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A variety of hydrokinetic turbines are currently under development for power generation in rivers, tidal straits and ocean currents. Because some of these turbines are large, with rapidly moving rotor blades, the risk of collision with aquatic animals has been brought to attention. The behavior and fate of animals that approach such large hydrokinetic turbines have not yet been monitored at any detail. In this paper, we conduct a synthesis of the current knowledge and understanding of hydrokinetic turbine collision risks. The outcome is a generic fault tree based probabilistic model suitable for estimating population-level ecological risks. New video-based data on fish behavior in strong currents are provided and models describing fish avoidance behaviors are presented. The findings indicate low risk for small-sized fish. However, at large turbines (≥5 m), bigger fish seem to have high probability of collision, mostly because rotor detection and avoidance is difficult in low visibility. Risks can therefore be substantial for vulnerable populations of large-sized fish, which thrive in strong currents. The suggested collision risk model can be applied to different turbine designs and at a variety of locations as basis for case-specific risk assessments. The structure of the model facilitates successive model validation, refinement and application to other organism groups such as marine mammals.

The objective of this study was to identify subareas inside and near an Atlantic Rain Forest reserve, the Parque Estadual Turistico do Alto Ribeira (PETAR), most likely to be affected by land use in the vicinity of the area. In addition, the study aimed to compare risks per stressor source (agriculture, human settlements and mining) to both epigean (surface) and hypogean (subterranean) aquatic fauna. The methodological approach included the relative vulnerability of endpoints to the stressors (pesticides, metals, nutrients, and particles) and ranking of stressor sources and habitats (epigean and hypogean streams) based on their relative distribution in 14 subareas within the catchment areas of the main rivers that cross PETAR:Piloes, Betari and Iporanga. Four subareas presented high risk for both epigean and hypogean fauna. Three of those areas were located inside the Betari catchment area, where most of the settlements andabandoned lead mines are located. The fourth area was situated in the headwaters of the Piloes River, where agricultural activities are intense. Agriculture and human settlements were the activities most likely to cause impacts on aquatic ecosystems. Uses of risk assessment results include management of the PETAR and communication to stakeholders by the Park Administration.

Rockström et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if “unacceptable global change” is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent, as well as readily degradable chemicals released at local to regional scales, which in aggregate threaten ecosystem and human viability. The PBCP allows humanity to explicitly address the increasingly global aspects of chemical pollution throughout a chemical's life cycle and the need for a global response of internationally coordinated control measures. We submit that sufficient evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step forward, at this point single or multiple PBCPs are challenging to operationalize due to the extremely large number of commercial chemicals or mixtures of chemicals that cause myriad adverse effects to innumerable species and ecosystems, and the complex linkages between emissions, environmental concentrations, exposures and adverse effects. As well, the normative nature of a PBCP presents challenges of negotiating pollution limits amongst societal groups with differing viewpoints. Thus, a combination of approaches is recommended as follows: develop indicators of chemical pollution, for both control and response variables, that will aid in quantifying a PBCP(s) and gauging progress towards reducing chemical pollution; develop new technologies and technical and social approaches to mitigate global chemical pollution that emphasize a preventative approach; coordinate pollution control and sustainability efforts; and facilitate implementation of multiple (and potentially decentralized) control efforts involving scientists, civil society, government, non-governmental organizations and international bodies. Keywords: Planetary boundary, Chemical pollution, Chemical emissions, Stockholm Convention, Tipping point, Global threshold, Pollution controls, Ecosystem health protection, Human health protection, Chemical management

One promising future bulk application of graphene is as composite additive. Therefore, we compare two production routes for in-solution graphene using a cradle-to-gate lifecycle assessment focusing on potential differences in energy use, blue water footprint, human toxicity, and ecotoxicity. The data used for the assessment is based on information in scientific papers and patents. Considering the prospective nature of this study, environmental impacts from background systems such as energy production were not included. The production routes are either based on ultrasonication or chemical reduction. The results show that the ultrasonication route has lower energy and water use, but higher human and ecotoxicity impacts, compared to the chemical reduction route. However, a sensitivity analysis showed that solvent recovery in the ultrasonication process gives lower impacts for all included impact categories. The sensitivity analysis also showed that solvent recovery is important to lower the blue water footprint of the chemical reduction route as well. The results demonstrate the possibility to conduct a life cycle assessment study based mainly on information from patents and scientific articles, enabling prospective life cycle assessment studies of products at early stages of technological development.

