Prioritizing Organic Pollutants for Shale Gas Exploitation: Life Cycle Environmental Risk Assessments in China and the US.

Environmental impacts associated with shale gas exploitation have been historically underestimated due to neglecting to account for the production or the release of end-of-pipe organic pollutants. Here, we assessed the environmental impacts of shale gas production in China and the United States using life cycle assessment. Through data mining, we compiled literature information on organic pollutants in flowback and produced water (FPW), followed by assessments using USEtox to evaluate end-of-pipe risks. Results were incorporated to reveal the life cycle risks associated with shale gas exploitation in both countries. China exhibited higher environmental impacts than the US during the production phase. Substantially different types of organic compounds were observed in the FPW between two countries. Human carcinogenic and ecological toxicity attributed to organics in FPW was 3 orders of magnitude higher than that during the production phase in the US. Conversely, in China, end-of-pipe organics accounted for approximately 52%, 1%, and 47% of the overall human carcinogenic, noncarcinogenic, and ecological impacts, respectively. This may be partially limited by the quantitative data available. While uncertainties exist associated with data availability, our study highlights the significance of integrating impacts from shale gas production to end-of-pipe pollution for comprehensive environmental risk assessments.

Use, reuse, and waste management of single-use products associated with the COVID-19 pandemic in the United States.

Single-use product usage is not a new concern. However, during the early stages of the COVID-19 pandemic, the use and disposal of single-use products, especially those related to managing the pandemic, rose to prominence. Reports of shortages-and at the same time litter formation arising from improper disposal of various pandemic-related materials such as gloves, masks, wipes, and food takeout containers-were frequently relayed. To address shortages, it was recommended that single-use products be reused in some instances. As these recommendations were widely adopted, it became essential to assess consumer preferences regarding single-use product usage. Aiming to fill that void, a survey was distributed to learn about single-use product usage, possible reuse of single-use products, and waste-management practices during the COVID-19 pandemic in the US. Respondents preferred reusable fabric masks followed by disposable surgical masks. A significant percentage of respondents answered that they would reuse a disposable mask and mostly selected rotating masks as the preferred "disinfection" method in between the reuse of single-use masks. Gloves were not used by most respondents whereas wipes and/or paper towels were used by more than half of respondents. Free-response answers were analyzed for common themes. Concerns related to pandemic-related product use and disposal, and food packaging or food preparation were observed in the free-response answers. This survey reveals that respondents perceived changes in their consumption and waste generation or perceived a change in the type of products consumed and discarded due to the pandemic. Overall, respondents expressed a preference for reuse and a concern over the increase in single-use products. Results of this study can be used to make projections on the consumption and reuse of single-use products in crisis scenarios. In addition, the data can be used to model the use and disposal phase in single-use product life-cycle assessments. Integr Environ Assess Manag 2024;00:1-11. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Cradle-to-grave environmental impact assessment of silver enabled t-shirts: Do nano-specific impacts exceed non nano-specific emissions?

Consumption of silver nanoparticles (nAg) is increasing due to their use in various industries. A comprehensive analysis is needed to elucidate the potential environmental and human health benefits and costs of the silver-enabled consumer products. For this purpose, four commercially available silver/nanosilver enabled polyester textiles with different initial silver/nanosilver loadings (1.07-4030 µg Ag/g textile) are included in the current research and cradle-to-grave life cycle assessments (LCA) are conducted to identify hotspots associated with production and use of these products throughout their lifetimes (100 cycles). Both non nano-specific and nano-specific impacts are calculated using nano-specific ecotoxicity characterization factors for nAg, instead of the commonly utilized ionic silver (Ag+) surrogate. Additionally, four different laundering scenarios were modeled to analyze the impacts resulting from using conventional and high efficiency machines. In the majority of environmental impact categories, either polyester textile manufacturing (regardless of Ag/nAg enabling) or laundering were identified as hotspots. Non nano-specific ecotoxicity impacts ranged from 1.58 × 101-2.91 × 101 CTUe/textile (CTUe: comparative toxic units for ecosystems) and nano-specific ecotoxicity impacts ranged from 2.01 × 10-4-3.10 × 10-3 CTUe/textile for the lowest and the highest Ag/nAg containing textiles, respectively. It is also found that unless the initial silver loading per textile is significantly high (in this case 4030 µg Ag/g textile comparing to the lowest load of 1.07 µg Ag/g textile), ecotoxicity and human health impacts of released silver species would be lower than ecotoxicity and human health impacts resulting from raw materials acquisition and manufacturing of the antibacterial textiles.

Life Cycle Assessment of Struvite Precipitation from Anaerobically Digested Dairy Manure: A Wisconsin Perspective.

