Learnings from LCA-based methods: should chemicals in food packaging be a priority focus to protect human health?

Abstract

Given the scale and variety of human health damage (HHD) caused by food systems, prioritization methods are urgently needed. In this study HHD is estimated for case studies on red meat and sugary sweetened beverages (SSB) packaged in high-impact polystyrene (HIPS) due to various relevant health impacts. Specifically, we aim to asses if chemicals in food packaging are important to HHD in a life cycle context. The functional unit is "daily consumption of a packaged food per person in the United States." Method developments focus on human toxicity characterization of chemicals migrating from packaging into food. Chemicals and their concentrations in HIPS were identified from regulatory lists. A new high-throughput model estimated migration into food, depending on properties of chemicals, packaging, food, and scenario, and HHD was extrapolated following LCA characterization methods. An LCA-based study on the packaged foods estimated HHD from particulate matter and chemical emissions. Finally, the HHD of consumption of red meat and SSB above the minimum risk level was estimated using novel methods by Stylianou et al. 2016 based on the Global Burden of Disease studies. Results indicate that impacts caused by consumption of food items over minimum risk are high priority for mitigating HHD, as well as associated PM2.5 emissions from agriculture. Impacts due to the chemicals migrating from HIPS into food were minor given the study’s assumptions, limitations, and methods. However, calculating the HHD for migration levels at the legally allowable limits resulted in impacts three orders of magnitude greater than impacts from the assumed chemical concentrations, and thus a relevant contributor to HHD. Future work is required to quantify realistic exposure to chemicals in packaging and their potential effects in order to elucidate significance in a life cycle context. Understanding toxicity risks posed by simultaneous exposure to several chemicals at one time, all of which are below safety thresholds, requires cross-fertilization with risk and toxicity research. Lastly, the methods developed are a first step towards operationalizing LCA for practitioners to ensure that minimizing impacts on the environment and resources due to food packaging design choices do not lead to unintended health risks caused by chemicals in packaging, and vice versa that minimizing exposure to hazardous chemicals do not increase environmental damages.