Freshwater Ecotoxicity Potential Research Articles

Eco-friendly microalgae harvesting using lipid-cored particles with a comparative life-cycle assessment

This study proposed an innovative approach using lipid-cored particles (LCPs) aimed at addressing the efficiency, cost, and environmental impact challenges in microalgae harvesting. Cetyltrimethylammonium bromide (CTAB) and chitosan (CS) were used to modify LCPs and to optimize efficiency and investigate the mechanisms of harvesting with Chlorella vulgaris. Results showed that a maximum harvesting efficiency of 97.14 % was achieved using CS-LCPs. Zeta potential and microscopic images revealed the presence of embedded CS-LCPs within microalgal flocs. Fractal dimension data suggested looser aggregates of CS-LCPs and Chlorella vulgaris, corroborated by Excitation-emission matrices (EEM) analysis further confirmation the presence of bridging networks. Moreover, life cycle assessment of five harvesting methods pointed freshwater ecotoxicity potential (FEP) and terrestrial ecotoxicity potential (TEP) as major environmental impacts, mainly from flocculant use, carrier production, and electricity consumption. Notably, LCPs showed the lowest global warming potential (GWP) at 1.54 kg CO2 eq, offering a viable, low-carbon, cost-effective harvesting alternative.

Life cycle assessment of fermentative xylitol production from wheat bran: A comparative evaluation of sulphuric acid and chemical-free wet air oxidation-based pretreatment

Xylitol, a sugar alcohol is a low-calorie sweetener has wide applications in food and pharmaceutical industry and hence considered as a high value premium product. The conventional methods for fermentative xylitol production uses chemicals (acid/alkali) which generates inhibitors affecting fermentation and downstream purification of xylitol. In the present study, wet air oxidation was evaluated as a chemical-free pretreatment option of wheat bran for xylose release which is subsequently fermented to xylitol. Life cycle assessment was used as a tool to compare wet air oxidation with conventional methods like dilute acid pretreatment for valorization of wheat bran, a model agro-industrial remnant. A comparative evaluation of wet air oxidation and dilute acid pretreatment was investigated for fermentative production of xylitol (1 g/L as functional unit) with the aim of identifying the process involved with the lowest environmental impact, while also demonstrating the higher xylose recovery of 13.52 g/L coupled with FO based concentration unit. The inputs and outputs of the process involving energy use, chemicals employed, and emissions produced were evaluated with respect to food and environment perspective. Environmental impacts of wet air oxidation and dilute acid pretreatment with fermentative xylitol production of 6.134 and 1.42 g/L, respectively showed emission results of 1.476 and 5.288 kg CO2 equivalent, respectively. Though, primary energy demand of wet air oxidation was almost found to be equivalent to dilute acid, due to energy penalty for reactor mixing was higher in wet air oxidation. However, energy demand of wet air oxidation-based pretreatment was found to be energy efficient by 30% as compared to dilute acid. Coupling biogas reduces energy demand by 3.5%. The reduction in impacts relevant to food safety namely, marine aquatic and freshwater ecotoxicity potential were found by 74.29% and 84.97% substantially lower in wet air oxidation as compared to dilute acid based xylitol production. The effect of sulphate, as input form of sulphuric acid in dilute acid showed an impact of 3.83 folds higher on human toxicity potential as compared to wet air oxidation pretreatment process.

