transparently. We propose an Integrated Assessment Scheme (IAS) for the evaluation of (eco)toxicological data. The IAS consists of three modules: (i) the reliability of the data; (ii) the validity of the methods the data are generated from and; (iii) the regulatory need of the data. Each module is assessed and documented using adjusted OECD principles for the validation of (Q)SARs. These adjusted principles provide a harmonised set of criteria for the evaluation of all types of (eco)toxicological data. Assessment codes, similar to Klimisch codes, are assigned to the evaluated information in each module. The coherent combination of the assessment codes of all three modules determines the overall adequacy of information for fulfilling the information requirement in REACH, and can serve as a weight in a Weight of Evidence procedure as mentioned in REACH Annex XI.

General recommendations for soil ecotoxicological tests suitable for the environmental risk assessment of genetically modified plants.

Before a genetically modified plant (GMP) can be placed on the market in the European Union (EU), an environmental risk assessment has to be conducted according to EU-Directive 2001/18/EC or Regulation (EC) No. 1829/2003 of the European Parliament and of the Council. However, no harmonized concept for ecotoxicological testing is available today that considers the characteristics of GMPs as a whole. In fact, to date, mainly ecotoxicological tests originally developed and standardized for pesticides are used for this purpose. Frequently in these tests, not the whole GMP is tested but only specific transgene products (mainly toxins). In this contribution, ecotoxicological methods developed for the testing of pesticides are evaluated for whether they are suitable for risk assessment of GMPs as well. In total, 105 test methods covering a wide range of terrestrial invertebrates, microbes, and plants (laboratory, semifield, and field levels) were assessed. Only 7 of them had already been used with GMPs, and in about 20 studies the existing tests methods were modified, mostly in a way such that nonstandard species were used. In the laboratory, few earthworm and nontarget arthropod (NTA) species as well as collembolans and isopods were tested, and, in the field, only the litter-bag test was used. Clearly, more species than these few standard organisms currently in use have to be selected for testing purposes. A more detailed analysis of GMP tests with soil invertebrates published in the literature revealed that some of the relevant GMP exposure routes, such as via bulk soil, soil porewater, and litter from GMPs, are well covered. However, studies addressing either consumption of GMPs themselves or secondary exposure after GMPs have been taken up by invertebrates that feed on living or dead GMPs are underrepresented.

The challenge of making ozone risk assessment for forest trees more mechanistic.

Upcoming decades will experience increasing atmospheric CO2 and likely enhanced O3 exposure which represents a risk for the carbon sink strength of forests, so that the need for cause-effect related O3 risk assessment increases. Although assessment will gain in reliability on an O3 uptake basis, risk is co-determined by the effective dose, i.e. the plant's sensitivity per O3 uptake. Recent progress in research on the molecular and metabolic control of the effective O3 dose is reported along with advances in empirically assessing O3 uptake at the whole-tree and stand level. Knowledge on both O3 uptake and effective dose (measures of stress avoidance and tolerance, respectively) needs to be understood mechanistically and linked as a pre-requisite before practical use of process-based O3 risk assessment can be implemented. To this end, perspectives are derived for validating and promoting new O3 flux-based modelling tools.