A recently published paper in the Journal of Cleaner Production details the carbon footprint of intensive egg production in Spain, finding 2.66 kgCO₂ equivalent per dozen eggs. The authors of the article “Environmental assessment of intensive egg production: A Spanish case study,” conclude that environmental improvement actions should be directed mainly towards optimizing hen feed formulations. This is a similar finding to a 2013 environmental assessment conducted assessing Midwestern United States.

A recent article published in Poultry World provides an excellent summary of the Spanish paper.