Challenges in Life Cycle Assessment: An Overview of Current Gaps and Research Needs

Exploring Environmental and Cardiometabolic Impacts Associated with Adherence to the Sustainable EAT-Lancet Reference Diet: Findings from the China Health and Nutrition Survey

BACKGROUND

To contribute to the growing evidence on the potential co-benefits of the EAT-Lancet reference diet for cardiometabolic health and sustainability, we investigated this topic in a nationwide prospective cohort of Chinese adults. Adherence to this diet has been measured using several indices, including the World Index for Sustainability and Health (WISH) and the Planetary Health Diet Index (PHDI).

OBJECTIVES

We aimed to investigate the associations between adherence to the EAT-Lancet reference diet, as evaluated by WISH and PHDI, with risk of new-onset cardiometabolic diseases (CMDs), risk of all-cause mortality, and greenhouse gas (GHG) emissions.

METHODS

We included adults (n = 14,652 for CMDs and 15,318 for all-cause mortality) from the China Health and Nutrition Survey (1997-2015) in the analysis. Dietary intake data were collected, and WISH and PHDI scores were computed with established methods. CMDs included myocardial infarction (MI), type 2 diabetes mellitus (T2DM), and stroke. We used Cox proportional hazard regression models to analyze data with a mean of 10 years of follow-up from the date of baseline to the end of study or until the occurrence of the event of interest, whichever came first. We adjusted for sociodemographic, anthropometric, lifestyle, and dietary characteristics of participants as confounders.

RESULTS

Greater adherence to the EAT-Lancet reference diet, as reflected by higher WISH or PHDI scores, was inversely associated with risk of MI {Q4 vs. Q1: hazard ratio  ( HR ) = 0.68 [95% confidence interval (CI): 0.48, 0.96] for WISH and 0.14 (95% CI: 0.07, 0.29) for PHDI}, T2DM [Q4 vs. Q1: HR = 0.81 (95% CI: 0.67, 0.96) for WISH and 0.68 (95% CI: 0.57, 0.82) for PHDI], and all-cause mortality [Q4 vs. Q1: HR = 0.80 (95% CI: 0.68, 0.95) for WISH and 0.60 (95% CI: 0.46, 0.80) for PHDI] in fully adjusted models (all p -trend < 0.05 ). Both WISH and PHDI were inversely associated with GHG emissions in fully adjusted models (all p -trend < 0.05 ). WISH and PHDI were not significantly associated with risk of stroke.

CONCLUSIONS

Our findings supported the co-benefits of the EAT-Lancet reference diet for both cardiometabolic health and environmental sustainability. Long-term adherence to this reference diet as effectively indicated by either higher WISH or PHDI scores may reduce the risk and burden of CMDs and all-cause mortality in Chinese adults. https://doi.org/10.1289/EHP15006.

Life Cycle Assessment in a Nutshell-Best Practices and Status Quo for the Plastic Sector

Life cycle assessment (LCA) is an internationally standardized methodology to evaluate the potential environmental impacts of products and technologies and assists in lowering their negative environmental consequences. So far, extensive knowledge of LCA-their application and interpretation-is restricted to experts. However, the importance of LCA is increasing due to its application in business, environmental, and policy decision-making processes. Therefore, general knowledge of LCA is critically important. The current work provides an introduction to LCA for non-experts discussing important steps and aspects and therefore can be used as a starting point for LCA. In addition, a comprehensive checklist for non-experts with important content and formal aspects of LCA is provided. Specific aspects of LCA for the plastics sector along the value chain are also discussed, including their limitations.

Accounting for land use changes beyond the farm-level in sustainability assessments: The impact of cocoa production

Impact assessments are used to raise evidence and guide the implementation of sustainability strategies in commodity value chains. Due to methodological and data difficulties, most assessments of agricultural commodities capture the impacts occurring at the farm-level but often dismiss or oversimplify the impacts caused by land use dynamics at larger geographic scale. In this study we analyzed the impacts of two cocoa production systems, full-sun and agroforestry, at the farm-level and beyond the farm-level. We used life cycle assessment to calculate the impacts at the farm-level and a combination of land use modelling with spatial analysis to calculate the impacts beyond the farm-level. We applied this to three different future cocoa production scenarios. The impacts at the farm-level showed that, due to lower yields, cocoa agroforestry performs worse than cocoa full-sun for most impact indicators. However, the impacts beyond the farm-level showed that promoting cocoa agroforestry in the landscape can bring the largest gains in carbon and biodiversity. A scenario analysis of the impacts at the landscape-level showed large nuances depending on the cocoa farming system adopted, market dynamics, and nature conservation policies. The analysis indicated that increasing cocoa demand does not necessarily result in negative impacts for carbon stocks and biodiversity, if sustainable land management and sustainable intensification are adopted. Landscape-level impacts can be larger than farm-level impacts or show completely opposite direction, which highlights the need to complement farm-level assessments with assessments accounting for land use dynamics beyond the farm-level.