The environmental impact and development direction of grass carp, Ctenopharyngodon idella, aquaculture

AbstractGrass carp, Ctenopharyngodon idella, is the largest freshwater aquaculture fish species worldwide. However, its environmental impacts are increasingly controversial. In this paper, we considered the production of a 1500 g commercial grass carp as an example, analyzed through a life cycle assessment. The results showed that the indicators of global warming potential (GWP), acidification potential, eutrophication potential, freshwater eco‐toxicity potential (FAETP), land competition (LC), and fossil energy consumption of producing 1 kg of grass carp were equivalent to 5.7267 kg of CO2, 0.0648 kg of 1,4‐DCB0, 0.0010 kg of P, 0.0276 kg of SO2, 8.2951 m2, 0.3491 kg of oil, respectively, and were mainly from feed processing and water pollution. Compared with pig, beef, and sheep production, grass carp production has lower environmental impacts, but in terms of GWP, FAETP, and LC were significantly higher than chicken production, especially water pollution and discharge, which is an important consideration. This study clarifies the direction of grass carp production and key focus areas include producing low carbon and nitrogen emission feed, application of ecological engineering aquaculture system, intelligent mechanization technology and equipment.

Life cycle assessment of waste management in rural areas in the transition period from mixed collection to source-separation

Rural solid waste management is essential for fulfilling sustainable development goals, especially in developing countries. However, quantitative study on this aspect has been little and far behind the urban areas. In this study, the environmental impacts of four typical rural solid waste management systems were quantified using life cycle assessment based on data from field investigations of five towns across four seasons. Sensitivity analysis was used to determine the most influential parameters. The results showed that landfilling mixed waste contributed the highest environmental impacts. By substituting landfilling with incineration, the environmental impacts (i.e., global warming potential, terrestrial acidification potential, fossil resource scarcity, freshwater ecotoxicity potential) dropped about 110%-900%. When shifting collection schemes to source separation, the environmental impacts also decreased by approximately 50%-200%. However, the environmental impacts of applying source separation to the existing management systems with mixed collection and disposal facilities of landfill or waste-to-energy (WTE) incineration are unclear and depend on the performance of decentralized composting and anaerobic digestion facilities, which need further investigations. Compared with urban cases, the landfill in rural areas emits higher greenhouse gas (GHG), and WTE incineration plants in rural areas have similar GHG emissions to WTE in urban areas. Besides, energy recovery was the most influential process in WTE systems and a 1% improvement on that would bring over 10% progress on global warming potential impact category. These findings can be useful for improving and developing rural domestic waste treatment in China and other developing countries.

Ocena potencjalnej toksyczności dla ekosystemu wody słodkiej w wyniku chemicznej ochrony kukurydzy w różnych systemach uprawy roli

The aim of the study was to assess the impact of the use of plant protection products on the freshwater ecosystem in the production of maize for grain in different soil tillage systems. The analyzes were performed on the basis of data on chemical protection of maize in conventional tillage, reduced tillage and direct sowing. The data were obtained from 15 selected farms located in the Wielkopolskie Voivodeship. The studies were conducted in accordance with the life cycle assessment methodology. Using the PestLCI 2.08 model, emissions to the environment from the use of plant protection products were determined. The calculated emissions were used to assess the freshwater ecotoxicity potential using the USEtox 2.02 model. It was found that in all soil tillage systems, the largest stream of emissions of active substances to the environment was the amount of substances available for leaching and surface runoff, followed by emissions to air and emissions to groundwater. Herbicides were the main source of emissions from plant protection products used. A greater threat of toxic effects on the freshwater ecosystem was observed on farms producing maize for grain in direct sowing due to the greater use of herbicides than on farms with conventional and reduced tillage.

Effect of Absorption Time for the Preparation of Activated Carbon from Wasted Tree Leaves of Quercus alba and Investigating Life Cycle Assessment

