Priority assessment of toxic substances in life cycle assessment. Part I: calculation of toxicity potentials for 181 substances with the nested multi-media fate, exposure and effects model USES-LCA

Removal of toilet paper fibers from residential wastewater: a life cycle assessment

Toilet paper has been reported as one of the major insoluble pollutant components in the influent of wastewater treatment plants. Toilet paper fibers contribute to a large production of sewage sludge, resulting in a high treatment cost and high energy consumption. To find energy-efficient, cost-effective, and environment-friendly technologies for fiber removal and resource recovery from wastewater, a life-cycle assessment (LCA) was performed to analyze the wastewater treatment processes, including a sieving process for removing and recovering suspended solids before the biodegradation units. Based on the LCA results, it was estimated that the sieve screening process saved 8.57% of energy consumption. The construction phase of sieving consumed 1.31% energy cost compared with the operation phase. Environmental impact analysis showed that sieving reduced the impacts of climate change, human toxicity, fossil depletion, and particulate matter formation, which reduced the total normalized environmental impacts by 9.46%. The life-cycle analysis of the removal of toilet paper fibers from wastewater revealed the need to use more efficient methods to enhance the recovery of cellulose fibers.

Comparative assessment of environmental impacts, mitigation potentials, and economic benefits of rain-fed and irrigated apple production systems on China's Loess Plateau

Although the repaid development of China's apple industry heavily depends on excessive fertilizer-water-pesticide (FWP) inputs, little information is available that systematically evaluates environmental impacts, mitigation potential, and economical benefits of apple production systems in China. In this study, life cycle assessment (LCA) was conducted to elucidate environmental risks and mitigation potentials of rain-fed and irrigated apple production systems on China's Loess Plateau based on survey data from 847 farmers, and economic benefits were analyzed simultaneously. Results showed that irrigated orchards caused more severe environmental risks associated with energy depletion (ED), global warming potential (GWP) and acidification potential (AP) than those in rain-fed orchards, whereas an opposite was true for eutrophication potential (EP), human toxicity potential (HTP), aquatic toxicity potential (ATP) and soil toxicity potential (STP). ED and GWP occurred primarily in the agricultural material stage, while AP, EP, HTP, ATP, and STP occurred mostly in the orchard management stage. Optimized FWP management can markedly mitigate environmental impacts in both irrigated and rain-fed orchard systems. Synthetic fertilizer, because of production and field-associated emissions, was the greatest contributor to environmental impacts of an apple production system. An environmental pollution index (EPI) that integrated environmental categories was highest in conventional irrigated orchards (0.946), followed by conventional rainfed orchards (0.857), and optimized irrigated orchards (0.459), and the lowest EPI was in optimized rainfed orchards (0.389). Economic analysis revealed that the benefits of rainfed orchards were higher than those of irrigated orchards because of higher apple prices and lower labor costs. Optimized FWP management sharply decreased input costs, thereby substantially increasing net income in irrigated and rain-fed apple orchards. Overall, severe environmental risk and large mitigation potential co-exist in rain-fed and irrigated apple orchards on China's Loess Plateau. Integrated soil-crop-market management potentially exhibited considerable environmental and economic advantages, thereby efficiently developing high-quality apple production.

An integrated framework for industrial symbiosis performance evaluation in an energy-intensive industrial park in China

Industrial symbiosis (IS) is an important tool to achieve green development for industrial parks. It is necessary to evaluate the IS performance for monitoring and managing the development of IS system. This study proposed an integrated framework to assess the IS performance based on the energy-intensive industrial park. Firstly, we established a Conceptual model of symbiotic coupling of three industries (iron and steel, thermal power, and cement). Then, the conceptual model was applied to extend the existing IS system in the energy-intensive industrial park. Finally, the IS performance of the extended IS system was evaluated. We verified this framework in Red flag cannel park (RFCP). The IS performance assessment in RFCP found that the existing IS activities produced significant multiple benefits and environmental impact reduction. For example, the existing IS activities produced 970.20 kt of low-carbon benefits, which accounted for 19% of the CO₂ emissions in RFCP. However, after extending the existing symbiotic system combined with the conceptual model proposed in this study, we found that there still was a large amount of symbiotic potential (the reuse of waste heat, BF slag, gypsum) waiting to be developed in RFCP. In addition, we also found that the resilience of existing IS network in RFCP was weak and need to be further perfected. In general, in the further development and perfection of IS system in RFCP, the manager should not only focus on the development of IS activities among energy-intensive enterprises but also strive to foster more influential enterprises to enhance the anti-risk ability of IS network. The result indicates the integrated framework can provide support for the development and perfection of IS system in energy-intensive industrial parks.

Relevance of Impact Categories and Applicability of Life Cycle Impact Assessment Methods from an Automotive Industry Perspective

Climate change impacts have been extensively addressed in academia, politics and industry for decades. However, particularly within the scientific community, the importance of considering further impact categories to ensure holistic environmental assessment and avoid burden shifting is strongly emphasized. Since considering all impact categories might become overwhelming for industry, a prioritization approach can support practitioners to focus their efforts on the most relevant impacts. Therefore, within this paper, an approach for the identification of relevant impact categories is developed for the automotive sector together with Volkswagen AG. The evaluation is conducted using a criteria set including criteria groups “relevance for automotive sector” and “relevance for stakeholders”. For the impact categories identified as relevant, an evaluation of LCIA methods is conducted considering the methodologies CML and ReCiPe 2016 and the methods recommended by PEF. The results demonstrate that climate change is by far the most relevant impact category followed by resource use, human toxicity and ecotoxicity from both automotive and stakeholder perspective. Based on the evaluation of the LCIA methods, a combination of different methods can be recommended. This work provides guidance for the automotive sector to prioritize its focus on the most relevant impact categories and to select applicable LCIA methods for their quantification.

Sustainability Assessment of Family Agricultural Properties: The Importance of Homeopathy

Family farming is a lifestyle and agricultural base that has ensured food for the world’s growing population in addition to the family’s own subsistence. However, the intensification of production processes to primarily generate exportable surpluses is based on the constant input of industrial inputs of low local socioeconomic viability. This study aims to evaluate the sustainability of family farms and their impact on the adoption of homeopathy instead of traditional/conventional intensification techniques. The study was conducted at six family farms located in the Serrana Mesoregion, Santa Catarina, Brazil, and include farms were classified according to the management and representativeness of their agricultural activity, i.e., conventional grains-cattle, milk-grains, grains and diversified, and according to their ecological basis, i.e., agroecological and organic. To discuss the sustainability of the family farms that were evaluated, the of metrics emergy synthesis, ecotoxicity potential and socioeconomic indicators are used. The results indicate that conventional diversified property has the best overall performance with regard to sustainability, including emergy yield ratio (EYR 1.88), emergy investment ratio (EIR 1.13), return on assets (1.22), hourly income of work (36.6 BRL/h) and income sufficiency (3.3). Agroecological and organic properties have better performance in renewability (76% and 75%), environmental load (ELR = 0.32 and 0.34), sustainability (ESI = 4.78 and 3.5) and potential ecotoxicity (1.736 and 1.579 kg 1.4 DCB-eq/ha). The contribution of homeopathy in an alternative scenario results in a 19% reduction in nonrenewable flows in conventional management properties and a decrease of up to 91% in ecotoxicity in grain + cattle properties. Using homeopathy, the return on assets and profit margin can be increased by up to 43% and income per hour of work and income sufficiency can be increased by 20% and 16%, respectively. This study contributes to discussions about the importance of using homeopathic therapies as a viable strategy that can be used in strategic public policy plans to improve the sustainability of family farms.