Environmental Impacts of Pig and Poultry Production: Insights From a Systematic Review

Pig and poultry production systems have reached high-performance levels over the last few decades. However, there is still room for improvement when it comes to their environmental sustainability. This issue is even more relevant due to the growing demand for food demand since this surplus food production needs to be met at an affordable cost with minimum impact on the environment. This study presents a systematic review of peer-reviewed manuscripts that investigated the environmental impacts associated with pig and poultry production. For this purpose, independent reviews were performed and two databases were constructed, one for each production system. Previous studies published in peer-reviewed journals were considered for the databases if the method of life cycle assessment (LCA) was applied to pig (pork meat) or poultry (broiler meat or table eggs) production to estimate at least the potential effects of climate change, measured as CO₂-eq. Studies considering the cradle-to-farm gate were considered, as well as those evaluating processes up to the slaughterhouse or processor gate. The pig database comprised 55 studies, while 30 publications were selected for the poultry database. These studies confirmed feeding (which includes the crop cultivation phase, manufacturing processes, and transportation) as the main contributor to the environmental impact associated with pig and poultry production systems. Several studies evaluated feeding strategies, which were indicated as viable alternatives to mitigate the environmental footprint associated with both production chains. In this study, precision feeding techniques are highlighted given their applicability to modern pig and poultry farming. These novel feeding strategies are good examples of innovative strategies needed to break paradigms, improve resource-use efficiency, and effectively move the current productive scenario toward more sustainable livestock systems.

Integrating endocrine-related health effects into comparative human toxicity characterization

Endocrine-disrupting chemicals have the ability to interfere with and alter functions of the hormone system, leading to adverse effects on reproduction, growth and development. Despite growing concerns over their now ubiquitous presence in the environment, endocrine-related human health effects remain largely outside of comparative human toxicity characterization frameworks as applied for example in life cycle impact assessments. In this paper, we propose a new methodological framework to consistently integrate endocrine-related health effects into comparative human toxicity characterization. We present two quantitative and operational approaches for extrapolating towards a common point of departure from both in vivo and dosimetry-adjusted in vitro endocrine-related effect data and deriving effect factors as well as corresponding characterization factors for endocrine-active/endocrine-disrupting chemicals. Following the proposed approaches, we calculated effect factors for 323 chemicals, reflecting their endocrine potency, and related characterization factors for 157 chemicals, expressing their relative endocrine-related human toxicity potential. Developed effect and characterization factors are ready for use in the context of chemical prioritization and substitution as well as life cycle impact assessment and other comparative assessment frameworks. Endocrine-related effect factors were found comparable to existing effect factors for cancer and non-cancer effects, indicating that (1) the chemicals' endocrine potency is not necessarily higher or lower than other effect potencies and (2) using dosimetry-adjusted effect data to derive effect factors does not consistently overestimate the effect of potential endocrine disruptors. Calculated characterization factors span over 8-11 orders of magnitude for different substances and emission compartments and are dominated by the range in endocrine potencies.

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.

Comparative Life Cycle Assessment of Advanced Wastewater Treatment Processes for Removal of Chemicals of Emerging Concern

The potential health effects associated with contaminants of emerging concern (CECs) have motivated regulatory initiatives and deployment of energy- and chemical-intensive advanced treatment processes for their removal. This study evaluates life cycle environmental and health impacts associated with advanced CEC removal processes, encompassing both the benefits of improved effluent quality as well as emissions from upstream activities. A total of 64 treatment configurations were designed and modeled for treating typical U.S. medium-strength wastewater, covering three policy-relevant representative levels of carbon and nutrient removal, with and without additional tertiary CEC removal. The USEtox model was used to calculate characterization factors of several CECs with missing values. Stochastic uncertainty analysis considered variability in influent water quality and uncertainty in CEC toxicity and associated characterization factors. Results show that advanced tertiary treatment can simultaneously reduce nutrients and CECs in effluents to specified limits, but these direct water quality benefits were outweighed by even greater increases in indirect impacts for the toxicity-related metrics, even when considering order-of-magnitude uncertainties for CEC characterization factors. Future work should consider water quality aspects not currently captured in life cycle impact assessment, such as endocrine disruption, in order to evaluate the full policy implications of the CEC removal.

Biodiversity impact assessment (BIA+) - methodological framework for screening biodiversity

For the past 20 years, the life cycle assessment (LCA) community has sought to integrate impacts on biodiversity into the LCA framework. However, existing impact assessment methods still fail to do so comprehensively because they quantify only a few impacts related to specific species and regions. This paper proposes a methodological framework that will allow LCA practitioners to assess currently missing impacts on biodiversity on a global scale. Building on existing models that seek to quantify the impacts of human activities on biodiversity, the herein proposed methodological framework consists of 2 components: a habitat factor for 14 major habitat types and the impact on the biodiversity status in those major habitat types. The habitat factor is calculated by means of indicators that characterize each habitat. The biodiversity status depends on parameters from impact categories. The impact functions, relating these different parameters to a given response in the biodiversity status, rely on expert judgments. To ensure the applicability for LCA practitioners, the components of the framework can be regionalized on a country scale for which LCA inventory data is more readily available. The weighting factors for the 14 major habitat types range from 0.63 to 1.82. By means of area weighting of the major habitat types in a country, country-specific weighting factors are calculated. In order to demonstrate the main part of the framework, examples of impact functions are given for the categories "freshwater eutrophication" and "freshwater ecotoxicity" in 1 major habitat type. The results confirm suitability of the methodological framework. The major advantages are the framework's user-friendliness, given that data can be used from LCA databases directly, and the complete inclusion of all levels of biodiversity (genetic, species, and ecosystem). It is applicable for the whole world and a wide range of impact categories. Integr Environ Assess Manag 2018;14:282-297. © 2017 SETAC.