In this article, the effect of absorption time on the surface chemistry and pore structure of activated carbon (AC) from waste leaves of Quercus alba with the H3PO4 chemical activation method. XRD, SEM, EDX, BET, TGA, and FT-IR analyses of prepared AC were used to figure out the properties of the activated carbon. The results demonstrated that the 48 h absorption time of H3PO4 contributed to the highest surface area, 943.2 m2/g, among all the prepared activated carbon samples. As the absorption time of the phosphoric acid activating agent was increased, the surface area initially increased and then started to decrease. The further surface chemical characterization of activated carbon was determined by FT-IR spectroscopic method. Life cycle assessment methodology was employed in order to investigate the environmental impacts associated with the laboratory steps for activated carbon (AC) production. The LCA approach was implemented using OpenLCA 1.10.3 software, while ReCiPe Midpoint (H) was used for environmental impact assessment. The results of the LCA study showed that the impact categories related to toxicity were particularly affected by the utilization of electrical energy (≈90%). The power utilized during laboratory procedures was the main cause of environmental impacts, contributing an average of nearly 70% across all impact categories, with the maximum contribution to the impact category of freshwater ecotoxicity potential (≈97%) and the minimum contribution to land use potential (≈10%).

The impact of organic cotton use and consumer habits in the sustainability of jean production using the LCA approach.

Due to the rise in clothing consumption per person and growing consumer awareness of environmental issues with products, the textile industry must adopt new practices for improving sustainability. The current study thoroughly investigates the benefits of using organic cotton fiber instead of conventional cotton fiber. Because of the extensive use of natural resources in the production of cotton, the primary raw material for textiles, which accounts for the environmental effects of a pair of jeans, a life cycle assessment methodology was used to examine these effects in four different scenarios. The additional scenarios were chosen based on the user preferences for washing temperatures, drying methods, and the type of cotton fiber used in the product. The environmental impact categories of global warming potential, eutrophication potential terrestrial ecotoxicity potential, acidification potential, and freshwater ecotoxicity potential were analyzed by the CML-IA method. The life cycle assessment results revealed that the lowest environmental impacts were obtained for scenario 4 with 100% organic cotton fiber with an improvement of 87% in terrestrial ecotoxicity potential and 59% in freshwater ecotoxicity potential. All of the selected environmental impacts of a pair of jeans are reduced in all scenarios when organic cotton is used. Additionally, consumer habits had a significant impact on all impact categories. Using a drying machine instead of a line dryer during the use phase is just as important as the washing temperature. The environmental impact hotspots for a pair of jeans were revealed to be the eutrophication potential, acidification potential, and global warming potential categories during the use phase, and the terrestrial ecotoxicity potential and freshwater ecotoxicity potential categories during the fabric manufacturing including cotton cultivation. The use of organic cotton as a raw material in manufacturing processes, as well as consumer preferences for washing temperature and drying methods, appears to have significant environmental impacts on a pair of jeans' further sustainable life cycle.

Environmental impacts and optimizing strategies of municipal sludge treatment and disposal routes in China based on life cycle analysis.

The management and utilization of sludge in a sustainable approach require a systematic analysis of the environmental impacts generated from diverse sludge treatment and disposal processes. This study systematically assessed 12 common sludge treatment and disposal routes based on the existing operating and construction conditions of representative sludge disposal projects in China. We evaluated their environmental impacts using a life cycle assessment following the International Organization for Standardization (ISO 14040 and ISO 14044), and found that the routes of co-incineration, mono-incineration, and anaerobic digestion with or without thermal hydrolysis may be useful in terms of simultaneously controlling environmental pollution and carbon emissions in China. Therein, the route of co-incineration was recommended as the best one because its human toxicity potential (-152.31kg dichlorobenzene (1,4-DB) eq/ton dry solid (t DS)), freshwater ecotoxicity potential (FEP, -127.40kg 1,4-DB eq/t DS), terrestrial ecotoxicity potential (TEP, -0.81kg 1,4-DB eq/t DS), and global warming potential (-27.26kg CO2 eq/t DS) were all negative (environmental benefits). Furthermore, the toxicity impacts of the mono-incineration route were also negative, but it still needed to further enhance energy recovery to reduce carbon emissions. Despite the routes of anaerobic digestion and thermal hydrolysis in combination with anaerobic digestion had the excellent negative carbon emission attributes (-572.44kg CO2 eq/t DS, -474.92kg CO2 eq/t DS), they showed serious FEP and TEP owing to the heavy metals pollution caused by subsequent land use of anaerobic digested sludge. Overall, this study selected the most suitable sludge treatment and disposal routes to simultaneously satisfy the requirements of carbon emission reduction and pollution control in China and proposed optimizing suggestions for future technical improvement and development.

