| 1. |
- Rydberg, Tomas, 1962, et al.
(författare)
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Estimating the environmental risk of the societal stock of additives in plastics by a chemical footprint approach
- 2015
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Ingår i: SETAC Europe 25th Annual Meeting.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Environmental risk posed by additives in products in the technosphere in general and in consumer products in particular, is an important issue that has been, so far, investigated to a relatively limited extent. Previous estimates of the national stock and emissions are available on national scale [1,2,3] but the challenge has remained to understand how important or significant these stocks and emissions are from a risk perspective. The research presented here approaches the challenge by assigning risk characterisation scores to the additives and comparing the outcome with corresponding risk characterisation for biocides. We used the previous estimates om stock and emissions of plastic additives. Data for use of biocides were extracted from the Swedish Chemicals Agency The risk characterisation was carried out by applying USETox characterisation factors (CF), The amount of each substance, has been multiplied with its corresponding CF from USETox. These substance specific risk scores were then added to the overall risk score. It is clear that there are many uncertainties in the calculations. For example the emission calculations in the overall society example seem unreasonably high, in the order of 2 % annually of the total stock. In other work applying an advanced emission model to a limited sample of products, the emission rate is in the order of 0.02 % annually. This indicates that the overall society-wide emissions could be in the order of 500 tons rather than 47000 tons. For the risk scores, the uncertainty is even bigger, as the uncertainty of the CFs themselves come into play, as well as the incomplete availability of CFs. The total risk score for the National total use of biocides is 9.3E+09 CTU. This is to be compared with the risk scores as calculated for the additives, which is 1.3E+12 CTU for the total stock of additives and 3E+10 CTU for the emissions, or possible a factor 100 lower if assuming a similar overestimation as for emissions. The results are very sensitive to the identified uncertainties, and also to lack of CFs for possibly important substances, both among the additives and the biocides.
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| 2. |
- Grönholdt Palm, Julia, et al.
(författare)
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Strategies to deal with information of different reliability exemplified by the use of QSARs to fill the algae data gaps in LCIAs of plastic additives
- 2015
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Ingår i: SETAC Europe 25th Annual Meeting.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Data gaps are problematic when screening fordangerous substances or in impact assessments where several chemicals are considered for evaluation. Lacking testing information can be replaced by non-testing information such as Quantitative Structure Activity Relationships (QSARs), but even though this latter information comes with lower reliability, this is seldom taken into account in theforthcoming assessments. The difficulty to meet standards for best information calls for strategies to handle data gaps which take varying reliability in information into account. Using safety factors when reliability is low can be problematic since this result in more conservative evaluations of substances for which information is of lowreliability and an unknown level of risk aversion in the assessment. An alternative is to reflect lower reliability using probability distributions representing the expected error in the information and propagate this uncertainty in the forthcoming assessments using Monte Carlo analysis.It is even possible to let the error to expect from QSARs depend to what extent a substance falls inside the models domain of applicability.QSARs cannot fill all gaps in data. Default values can be used instead of leaving substances out of assessments, but if so, these should reflect lowreliability as well. We demonstrate the practical implications of four strategies to handle varying reliability in information on algal toxicity in a Life Cycle Impact Assessment on 159 plastic additives of concernusing emissions from societal plastic materials in Sweden. A review concluded that a small amount of these substances had toxicity data for algae Pseudokirchneriella subcapitata. A QSAR was constructed which provided non-testing algal information of substances inside and on theborder of the models domain of applicability evaluated by PmodXPS.Substances with neither testing nor non-testing information were assigned default values. Screening based on characterization factors resulted in different rankings of substances when changing the level of cautiousness. The different strategies to handle varying reliability ininformation do more or less open up for quantifying uncertainty in Life Cycle Impact Assessments.
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| 3. |
- Gustavsson, Nicklas, et al.
