As thousands of pigs eat and breath and defecate in the concentrated confines of a modern-day hog barn, CO2 levels can skyrocket – up to 5,000 parts-per-million, more than 12 times the normal atmospheric concentration.

That was seen chiefly as a climate problem, something for the future.

New research points to a far more immediate impact, particularly for the workers tending to those animals: elevated carbon dioxide in confined pig farms may worsen dust-induced lung problems in farmworkers.

Researchers from the University of Nebraska Medical Center exposed mice to dust taken from hog farm barns and housed them in boxes with several different CO2 levels. The higher the exposure to CO2, the more inflammation the mice experienced.

The study suggests industrial hog farms should take carbon dioxide into account when examining ventilation and workers’ safety equipment.