Exposure assessment of engineered nanoparticles (ENPs) is a challenging task mainly due to the novel properties of these new materials and the complexity caused by a wide range of particle characteristics, ENP-containing products and possible environmental interactions. We here present a research agenda in which we propose to face the complexity associated with ENP exposure assessment through informed and systematic simplifications. Exposure modelling is presented as a method for addressing complexity by identifying processes dominant for the fate of ENPs in the environment and enabling an iterative learning process by studying different emission and fate scenarios. Furthermore, the use of models is important to highlight most pressing research needs. For this reason, we also strongly encourage improved communication and collaboration between modellers and experimental scientists. Feedback between modellers and experimental scientists is crucial in order to understand the big picture of ENP exposure assessment and to establish common research strategies. Through joint research efforts and projects, the field of ENP exposure assessment can greatly improve and significantly contribute to a comprehensive and systematic risk assessment of ENPs.

The effect of tri-n-butyl tin (TBT) on an intact marine sediment community after five months exposure was investigated. Changes in the structure of macro- and meiofauna communities were determined, as well as the functional diversity of the microbial community using BIOLOG microplates for Gram negative bacteria. Development of tolerance in the microbial community was investigated using Pollution Induced Community Tolerance (PICT) experiments with fluxes of nutrients as effect indicators. TBT affected the structure and recruitment of the macro- and meiofauna at nominal additions of 30-137 micromol TBT/m2 sediment. Number of species, diversity, biomass and community similarity was reduced at these concentrations compared to control. Species that molt seemed to be the most tolerant since they were predominant in boxes that had received the highest TBT addition and echinoderms were the most sensitive species. Renewed addition of TBT in PICT experiments with sediment from each boxcosm showed that TBT had an effect on individual nutrient fluxes from all sediments. Analyses of the flux patterns revealed a memory of previous TBT exposure, either due to induced tolerance or other community conditioning.

Tri-n-butyltin (TBT) has been used in the marine environment as a toxic agent in antifouling paints, but unfortunately it also has negative effects on non-target organisms in the environment. In this study, intact coastal sediment was exposed for seven months to three levels of TBT corresponding to nominal additions of 0.00, 0.02 and 2.00 nmol TBT per g dry sediment. This paper presents the first attempt to find out how living benthic foraminifera respond to TBT. Increased foraminiferal abundance in the 0.02 nmol mesocosm could be an effect of decreased predation (competition), since other representatives of meiofauna and macrofauna tended to be less tolerant to TBT. Increasing toxicity in the most contaminated mesocosm group (2.00 nmol) resulted in a less abundant foraminiferal population suggesting that TBT affects the foraminiferal community.

Life cycle assessment (LCA) methodology was used to compare the environmental loads from wastewater systems with different technical solutions. This study compared proposed conventional wastewater systems, both large and small scale, with separation systems: one in which urine is handled separately and one in which black water is treated in a liquid composting process. The study showed that large economies of scale, in environmental terms, could be gained both for the operation and for the construction phase. The separation systems outperformed the conventional systems by showing lower emissions to water and more efficient recycling of nutrients to agriculture, especially of nitrogen but also of phosphorus. This implies that the use of separation systems could significantly reduce the need for, and hence the production of, mineral fertilizers and thus reduce the overall use of energy and phosphate minerals. The combination of large-scale wastewater treatment and urine separation was found to be especially advantageous in these respects. It is concluded that some of the most important environmental advantages of separation systems emerge only when models of wastewater systems are expanded to also include potential effects on the production of fertilizers.

A new data model has been developed to handle information relevant to site-specific life cycle assessments (LCA). The model is orientated towards GIS-representations of three generalised subsystems; the technical, the environmental and the social subsystems. The technical and environmental systems are mainly linked through flows of energy and matter, which are the causes of environmental impacts, which subsequently is perceived, evaluated and acted upon by the social subsystem. For all three systems important differences, attributable to geographical locations can be determined. With the new data model a possibility to enhance LCA and reach more relevant results emerge due to a higher site specificity. The high level data model is expressed as relations between different entities using the entity relationship (ER) modelling language. An existing LCA-database, SPINE, which is already used by several companies for decision support in product development, can be utilised since the structure of the database supports geographical information. So far, applications with GIS-data are limited, but examples of area specific LCA impact characterisation factors exist.

