| 1. |
- Persson, L., et al.
(författare)
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Outside the Safe Operating Space of the Planetary Boundary for Novel Entities
- 2021
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 56:3, s. 1510-1521
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Tidskriftsartikel (refereegranskat)abstract
- We submit that the safe operating space of the planetary boundary of novel entities is exceeded since annual production and releases are increasing at a pace that outstrips the global capacity for assessment and monitoring. The novel entities boundary in the planetary boundaries framework refers to entities that are novel in a geological sense and that could have large-scale impacts that threaten the integrity of Earth system processes. We review the scientific literature relevant to quantifying the boundary for novel entities and highlight plastic pollution as a particular aspect of high concern. An impact pathway from production of novel entities to impacts on Earth system processes is presented. We define and apply three criteria for assessment of the suitability of control variables for the boundary: feasibility, relevance, and comprehensiveness. We propose several complementary control variables to capture the complexity of this boundary, while acknowledging major data limitations. We conclude that humanity is currently operating outside the planetary boundary based on the weight-of-evidence for several of these control variables. The increasing rate of production and releases of larger volumes and higher numbers of novel entities with diverse risk potentials exceed societies' ability to conduct safety related assessments and monitoring. We recommend taking urgent action to reduce the harm associated with exceeding the boundary by reducing the production and releases of novel entities, noting that even so, the persistence of many novel entities and/or their associated effects will continue to pose a threat. ©
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| 2. |
- Bogdal, Christian, et al.
(författare)
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Emissions of Polychlorinated Biphenyls, Polychlorinated Dibenzo-p-dioxins, and Polychlorinated Dibenzofurans during 2010 and 2011 in Zurich, Switzerland
- 2014
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 48:1, s. 482-490
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Tidskriftsartikel (refereegranskat)abstract
- Persistent organic pollutants (POPs) are ubiquitous contaminants of environmental and human health relevance, but their emissions into the environment are still poorly known. In this study, concentrations of selected POPs were measured in ambient air in Zurich, Switzerland, and interpreted with a multimedia mass balance model. The aim of the combination of measurements and modeling was to back-calculate atmospheric emission rates of POPs. Measurements were performed in summer 2010 and winter 2011 and target analytes included polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Estimated emissions were higher in summer than in winter. Emission estimates for Zurich can be extrapolated to annual averages for Switzerland of 312 kg·a–1 (39 mg·capita–1·a–1), 53 kg·a–1 (7 mg·capita–1·a–1), and 3 kg·a–1 (0.4 mg·capita–1·a–1, 94 g WHO98-TEQ·a–1, 65 g I-TEQ·a–1) for the six indicator PCBs (iPCBs), the twelve coplanar dioxin-like PCBs (dlPCBs), and the 17 2,3,7,8-chlorosubstituted PCDD/Fs, respectively. The emission rates of iPCBs are in agreement with existing emission inventories, whereas for PCDD/Fs the emissions are five times higher than the estimates from the Swiss national emission inventory. Emissions of dlPCBs in Switzerland are presented here for the first time. Our study also provides the first seasonally resolved emission rates of POPs, which were determined with our combined measurement and modeling approach. These findings highlight the relevance of ongoing sources of POPs, even decades after regulations aiming to reduce or eliminate sources were established.
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| 3. |
- Buser, Andreas M., et al.
(författare)
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Good modeling practice guidelines for applying multimedia models in chemical assessments
- 2012
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Ingår i: Integrated Environmental Assessment and Management. - : Wiley. - 1551-3777 .- 1551-3793. ; 8:4, s. 703-708
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Tidskriftsartikel (refereegranskat)abstract
- Multimedia mass balance models of chemical fate in the environment have been used for over 3 decades in a regulatory context to assist decision making. As these models become more comprehensive, reliable, and accepted, there is a need to recognize and adopt principles of Good Modeling Practice (GMP) to ensure that multimedia models are applied with transparency and adherence to accepted scientific principles. We propose and discuss 6 principles of GMP for applying existing multimedia models in a decision-making context, namely 1) specification of the goals of the model assessment, 2) specification of the model used, 3) specification of the input data, 4) specification of the output data, 5) conduct of a sensitivity and possibly also uncertainty analysis, and finally 6) specification of the limitations and limits of applicability of the analysis. These principles are justified and discussed with a view to enhancing the transparency and quality of model-based assessments.