(författare)
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Geotextiles and microplastics in Sweden - an assessment
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In the EU, there are ongoing efforts that aim to reduce the presence of microplastic release to the environment. In addition to the proposed restriction under REACH of intentionally added microplastics in products, the strategy also includes measures directed towards the unintentional release of microplastics. In a public consultation, the European Commission included questions related to geotextiles and their release of microplastics. In order to map the situation in Sweden and improve knowledge on geotextiles, the Swedish Environmental protection Agency (Swedish EPA) has commissioned Ramboll to provide this information, to assess geotextiles as a source of microplastics in Sweden and to suggest further studies. The information will also provide input to the ongoing governmental assignment the Swedish EPA has on mapping and monitoring plastic flows towards the transition to a circular economy.Geotextiles are synthetic or natural polymeric textile materials used in contact with soil and/or other materials in geotechnical and civil engineering applications. Its use in Europe began in the 1950’s but accelerated during the 1980’s and -90’s. In Sweden, the use of geotextiles was approximately 14900 tonnes in 2021 and its major use was for separation and filtration applications. A vast majority (>95%) of the geotextiles used are made of nonwoven polypropylene (PP). Geotextiles are classified as construction products and fall under Regulation (EU) No 305/2011. To be placed on the EU market, geotextiles must conform with technical criteria, including durability requirements, in harmonised standards and be CE labelled. Since the service life of geotextiles in many applications is expected to be 100 years, not much of the geotextiles used to date have been recovered or treated as waste and very little experience of this therefore exists. Used geotextiles are sorted as either plastic waste or in fractions for combustible waste. Recycled content in geotextile manufacturing is very limited, partly due to limitations of use laid down in the harmonised standards.There is not much research on geotextiles and their release of microplastics. A previous estimation of global geotextile release of microplastics appears to have used flawed assumptions and exaggerates the release. It is known that geotextiles are exposed to several environmental factors that all can contribute to their degradation, of these, exposure to UV-light is arguably the most important. In this study, two cases are identified that could potentially lead to microplastic release. Hydraulic applications, where geotextiles are in contact with water and exposed to several degradation factors, is a higher risk application. The other identified risk is the use of geotextiles for soil applications that are not installed according to manufacturer’s instructions and left exposed to UV and other degradation factors.In this report, it is estimated that geotextiles currently release 2-32 tonnes of microplastics per year in Sweden. The estimation is based on several assumptions regarding release of microplastics due to lack of information. As a comparison, this is similar to other sources of unintentionally released microplastics such as fishing gear (4–46 tonnes/year) or industrial laundry (2–115 tonnes/year). The estimation also shows that the accumulation and ageing of geotextiles may cause this to become a major source of microplastics in the future. In the worst-case scenario, approximately up to 800 tonnes per year would be released by 2050 and in 100 years from now, the amount would be closer to 21 000 tonnes. The calculation includes several limitations and uncertainties and should be seen as an indication until further research is performed.Ramboll proposes to advance the understanding of microplastics release from geotextiles by performing actual measurements, such as leaching tests and to investigate whether also new unused geotextiles release fibres. It is equally important to develop an understanding of the relationship between degradation and microplastics, i.e., what kind of degradation (measured by e.g., strength retention tests) is required to cause microplastics emissions and at what rate.
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| 4. |
- Holmquist, Hanna, 1982, et al.
(författare)
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The potential to use QSAR to populate ecotoxicity characterisation factors for simplified LCIA and chemical prioritisation
- 2018
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Ingår i: International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 1614-7502 .- 0948-3349. ; 23:11, s. 2208-2216
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Today’s chemical society use and emit an enormous number of different, potentially ecotoxic, chemicals to the environment. The vast majority of substances do not have characterisation factors describing their ecotoxicity potential. A first stage, high throughput, screening tool is needed for prioritisation of which substances need further measures. Methods: USEtox characterisation factors were calculated in this work based on data generated by quantitative structure-activity relationship (QSAR) models to expand substance coverage where characterisation factors were missing. Existing QSAR models for physico-chemical data and ecotoxicity were used, and to further fill data gaps, an algae QSAR model was developed. The existing USEtox characterisation factors were used as reference to evaluate the impact from the use of QSARs to generate input data to USEtox, with focus on ecotoxicity data. An inventory of chemicals that make up the Swedish societal stock of plastic additives, and their associated predicted emissions, was used as a case study to rank chemicals according to their ecotoxicity potential. Results and discussion: For the 210 chemicals in the inventory, only 41 had characterisation factors in the USEtox database. With the use of QSAR generated substance data, an additional 89 characterisation factors could be calculated, substantially improving substance coverage in the ranking. The choice of QSAR model was shown to be important for the reliability of the results, but also with the best correlated model results, the discrepancies between characterisation factors based on estimated data and experimental data were very large. Conclusions: The use of QSAR estimated data as basis for calculation of characterisation factors, and the further use of those factors for ranking based on ecotoxicity potential, was assessed as a feasible way to gather substance data for large datasets. However, further research and development of the guidance on how to make use of estimated data is needed to achieve improvement of the accuracy of the results.
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