Environmental Impact Analysis of Portland Cement (CEM1) Using the Midpoint Method

The cement industry confronts significant challenges in raw materials, energy demands, and CO2 emissions reduction, which are global and local environmental concerns. Life cycle assessment (LCA) has been used in many studies to assess the environmental impact of cement production and investigate ways to improve environmental performance. This study aims to analyse the environmental impact of Portland cement (CEM I) on the South African cement industry using the life cycle impact assessment (LCIA), based on the Recipe 2016 v 1.04 midpoint method. The study was conducted using data modeled after the South African cement plant, considered a cradle-to-gate system boundary, starting from the extraction of the raw material to the cement production process that produces cement as the main product. The data were obtained from the Ecoinvent database v3.7.1, integrated with SimaPro 9.1.1. software, used to assess the impact categories. For simplicity, the study merged the entire production process into five processes, i.e., raw materials usage, fuel consumption, clinker production, transportation and electricity. The impact categories of the five production stages were assessed using the LCA methodology. The impact categories investigated were classified into three categories: atmospheric, resource depletion and toxicity categories. According to the results, clinker production and electricity usage stages contribute the most to atmospheric impact (global warming, which causes climatic change due to high CO2 emissions), followed by raw materials and fuel consumption, contributing to the toxicity and resource depletion impact category. These stages contribute more than 76% of CO2 eq. and 93% of CFC-11 eq. In the midpoint method, CO2 is the most significant pollutant released. Therefore, replacing fossil fuels with alternative fuels can reduce fossil fuel use and the atmospheric impact of cement kilns.

Uncovering the characteristics of air pollutants emission in industrial parks and analyzing emission reduction potential: case studies in Henan, China

Industrial parks contribute greatly to China’s economic development while emitting huge air pollutants. It is necessary to study the characteristics of air pollutant emissions in industrial parks. In this study, emission inventories for 11 industrial parks were established. Meanwhile, the source emission and spatial distribution characteristics of the industrial park were analyzed. The cluster analysis was used to classify these parks into “4Hs”, “Mixed” and “4Ls” parks. “4Hs”, “Mixed” and “4Ls” represent that the levels of energy intensity, economic proportion of energy-intensive industries, coal proportion and pollution performance value are high, medium and low in turn. Then three emission reduction measures were set up to estimate the emission reduction potential and environmental impacts. The results show that: (1) the emissions of SO₂, NO_x, CO, PM₁₀, PM_2.5, VOCs and NH₃ of 11 industrial parks in 2017 were 11.2, 23.1, 30.8, 8.3, 3.5, 5.1, and 1.1 kt, respectively. (2) Power plants were the largest source of SO₂ and NO_x emissions, and industrial processes were the largest emission source of CO, PM₁₀, PM_2.5, VOCs and NH₃. (3) “4Hs” parks with traditional energy-intensive industries as the leading industries should be the emphasis of air pollutant emission reduction. (4) Through the optimal emission reduction measures, SO₂, NO_x, PM₁₀, PM_2.5 and VOCs were reduced by 81, 46, 51, 46 and 77%, respectively. Environmental impact reductions include 1.6 kt SO₂eq acidified gas emissions, 1.4 kt PO₄³⁻eq eutrophication substances, 4.2 kt PM₁₀eq atmospheric particulate emissions, 7.0 kt 1,4-DCEeq human toxic substances, and 5.2 kt PM_2.5 eq breathing Inorganic. This study is helpful to understand the characteristics of air pollutants emissions in industrial parks and promotes the proposal and implementation of air pollutant emissions reduction strategies.

Fertilizer and pesticide reduction in cherry tomato production to achieve multiple environmental benefits in Guangxi, China

Cherry tomatoes, as a highly profitable vegetable, consume a substantial amount of fertilizer and pesticide compared with other staple crops, which leads to remarkably negative environmental impacts. The optimization of these agricultural inputs to mitigate these environmental burdens and improve cherry tomato yield has drawn little attention. This study used life cycle assessment (LCA) combined with a field investigation to analyze the environmental benefits under optimized fertilizer and pesticide inputs (i.e., reduction of 24.7% nitrogen, 35.6% phosphorus pentoxide, 18.8% potassium oxide, 17.1% organic fertilizer, and 30.9% pesticides) compared to traditional farmer inputs. Results showed that: (1) compared to traditional farmer management, optimized inputs reduced the energy depletion by 24.7%, water depletion by 6.4%, global warming by 28.8%, acidification by 23.7%, aquatic eutrophication by 34.2%, human toxicity by 34.8%, aquatic eco-toxicity by 34.8%, and soil eco-toxicity by 26.7%, respectively; (2) among them, aquatic eco-toxicity and aquatic eutrophication were the major environmental impacts in cherry tomato production and were mainly attributed to chlorothalonil and phosphate fertilizer use, respectively; and (3) optimized inputs decreased the total environmental index and environmental damage cost by 33.8% and 28.1%, respectively, without compromising the yield. These findings provide insight into optimizing fertilizer and pesticide usage to alleviate multiple environmental impacts while maintaining cherry tomato yield and improving economic benefits. Further studies should focus mainly on less harmful pesticide utilization and phosphate use efficiency improvement, which may achieve vegetable production system sustainability in China and also provide a reference value for vegetable production systems in the Global South.

Life Cycle Assessment of Spinach Produced in Central and Southern Italy

Environmental sustainability continues to attract global interest, especially due to the issue of climate change. The agri-food sector is considered a major contributor to climate change as processes and activities within the sector can negatively impact the environment. The recent changing dietary pattern towards increased vegetable consumption implies a consequent increase in production to meet demand. This study assessed the environmental performance of 1 kg of spinach/FU (Functional Unit) cultivated by different producers in Italy under integrated and organic farming systems. The life cycle assessment was used following the CML_IA impact assessment method. The data used was mainly primary, related to 2019/2020 (harvest period), and representative of the cultivation systems of central and southern Italy. From the results obtained, impact scores for central Italy were higher (e.g., for global warming 0.56 and 0.47 kg CO2 eq. for central and southern respectively). There was high variability among the scores obtained. However, no statistically significant differences were observed at a confidence level of 95% (p < 0.05). Integrated farming was also more impacting than organic for most categories (e.g., for global warming 0.20 kg CO2 eq. for integrated and 0.075 kg CO2 eq. for organic) in Cerignola, Puglia region. Emissions from fertilizer, pesticide, tillage, and combine harvesting were major contributors to impact shares. The results of this study will be helpful to ensure sustainable spinach production and consumption.

Life Cycle Assessment of Protected Strawberry Productions in Central Italy

Agricultural activities in Europe cover half of the total area of the continent and are simultaneously a cause of environmental impact and victims of the same impact. Horticultural or fruit crops are considered highly intensive and often employ many crop inputs such as fertilizers, pesticides, and various materials. Strawberry falls into this group, and it has grown in acreage and production more than others globally. The aim of this study is to compare the environmental impact of two strawberry cultivation systems in central Italy, a mulched soil tunnel and a soilless tunnel system. The method used to assess the impact is LCA, widely applied in agriculture and supported by international standards. The data used are mainly primary, related to 2018, and representative of the cultivation systems of central Italy. For impact assessment, the method selected was the CML_IA baseline version. From the results obtained, the two systems show a similar impact per kg of strawberries produced (e.g., for global warming: 0.785 kg CO2 eq for soilless, 0.778 kg CO2 eq for mulched soil tunnel). Reduced differences can be observed for the use of crop inputs (greater for the tunnel) and the use of materials and technology (greater for soilless). The mitigation measures considered concern the replacement of the packaging (excluding plastic) and the growing medium of the soilless using perlite and compost from insect breeding.