Potential Environmental Impacts of Peanut Using Water Footprint Assessment: A Case Study in Georgia

The recent decade has witnessed an increase in irrigated acreage in the southeast United States due to the shift in cropping patterns, climatic conditions, and water availability. Peanut, a major legume crop cultivated in Georgia, Southeast United States, has been a staple food in the American household. Regardless of its significant contribution to the global production of peanuts (fourth largest), studies related to local or regional scale water consumption in peanut production and its significant environmental impacts are scarce. Therefore, the present research contributes to the water footprint of peanut crops in eight counties of Georgia and its potential ecological impacts. The impact categories relative to water consumption (water depletion—green and blue water scarcity) and pesticide use (water degradation—potential freshwater ecotoxicity) using crop-specific characterization factors are estimated for the period 2007 to 2017 at the mid-point level. These impacts are transformed into damages to the area of protection in terms of ecosystem quality at the end-point level. This is the first county-wise quantification of the water footprint and its impact assessment using ISO 14046 framework in the southeast United States. The results suggest inter-county differences in water consumption of crops with higher blue water requirements than green and grey water. According to the water footprint analysis of the peanut crop conducted in this study, additional irrigation is recommended in eight Georgia counties. The mid-point level impact assessment owing to water consumption and pesticide application reveals that the potential freshwater ecotoxicity impacts at the planting and growing stages are higher for chemicals with high characterization factors regardless of lower pesticide application rates. Multiple regression analysis indicates blue water, yield, precipitation, maximum surface temperature, and growing degree days are the potential factors influencing freshwater ecotoxicity impacts. Accordingly, a possible impact pathway of freshwater ecotoxicity connecting the inventory flows and the ecosystem quality is defined. This analysis is helpful in the comparative environmental impact assessments for other major crops in Georgia and aids in water resource management decisions. The results from the study could be of great relevance to the southeast United States, as well as other regions with similar climatic zones and land use patterns. The assessment of water use impacts relative to resource availability can assist farmers in determining the timing and layout of crop planting.

Safe-and-Sustainable-by-Design Framework Based on a Prospective Life Cycle Assessment: Lessons Learned from a Nano-Titanium Dioxide Case Study.

Safe-and-sustainable-by-design (SSbD) is a concept that takes a systems approach by integrating safety, sustainability, and functionality throughout a product’s the life cycle. This paper proposes a framework based on a prospective life cycle assessment for early safety and sustainability assessment. The framework’s purpose is to identify environmental sustainability and toxicity hotspots early in the innovation process for future SSbD applicability. If this is impossible, key performance indicators are assessed. Environmental sustainability aspects, such as global warming potential (GWP) and cumulative energy demand (CED), and toxicity aspects, such as human toxicity potential and freshwater ecotoxicity potential, were assessed upon applying the framework on a case study. The case study regarded using nano-titanium dioxide (P25-TiO2) or a modified nano-coated version (Cu2O-coated/P25-TiO2) as photocatalysts to produce hydrogen from water using sunlight. Although there was a decrease in environmental impact (GWP and CED), the modified nano-coated version had a relatively higher level of human toxicity and freshwater eco-toxicity. For the presented case study, SSbD alternatives need to be considered that improve the photocatalytic activity but are not toxic to the environment. This case study illustrates the importance of performing an early safety and environmental sustainability assessment to avoid the development of toxic alternatives.