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| 4. |
- Domercq, Maria del Prado, et al.
(författare)
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The Full Multi : An open-source framework for modelling the transport and fate of nano- and microplastics in aquatic systems
- 2022
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Ingår i: Environmental Modelling & Software. - : Elsevier BV. - 1364-8152 .- 1873-6726. ; 148
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Tidskriftsartikel (refereegranskat)abstract
- We present a freely available open-source modelling framework to explore environmental transport and fate of nano-and microplastics in aquatic systems. The “Full Multi” models 1) fragmentation of plastic into a predefined set of size classes, 2) speciation of plastic particles between pristine, heteroaggregated, biofouled, and biofouled & heteroaggregated species, 3) dynamic vertical exchange between water layers and sediment of a freshwater system, and 4) horizontal particle transport by eddy diffusion and advective flow. The Full Multi framework relates emission rates to environmental exposure concentrations while considering the intrinsic properties of plastic particles and variable environmental system properties. The model can be applied to analyse scenarios with different process descriptions, plastic types, emission routes and environmental parameters for hypothesis generation, to identify dominant fate processes, and in hazard and risk assessment. Here, we introduce and illustrate the framework by modelling plastic particles with a range of densities in a generic flowing river system.
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| 5. |
- Ebinghaus, Ralf, et al.
(författare)
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Berlin statement on legacy and emerging contaminants in polar regions
- 2023
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 327
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Tidskriftsartikel (refereegranskat)abstract
- Polar regions should be given greater consideration with respect to the monitoring, risk assessment, and management of potentially harmful chemicals, consistent with requirements of the precautionary principle. Protecting the vulnerable polar environments requires (i) raising political and public awareness and (ii) restricting and preventing global emissions of harmful chemicals at their sources. The Berlin Statement is the outcome of an international workshop with representatives of the European Commission, the Arctic Council, the Antarctic Treaty Consultative Meeting, the Stockholm Convention on Persistent Organic Pollutants (POPs), environmental specimen banks, and data centers, as well as scientists from various international research institutions. The statement addresses urgent chemical pollution issues in the polar regions and provides recommendations for improving screening, monitoring, risk assessment, research cooperation, and open data sharing to provide environmental policy makers and chemicals management decision-makers with relevant and reliable contaminant data to better protect the polar environments. The consensus reached at the workshop can be summarized in just two words: “Act now!”Specifically, “Act now!” to reduce the presence and impact of anthropogenic chemical pollution in polar regions by.•Establishing participatory co-development frameworks in a permanent multi-disciplinary platform for Arctic-Antarctic collaborations and establishing exchanges between the Arctic Monitoring and Assessment Program (AMAP) of the Arctic Council and the Antarctic Monitoring and Assessment Program (AnMAP) of the Scientific Committee on Antarctic Research (SCAR) to increase the visibility and exchange of contaminant data and to support the development of harmonized monitoring programs.•Integrating environmental specimen banking, innovative screening approaches and archiving systems, to provide opportunities for improved assessment of contaminants to protect polar regions.
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| 6. |
- Groh, Ksenia J., et al.