Comparing Life Cycle Assessment (LCA) of Salmonid Aquaculture Production Systems: Status and Perspectives

Aquaculture is the fastest growing food sector worldwide, mostly driven by a steadily increasing protein demand. In response to growing ecological concerns, life cycle assessment (LCA) emerged as a key environmental tool to measure the impacts of various production systems, including aquaculture. In this review, we focused on farmed salmonids to perform an in-depth analysis, investigating methodologies and comparing results of LCA studies of this finfish family in relation to species and production technologies. Identifying the environmental strengths and weaknesses of salmonid production technologies is central to ensure that industrial actors and policymakers make informed choices to take the production of this important marine livestock to a more sustainable path. Three critical aspects of salmonid LCAs were studied based on 24 articles and reports: (1) Methodological application, (2) construction of inventories, and (3) comparison of production technologies across studies. Our first assessment provides an overview and compares important methodological choices. The second analysis maps the main foreground and background data sources, as well as the state of process inclusion and exclusion. In the third section, a first attempt to compare life cycle impact assessment (LCIA) and feed conversion ratio (FCR) data across production technologies was conducted using a single factor statistical protocol. Overall, findings suggested a lack of methodological completeness and reporting in the literature and demonstrated that inventories suffered from incomplete description and partial disclosure. Our attempt to compare LCA results across studies was challenging due to confounding factors and poor data availability, but useful as a first step in highlighting the importance of production technology for salmonids. In groups where the data was robust enough for statistical comparison, both differences and mean equalities were identified, allowing ranking of technology clusters based on their average scores. We statistically demonstrated that sea-based systems outperform land-based technology in terms of energy demand and that sea-based systems have a generally higher FCR than land-based ones. Cross-study analytics also strongly suggest that open systems generate on average more eutrophying emissions than closed designs. We further discuss how to overcome bottlenecks currently hampering such LCA meta-analysis. Arguments are made in favor of further developing cross-study LCA analysis, particularly by increasing the number of salmonid LCA available (to improve sample sizes) and by reforming in-depth LCA practices to enable full reproducibility and greater access to inventory data.

PestLCI 2.0 sensitivity to soil variations for the evaluation of pesticide distribution in Life Cycle Assessment studies

Pesticides are commonly applied in conventional agricultural systems, but they can lead to serious environmental contamination. The calculation of on-field pesticide emissions in Life Cycle Assessment (LCA) studies is challenging, because of the difficulty in the calculation of the fate of pesticides and, therefore, several literature approaches based on different dispersion models have been developed. PestLCI 2.0 model can provide simultaneous assessment of the emission fractions of a pesticide to air, surface water and groundwater based on many parameters. The goal of this study is to exploit the extent of PestLCI 2.0 sensitivity to soil variations, with the ultimate goal of increasing the robustness of the modelling of pesticide emissions in LCA studies. The model was applied to maize cultivation in an experimental farm in Northern Italy, considering three tests, which evaluated the distribution of pesticides among environmental compartments obtained considering different soil types. Results show that small variations in soil characteristics lead to great variation of PestLCI 2.0, with a significance that depends on the type of environmental compartment. The compartment most affected by soil variations was groundwater, whereas surface waters were dominated by meteorological conditions, pesticides' physical and chemical properties and wind drift, which are independent from soil characteristics. Therefore, the use of specific soil data in PestLCI 2.0 results in the availability of a comprehensive set of emission data in the different compartments, which represents a relevant input for the inventory phase of LCA studies and can increase their robustness. Nevertheless, PestLCI 2.0 requires a great effort for the data collection and a specific expertise in soil science for interpreting the results. Moreover, characterization factors for pesticide groundwater emissions should be developed, in order to exploit these detailed results in the impact assessment phase, Finally, the study provides further insights into future improvement of PestLCI 2.0.

Modeling pharmaceutical emissions and their toxicity-related effects in life cycle assessment (LCA): A review

Over the last few decades, worldwide detection of active pharmaceutical ingredients (APIs) in aquatic environments and the associated toxicological effects on wildlife and human health have become a matter of public and scientific debate. While life cycle assessment (LCA) and life cycle impact assessment (LCIA) models are increasingly used to assess the potential eco- and human-toxicological effects of chemical emissions, few studies have looked into the issue of modeling pharmaceutical emissions specifically and their toxicity-related effects in an LCA context. This paper reviews the state of the art to inventory and characterize API emissions in LCA with the goal to identify relevant gaps and challenges. A search for 208 environmentally relevant APIs in 2 life cycle inventory (LCI) databases revealed a meager representation of this group of chemicals. Similarly, the LCIA model USEtox was found to include characterization factors (CFs) for less than 60 APIs. First approaches to model API emissions in LCA were identified on the basis of an examination of 40 LCA case studies in the pharmaceutical sector and in the field of wastewater treatment. Moreover, CFs for 79 additional APIs, expressing their ecotoxicity and/or human toxicity potential, were gathered from literature. An analysis of the variability of API-CFs in different LCIA models showed a variation of about 2-3 orders of magnitude. Based on the review results, 3 main gaps in the modeling and characterization of API emissions in an LCA context were identified: (1) incomplete modeling of API flows and API emissions along the life cycle of human pharmaceuticals, especially during their use and end-of-life phase, (2) limited API coverage in existing LCIA toxicity models, and (3) missing pharma-specific impact pathways (e.g., endocrine disruption and antibiotic resistance) in existing LCIA models. Recommendations to tackle these gaps are provided, and priority action steps are discussed. Integr Environ Assess Manag 2019;15:6-18. © 2018 SETAC.

Building Material Use and Associated Environmental Impacts in China 2000-2015

A rapidly increasing use of building materials poses threats to resources and the environment. Using novel, localized life cycle inventories and building material intensity data, this study quantifies the resource use of building materials in mainland China and evaluates their embodied environmental impacts. Newly built floor area and related material consumption grew 11% per annum from 2000 to 2015, leveling off at the end of this period. Concrete, sand, gravel, brick, and cement were the main materials used. Spatially, construction activities expanded from east China into the central part of the country. Cement, steel, and concrete production are the key contributors to associated environmental impacts, e.g., cement and steel each account for around 25% of the global warming potential from building materials. Building materials contribute considerably to the impact categories of human toxicity, fossil depletion, and global warming, emphasizing that greenhouse gas emissions should not be the sole focus of research on environmental impacts of building materials. These findings quantitatively shed light on the urgent need to reduce environmental impacts and to conserve energy in the manufacturing processes of building materials on the national scale.

Live and Let Die? Life Cycle Human Health Impacts from the Use of Tire Studs

Studded tires are used in a number of countries during winter in order to prevent accidents. The use of tire studs is controversial and debated because of human health impacts from increased road particle emissions. The aims of this study are to assess whether the use of tire studs in a Scandinavian studded passenger car actually avoids or causes health impacts from a broader life cycle perspective, and to assess the distribution of these impacts over the life cycle. Life cycle assessment is applied and the disability-adjusted life years indicator is used to quantify the following five types of health impacts: (1) impacts saved in the use phase, (2) particle emissions in the use phase, (3) production system emissions, (4) occupational accidents in the production system, and (5) conflict casualties from revenues of cobalt mining. The results show that the health benefits in the use phase in general are outweighed by the negative impacts during the life cycle. The largest contribution to these negative human health impacts are from use phase particle emissions (67⁻77%) and occupational accidents during artisanal cobalt mining (8⁻18%). About 23⁻33% of the negative impacts occur outside Scandinavia, where the benefits occur. The results inform the current debate and highlight the need for research on alternatives to tire studs with a positive net health balance.

Sensitivity analysis of temporal parameters in a dynamic LCA framework

Including the temporal dimension in the Life Cycle Assessment (LCA) method is a very recent research subject. A complete framework including dynamic Life Cycle Inventory (LCI) and dynamic Life Cycle Impact Assessment (LCIA) was proposed with the possibility to calculate temporal deployment of climate change and ecotoxicity/toxicity indicators. However, the influence of different temporal parameters involved in the new dynamic method was not still evaluated. In the new framework, LCI and LCIA results are obtained as discrete values in function of time (vectors and matrices). The objective of this study is to evaluate the influence of the temporal profile of the dynamic LCI and calculation time span (or time horizon in conventional LCA) on the final LCA results. Additionally, the influence of the time step used for the impact dynamic model resolution was analysed. The range of variation of the different time steps was from 0.5day to 1year. The graphical representation of the dynamic LCA results shown important features such as the period in time and the intensity of the worst or relevant impact values. The use of a fixed time horizon as in conventional LCA does not allow the proper consideration of essential information especially for time periods encompassing the life time of the studied system. Regarding the different time step sizes used for the dynamic LCI definition, they did not have important influence on the dynamic climate change results. At the contrary, the dynamic ecotoxicity and human toxicity impacts were strongly affected by this parameter. Similarly, the time step for impact dynamic model resolution had no influence on climate change calculation (step size up to 1year was supported), while the toxicity model resolution requires adaptive time step definition with maximum size of 0.5day.