Estimating the size of the problems related to release, fate, exposure and effects from the human use of chemical substances in materials and consumer products is daunting. More than 100,000 chemical substances are in commercial use and a reasonable description of their existence in, and release from, plastic polymers, glues, paints, fibres, lubricants etc. comprise a big challenge. Here we report the initial results from a generic emission model that has been developed and applied to estimate emissions of a set of organic chemicals from products. The scope of the study was to estimate emissions from products containing plastic materials during their average lifetime within the geographical boundaries of Sweden. The results show that approximately 2% of the plastic additives are emitted annually. Plasticisers, flame retardants, organic pigments and stabilisers are the use categories of additives that are emitted in the largest quantities. Until now, the method has only been used to estimate emissions of additives from plastic materials, but it is believed to also be applicable to other materials.

The effects of combined toxicity were studied, using marine periphyton communities exposed to mixtures of tri-n-butyl tin (TBT) and diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea, DCMU) in indoor aquaria during four weeks. The experimental design of the study followed a central composite design (CCD) and utilized dose-response surface methodology for evaluation of the results. The detection of pollution-induced community tolerance (PICT) was accomplished by short-term (1 h) tests on inhibition of photosynthesis. Both single-toxicant and two-toxicant short-term tests were used. Two tentative measures of tolerance are proposed to achieve convenient comparisons of the tolerances from the two-toxicant tests. With the detection of PICT, effects of the long-term exposure were recorded on diatom species richness, chlorophyll a accumulation and copepod abundance. The decrease of diatom species richness was accompanied by an increased tolerance (PICT), which was detectable by all tolerance measures used. Primary effects on microalgae were recorded as a decrease in chlorophyll a at higher toxicant concentrations. At lower concentrations, primary effects on copepods were found, which resulted in reduced grazing and increased chlorophyll a content.

In the present work an effort aiming at a partial validation of the pollution-induced community tolerance (PICT) methodology is reported. Periphyton communities were established on artificial substrata in a marine microcosm system for 3 to 4 weeks. The communities were exposed to concentrations of the herbicide diuron (DCMU, 3-(3.4-dichlorophenyl)-1.1-dimethyl urea) ranging from 1.6 nM to 1 μM. A short-term test on periphyton photosynthesis was used to quantify the tolerances of the different communities, and an increase in the tolerance (PICT) was detected at concentrations above 40 nM. The results are discussed in terms of a ‘comparison triad’ where comparisons are made between the short-term effects on photosynthesis of control communities, the PICT of diuron-exposed communities, and other long-term effects such as cholorophyll a content, specific pholosynthetic activity (P) and diatom species richness. The first effect of diuron on periphyton photosynthesis in short-term tests was recorded at about 3.2 nM. while effects after long-term exposure, reflected by the various long-term parameters, were detectable only at higher concentrations, about 20 to 40 nM.

Periphyton communities established on artificial substrates in a brackish-water mesocosm test system and in a marine microcosm test system were exposed to 4,5,6-trichloroguaiacol (456TCG) and monitored for effects on biomass, species composition and short-term tolerance of CO 2 -incorporation. In the brackish-water mesocosms no effects on biomass or species composition were correlated to the 456TCG exposures in the range of 1.7 to 50 nM. EC 20 of 456TCG for short-term effects on periphyton CO 2 -incorporation were in all cases, including periphyton from a field reference station, between 1 and 12 μM. Periphyton from the marine microcosm system showed the same short-term tolerance of CO 2 -incorporation as periphyton from the brackish-water experiments and the marine field reference station, except at the pre-exposure level of 32 μM, where a marked increase occurred. The pre-exposure of 32 μM is higher than the short-term EC 20 of all periphyton communities exposed to lower pre-exposure concentrations. This is in accordance with the concept of Pollution Induced Community Tolerance (PICT) (Blanck et al., 1988), which states that a toxicant acting as a selection pressure on a community causes a tolerance increase due to exclosure of sensitive species and/or individuals from the community. The periphyton community exposed to 32 μM showed both an increased short-term tolerance, a decreased species number, and a decreased concentration of chlorophyll a . Two metabolites were identified in the periphyton of the microcosm test system, 3,4,5-trichlorocatechol (345TCC) and 3-bromo-4,5,6-trichlorocatechol (BTCC). A dimeric biotransformation product was also found in the periphyton. Acid hydrolysis of both water and periphyton samples gave an increase in the amounts of 456TCG and metabolites, indicating a large proportion of the compounds being bound or conjugated.