(författare)
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Assessing and managing environmental hazards of polymers : historical development, science advances and policy options
- 2023
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Ingår i: Environmental Science. - : Royal Society of Chemistry (RSC). - 2050-7887 .- 2050-7895. ; 25:1, s. 10-25
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Forskningsöversikt (refereegranskat)abstract
- Polymers are the main constituents of many materials and products in our modern world. However, their environmental safety is not assessed with the same level of detail as done for non-polymeric chemical substances. Moreover, the fundamentals of contemporary regulatory approaches for polymers were developed in the early 1990s, with little change occurring since then. Currently, the European Commission is working on a proposal to initiate registration of polymers under the European Union's (EU) chemicals legislation REACH. This provides a unique opportunity for regulation to catch up on recent scientific advances. To inform this process, we here critically appraise the suggested regulatory approaches to the environmental assessment and management of polymers against the latest scientific findings regarding their environmental fate, exposure, and effects, and identify the remaining critical knowledge gaps. While we use the EU draft proposal as an example, our findings are broadly applicable to other polymer legislations worldwide, due to the similarity of polymer assessment criteria being used. We emphasize four major aspects that require more attention in the regulation of polymers: (i) increased transparency about chemical identities, physical characteristics and grouping approaches for in-use polymers; (ii) improved understanding of the environmental fate of polymers and materials composed of polymers across size and density categories and exposure profiles; (iii) comprehensive assessment of the environmental hazards of polymers, considering the effects of degradation and weathering and taking into account the actual uptake, long-term toxicity, and geophysical impacts; and (iv) consideration of the production volume and use/release patterns in determining regulatory data and testing requirements. Transitioning toward a toxic-free and sustainable circular economy will likely require additional policy instruments that will reduce the overall complexity and diversity of in-use polymers and polymeric materials.
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| 7. |
- Hader, John D., et al.
(författare)
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Enabling forecasts of environmental exposure to chemicals in European agriculture under global change
- 2022
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 840
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Forskningsöversikt (refereegranskat)abstract
- European agricultural development in the 21st century will be affected by a host of global changes, including climate change, changes in agricultural technologies and practices, and a shift towards a circular economy. The type and quantity of chemicals used, emitted, and cycled through agricultural systems in Europe will change, driven by shifts in the use patterns of pesticides, veterinary pharmaceuticals, reclaimed wastewater used for irrigation, and biosolids. Climate change will also impact the chemical persistence, fate, and transport processes that dictate environmental exposure. Here, we review the literature to identify research that will enable scenario-based forecasting of environmental exposures to organic chemicals in European agriculture under global change. Enabling exposure forecasts requires understanding current and possible future 1.) emissions, 2.) persistence and transformation, and 3.) fate and transport of agricultural chemicals. We discuss current knowledge in these three areas, the impact global change drivers may have on them, and we identify knowledge and data gaps that must be overcome to enable predictive scenario-based forecasts of environmental exposure under global change. Key research gaps identified are: improved understanding of relationships between global change and chemical emissions in agricultural settings; better understanding of environment-microbe interactions in the context of chemical degradation under future conditions; and better methods for downscaling climate change-driven intense precipitation events for chemical fate and transport modelling. We introduce a set of narrative Agricultural Chemical Exposure (ACE) scenarios — augmenting the IPCC's Shared Socio-economic Pathways (SSPs) — as a framework for forecasting chemical exposure in European agriculture. The proposed ACE scenarios cover a plausible range of optimistic to pessimistic 21st century development pathways. Filling the knowledge and data gaps identified within this study and using the ACE scenario approach for chemical exposure forecasting will support stakeholder planning and regulatory intervention strategies to ensure European agricultural practices develop in a sustainable manner.
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| 8. |
- Hader, John, 1992-, et al.
(författare)
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Prioritizing toxic shock threats to sewage treatment plants from down-the-drain industrial chemical spills: the RAVEN STREAM online tool
- 2023
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Ingår i: Environmental Science: Advances. - : Royal Society of Chemistry (RSC). - 2754-7000. ; 2:9, s. 1235-1246
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Tidskriftsartikel (refereegranskat)abstract
- Down-the-drain chemical spills that reach a sewage treatment plant (STP) can cause a biological “toxic shock” that may reduce or eliminate the capability of STP microorganisms to remove organic matter and nutrients for weeks to months. Thus, chemical spills are a threat to water quality. Here, we present a case study of toxic shock threat prioritization for chemicals used at industrial facilities connected to the Käppala STP in Stockholm, Sweden. We surveyed 60 facilities, collected information on the use and storage of bulk chemical products, and documented 8676 uses of constituent chemicals. In situ chemical tracer experiments were conducted in the primary sewer tunnel leading to Käppala to measure chemical spill dilution during transit to the plant. To assess chemical risks to the plant, we extracted data on toxicity to STP microorganisms for 6168 chemicals from European Chemicals Agency brief profiles and estimated exposure concentrations in the plant using conservative assumptions. Under a high-end spill scenario, the majority of chemicals in the survey posed a negligible risk for adverse effects on plant microorganisms, however 28 chemicals were identified as posing a potential risk and were prioritized for additional information gathering to refine our conservative assumptions. The analysis framework was built into an online tool (RAVEN STREAM) provided as free, open-source software for STP operators to screen for threats posed by possible chemical spills at connected facilities. The threat identification framework can facilitate communication between STPs and their upstream industrial clients to mitigate possible high-risk chemical spills before they happen.