Experimental, economic and life cycle assessments of recycling end-of-life monocrystalline silicon photovoltaic modules

The utilization of solar technology for clean energy generation has seen a dramatic increase over the past decade. Eyeing the ever-growing solar capacity and the subsequent inevitable deluge of solar panel wastes, the ideal approach to handle End-of-Life (EoL) solar photovoltaic (PV) panels is to recycle their materials for reuse. This present study explores an optimal recycling process with a high resource recovery efficiency on a laboratory scale, which comprises of three main steps: module delamination, acid etching and sequential electrodeposition. High recoveries of 86, 95 and 97% were achieved for silver, lead and aluminum, respectively. The acquired results are further applied in a life cycle assessment. The process was scaled up to simulate an industrial process and its human and environmental impacts were compared to those of the landfilling disposal method, with six main impact categories analyzed and described: global warming potential, human toxicity potential, freshwater ecotoxicity potential, acidification potential, eutrophication potential and ozone depletion potential. Mitigation strategies are also proposed. Lastly, economic analysis demonstrated that at a treatment capacity of 892.5 kg/h, the process is feasible with an internal revenue rate of 28.2% and a payback time of less than a year, provided the waste collection is subsidized.

Estimation of Eco-Efficiency of Wastewater Management Plants Using the Life Cycle Assessment (LCA) Method

An eco-cost measurement was carried out to see the LCA process stages' efficiency in this study. The LCA process used in the wastewater treatment plant will carry out the steps in the LCA method. The four phases must be carried out correctly to provide good results when making decisions for improvements in each process unit carried out. When carrying out goals and scope, the process determines the goals to be achieved in wastewater management. Environmental impact calculations are carried out using SimaPro software. The nine types defined by the abbreviation are climate change or global warming potential (GWP), freshwater eco-toxicity potential (FETP), freshwater eutrophication potential (FEP), human toxicity potential (HTP), metal depletion potential (MDP), depletion ozone potential (ODP), particulate matter formation (PMF), terrestrial eco-toxicity potential (TETP), and water depletion potential (WDP). The value of the Eco-Efficiency Index (EEI) in the wastewater management installation is 0.183. Meanwhile, the Eco-Efficiency Ratio (EER Rate) value in the installation is -445.81% The total damage assessment resulting from the process is human health (DALY) of 0.00339, ecosystem quality (PDF m2yr) of 874,123 and resources (MJ Surplus) of 5,8234. Then the eco cost value for human health is IDR 4,293,393.642; ecosystem quality is IDR 20,944,494.07; land resources is IDR 409,629. Then the Eco- Efficiency Index (EEI) value in the wastewater management installation is 0.178. Thus the installation can be affordable (financially affordable) and not sustainable (not environmentally friendly) because the eco cost value is greater than the net value of the WWTP.

Life cycle assessment on PERC solar modules

With the pursuit of high photoelectric conversion efficiency in the photovoltaic market, passivated emitter and rear cell (PERC) modules has become the new market mainstream. The environmental impact of PERC modules requires life cycle assessment (LCA) methods to analyze. The SimaPro software was used to calculate the environmental impacts, such as global warming potential (GWP), human toxicity potential – cancer effects (HTP-CE), human toxicity potential-non-cancer effects (HTP-nCE), freshwater ecotoxicity potential (FEcP), freshwater eutrophication potential (FEuP) and abiotic depletion potential (ADP) of mono-facial and bifacial (dual-glass encapsulation and transparent back-sheet encapsulation) PERC modules prepared using 158.75 mm, 166 mm and 210 mm silicon wafers. The rear side gain of a bifacial module increases its electricity generation in the Use stage, and thereby making bifacial module achieve better environmental performance than mono-facial module. In order to improve the rear side gain of bifacial module, it is usually necessary to select an appropriate ground reflective material in system design. The LCA results show that the waterproof membrane TPO (Thermoplastic Polyolefin) is a very good choice, and white gravel and grassland can also be considered in landscape design point of view. Whether to choose dual-glass encapsulation or transparent back-sheet encapsulation, has little effect on the overall environmental impact of bifacial modules. In addition, adding recycling in the photovoltaic industry chain can significantly reduce the overall environmental impact of photovoltaic modules, especially in the indicators such as ADP, HTP-CE and FEuP.

