Towards a more comprehensive life cycle assessment framework for assessing toxicity-related impacts for livestock products: The case of Danish pork

Life cycle assessment of hybrid alkali-activated cement production with red mud as an alkali activator

The production of hybrid alkali-activated cement (HAAC) has generated considerable interest in environmental issues. In this research, the environmental impacts of utilizing red mud (RM) as a partial activator of alkali-activated ground granulated blast furnace slag (GBFS) in HAAC production have been evaluated. A contribution analysis was carried out using life cycle assessment (LCA) to assess the environmental significance of six important substances in HAAC production. A comparative analysis of the environmental consequences of producing ordinary portland cement (OPC) and two HAACs using various activators in the same plant was conducted. The results showed that the calcination and preparation of alkali-activated cementitious materials are the two processes with the highest environmental impacts. Marine ecotoxicity was identified as the primary impact category, followed by freshwater ecotoxicity and fossil depletion. HAAC provides better benefits than OPC in most environmental impact categories. Additionally, the inclusion of RM as a partial alkali activator to HAAC results in even more pronounced environmental benefits when compared to NaOH alone, particularly in terms of cleaner production areas.

Residues of veterinary drugs and heavy metal contamination in livestock and poultry meat from Hunan Province, China

Livestock and poultry meat consumption play an important role in the dietary structure of Chinese residents. However, the extent of residues of veterinary drugs and heavy metal contamination in livestock and poultry meat and their by-products within Hunan province is not extensively studied. This survey aimed to fill this gap by assessing the presence of 76 veterinary drug residues in Hunan province. Additionally, heavy metals in pork and pig liver were also assessed. The obtained findings suggest that residues of veterinary drugs are still present in livestock and poultry meat, as well as their by-products, within Hunan province. However, the contamination of heavy metals remained within the food safety limits. These results underscore the significance of establishing more refined criteria for assessing human exposure, taking into account factors such as consumption patterns, product varieties and chemical compounds of interest.

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.

Life cycle assessment perspective on waste resource utilization and sustainable development: A case of glyphosate production

The growing demand for pesticide manufacturing and increasing public awareness of sustainable development, have let to urgent requirements for a refined environmental management framework. It is imperative to conduct process-based life cycle assessments (LCAs) to promote clean and environment-friendly technologies. Herein, the cradle-to-gate LCA of glyphosate production was executed as an example to investigate crucial production factors (materials or energy) and multiple environmental impacts during the production processes. Results showed that methanol caused the highest environmental damage in terms of toxicity, with a normalized value of 85.7 × 10-8, followed by coal-fired electricity in 6.00 × 10-8. Furthermore, optimized schemes were proposed, including energy improvement (electricity generated by switching from coal-fired power to solar power) and wastewater targeted conversion. Regarding the normalization results before and after optimization, the latter showed more significant results with the normalized value decreasing by 21.10 × 10-8, while that of the former only decreased by 6.50 × 10-8. This study provides an integrated LCA framework for organophosphorus pesticides (OPs) from upstream control and offers an important supplement to managing the key pollution factors and control links of the OP industry. Moreover, it reveals the positive influence of optimized schemes in facilitating cleaner production technologies, thus ultimately promoting new methodologies for resource recycling.

Considering degradation kinetics of pesticides in plant uptake models: proof of concept for potato

BACKGROUND

Degradation kinetics of pesticides in plants are crucial for modeling mechanism-based pesticide residual concentrations. However, due to complex open-field conditions that involve multiple pesticide plant uptake and elimination processes, it is difficult to directly measure degradation kinetics of pesticides in plants. To address this limitation, we proposed a modeling approach for estimating degradation rate constants of pesticides in plants, using potato as a model crop. An operational tool was developed to backward-estimate degradation rate constants, and three pesticides were selected to perform example simulations.

RESULTS

The simulation results of thiamethoxam indicated that the growth dynamics of the potato had a significant impact on the degradation kinetic estimates when the pesticide was applied during the early growth stage, as the size of the potato determined the uptake and elimination kinetics via diffusion. Using mepiquat, we demonstrated that geographical variations in weather conditions and soil properties led to significant differences in the dissipation kinetics in both potato plants and soil, which propagated the variability of the degradation rate constant. Simulation results of chlorpyrifos differed between two reported field studies, which is due to the effect of the vertical distribution of the residue concentration in the soil, which is not considered in the majority of recent studies.

CONCLUSIONS

Our proposed approach is adaptable to plant growth dynamics, preharvest intervals, and multiple pesticide application events. In future research, it is expected that the proposed method will enable region-specific inputs to improve the estimation of the degradation kinetics of pesticides in plants. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Framework for defining pesticide maximum residue levels in feed: applications to cattle and sheep

BACKGROUND

Pesticide residues in animal feed can endanger animal health and compromise the safety of livestock products for human consumption. Even though policymakers such as the European Union and the World Health Organization have established maximum residue levels (MRLs) for pesticides in both human food and animal feed, there is no systematic management of pesticides in animal feed that considers the entire supply chain. In response, we propose a framework for defining consistent MRLs for pesticides in animal feed that assesses the impact of defined MRLs on upstream (e.g., MRLs in feed crops) and downstream (e.g., MRLs in livestock products) sectors of the livestock-product supply chain.

RESULTS

The MRLs determined for the selected pesticides in the feed of cattle and sheep as case study animals indicate that lipophilic pesticides tend to have lower MRLs than hydrophilic pesticides, primarily due to the relatively high toxicity and biotransfer factors of lipophilic pesticides. In addition, we observe that, primarily for lipophilic pesticides, upstream and downstream regulations are not aligned in terms of defining MRLs in feed using current MRLs in crops with relevance to feed and foods of animal origin.

CONCLUSION

Some of the current pesticide regulations in the livestock-product supply chain need to be re-evaluated to ensure that MRLs in the upstream sector (i.e., crops) do not result in unacceptable residues in the downstream sector (i.e., MRLs in livestock products affecting animal and human health). Finally, we provide recommendations for optimizing the derivation of MRLs in feed, including the evaluation of residue fate during feed and food manufacturing processes. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.