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| 9. |
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| 10. |
- Heffernan, Amy L., et al.
(författare)
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Pooled biological specimens for human biomonitoring of environmental chemicals : Opportunities and limitations
- 2014
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Ingår i: Journal of Exposure Science and Environmental Epidemiology. - : Springer Science and Business Media LLC. - 1559-0631 .- 1559-064X. ; 24:3, s. 225-232
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Forskningsöversikt (refereegranskat)abstract
- Biomonitoring has become the “gold standard” in assessing chemical exposures, and has an important role in risk assessment. The pooling of biological specimens—combining multiple individual specimens into a single sample—can be used in biomonitoring studies to monitor levels of exposure and identify exposure trends or to identify susceptible populations in a cost-effective manner. Pooled samples provide an estimate of central tendency and may also reveal information about variation within the population. The development of a pooling strategy requires careful consideration of the type and number of samples collected, the number of pools required and the number of specimens to combine per pool in order to maximise the type and robustness of the data. Creative pooling strategies can be used to explore exposure–outcome associations, and extrapolation from other larger studies can be useful in identifying elevated exposures in specific individuals. The use of pooled specimens is advantageous as it saves significantly on analytical costs, may reduce the time and resources required for recruitment and, in certain circumstances, allows quantification of samples approaching the limit of detection. In addition, the use of pooled samples can provide population estimates while avoiding ethical difficulties that may be associated with reporting individual results.
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| 11. |
- Hung, Hayley, et al.
(författare)
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Toward the next generation of air quality monitoring : Persistent organic pollutants
- 2013
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Ingår i: Atmospheric Environment. - : Elsevier BV. - 1352-2310 .- 1873-2844. ; 80, s. 591-598
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Tidskriftsartikel (refereegranskat)abstract
- Persistent Organic Pollutants (POPs) are global pollutants that can migrate over long distances and bioaccumulate through food webs, posing health risks to wildlife and humans. Multilateral environmental agreements, such as the Stockholm Convention on POPs, were enacted to identify POPs and establish the conditions to control their release, production and use. A Global Monitoring Plan was initiated under the Stockholm Convention calling for POP monitoring in air as a core medium; however long temporal trends (>10 years) of atmospheric POPs are only available at a few selected sites. Spatial coverage of air monitoring for POPs has recently significantly improved with the introduction and advancement of passive air samplers. Here, we review the status of air monitoring and modeling activities and note major uncertainties in data comparability, deficiencies of air monitoring and modeling in urban and alpine areas, and lack of emission inventories for most POPs. A vision for an internationally-integrated strategic monitoring plan is proposed which could provide consistent and comparable monitoring data for POPs supported and supplemented by global and regional transport models. Key recommendations include developing expertise in all aspects of air monitoring to ensure data comparability and consistency; partnering with existing air quality and meteorological networks to leverage synergies; facilitating data sharing with international data archives; and expanding spatial coverage with passive air samplers. Enhancing research on the stability of particle-bound chemicals is needed to assess exposure and deposition in urban areas, and to elucidate long-range transport. Conducting targeted measurement campaigns in specific source areas would enhance regional models which can be extrapolated to similar regions to estimate emissions. Ultimately, reverse-modeling combined with air measurements can be used to derive “emission” as an indicator to assess environmental performance with respect to POPs on the country, region, or global level.
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| 12. |
- MacLeod, Matthew, 1973-, et al.