Comparison of life cycle toxicity assessment methods for municipal wastewater treatment with the inclusion of direct emissions of metals, PPCPs and EDCs

The occurrence of various micropollutants such as pharmaceuticals personal care products, endocrine disrupting chemicals (PPCPs/EDCs) and metals in municipal wastewater, and their poor removal efficiencies can lead to toxicity impact on humans, and freshwater and terrestrial ecosystems. Life cycle assessment is an efficient and effective tool to evaluate the environmental impact of wastewater treatment plants, but guidelines for toxicity assessment are lacking due to the complexity. This study aims to evaluate both life cycle inventory by including metals and PEC, and life cycle toxicity assessment (LCIA) methods namely CML-IA, Recipe, USEtox, EDIP 2003 and IMPACT 2002+ in midpoint category with a large centralised wastewater treatment plant in Malaysia as a case study. The removal efficiencies of metals and PPCPs/EDCs in the wastewater ranged from 9% to 99% and no clear patterns were found about occurrence and removal efficiencies of metals and PPCPs/EDCs in developing and developed countries. The inclusion of metals and PPCPs/EDCs in effluent resulted in 76% increase in freshwater ecotoxicity potential (FEP) and 88% increase in terrestrial ecotoxicity potential (TEP) while only 4% increase in human toxicity potential (HTP). The results indicate the importance of including direct emissions such as metals and PPCPs/EDCs even in low-strength municipal wastewater for environmental toxicity assessment. The comparison of five LCIA methods suggests that HTP assessment is more challenging due to inconsistency between five LCIA methods while CML-IA, Recipe, and IMPACT 2002+ achieved consistent human toxicity and ecotoxicity assessment results in the WWTP. The results highlight the importance of sampling and inclusion of metals and PPCPs/EDCs data especially prioritised micropollutants for life cycle toxicity assessment and recommends LCIA methods for ecotoxicity assessment of WWTPs in the current scientific development situation on toxicity studies, which can provide guidance to researchers for life cycle toxicity assessment of wastewater treatment.

Assessment of energy use and environmental impacts of wastewater treatment plants in the entire life cycle: A system meta-analysis

Wastewater treatment plants (WWTPs) play a critical role in the sustainable development of water resources due to its outstanding ability of removing pollutants from complex influent wastewater and generating clean and safe effluent. This paper innovatively adopted the meta-analysis method in view of published LCA studies to assess the energy use and environmental impacts of WWTPs during their life cycle. The search and screening process determined a useful data source with 54 LCA literatures covering 109 relevant case studies. The meta-analysis results revealed that, compared with other regions, the WWTPs in China have the higher intensity in terms of energy use, global warming potential (GWP), eutrophication potential (EP), acidification potential (AP), photochemical oxidation (PHO), freshwater ecotoxicity potential (FETP) and terrestrial ecotoxicity potential (TETP) categories, implying that the energy conservation and emission reduction strategies are necessary to wastewater treatment industry in China. Moreover, compared with A/A/O and CASS processes, the A/O process consumes less energy and results in lower GWP and AP intensity, but affects adversely the natural water-body protection due to undesirable treatment efficiency. Furthermore, the treatment capacities of medium and large scales (i.e. 5-20 × 104 m3/d) are most reasonable sizes for WWTPs since their intensity of energy use, GWP, EP and AP are under a relatively low level. Finally, a strict effluent discharge standard is highly recommended from the perspective of protecting aquatic environment, although it leads to a higher energy consumption. The findings of this study could provide valuable references for promoting healthy and sustainable wastewater treatment industry.