A marine mesocosm system (boxcosm system) was developed for ecological and/or ecotoxicological studies of sediment community function and structure. The system consists of continuous flow-through incubations of intact sediment samples, each with a surface area of 0.25 m2. The experimental setup enables repeated non-destructive measurements of benthic fluxes, such as of nutrients, oxygen and dissolved inorganic carbon, over the sediment–water interface. The benthic fluxes reflect the function of the sediment community, integrating over the chemical, biological and physical activities in the sediment. The suitability of the boxcosm system for controlled, highly ecologically relevant studies of intact sediment communities was evaluated in two experiments of six weeks and five months duration respectively, where the functional and structural development over time was compared to the development of the sampling site. The function of the sediment was measured as nutrient and oxygen fluxes, and the structural component consisted of microbial functional diversity and meio- and macrofauna composition. Differences between the boxcosm and the sampling site were detected especially in nitrate fluxes and meiofauna diversity and abundance, but all differences fell within seasonal and inter-annual variability at the sampling site. The cause of the differences could be referred to differences in oxygen availability, supply of organic matter particles, and recruitment of larvae. These factors can however be compensated for within the present setup. The study shows that the boxcosms are suitable tools for ecologically relevant studies generating comparable conditions to the natural environment.

The sustainability of an urban water system was studied by application of a set of indicators that focuses on environmental issues and the efficiency and performance of the technical system. Temporal variations of indicators reflecting freshwater resources, drinking water, wastewater and by-products, were investigated for the water and wastewater system in Göteborg. Extended time series of precise data were available for quantitative indicators such as water consumption, energy use and discharge loadings. Qualitative indicators such as drinking water quality, sewage sludge quality and ecosystem status were more difficult to assess, a situation complicated by variations in criteria set in different countries. Although large urban water systems are often considered unsustainable, the set of indicators demonstrate that the water and wastewater system in Göteborg has moved towards a more sustainable status; recycling of nutrients to agriculture remains, though, a major concern.

S-413 19 G6teborg, Sweden PROBLEM AND APPROACH One of the most important sources of chlorinated organic �jmpounds found in the Baltic Sea is the bleaching step of the kraft pulp process. 4,5,6-trich10roguaiaco1 (TCG) is one of many identified chlorinated phenolics in b1eachery effluents. Ch1oroguaiaco1s have been considered as a potential environmental hazard because of their persistence, hydrophobicity and toxicity towards fish and algae (Renberg et a1., 1980; Anon., 1982; Kuivasniemi et a1., 1985). As part of a 10ng-term-exposure experiment using brackish-water littoral zone mesocosms this study was undertaken to examine the effects of TCG on periphyton communities with respect to species composition and biomass accumulation on an artificial substratum, and the induced community tolerance of periphyton photosynthesis to TCG. MATERIALS AND METHODS Periphyton communities were established on glass discs (area 1.6 cm2, 170 discs per pool) from 29 August 1985 to 27 September 1985 in five mesocosm pools designed to simulate the littoral ecosystem of the Baltic Sea. Three pools were exposed to nominal additions of 4, 43 and 220 nM (1, 10 and 50 Ilg/1) TCG respectively, two pools were controls; with and without solvent (ethanol 0.5 ppm). Periphyton was also sampled, with the same method, from a reference station in the Kar1skrona Archipelago. The methodology used for biomass and photosynthetic activity determinations mainly follows Blanck (1985) and

One of the most promising applications of graphene is as material in transparent electrodes in applications such as liquid crystal displays (LCDs) and solar cells. In this study, we assess life cycle resource requirements of producing an electrode area of graphene by chemical vapor deposition (CVD) and compare to the production of indium tin oxide (ITO). The resources considered are energy and scarce metals. The results show that graphene layers can have lower life cycle energy use than ITO layers, with 3–10 times reduction for our best case scenario. Regarding use of scarce metals, the use of indium in ITO production is more problematic than the use of copper in graphene production, although the latter may constitute a resource constraint in the very long run. The substitution of ITO by graphene thus seems favorable from a resource point of view. Higher order effects may outweigh or enhance the energy use benefit. For example, cheaper, graphene-based electrodes may spur increased production of LCDs, leading to increased absolute energy use, or spur the development of new energy technologies, such as solar cells and fuel cells. The latter could potentially lead to larger absolute reductions in resource use if these new technologies will replace fossil-based energy systems.

