Organic eggs have worse climate impact than caged chicken eggs, study finds

Researchers attribute this disparity to the lower efficiency of organic free-range models, which require more chickens to produce the same number of eggs. Furthermore, organic free-range production was found to have the highest potential for water eutrophication, acidification, and land use, alongside the highest chicken mortality rates.

However, the study's authors acknowledge limitations, including the use of data from 2009-2010, which may not reflect recent advancements in egg production. The research also did not account for other environmental factors such as pesticide use or biodiversity impacts.

Dr. Harriet Bartlett, a senior research associate at Oxford University's Smith School of Enterprise and the Environment and one of the study's authors, highlighted that egg production's environmental impact often receives less attention than that of meat and dairy. She noted that farms generally considered better for animal welfare, like organic and free-range, can have higher environmental costs due to lower efficiency.

Lee Holdstock, head of regulatory and trade affairs at Soil Association Certification, who was not involved in the study, commented that while intensive systems may have lower emissions per unit of output due to feed efficiency, this represents only one aspect of environmental impact. He emphasized that a sustainable food system must also consider nature, soil health, water quality, synthetic inputs, and animal welfare.