(författare)
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Computational models to confront the complex pollution footprint of plastic in the environment
- 2023
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Ingår i: Nature Computational Science. - 2662-8457. ; 3:6, s. 486-494
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Tidskriftsartikel (refereegranskat)abstract
- The threat posed by plastic in the environment is poorly characterized due to uncertainties and unknowns about sources, transport, transformation and removal processes, and the properties of the plastic pollution itself. Plastic creates a footprint of particulate pollution with a diversity of composition, size and shape, and a halo of chemicals. In this Perspective, we argue that process-based mass-balance models could provide a platform to synthesize knowledge about plastic pollution as a function of its measurable intrinsic properties.
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| 13. |
- MacLeod, Matthew, 1973-, et al.
(författare)
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The global threat from plastic pollution
- 2021
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 373:6550, s. 61-65
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Tidskriftsartikel (refereegranskat)abstract
- Plastic pollution accumulating in an area of the environment is considered “poorly reversible” if natural mineralization processes occurring there are slow and engineered remediation solutions are improbable. Should negative outcomes in these areas arise as a consequence of plastic pollution, they will be practically irreversible. Potential impacts from poorly reversible plastic pollution include changes to carbon and nutrient cycles; habitat changes within soils, sediments, and aquatic ecosystems; co-occurring biological impacts on endangered or keystone species; ecotoxicity; and related societal impacts. The rational response to the global threat posed by accumulating and poorly reversible plastic pollution is to rapidly reduce plastic emissions through reductions in consumption of virgin plastic materials, along with internationally coordinated strategies for waste management.
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| 14. |
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| 15. |
- Peets, Pilleriin, 1992-, et al.
(författare)
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MS2Tox Machine Learning Tool for Predicting the Ecotoxicity of Unidentified Chemicals in Water by Nontarget LC-HRMS
- 2022
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 56:22, s. 15508-15517
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Tidskriftsartikel (refereegranskat)abstract
- To achieve water quality objectives of the zero pollution action plan in Europe, rapid methods are needed to identify the presence of toxic substances in complex water samples. However, only a small fraction of chemicals detected with nontarget high-resolution mass spectrometry can be identified, and fewer have ecotoxicological data available. We hypothesized that ecotoxicological data could be predicted for unknown molecular features in data-rich high-resolution mass spectrometry (HRMS) spectra, thereby circumventing time-consuming steps of molecular identification and rapidly flagging molecules of potentially high toxicity in complex samples. Here, we present MS2Tox, a machine learning method, to predict the toxicity of unidentified chemicals based on high-resolution accurate mass tandem mass spectra (MS2). The MS2Tox model for fish toxicity was trained and tested on 647 lethal concentration (LC50) values from the CompTox database and validated for 219 chemicals and 420 MS2 spectra from MassBank. The root mean square error (RMSE) of MS2Tox predictions was below 0.89 log-mM, while the experimental repeatability of LC50 values in CompTox was 0.44 log-mM. MS2Tox allowed accurate prediction of fish LC50 values for 22 chemicals detected in water samples, and empirical evidence suggested the right directionality for another 68 chemicals. Moreover, by incorporating structural information, e.g., the presence of carbonyl-benzene, amide moieties, or hydroxyl groups, MS2Tox outperforms baseline models that use only the exact mass or logKOW.
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| 16. |
- Persson, Linn, et al.
(författare)
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Confronting Unknown Planetary Boundary Threats from Chemical Pollution
- 2013
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:22, s. 12619-12622
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Tidskriftsartikel (refereegranskat)abstract
- Rockström et al. proposed a set of planetary boundaries that delimitate a “safe operating space for humanity”. One of the planetary boundaries is determined by “chemical pollution”, however no clear definition was provided. Here, we propose that there is no single chemical pollution planetary boundary, but rather that many planetary boundary issues governed by chemical pollution exist. We identify three conditions that must be simultaneously met for chemical pollution to pose a planetary boundary threat. We then discuss approaches to identify chemicals that could fulfill those conditions, and outline a proactive hazard identification strategy that considers long-range transport and the reversibility of chemical pollution.
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| 17. |
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| 18. |
- Plaza-Hernández, Marta, et al.