Operational integration of time dependent toxicity impact category in dynamic LCA

Life Cycle Assessment (LCA) is the most widely used method for the environmental evaluation of an anthropogenic system and its capabilities no longer need to be proved. However, several limitations have been pointed out by LCA scholars, including the lack of a temporal dimension. The objective of this study is to develop a dynamic approach for calculating the time dependent impacts of human toxicity and ecotoxicity within LCA. A new framework is proposed, which includes dynamic inventory and dynamic impact assessment. This study focuses on the dynamic fate model for substances in the environment, combined with the USEtox® model for toxicity assessment. The method takes into account the noisy and random nature of substance emissions in function of time, as in the real world, and uses a robust solver for the dynamic fate model resolution. No characterization factors are calculated. Instead, a current toxicity is calculated as a function of time i.e. the damage produced per unit of time, together with a time dependent cumulated toxicity, i.e. the total damage produced from time zero to a given time horizon. The latter can be compared with the results obtained by the conventional USEtox® method: their results converge for a very large time horizon (theoretically at infinity). Organic substances are found to disappear relatively rapidly from the environmental compartments (in the time period in which the emissions occur) while inorganic substances (i.e. metals) tend to persist far beyond the emission period.

Improving substance information in USEtox® , part 2: Data for estimating fate and ecosystem exposure factors

The scientific consensus model USEtox^® has been developed since 2003 under the auspices of the United Nations Environment Programme-Society of Environmental Toxicology and Chemistry Life Cycle Initiative as a harmonized approach for characterizing human and freshwater toxicity in life cycle assessment and other comparative assessment frameworks. Using physicochemical substance properties, USEtox quantifies potential human toxicity and freshwater ecotoxicity impacts by combining environmental fate, exposure, and toxicity effects information, considering multimedia fate and multipathway exposure processes. The main source to obtain substance properties for USEtox 1.01 and 2.0 is the Estimation Program Interface (EPI Suite™) from the US Environmental Protection Agency. However, since the development of the original USEtox substance databases, new chemical regulations have been enforced in Europe, such as the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) and the Plant Protection Products regulations. These regulations require that a chemical risk assessment for humans and the environment is performed before a chemical is placed on the European market. Consequently, additional physicochemical property data and new toxicological endpoints are now available for thousands of chemical substances. The aim of the present study was to explore the extent to which the new available data can be used as input for USEtox-especially for application in environmental footprint studies-and to discuss how this would influence the quantification of fate and exposure factors. Initial results show that the choice of data source and the parameters selected can greatly influence fate and exposure factors, leading to potentially different rankings and relative contributions of substances to overall human toxicity and ecotoxicity impacts. Moreover, it is crucial to discuss the relevance of the exposure factor for freshwater ecotoxicity impacts, particularly for persistent highly adsorbing and bioaccumulating substances. Environ Toxicol Chem 2017;36:3463-3470. © 2017 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

Setting the stage for debating the roles of risk assessment and life-cycle assessment of engineered nanomaterials

Although technological and environmental benefits are important stimuli for nanotechnology development, these technologies have been contested from an environmental point of view. The steady growth of applications of engineered nanomaterials has heated up the debate on quantifying the environmental repercussions. The two main scientific methods to address these environmental repercussions are risk assessment and life-cycle assessment. The strengths and weaknesses of each of these methods, and the relation between them, have been a topic of debate in the world of traditional chemistry for over two decades. Here we review recent developments in this debate in general and for the emerging field of nanomaterials specifically. We discuss the pros and cons of four schools of thought for combining and integrating risk assessment and life-cycle assessment and conclude with a plea for action.

Freshwater ecotoxicity impacts from pesticide use in animal and vegetable foods produced in Sweden

Chemical pesticides are widely used in modern agriculture but their potential negative impacts are seldom considered in environmental assessments of food products. This study aims to assess and compare the potential freshwater ecotoxicity impacts due to pesticide use in the primary production of six food products: chicken fillet, minced pork, minced beef, milk, pea soup, and wheat bread. The assessment is based on a detailed and site-specific inventory of pesticide use in the primary production of the food products, all of which are produced in Sweden. Soybeans, used to produce the animal-based food products, are grown in Brazil. Pesticide emissions to air and surface water were calculated using PestLCI v. 2.0.5. Ecotoxicity impacts were assessed using USEtox v. 2.01, and expressed in relation to five functional units. The results show that the animal-based food products have considerably larger impact potentials than the plant-based food products. In relation to kg pea soup, impact potentials of bread, milk, minced beef, chicken fillet and minced pork are ca. 2, 3, 50, 140 and 170 times larger, respectively. All mass-based functional units yield the same ranking. Notably, chicken fillet and minced pork have larger impacts than minced beef and milk, regardless of functional unit, due to extensive use of pesticides, some with high toxicity, in soybean production. This result stands in sharp contrast to typical carbon footprint and land use results which attribute larger impacts to beef than to chicken and pork. Measures for reducing impacts are discussed. In particular, we show that by substituting soybeans with locally sourced feed crops, the impact potentials of minced pork and chicken fillet are reduced by ca. 70 and 90%, respectively. Brazilian soybean production is heavily reliant on pesticides. We propose that weak legislation, in combination with tropical climate and agronomic practices, explains this situation.

Conceptual Framework To Extend Life Cycle Assessment Using Near-Field Human Exposure Modeling and High-Throughput Tools for Chemicals

Life Cycle Assessment (LCA) is a decision-making tool that accounts for multiple impacts across the life cycle of a product or service. This paper presents a conceptual framework to integrate human health impact assessment with risk screening approaches to extend LCA to include near-field chemical sources (e.g., those originating from consumer products and building materials) that have traditionally been excluded from LCA. A new generation of rapid human exposure modeling and high-throughput toxicity testing is transforming chemical risk prioritization and provides an opportunity for integration of screening-level risk assessment (RA) with LCA. The combined LCA and RA approach considers environmental impacts of products alongside risks to human health, which is consistent with regulatory frameworks addressing RA within a sustainability mindset. A case study is presented to juxtapose LCA and risk screening approaches for a chemical used in a consumer product. The case study demonstrates how these new risk screening tools can be used to inform toxicity impact estimates in LCA and highlights needs for future research. The framework provides a basis for developing tools and methods to support decision making on the use of chemicals in products.

Limitations of toxicity characterization in life cycle assessment: Can adverse outcome pathways provide a new foundation?

Life cycle assessment (LCA) has considerable merit for holistic evaluation of product planning, development, production, and disposal, with the inherent benefit of providing a forecast of potential health and environmental impacts. However, a technical review of current life cycle impact assessment (LCIA) methods revealed limitations within the biological effects assessment protocols, including: simplistic assessment approaches and models; an inability to integrate emerging types of toxicity data; a reliance on linear impact assessment models; a lack of methods to mitigate uncertainty; and no explicit consideration of effects in species of concern. The purpose of the current study is to demonstrate that a new concept in toxicological and regulatory assessment, the adverse outcome pathway (AOP), has many useful attributes of potential use to ameliorate many of these problems, to expand data utility and model robustness, and to enable more accurate and defensible biological effects assessments within LCIA. Background, context, and examples have been provided to demonstrate these potential benefits. We additionally propose that these benefits can be most effectively realized through development of quantitative AOPs (qAOPs) crafted to meet the needs of the LCIA framework. As a means to stimulate qAOP research and development in support of LCIA, we propose 3 conceptual classes of qAOP, each with unique inherent attributes for supporting LCIA: 1) mechanistic, including computational toxicology models; 2) probabilistic, including Bayesian networks and supervised machine learning models; and 3) weight of evidence, including models built using decision-analytic methods. Overall, we have highlighted a number of potential applications of qAOPs that can refine and add value to LCIA. As the AOP concept and support framework matures, we see the potential for qAOPs to serve a foundational role for next-generation effects characterization within LCIA. Integr Environ Assess Manag 2016;12:580-590. Published 2015. This article is a US Government work and is in the public domain in the USA.