Recovering valuable nutrients (e.g., P and N) from waste materials has been extensively investigated at the laboratory scale. Although it has been shown that struvite precipitation from several manure sources contributes to nutrient management practices by recovering valuable nutrients and preventing them from reaching water bodies, it has not been widely applied in commercial (i.e., farm) scales. The purpose of this study is to evaluate the potential environmental impacts of the struvite recovery process from the liquid portion of the anaerobically digested dairy cow manure generated in Wisconsin, USA, dairy farms using life cycle assessment methodology for both bench- and farm-scale scenarios. The struvite precipitation process involves the use of additional chemicals and energy; therefore, investigating upstream impacts is crucial to evaluate the environmental costs and benefits of this additional treatment process. Results indicate that up to a 78% impact decrease in eutrophication potential can be achieved when P and N are recovered in the form of struvite and are applied in lieu of conventional fertilizers, rather than using the liquid portion of the anaerobically digested dairy manure as a fertilizer. Additionally, significant differences are identified in the majority of environmental impact categories when the struvite precipitation process is modeled and evaluated in a farm-scale setting. Future work should expand to evaluate the overall environmental impacts and trade-offs of struvite recovery application, including the anaerobic digestion system itself at the farm scale. Integr Environ Assess Manag 2021;17:292-304. © 2020 SETAC.

A citizen science approach estimating titanium dioxide released from personal care products.

Titanium dioxide (TiO2) is a common component in personal care products (PCP), which through use enters the wastewater treatment plant (WWTP) and ultimately the environment. A citizen science approach is utilized here to inform the prevalence and usage of TiO2 containing PCP on a household scale, which generates information as to the quantity of TiO2 entering the WWTP, and the portion ultimately discharged to the environment. Meanwhile, citizen science sourced inventories were generated to estimate the quantity of TiO2, and potentially nanoscale TiO2 entering the WWTP from consumer products and to determine which products had the greatest contribution. The estimated values were compared with water samples from the WWTP which quantified the amount of total titanium present using ICP-AES. These values were at a similar level with other top-down estimation approaches and suggest that a citizen science approach is valid to estimate the loading of TiO2, and potentially other emerging contaminants, while at the same time engaging with community stakeholders.

Global Warming Impacts of Residential Electricity Consumption: Agent-Based Modeling of Rooftop Solar Panel Adoption in Los Angeles County, California.

Solar photovoltaics (PV) are a renewable electricity technology with lower carbon dioxide equivalent (CO2 e) impacts compared to fossil electricity, making it a technology of interest with respect to combatting global climate change. This paper combines agent-based modeling (ABM) with life cycle assessment (LCA) to simulate rooftop solar PV adoption in Los Angeles (LA) County from 2018-2050 and generate CO2 e impact data at the societal level to compare PV and grid electricity. With respect to solar PV panels, consumer adoption is the "pull" that moves the system and corresponding life cycle CO2 e impacts forward. ABM is used to evaluate the impact of policies and evolutions in technology regarding the adoption of solar PV. Life cycle assessment is used to quantify the life cycle CO2 e impacts of solar PV (including raw materials, manufacturing, and use). The results show that scenarios that increase PV adoption also increase the CO2 e impacts from solar PV use in the short term, due to the raw materials and manufacturing portions of the life cycle. Yet, in the long term, adoption of solar PV may provide CO2 e impact savings from offsetting grid electricity (although this is dependent on the carbon intensity of the electricity sources). The CO2 e impacts of solar panels are dominated by the raw materials and manufacturing phases on a product level basis, but the use phase contributes to the majority of environmental impact savings from an adoption and societal-level perspective. Future work may apply the methodology to other locations in the United States to evaluate if solar panels are an advantageous electricity source compared to the environmental impacts of the electricity grid. Integr Environ Assess Manag 2020;16:1008-1018. © 2020 SETAC.

Estimating human exposure to titanium dioxide from personal care products through a social survey approach.

Titanium dioxide (TiO2 ) has been widely applied in personal care products (PCPs), with up to 36% of TiO2 in PCPs is present at the nanoscale. Due to the large quantity produced and the wide application of TiO2 , there is a great potential for human exposure through various routes and therefore a great potential to elicit adverse impacts. This work utilizes a social survey to generate information and estimate TiO2 (bulk and nanoparticle [NP]) exposure to individuals through the daily use of PCPs. Households in the Madison, Wisconsin, USA metropolitan area were surveyed about their PCP usage. Survey results were then combined with usage patterns and TiO2 content in each PCP category to estimate human exposures. Results indicate sunscreen and toothpaste are major contributors to TiO2 dermal exposure. The estimated daily dermal route of exposure ranges from 2.8 to 21.4 mg TiO2 per person per day. Toothpaste has the potential to be ingested though the oral route; 0.15 to 3.9 mg TiO2 per day were estimated to be ingested when 10% toothpaste ingestion was assumed. The results generated in the present case study are generalizable in predicting individual TiO2 exposure from PCPs when the usage pattern is available. In addition, this study can be further used for risk assessment and to refine the use of TiO2 in PCPs. Integr Environ Assess Manag 2019;00:1-7. © 2019 SETAC.