(författare)
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Integration of production and use information into an exposure-based screening approach to rank chemicals of emerging Arctic concern for potential to be planetary boundary threats
- 2021
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Ingår i: Emerging Contaminants. - : Elsevier BV. - 2405-6650 .- 2405-6642. ; 7, s. 213-218
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Tidskriftsartikel (refereegranskat)abstract
- Planetary boundaries delimit a ‘safe operating space for humanity’ that should not be overstepped to maintain stable Holocene-like conditions on Earth. Some chemical pollutants have the potential to pose a planetary boundary threat to the functioning of vital Earth system processes as so-called ‘novel entities’. Recently, an exposure-based prioritization scheme was developed that uses model-estimated data on persistence and degree of mobility in air and water to identify and prioritise chemical substances that may be planetary boundary threats. As a case study, chemicals of emerging Arctic concern identified by the Arctic Monitoring and Assessment Programme (AMAP) were used to develop the scheme. The exposure-based prioritization scheme cannot address all scenarios for a chemical to pose an unknown planetary boundary threat, but it does allow for prioritization of chemicals according to environmental fate and exposure profiles. A key limitation of the scheme is that the quantity of chemical potentially released to the environment was not considered in the prioritization. Here, we use data on chemical production and use reported under the European chemicals regulation REACH, and an emission scoring system developed by the European Food Safety Authority (EFSA) to attempt to add information about estimated emissions to the exposure-based prioritization scheme. Using REACH data and the EFSA scoring system, we ranked the AMAP substances according to their potential for environmental release and combined that information with the previously reported exposure-based prioritization that considers persistence and long-range transport potential. Our method successfully assigned ‘high priority’ to known ozone-depleting substances (methyl chloride and dichloromethane) and identified chemicals of concern recently under consideration for nomination as persistent organic pollutants under the Stockholm Convention (octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane). The EFSA scoring system offers a useful starting point that provided useful additional information in the case study for chemicals of emerging Arctic concern, but lack of information to estimate potential releases of chemicals was a major limitation.
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| 19. |
- Rodríguez-Leal, Inés, 1985-, et al.
(författare)
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The applicability domain of EPI Suite™ for screening phytotoxins for potential to contaminate source water for drinking
- 2022
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Ingår i: Environmental Sciences Europe. - : Springer Science and Business Media LLC. - 2190-4707 .- 2190-4715. ; 34
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Tidskriftsartikel (refereegranskat)abstract
- Background: Toxins produced by plants constitute a potential threat to water supplies in Europe, but have not been widely considered in systematic risk assessments. One way to begin to address potential risks of phytotoxins is to conduct screening-level assessments of known phytotoxins for their potential to contaminate source water for drinking due to persistence (P) and mobility (M). Chemical properties relevant for such an assessment (octanol–water partition coefficient KOW and biodegradation half-life) can be estimated from the structure of phytotoxins with quantitative structure–property relationship (QSPR) models found in the United States Environmental Protection Agency’s Estimation Program Interface (EPI Suite™) software, but predictions must be considered critically since these models have been developed using data for anthropogenic chemicals and many phytotoxins could lie outside their applicability domain.Results: We analyzed two EPI Suite™ models—KOWWIN and BIOWIN5—by evaluating the quality of property predictions for their validation sets as a function of Euclidean distances dE to the centroid of descriptor space of the models’ training sets. We identified model-specific applicability domain boundaries as local maxima in plots of the difference between root mean square error (∆RMSE) of modeled property values of validation set compounds within and outside applicability domain boundaries defined by a continuum of possible boundaries. And, we also evaluated four generic boundaries that have been suggested in literature. The ∆RMSE between validation set compounds outside and inside applicability domain boundaries had positive values for all but one of the possible boundaries we considered, indicating that properties of chemicals with dE inside the boundaries were better predicted. With our proposed model-specific boundaries, 21% of 1586 phytotoxins produced by plants found in Switzerland were out of domain of KOWWIN, and 46% of were out of domain of BIOWIN5.Conclusions: Estimates of Log KOW and biodegradation half-life of phytotoxins that lie outside the domain of applicability of the QSPR models should be viewed as extrapolations that are subject to unquantified and potentially large errors. Phytotoxins outside the domain of applicability of QSPR models should be prioritized for property measurements as a basis to expand the training sets of QSPR models and to support hazard identification for better management of drinking water quality in Europe.
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| 20. |
- Roth, Sabrina K., et al.