Parameter optimization of environmental technologies using a LCA-based analysis scheme: A bioaugmentation case study

Life cycle assessment (LCA) has proven to be a useful tool in assessing environmental technologies in a retrospective manner. To fully uncover the environmental improvement potential while advancing technologies under technical and environmental constraints, this study recommended approaching the LCA proactively to assess the progress of parameter optimization before determining critical parameters. To that end, the present work introduced a multimethod eight-step (MMES) analysis scheme, which included an integration of LCA with Plackett-Burman multifactorial design, central composite design, and multi-objective optimization. By creating a large number of scenarios through experimental design, we jointly optimized technical efficiency and environmental sustainability, which allowed for the identification of critical parameters that likely had contradictory influences on different objectives. Through a case study concerning the bioaugmentation of constructed wetland (CW), we applied the MMES scheme to optimize the culture conditions of the strain Arthrobacter sp. ZXY-2 for enhanced atrazine removal. The results showed that, by reducing the Na2HPO4·12H2O concentration from 6.5 g/L to 6 g/L in the culture condition, we decreased the freshwater ecotoxicity potential and maintained a high level of atrazine removal. Regarding the production process of microbial inocula, the strain ZXY-2 grown at the optimized culture reduced the total environmental impact from 13% to 50% compared with the original culture and helped the CW exhibit more favorable atrazine-removal performance. Taken together, the case study demonstrated the effectiveness of using the MMES scheme for parameter optimization of environmental technologies. For future development, the MMES scheme should extend the application to more fields and refine uncertainty management.

Environmental sustainability analysis of chitosan microbeads production for pharmaceutical applications via computer-aided simulation, WAR and TRACI assessments

In recent decades, pharmaceutical uses of chitosan microbeads have been identified owing to their low toxicity, biocompatibility and biodegradability. However, many contributions have limited such microbeads preparation to lab-scale and there are no works reported in the literature about the scaling-up of chitosan microbeads production. To fill the knowledge gap, this research attempts to simulate and evaluate the environmental performance of large-scale production of chitosan microbeads under sustainability concept using computer-aided process engineering (CAPE). The extended energy and mass balances were provided by process simulation using the commercial software Aspen Plus ®. The environmental assessment was performed through two computer-aided tools: waste reduction (WAR) algorithm and Tool for the Reduction and Assessment of Chemical and other Environmental Impacts (TRACI). Results reported negatives values for total generation rate of Potential Environmental Impacts (PEI) (−1.16 × 10+2, −9.25 × 10+1, −1.00 × 10+2 and −7.66 × 10+1 PEI/hr) and highest total output rate of PEI for cases 4 and 3 (considering energy flows contributions). For TRACI tool, potential environmental impacts were low, however, the freshwater ecotoxicity potential for freshwater emissions was higher (6.03E+02 CTUeco/hr) than for natural soil emissions (1.55E+02 CTUeco/hr). These results showed good environmental performance of the process and can be used as a benchmark in the production of more environmental-friendly chitosan microbeads at large-scale.

Inventory and life cycle assessment of an Italian automotive painting process

In the current context of the European Environmental legislation and standards, the automotive sector is expected to continuously improve the vehicles life cycle with solutions able to minimise emissions of greenhouse gases and other negative effects on the environment and on human health. The vehicle painting process has been identified to be responsible of significant potential impacts, but recent primary inventory data and impact results are currently scarcely available in the literature. The novelty of this paper is the provision of a comprehensive life cycle inventory and life cycle assessment (LCA) of a painting process, with reference to a large and highly automated plant located in Turin (Italy). To achieve these goals, the highly recognised methodology of LCA has been followed, as indicated in ISO 14040-44. A detailed inventory is disclosed (both as input/output table and ILCD file) for the four main phases of the painting process (electrodeposition, primer application, top coat application and final drying and revision). Impact results on the categories of climate change, acidification, terrestrial eutrophication and photochemical ozone creation potential are quantified as well. These latter show that the major hot points are the high-energy consumption (specifically, the integrated provision of technological heating and chilled water is responsible of almost half of the total emissions of greenhouse gases), the direct emission of volatile organic compounds into air (for a total of 7.44 kg/car) and the waste production and treatment [giving a significant contribution to the impact categories of ozone depletion (99%), freshwater eutrophication (66%) and freshwater ecotoxicity potential (60%)]. This study contributes to increase the pool of publicly available life cycle data for specific applications in the automotive sector. In addition, the easy replicability and adaptation of the provided inventory is expected to boost enterprises to increase their overall sustainability. Finally, this study provides data and tools for the development of further research in alternative painting technologies.

