According to a questionnaire study undertaken earlier this year by investigators at Tufts University's Cummings School of Veterinary Medicine, it is estimated that 4.6 million Americans involved in the equine industry may be at risk of developing respiratory symptoms due to poor air quality in horse barns.

The study found that 50 per cent of individuals working in barns complained of coughing, wheezing, or other ailments in the last year, compared to just 15 per cent in the control group.

According to the study, increased exposure to barns yielded higher rates of self-reported respiratory symptoms,

The study was published in the journal Occupational Medicine and funded by the National Institutes of Health.

Click here to the read a sciencedaily.com article regarding the study.

(With files from sciencedaily.com)