Chicken is a high-quality protein source consumed globally, and as the global population grows, broiler chicken production will increase. A meta-analysis of 57 broiler chicken production life cycle assessments (LCA) (173 individual assessments) was conducted to compare environmental impact results by production type and across regions. Findings indicate no significant differences in global warming potential (GWP) between conventional and organic/free-range systems. However, acidification and eutrophication were significantly higher in the organic/free-range system compared to the conventional system. These results challenge the assumption that organic production is the least environmentally impactful system, at least according to standardized LCA impact metrics. Geographically, North and South American broiler chicken production had lower GWP than European broiler chicken production, and all outperformed Asian broiler chicken production. No studies examined broiler chicken production in mainland Africa. Additionally, inconsistent reporting of functional units and impact categories complicated comparisons. This study highlights sustainable agriculture’s complexities and the need for a holistic approach to food systems.
Risner et al. (Wed,) studied this question.