Spatial variability versus parameter uncertainty in freshwater fate and exposure factors of chemicals

We compared the influence of spatial variability in environmental characteristics and the uncertainty in measured substance properties of seven chemicals on freshwater fate factors (FFs), representing the residence time in the freshwater environment, and on exposure factors (XFs), representing the dissolved fraction of a chemical. The influence of spatial variability was quantified using the SimpleBox model in which Europe was divided in 100 × 100 km regions, nested in a regional (300 × 300 km) and supra-regional (500 × 500 km) scale. Uncertainty in substance properties was quantified by means of probabilistic modelling. Spatial variability and parameter uncertainty were expressed by the ratio k of the 95%ile and 5%ile of the FF and XF. Our analysis shows that spatial variability ranges in FFs of persistent chemicals that partition predominantly into one environmental compartment was up to 2 orders of magnitude larger compared to uncertainty. For the other (less persistent) chemicals, uncertainty in the FF was up to 1 order of magnitude larger than spatial variability. Variability and uncertainty in freshwater XFs of the seven chemicals was negligible (k < 1.5). We found that, depending on the chemical and emission scenario, accounting for region-specific environmental characteristics in multimedia fate modelling, as well as accounting for parameter uncertainty, can have a significant influence on freshwater fate factor predictions. Therefore, we conclude that it is important that fate factors should not only account for parameter uncertainty, but for spatial variability as well, as this further increases the reliability of ecotoxicological impacts in LCA.

Use of digestate from a decentralized on-farm biogas plant as fertilizer in soils: An ecotoxicological study for future indicators in risk and life cycle assessment

Over the last decade, the number of decentralized farm biogas plants has increased significantly in the EU. This development leads not only to an increasing amount of biogas produced, but also to a higher amount of digestate obtained. One of the most attractive options to manage the digestate is to apply it as biofertiliser to the soil, because this gives the opportunity of recovering the nutrients, primarily nitrogen and phosphorus, and of attenuating the loss of organic matter suffered by soils under agricultural exploitation. Studies have claimed that digestates can present a residual biodegradability, and contain complex organic elements, salts or pathogenic bacteria that can damage terrestrial organisms. However few ecotoxicological studies have been performed to evaluate the ecological impact of digestate application on soil. In this study, the use of digestate as biofertiliser in agriculture was assessed by a battery of ecotoxicological tests considering the potential pollutants present in the digestate as a whole by using the "matrix-based" approach (also known as "whole effluent toxicity" for eluates or wastewater effluents). The direct and indirect tests included plant bioassays with Lepidium sativum, earthworm bioassays with Eisenia fetida, aquatic organisms (Artemia sp. and Daphnia magna) and luminescent bacteria bioassays (Vibrio fischeri). Direct tests occurred to be more sensitive than indirect tests. The earthworm bioassays did not show serious negative effects for concentrations up to 15% (dry weight/dry weight percent, w/w dm) and the plant bioassays showed no negative effect, but rather a positive one for concentrations lower than 20% (w/w dm), which encourages the use of digestate as a biofertiliser in agriculture provided that proper concentrations are used. The indirect tests, on the eluate, with the using aquatic organisms and luminescent bacteria showed an LC50 value of 13.61% volume/volume percent, v/v) for D. magna and no toxicity for Artemia sp. and V. fischeri. The ecotoxicological parameters obtained from the experimental activity have been analyzed so that they could serve in both ecological risk assessment (ERA) and life cycle assessment (LCA) to assess the risks and impacts of using digestate as a biofertiliser in agriculture. An interim effect factor of 1.17E-3m(3)/kg-in-soil is advocated and can be used in life cycle impact assessment modelling of terrestrial ecotoxicity. A predicted non effect concentration for soil organisms was defined at 341 mg-digestate/kg-soil and can be used for the dose-response assessment step in ERA. Although these values are recommended for use in ERA and LCA applications, it should be stressed that they underlie important uncertainties, which should be reduced by increasing the number of toxicological tests, in particular of chronic studies conducted at different trophic levels.

Assessment of Metal Toxicity in Marine Ecosystems: Comparative Toxicity Potentials for Nine Cationic Metals in Coastal Seawater

This study is a first attempt to develop globally applicable and spatially differentiated marine comparative toxicity potentials (CTPs) or ecotoxicity characterization factors for metals in coastal seawater for use in life cycle assessment. The toxicity potentials are based exclusively on marine ecotoxicity data and take account of metal speciation and bioavailability. CTPs were developed for nine cationic metals (Cd, Cr(III), Co, Cu(II), Fe(III), Mn, Ni, Pb, and Zn) in 64 large marine ecosystems (LMEs) covering all coastal waters in the world. The results showed that the CTP of a specific metal varies 3-4 orders of magnitude across LMEs, largely due to different seawater residence times. Therefore, the highest toxicity potential for metals was found in the LMEs with the longest seawater residence times. Across metals, the highest CTPs were observed for Cd, Pb, and Zn. At the concentration levels occurring in coastal seawaters, Fe acts not as a toxic agent but as an essential nutrient and thus has CTPs of zero.

Canola oil is an excellent vehicle for eliminating pesticide residues in aqueous ginseng extract

Background

We previously reported that two-phase partition chromatography between ginseng water extract and soybean oil efficiently eliminated pesticide residues. However, an undesirable odor and an unpalatable taste unique to soybean oil were two major disadvantages of the method. This study was carried out to find an alternative vegetable oil that is cost effective, labor effective, and efficient without leaving an undesirable taste and smell.

Methods

We employed six vegetable oils that were available at a grocery store. A 1-mL sample of the corresponding oil containing a total of 32 pesticides, representing four categories, was mixed with 10% aqueous ginseng extract (20 mL) and equivalent vegetable oil (7 mL) in Falcon tubes. The final concentration of the pesticides in the mixture (28 mL) was adjusted to approximately 2 ppm. In addition, pesticides for spiking were clustered depending on the analytical equipment (GC/HPLC), detection mode (electron capture detector/nitrogen–phosphorus detector), or retention time used. Samples were harvested and subjected to quantitative analysis of the pesticides.

Results

Soybean oil demonstrated the highest efficiency in partitioning pesticide residues in the ginseng extract to the oil phase. However, canola oil gave the best result in an organoleptic test due to the lack of undesirable odor and unpalatable taste. Furthermore, the qualitative and quantitative changes of ginsenosides evaluated by TLC and HPLC, respectively, revealed no notable change before or after canola oil treatment.

Conclusion

We suggest that canola oil is an excellent vehicle with respect to its organoleptic property, cost-effectiveness and efficiency of eliminating pesticide residues in ginseng extract.

Data-Driven Method to Estimate Nonlinear Chemical Equivalence

There is great need to express the impacts of chemicals found in the environment in terms of effects from alternative chemicals of interest. Methods currently employed in fields such as life-cycle assessment, risk assessment, mixtures toxicology, and pharmacology rely mostly on heuristic arguments to justify the use of linear relationships in the construction of "equivalency factors," which aim to model these concentration-concentration correlations. However, the use of linear models, even at low concentrations, oversimplifies the nonlinear nature of the concentration-response curve, therefore introducing error into calculations involving these factors. We address this problem by reporting a method to determine a concentration-concentration relationship between two chemicals based on the full extent of experimentally derived concentration-response curves. Although this method can be easily generalized, we develop and illustrate it from the perspective of toxicology, in which we provide equations relating the sigmoid and non-monotone, or "biphasic," responses typical of the field. The resulting concentration-concentration relationships are manifestly nonlinear for nearly any chemical level, even at the very low concentrations common to environmental measurements. We demonstrate the method using real-world examples of toxicological data which may exhibit sigmoid and biphasic mortality curves. Finally, we use our models to calculate equivalency factors, and show that traditional results are recovered only when the concentration-response curves are "parallel," which has been noted before, but we make formal here by providing mathematical conditions on the validity of this approach.