Freshwater ecotoxicity assessment of pesticide use in crop production: Testing the influence of modeling choices

Pesticides help to control weeds, pests, and diseases contributing, therefore, to food availability. However, pesticide fractions not reaching the intended target may have adverse effects on the environment and the field ecosystems. Modeling pesticide emissions and the link with characterizing associated impacts is currently one of the main challenges in Life Cycle Assessment (LCA) of agricultural systems. To address this challenge, this study takes advantage of the latest recommendations for pesticide emission inventory and impact assessment and frames a suitable interface for those LCA stages and the related mass distribution of pesticide avoiding a temporal overlapping. Here, freshwater ecotoxicity impacts of the production of feed crops (maize, grass, winter wheat, spring barley, rapeseed, and peas) in Denmark were evaluated during a 3-year period, testing the effects of inventory modeling and the recent updates of the characterization method (USEtox). Potential freshwater ecotoxicity impacts were calculated in two functional units reflecting crop impact profiles per ha and extent of cultivation, respectively. Ecotoxicity impacts decreased over the period, mainly because of the reduction of insecticides use (e.g., cypermethrin). Three different emission modeling scenarios were tested; they differ on the underlining assumptions and data requirements. The main aspects influencing impact results are the interface between inventory estimates and impact assessment, and the consideration of intermedia processes, such as crop growth development and pesticide application method. Impact scores for AS2 were higher than RS and AS1, but the differences in the crops ranking was less apparent. On the other hand, the influence on the estimation of impacts for individual AIs was considerable and statistical differences were found in the impact results modeled in scenarios RS and AS2. Thereby indicating the effect of inventory models on ecotoxicity impact assessment.

Life cycle environmental impacts of advanced wastewater treatment techniques for removal of pharmaceuticals and personal care products (PPCPs)

Pharmaceutical and personal care products (PPCPs) are of increasing interest because of their ecotoxicological properties and environmental impacts. Wastewater treatment plants (WWTPs) are the main pathway for their release into freshwaters due to the inefficiency of conventional WWTPs in removing many of these contaminants from effluents. Therefore, different advanced effluent treatment techniques have been proposed for their treatment. However, it is not known at present how effective these treatment methods are and whether on a life cycle basis they cause other environmental impacts which may outweigh the benefits of the treatment. In an effort to provide an insight into this question, this paper considers life cycle environmental impacts of the following advanced treatment techniques aimed at reducing freshwater ecotoxicity potential of PPCPs: granular activated carbon (GAC), nanofiltration (NF), solar photo-Fenton (SPF) and ozonation. The results suggest that on average NF has the lowest impacts for 13 out of 18 categories considered. GAC is the best alternative for five impacts, including metals and water depletion, but it has the highest marine eutrophication. SPF and ozonation are the least sustainable for eight impacts, including ecotoxicity and climate change. GAC and NF are also more efficient in treating heavy metals while avoiding generation of harmful by-products during the treatment, thus being more suitable for potable reuse of wastewater. However, releasing the effluent without advanced treatment to agricultural land achieves a much higher reduction of freshwater ecotoxicity than treating it by any of the advanced treatments and releasing to the environment. Therefore, the use of advanced effluent treatment for agricultural purposes is not recommended.