(författare)
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Scenario-based modelling of changes in chemical intake fraction in Sweden and the Baltic Sea under global change
- 2023
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Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 888
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Tidskriftsartikel (refereegranskat)abstract
- The climate in Europe is warming twice as fast as it is across the rest of the globe, and in Sweden annual mean tempera-tures are forecast to increase by up to 3-6 & DEG;C by 2100, with increasing frequency and magnitude of floods, heatwaves, and other extreme weather. These climate change-related environmental factors and the response of humans at the individual and collective level will affect the mobilization and transport of and human exposure to chemical pollutants in the envi-ronment. We conducted a literature review of possible future impacts of global change in response to a changing climate on chemical pollutants in the environment and human exposure, with a focus on drivers of change in exposure of the Swedish population to chemicals in the indoor and outdoor environment. Based on the literature review, we formulated three alternative exposure scenarios that are inspired by three of the shared socioeconomic pathways (SSPs). We then con-ducted scenario-based exposure modelling of the >3000 organic chemicals in the USEtox (R) 2.0 chemical library, and fur-ther selected three chemicals (terbuthylazine, benzo[a]pyrene, PCB-155) from the USEtox library that are archetypical pollutants of drinking water and food as illustrative examples. We focus our modelling on changes in the population intake fraction of chemicals, which is calculated as the fraction of a chemical emitted to the environment that is ingested via food uptake or inhaled by the Swedish population. Our results demonstrate that changes of intake fractions of chemicals are possible by up to twofold increases or decreases under different development scenarios. Changes in intake fraction in the most optimistic SSP1 scenario are mostly attributable to a shift by the population towards a more plant-based diet, while changes in the pessimistic SSP5 scenario are driven by environmental changes such as rain fall and runoff rates.
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| 21. |
- Salvito, Daniel, et al.
(författare)
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The Path to UVCB Ecological Risk Assessment : Grappling with Substance Characterization
- 2022
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 41:11, s. 2649-2657
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Tidskriftsartikel (refereegranskat)abstract
- Substances of unknown or variable composition, complex reaction products, and biological materials (UVCBs) pose a unique challenge to regulators and to product registrants, who are required to characterize their fate, exposure, hazard, and potential risks to human health and the environment. To address these challenges and ensure an efficient and fit-for-purpose process, it is proposed that the ecological risks of UVCBs be assessed following a tiered strategy. The development of this approach required exploring how substance composition ties into hazard and exposure information and determining the extent to which a UVCB needs to be characterized to ensure a robust risk assessment. The present study highlights the key aspects of this new method. It presents how a tiered substance characterization approach can be integrated into broader UVCB risk-assessment schemes to encourage an examination of data needs before a full substance characterization is performed. The first tier of the characterization process, Tier 0, is a fundamental step that includes data from basic, lower-resolution compositional analyses. Tier 0 assessments can be used to inform hazard and exposure for any substance of interest. The need for more sophisticated, higher-tier characterization is determined by the level of uncertainty of the risk assessment. The next step will integrate a tiered exposure assessment into the characterization scheme featured in the present study, to create a more complete risk-assessment framework. Environ Toxicol Chem 2022;41:2649–2657. © 2022 Her Majesty the Queen in Right of Canada, Health and Environmental Sciences Institute and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.
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| 22. |
- Sepman, Helen, et al.