Sustainable Seafood and Vegetable Production: Aquaponics as a Potential Opportunity in Urban Areas.

Global population growth will increase pressures on current food systems in order to supply adequate protein and produce to the increasingly urban world population. The environmental impact of food production is a critical area of study as it influences water and air quality, ecosystem functions, and energy consumption. Aquaponics (in which seafood and vegetables are grown in a closed-loop system) has the potential to reduce the environmental impact of food production. A review of the current environmental and economic considerations is provided in order to identify current research gaps. Research gaps exist with respect to 1) diversity of aquatic and plant species studied; 2) inconsistent bounds, scope, and lifetime across studies; 3) diverse allocation of the environmental and economic impacts to the coproducts; 4) scale of systems considered; 5) transportation of produced food; and 6) presence of heavy metals, pests, and pathogens with human health implications. These aspects require increased attention to close the existing gaps prior to widescale deployment of these systems for increased sustainable food production toward satisficing human needs. Integr Environ Assess Manag 2019;00:1-12. © 2019 SETAC.

Life Cycle Impact of Titanium Dioxide Nanoparticle Synthesis through Physical, Chemical, and Biological Routes.

The sustainable manufacturing of nanoparticles (NPs) has become critical to reduce life cycle energy use and the associated environmental impact. With the ever-growing production volume, titanium dioxide (TiO2) NPs have been produced through various synthesis routes with differing input materials and reactions, which result in differential reactivity, crystallinity, surface areas, and size distributions. In this study, life cycle assessment is used to analyze and compare the environmental impact of TiO2 NPs produced via seven routes covering physical, chemical, and biological syntheses. The synthesis routes are chosen to represent mainstream NP manufacturing and future trends. Mass-, surface area-, and photocatalytic reactivity-based functional units are selected to evaluate the environmental impact and reflect the corresponding changes. The results show that impact associated with the upstream production of different precursors are dominant for the chemical route. Compared to the chemical route, the physical route requires substantial quantities of supporting gas and high-energy inputs to maintain high temperature; therefore, a higher environmental burden is generated. A high environmental burden is also modeled for the biological route due to the required bacterial culture media. This present study aims to identify the most efficient synthesis route for TiO2 NP production, lower the potential environmental impact, and improve green synthesis and sustainability.

Nanosilver-Enabled Food Storage Container Tradeoffs: Environmental Impacts Versus Food Savings Benefit, Informed by Literature.

Globally, thousands of tons of food are lost each year due to spoilage and degraded quality. This loss is a current critical issue that must be addressed to ensure adequate food supply for the growing world population; the use of technology and regulatory practices are avenues to a solution. One considered approach is the reduction of the microorganism population on the surface of food products to delay spoilage through the use of antimicrobials. One current method is the use of the antimicrobial properties of nanoscale silver (nAg) particles to prolong the freshness of stored food by reducing the bacteria present. Nanoscale silver-enabled food storage containers present a potential solution to the food loss problem; nevertheless, their environmental and human health effects have been questioned by the scientific community. Literature is used to generate data for the life cycle impact assessment of these types of products and their corresponding environmental effects. The benefits of nAg-enabled food storage containers are considered with respect to their potential to extend the shelf life of stored food and prevent food spoilage. The results illustrate that the environmental effects of nano-enabling food storage containers with silver is small (when the initial silver concentration is relatively low, less than 1% by mass) compared with the overall environmental effects of food storage containers and also relatively small compared with the environmental effects of producing the stored food. This finding suggests that the added environmental burden of nano-enabling food storage containers may be small when compared with the environmental burden of food losses. Integr Environ Assess Manag 2018;14:769-776. © 2018 SETAC.

Life Cycle Payback Estimates of Nanosilver Enabled Textiles under Different Silver Loading, Release, And Laundering Scenarios Informed by Literature Review.

Silver was utilized throughout history to prevent the growth of bacteria in food and wounds. Recently, nanoscale silver has been applied to consumer textiles (nAg-textiles) to eliminate the prevalence of odor-causing bacteria. In turn, it is proposed that consumers will launder these items less frequently thus, reducing the life cycle impacts. While previous studies report that laundering processes are associated with the greatest environmental impacts of these textiles, there is no data available to support the proposed shift in consumer laundering behavior. Here, the results from a comprehensive literature review of nAg-textile life cycle studies are used to inform a cradle-to-grave life cycle impact assessment. Rather than assuming shifts in consumer behavior, the impact assessment is conducted in such a way that considers all laundering scenarios to elucidate the potential for reduced laundering to enable realization of a net life cycle benefit. In addition to identifying the most impactful stages of the life cycle across nine-midpoint categories, a payback period and uncertainty analysis quantifies the reduction in lifetime launderings required to recover the impacts associated with nanoenabling the textile. Reduction of nAg-textile life cycle impacts is not straightforward and depends on the impact category considered.