Goal, Scope and Background: The EU 5th framework project OMNIITOX will develop models calculating characterisation factors for assessing the potential toxic impacts of chemicals within the framework of LCA. These models will become accessible through a web-based information system. The key objective of the OMNIITOX project is to increase the coverage of substances by such models. In order to reach this objective, simpler models which need less but available data, will have to be developed while maintaining scientific quality. Methods. Experience within the OMNIITOX project has taught that data availability and quality are crucial issues for calculating characterisation factors. Data availability determines whether calculating characterisation factors is possible at all, whereas data quality determines to what extent the resulting characterisation factors are reliable. Today, there is insufficient knowledge and/or resources to have high data availability as well as high data quality and high model quality at the same time. Results: The OMNIITOX project is developing two inter-related models in order to be able to provide LCA impact assessment characterisation factors for toxic releases for as broad a range of chemicals as possible: 1) A base model representing a state-of-the-art multimedia model and 2) a simple model derived from the base model using statistical tools. Discussion. A preliminary decision tree for using the OMNIITOX information system (IS) is presented. The decision tree aims to illustrate how the OMNIITOX IS can assist an LCA practitioner in finding or deriving characterisation factors for use in life cycle impact assessment of toxic releases. Conclusions and Outlook: Data availability and quality are crucial issues when calculating characterisation factors for the toxicity impact categories. The OMNIITOX project is developing a tiered model approach for this. It is foreseen that a first version of the base model will be ready in late summer of 2004, whereas a first version of the simple base model is expected a few months later

The effect of tri-n-butyl-tin (TBT) was studied in a 5 mo experiment using intact coastal sediment communities in a boxcosm system. TBT-spiked sediment was added in a geometrical series between 0.0065 and 300 mu mol TBT m(-2) to a sediment that already had a background TBT concentration. Fluxes of ammonium, nitrate, phosphate, silicate and oxygen were used as effect indicators for the entire sediment system, integrating the function of all fauna and micro-organisms present. Changes in flux patterns were analysed in order to evaluate the effect of TBT on the whole sediment system using a non-parametric analysis of similarities (ANOSIM), based on Bray-Curtis similarity indices. Effects were seen at the lowest additions of 6.5 nmol TBT m(-2) as changes in flux pattern compared to the control sediments. The separate nutrient fluxes were also evaluated, showing an early response in a reduced ammonium flux and a stimulated nitrate flux for most of the TBT additions. The initial response indicated immediate effects on the microbial part of the sediment community. The fluxes changed with time in all sediment boxes, but the changes were different in sediments with added TBT compared to the control sediment. These changes showed that the heterotrophic capability to degrade organic matter and autotrophic nitrification was reduced during the 5 mo of the experiment. In the 3 highest additions, the abundance of macrofauna was reduced at the very beginning of the experiment, whereas fauna in the intermediate additions seemed to become stressed with time as indicated by an increased oxygen consumption. This study shows that minute additions of fresh TBT to an already contaminated sediment have effects on the function of the sediment system at nominal concentrations of nmol of TBT added per square metre. These additions were well below the current detection limits for TBT in sediments.

This study evaluates causal relationships between chronic exposure of fish to metals and effects at different levels of biological organization based on a weight-of-evidence approach. Criteria for evaluation of causality were strength, consistency, and specificity of the association, as well as biological gradient and plausibility. Field sampling was conducted three times between 1998 and 2000, in Furnas Stream, impacted by an abandoned lead mine, and in three other locations, including two reference and one impacted sites. Levels of Pb, Zn, Cd, and Ag in sediments from the Furnas Stream exceeded background levels, and their concentrations were above sediment quality guidelines. Residual levels of metals in fish tissue were high enough to indicate reduced growth, reproduction and/or survival according to toxicological benchmarks. Lead-induced biochemical changes (ALA-D activity depletion) were observed in two species of siluriform catfish. The condition factor of a predatory catfish was reduced, and the percentage of prey generalists was higher in Furnas than at the noncontaminated sites. Reduction in fish community diversity and density was observed. Integration of data provided supporting evidence that observed effects on fish from the Furnas Stream resulted from long-term exposure to metals, however influences from other stressors cannot be ruled out.