Beyond the material grave: Life Cycle Impact Assessment of leaching from secondary materials in road and earth constructions

In industrialized countries, large amounts of mineral wastes are produced. They are re-used in various ways, particularly in road and earth constructions, substituting primary resources such as gravel. However, they may also contain pollutants, such as heavy metals, which may be leached to the groundwater. The toxic impacts of these emissions are so far often neglected within Life Cycle Assessments (LCA) of products or waste treatment services and thus, potentially large environmental impacts are currently missed. This study aims at closing this gap by assessing the ecotoxic impacts of heavy metal leaching from industrial mineral wastes in road and earth constructions. The flows of metals such as Sb, As, Pb, Cd, Cr, Cu, Mo, Ni, V and Zn originating from three typical constructions to the environment are quantified, their fate in the environment is assessed and potential ecotoxic effects evaluated. For our reference country, Germany, the industrial wastes that are applied as Granular Secondary Construction Material (GSCM) carry more than 45,000 t of diverse heavy metals per year. Depending on the material quality and construction type applied, up to 150 t of heavy metals may leach to the environment within the first 100 years after construction. Heavy metal retardation in subsoil can potentially reduce the fate to groundwater by up to 100%. One major challenge of integrating leaching from constructions into macro-scale LCA frameworks is the high variability in micro-scale technical and geographical factors, such as material qualities, construction types and soil types. In our work, we consider a broad range of parameter values in the modeling of leaching and fate. This allows distinguishing between the impacts of various road constructions, as well as sites with different soil properties. The findings of this study promote the quantitative consideration of environmental impacts of long-term leaching in Life Cycle Assessment, complementing site-specific risk assessment, for the design of waste management strategies, particularly in the construction sector.

Uncertainty in multi-media fate and transport models: a case study for TNT life cycle assessment

Life cycle assessment (LCA) is an evaluation method used by decision-makers to help assess the relative environmental impacts of various industrial processes. Despite that many LCA methods remain sensitive to uncertain input data, which can reduce the utility of their results, uncertainty arising from constituent LCA models remains poorly understood. Here, we begin to address this problem by evaluating the extent to which parameter-value uncertainty affects the SimpleBox 2.0 fate and transport model, which serves as a backbone for many LCA ecotoxicological impact categories. Two Monte Carlo type sampling methods were used to evaluate dispersion in steady-state concentration values for three chemicals involved in grenade production: toluene, 2,4-dinitrotoluene (2,4-DNT), and 2,4,6-trinitrotoluene (TNT). Parameters were first sampled stochastically one-at-a-time, then by randomly exploring a local patch of the parameter space. We confirmed that global temperatures contribute primarily to the overall variance of model results, which at most spanned approximately 8 decades in magnitude. These results are consistent with previous results obtained for the whole of the LCA method. LCA methods carry out calculations iteratively; a reduction in the error of a single component, such as the fate and transport model, may therefore improve its performance and utility as a decision-making aid.

Bridging the gap between life cycle inventory and impact assessment for toxicological assessments of pesticides used in crop production

In Life Cycle Assessment (LCA), the Life Cycle Inventory (LCI) provides emission data to the various environmental compartments and Life Cycle Impact Assessment (LCIA) determines the final distribution, fate and effects. Due to the overlap between the Technosphere (anthropogenic system) and Ecosphere (environment) in agricultural case studies, it is, however, complicated to establish what LCI needs to capture and where LCIA takes over. This paper aims to provide guidance and improvements of LCI/LCIA boundary definitions, in the dimensions of space and time. For this, a literature review was conducted to provide a clear overview of available methods and models for both LCI and LCIA regarding toxicological assessments of pesticides used in crop production. Guidelines are provided to overcome the gaps between LCI and LCIA modeling, and prevent the overlaps in their respective operational spheres. The proposed framework provides a starting point for LCA practitioners to gather the right data and use the proper models to include all relevant emission and exposure routes where possible. It is also able to predict a clear distinction between efficient and inefficient management practices (e.g. using different application rates, washing and rinsing management, etc.). By applying this framework for toxicological assessments of pesticides, LCI and LCIA can be directly linked, removing any overlaps or gaps in between the two distinct LCA steps.

Assessing predictive uncertainty in comparative toxicity potentials of triazoles

Comparative toxicity potentials (CTPs) quantify the potential ecotoxicological impacts of chemicals per unit of emission. They are the product of a substance's environmental fate, exposure, and hazardous concentration. When empirical data are lacking, substance properties can be predicted. The goal of the present study was to assess the influence of predictive uncertainty in substance property predictions on the CTPs of triazoles. Physicochemical and toxic properties were predicted with quantitative structure-activity relationships (QSARs), and uncertainty in the predictions was quantified with use of the data underlying the QSARs. Degradation half-lives were based on a probability distribution representing experimental half-lives of triazoles. Uncertainty related to the species' sample size that was present in the prediction of the hazardous aquatic concentration was also included. All parameter uncertainties were treated as probability distributions, and propagated by Monte Carlo simulations. The 90% confidence interval of the CTPs typically spanned nearly 4 orders of magnitude. The CTP uncertainty was mainly determined by uncertainty in soil sorption and soil degradation rates, together with the small number of species sampled. In contrast, uncertainty in species-specific toxicity predictions contributed relatively little. The findings imply that the reliability of CTP predictions for the chemicals studied can be improved particularly by including experimental data for soil sorption and soil degradation, and by developing toxicity QSARs for more species.

Energy efficiency for the removal of non-polar pollutants during ultraviolet irradiation, visible light photocatalysis and ozonation of a wastewater effluent

This study aims to assess the removal of a set of non-polar pollutants in biologically treated wastewater using ozonation, ultraviolet (UV 254 nm low pressure mercury lamp) and visible light (Xe-arc lamp) irradiation as well as visible light photocatalysis using Ce-doped TiO2. The compounds tracked include UV filters, synthetic musks, herbicides, insecticides, antiseptics and polyaromatic hydrocarbons. Raw wastewater and treated samples were analyzed using stir-bar sorptive extraction coupled with comprehensive two-dimensional gas chromatography (SBSE-CG × GC-TOF-MS). Ozone treatment could remove most pollutants with a global efficiency of over 95% for 209 μM ozone dosage. UV irradiation reduced the total concentration of the sixteen pollutants tested by an average of 63% with high removal of the sunscreen 2-ethylhexyl trans-4-methoxycinnamate (EHMC), the synthetic musk 7-acetyl-1,1,3,4,4,6-hexamethyltetrahydronaphthalene (tonalide, AHTN) and several herbicides. Visible light Ce-TiO2 photocatalysis reached ~70% overall removal with particularly high efficiency for synthetic musks. In terms of power usage efficiency expressed as nmol kJ(-1), the results showed that ozonation was by far the most efficient process, ten-fold over Xe/Ce-TiO2 visible light photocatalysis, the latter being in turn considerably more efficient than UV irradiation. In all cases the efficiency decreased along the treatments due to the lower reaction rate at lower pollutant concentration. The use of photocatalysis greatly improved the efficiency of visible light irradiation. The collector area per order decreased from 9.14 ± 5.11 m(2) m(-3) order(-1) for visible light irradiation to 0.16 ± 0.03 m(2) m(-3) order(-1) for Ce-TiO2 photocatalysis. The toxicity of treated wastewater was assessed using the green alga Pseudokirchneriella subcapitata. Ozonation reduced the toxicity of treated wastewater, while UV irradiation and visible light photocatalysis limited by 20-25% the algal growth due to the accumulation of reaction by-products. Three transformation products were identified and tracked along the treatments.