(författare)
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Bypassing the Identification : MS2Quant for Concentration Estimations of Chemicals Detected with Nontarget LC-HRMS from MS2 Data
- 2023
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Ingår i: Analytical Chemistry. - 0003-2700 .- 1520-6882. ; 95:33, s. 12329-12338
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Tidskriftsartikel (refereegranskat)abstract
- Nontarget analysis by liquid chromatography-high-resolutionmass spectrometry (LC-HRMS) is now widely used to detect pollutants in the environment. Shifting away from targeted methods has led to detection of previously unseen chemicals, and assessing the risk posed by these newly detected chemicals is an important challenge. Assessing exposure and toxicity of chemicals detected with nontarget HRMS is highly dependent on the knowledge of the structure of the chemical. However, the majority of features detected in nontarget screening remain unidentified and therefore the risk assessment with conventional tools is hampered. Here, we developed MS2Quant, a machine learning model that enables prediction of concentration from fragmentation(MS2) spectra of detected, but unidentified chemicals. MS2Quant is an xgbTree algorithm-based regression model developed using ionization efficiency data for 1191 unique chemicals that spans 8 orders of magnitude. The ionization efficiency values are predicted from structural fingerprints that can be computed from the SMILES notation of the identified chemicals or from MS2 spectra of unidentified chemicals using SIRIUS+CSI: FingerID software. The root mean square errors of the training and test sets were 0.55(3.5x) and 0.80 (6.3x) log-units, respectively. In comparison, ionization efficiency prediction approaches that depend on assigning an unequivocal structure typically yield errors from 2x to 6x. The MS2Quant quantification model was validated on a set of 39 environmental pollutants and resulted in a mean prediction error of 7.4x, ageometric mean of 4.5x, and a median of 4.0x. For comparison, a model based on PaDEL descriptors that depends on unequivocal structural assignment was developed using the same dataset. The latter approach yielded a comparable mean prediction error of 9.5x, a geometricmean of 5.6x, and a median of 5.2x on the validation set chemicals when the top structural assignment was used as input. This confirms that MS2Quant enables to extract exposure information for unidentified chemicals which, although detected, have thus far been disregarded due to lack of accurate tools for quantification. TheMS2Quant model is available as an R-package in GitHub for improving discovery and monitoring of potentially hazardous environmental pollutants with nontarget screening.
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| 23. |
- Sühring, Roxana, et al.
(författare)
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Fate-directed risk assessment of chemical mixtures : a case study for cedarwood essential oil
- 2022
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Ingår i: Environmental Science. - : Royal Society of Chemistry (RSC). - 2050-7887 .- 2050-7895. ; 24:8, s. 1133-1143
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Tidskriftsartikel (refereegranskat)abstract
- The environmental risk assessment of UVCBs (i.e., substances of unknown or variable composition, complex reaction products, or biological materials) is challenging due to their inherent complexity. A particular problem is that UVCBs can contain constituents with unidentified chemical structures and/or have variable composition of constituents from batch to batch. Moreover, the composition of a UVCB in the environment is not the same as that of the UVCB in a product, meaning that a risk assessment based on environmental exposure to the UVCB in a product does not represent the actual environmental risk. Here we propose an in silico fate-directed risk assessment framework for UVCBs using cedarwood oil as a case study. The framework uses Monte Carlo simulations and the mass-balance models SimpleTreat and RAIDAR to provide quantitative information on whether unidentified constituents within the physical–chemical property space of a UVCB can be the decisive factor for the environmental risk of the entire UVCB. Thereby the framework provides a robust decision tool to evaluate if a UVCB risk assessment requires additional tests or if the data on known constituents is representative for the risk of the entire UVCB. In the case of cedarwood oil, it could be shown that a risk assessment based on the known constituents (representing around 70% of the overall UVCB by weight) is representative for the environmental risk of the entire UVCB – reducing the need for additional testing and test animals.
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| 24. |
- Zou, Hongyan, et al.
(författare)
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Evaluation of the potential of benchmarking to facilitate the measurement of chemical persistence in lakes
- 2014
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 95, s. 301-309
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Tidskriftsartikel (refereegranskat)abstract
- The persistence of chemicals in the environment is rarely measured in the field due to a paucity of suitable methods. Here we explore the potential of chemical benchmarking to facilitate the measurement of persistence in lake systems using a multimedia chemical fate model. The model results show that persistence in a lake can be assessed by quantifying the ratio of test chemical and benchmark chemical at as few as two locations: the point of emission and the outlet of the lake. Appropriate selection of benchmark chemicals also allows pseudo-first-order rate constants for physical removal processes such as volatilization and sediment burial to be quantified. We use the model to explore how the maximum persistence that can be measured in a particular lake depends on the partitioning properties of the test chemical of interest and the characteristics of the lake. Our model experiments demonstrate that combining benchmarking techniques with good experimental design and sensitive environmental analytical chemistry may open new opportunities for quantifying chemical persistence, particularly for relatively slowly degradable chemicals for which current methods do not perform well.
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