Net energy production and emissions mitigation of domestic wastewater treatment system: a comparison of different biogas-sludge use alternatives

Wastewater treatment systems are increasingly designed for the recovery of valuable chemicals and energy in addition to waste stream disposal. Herein, the life-cycle energy production and emissions mitigation of a typical domestic wastewater treatment system were assessed, in which different combinations of biogas use and sludge processing lines for industrial or household applications were considered. The results suggested that the reuse of biogas and sludge was so important in the system's overall energy balance and environmental performance that it may offset the cost in the plant's installation and operation. Combined heat and power and household utilization were two prior options for net energy production, provided an ideal power conversion efficiency and biogas production. The joint application of household biogas use and sludge nutrient processing achieved both high net energy production and significant environmental remediation across all impact categories, representing the optimal tradeoff for domestic wastewater treatment.

Environmental optimization of continuous flow ozonation for urban wastewater reclamation

Wastewater samples from the secondary clarifier of two treatment plants were spiked in the microgram-to-tens-of-microgram per liter range with diuron (herbicide), ibuprofen and diclofenac (anti-inflammatory drugs), sulfamethoxazole and erythromycin (antibiotics), bezafibrate and gemfibrozil (lipid regulators), atenolol (β-blocker), carbamazepine (anti-epileptic), hydrochlorothiazide (diuretic), caffeine (stimulant) and N-acetyl-4-amino-antipiryne, a metabolite of the antipyretic drug dypirone. They were subsequently ozonated in continuous flow using 1.2L lab-scale bubble columns. The concentration of all spiking compounds was monitored in the outlet stream. The effects of varying ozone input, expressed as energy per unit volume, and water flow rate, and of using single or double column were studied in relation to the efficiency of ozone usage and the ratio of pollutant depletion. The ozone dosage required to treat both wastewaters with pollutant depletion of >90% was in the 5.5-8.5 mg/L range with ozone efficiencies greater than 80% depending on the type of wastewater and the operating conditions. This represented 100-200 mol of ozone transferred per mole of pollutant removed. Direct and indirect environmental impacts of ozonation were assessed according to Life Cycle Assessment, a technique that helped identify the most effective treatments in terms of potential toxicity reduction, as well as of toxicity reduction per unit mass of greenhouse-gas emissions, which were used as an indicator of environmental efficiency. A trade-off between environmental effectiveness (toxicity reduction) and greenhouse-gas emissions was observed since maximizing toxicity removal led to higher greenhouse-gas emissions, due to the latter's relatively high ozone requirements. Also, there is an environmental trade-off between effectiveness and efficiency. Our results indicate that an efficient use of ozone was not compatible with a full pollutant removal.

LCA data quality: sensitivity and uncertainty analysis

Life cycle assessment (LCA) data quality issues were investigated by using case studies on products from starch-polyvinyl alcohol based biopolymers and petrochemical alternatives. The time horizon chosen for the characterization models was shown to be an important sensitive parameter for the environmental profiles of all the polymers. In the global warming potential and the toxicity potential categories the comparison between biopolymers and petrochemical counterparts altered as the time horizon extended from 20 years to infinite time. These case studies demonstrated that the use of a single time horizon provide only one perspective on the LCA outcomes which could introduce an inadvertent bias into LCA outcomes especially in toxicity impact categories and thus dynamic LCA characterization models with varying time horizons are recommended as a measure of the robustness for LCAs especially comparative assessments. This study also presents an approach to integrate statistical methods into LCA models for analyzing uncertainty in industrial and computer-simulated datasets. We calibrated probabilities for the LCA outcomes for biopolymer products arising from uncertainty in the inventory and from data variation characteristics this has enabled assigning confidence to the LCIA outcomes in specific impact categories for the biopolymer vs. petrochemical polymer comparisons undertaken. Uncertainty combined with the sensitivity analysis carried out in this study has led to a transparent increase in confidence in the LCA findings. We conclude that LCAs lacking explicit interpretation of the degree of uncertainty and sensitivities are of limited value as robust evidence for decision making or comparative assertions.

Life-cycle energy production and emissions mitigation by comprehensive biogas-digestate utilization

In the context of global energy shortages and climate change, developing biogas plants with links to agricultural system has become an important strategy for cleaner rural energy and renewable agriculture. In this study, a life-cycle energy and environmental assessment was performed for a biogas-digestate utilization system in China. The results suggest that biogas utilization (heating, illumination, and fuel) and comprehensive digestate reuse are of equal importance in the total energy production of the system, and they also play an important role in systemic greenhouse gas mitigation. Improvement can be achieved in both energy production and emissions mitigation when the ratio of the current three biogas utilization pathways is adjusted. Regarding digestate reuse, a tradeoff between energy and environmental performance can be obtained by focusing on the substitution for top-dressing, base fertilizers, and the application to seed soaking.

A concurrent neuro-fuzzy inference system for screening the ecological risk in rivers

PURPOSE

A conceptual model to assess water quality in river basins was developed here. The model was based on ecological risk assessment principles, and incorporated a novel ranking and scoring system, based on self-organizing maps, to account for the likely ecological hazards posed by the presence of chemical substances in freshwater. This approach was used to study the chemical pollution in the Ebro River basin (Spain), whose currently applied environmental indices must be revised in terms of scientific accuracy.

METHODS

Ecological hazard indexes for chemical substances were calculated by pattern recognition of persistence, bioaccumulation, and toxicity properties. A fuzzy inference system was proposed to compute ecological risk points (ERP), which are a combination of the ecological hazard to aquatic sensitive organisms and environmental concentrations. By aggregating ERP, changes in water quality over time were estimated.

RESULTS

The proposed concurrent neuro-fuzzy model was applied to a comprehensive dataset of the network controlling the levels of dangerous substances, such as metals, pesticides, and polycyclic aromatic hydrocarbons, in the Ebro river basin. The approach was verified by comparison versus biological monitoring. The results showed that water quality in the Ebro river basin is affected by presence of micro-pollutants.

CONCLUSIONS

The ERP approach is suitable to analyze overall trends of potential threats to freshwater ecosystems by anticipating the likely impacts from multiple substances, although it does not account for synergies among pollutants. Anyhow, the model produces a convenient indicator to search for pollutant levels of concern.

On process optimization considering LCA methodology

The goal of this work is to research the state-of-the-art in process optimization techniques and tools based on LCA, focused in the process engineering field. A collection of methods, approaches, applications, specific software packages, and insights regarding experiences and progress made in applying the LCA methodology coupled to optimization frameworks is provided, and general trends are identified. The "cradle-to-gate" concept to define the system boundaries is the most used approach in practice, instead of the "cradle-to-grave" approach. Normally, the relationship between inventory data and impact category indicators is linearly expressed by the characterization factors; then, synergic effects of the contaminants are neglected. Among the LCIA methods, the eco-indicator 99, which is based on the endpoint category and the panel method, is the most used in practice. A single environmental impact function, resulting from the aggregation of environmental impacts, is formulated as the environmental objective in most analyzed cases. SimaPro is the most used software for LCA applications in literature analyzed. The multi-objective optimization is the most used approach for dealing with this kind of problems, where the ε-constraint method for generating the Pareto set is the most applied technique. However, a renewed interest in formulating a single economic objective function in optimization frameworks can be observed, favored by the development of life cycle cost software and progress made in assessing costs of environmental externalities. Finally, a trend to deal with multi-period scenarios into integrated LCA-optimization frameworks can be distinguished providing more accurate results upon data availability.

Prospective environmental life cycle assessment of nanosilver T-shirts

A cradle-to-grave life cycle assessment (LCA) is performed to compare nanosilver T-shirts with conventional T-shirts with and without biocidal treatment. For nanosilver production and textile incorporation, we investigate two processes: flame spray pyrolysis (FSP) and plasma polymerization with silver co-sputtering (PlaSpu). Prospective environmental impacts due to increased nanosilver T-shirt commercialization are estimated with six scenarios. Results show significant differences in environmental burdens between nanoparticle production technologies: The "cradle-to-gate" climate footprint of the production of a nanosilver T-shirt is 2.70 kg of CO(2)-equiv (FSP) and 7.67-166 kg of CO(2)-equiv (PlaSpu, varying maturity stages). Production of conventional T-shirts with and without the biocide triclosan has emissions of 2.55 kg of CO(2)-equiv (contribution from triclosan insignificant). Consumer behavior considerably affects the environmental impacts during the use phase. Lower washing frequencies can compensate for the increased climate footprint of FSP nanosilver T-shirt production. The toxic releases from washing and disposal in the life cycle of T-shirts appear to be of minor relevance. By contrast, the production phase may be rather significant due to toxic silver emissions at the mining site if high silver quantities are required.

Implications of geographic variability on Comparative Toxicity Potentials of Cu, Ni and Zn in freshwaters of Canadian ecoregions

Current methods of estimating potential environmental impacts of metals in hazard and Life Cycle Impact Assessment (LCIA) do not consider differences in chemistry and landscape properties between geographic sites. Here, we developed and applied a model for regional aquatic impact characterization of metals using an updated method for estimating environmental fate factor (FF), bioavailability factor (BF) and aquatic ecotoxicity factor (EF). We applied the model to analyze differences in Comparative Toxicity Potentials (CTPs) of Cu, Ni and Zn for 24 Canadian ecoregions. The combined impacts of regional variability in ambient chemistry (in particular DOC, pH and hardness) and landscape properties (water residence time) can change the CTPs of these metals for freshwater by up to three orders of magnitude and change the relative ranking of metal hazard between ecoregions. Variation among Canadian freshwater chemistries and landscape characteristics influence the FFs within two orders of magnitude, BFs within two orders of magnitude for Ni and Zn and four orders of magnitude for Cu, and EFs within one order of magnitude. Sensitivity of metal FFs to environmental parameters alone spans three orders of magnitude when a constant water chemistry was used for all ecoregions. These results indicate that application of regionalised metal CTPs can have a significant influence in the analysis of ecotoxicological impacts in the life cycle assessment of products and processes.

Assessment of the impact on human health of industrial emissions to air: does the result depend on the applied method?

The impact on human health of substances emitted to air by the Flemish industry was calculated with characterization factors (CFs) provided by the CML, Eco-indicator 99, EPS, EDIP and USEtox impact assessment methods. A comparison of the results pointed out that the choice of the CFs can greatly influence conclusions on the trend of the impact over time and on the relative contribution of the individual substances. If the impact on human health of organic substances and heavy metals was assessed separately, the differences between methods were less pronounced. In this case, the impacts on human health obtained by simply dividing the emitted masses of substances by the respective minimal risk concentrations or minimal risk doses, were comparable to those calculated with the CFs of the model-based methods.

ERICA: A multiparametric toxicological risk index for the assessment of environmental healthiness

A risk assessment strategy considering the impact of chemicals on the whole ecosystem has been developed in order to create a sound and useful method for quantifying and comparing the global risk posed by the main different hazardous chemicals found in the environment. This index, called Environmental Risk Index for Chemical Assessment (ERICA), merges in a single number the environmental assessment, the human health risk assessment and the uncertainty due to missing or uncertain data. ERICA uses a dedicated scoring system with parameters for the main characteristics of the pollutants. The main advantage is that it preserves a simple approach by condensing in this single value an analysis of the risk for the area under observation. ERICA quantifies and compares the global risk posed by hazardous chemicals found in the environment and can be considered a diagnostic and prognostic method for environmental contaminants in critical and potentially dangerous sites, such as incinerators, landfills and industrial areas or in broader geographical areas. The application of the proposed integrated index provides a preliminary quantitative analysis of possible environmental alert due to the presence of one or some pollutants in the investigated site. This paper presents the method and the equations behind the index and a first case study based on the Italian legislation and a pilot study located on the Italian seacoast.

Comparative environmental impacts of glyphosate and conventional herbicides when used with glyphosate-tolerant and non-tolerant crops

The introduction of glyphosate-tolerant (GT) crops is expected to mitigate the environmental contamination by herbicides because glyphosate is less persistent and toxic than the herbicides used on non-GT crops. Here, we compared the environmental balances of herbicide applications for both crop types in three French field trials. The dynamic of herbicides and their metabolites in soil, groundwater and air was simulated with PRZM model and compared to field measurements. The associated impacts were aggregated with toxicity potentials calculated with the fate and exposure model USES for several environmental endpoints. The impacts of GT systems were lower than those of non-GT systems, but the accumulation in soils of one glyphosate metabolite (aminomethylphosphonic acid) questions the sustainability of GT systems. The magnitude of the impacts depends on the rates and frequency of glyphosate application being highest for GT maize monoculture and lowest for combination of GT oilseed rape and non-GT sugarbeet crops.

New method for calculating comparative toxicity potential of cationic metals in freshwater: application to copper, nickel, and zinc

Current practice in chemical hazard ranking and toxic impact assessments is to estimate fate and toxicity assuming the chemical exists in dissolved and particulate phases and, for metals, that all dissolved species are equally bioavailable. This introduces significant error since metal effects are related to the truly dissolved phase and free metal ion within it, not the total dissolved phase. We introduce a Bioavailability Factor (BF) to the calculation of hazard or Comparative Toxicity Potentials (CTPs) (also known as Characterization Factors; CFs) for use in Life Cycle Impact Assessment (LCIA). The method uses for calculation (1) USEtox for environmental fate, (2) WHAM 6.0 for metal partitioning and speciation in aquatic systems, and (3) Biotic Ligand Model (BLM) for average toxicity. For 12 EU water-types, we calculated medians (range) of CTPs of 1.5 x 10(4) (1.5 x 10(2) to 1.2 x 10(5)), 5.6 x 10(4) (9.4 x 10(3) to 4.1 x 10(5)), and 2.1 x 10(4) (7 x 10(3) to 5.8 x 10(4)) day*m(3)/kg for Cu, Ni, and Zn, respectively, which are up to approximately 1000 times lower than previous values. The greatest contributor to variability in CTPs was the BF, followed by toxicity Effect Factor (EF). The importance of the choice of water-type is shown by changes in the relative ranking of CTPs, which are equally influenced by water chemistry and inherent metal-specific differences.

GLOBOX: A spatially differentiated global fate, intake and effect model for toxicity assessment in LCA

GLOBOX is a model for the calculation of spatially differentiated LCA toxicity characterisation factors on a global scale. It can also be used for human and environmental risk assessment. The GLOBOX model contains equations for the calculation of fate, intake and effect factors, and equations for the calculation of LCA characterisation factors for human toxicity and ecotoxicity. The model is differentiated on the level of 239 countries/territories and 50 seas/oceans. Each region has its own set of homogeneous compartments, and the regions are interconnected by atmospheric and aquatic flows. Multimedia transport and degradation calculations are largely based on the EUSES 2.0 multimedia model, and are supplemented by specific equations to account for the advective air and water transport between different countries and/or seas. Metal-specific equations are added to account for speciation in fresh and marine surface water. Distribution parameters for multimedia transport equations are differentiated per country or sea with respect to geographic features, hydrology, and climate. The model has been tested with nitrobenzene as a test chemical, for emissions to all countries in the world. Spatially differentiated characterisation factors turn out to show wide ranges of variation between countries, especially for releases to inland water and soil compartments. Geographic position, distribution of lakes and rivers and variations in environmental temperature and rain rate are decisive parameters for a number of different characterisation factors. Population density and dietary intake play central roles in the variation of characterisation factors for human toxicity. Among the countries that show substantial deviations from average values of the characterisation factors are not only small and remote islands, but also countries with a significant economic production rate, as indicated by their GDPs. It is concluded that spatial differentiation between countries is an important step forward with respect to the improvement of LCA toxicity characterisation factors.