A Survey of the concentration of ammonia recorded in pig housing in England

Abstract

In animal housing ammonia is an aerial pollutant resulting from the microbial conversion of nitrogenous materials excreted in faeces and urine. Ammonia is an irritant to cells lining the respiratory tract and an increased incidence of pneumonia in pigs and humans and atrophic rhinitis in pigs have been correlated with elevated ammonia levels. In a survey of 12 farms and 49 pig buildings concentration of ammonia was identified specifically as a causative agent in the aetiology of atrophic rhinitis (Robertson, Wilson and Smith 1990). Furthermore, high levels of ammonia can delay the onset of puberty in gilts perhaps as a result of the masking of boar odour (Malayer, Brandt, Green, Kelly, Sutton and Diekman 1988).Regulations have been introduced (Control of Substances Hazardous to Health (COSHH)) limiting the exposure of humans to atmospheric ammonia to a mean level of 25 ppm over an 8h work shift and 35 ppm for 10 minute exposure. As part of a study on the effectiveness of a feed additive formulated to control atmospheric ammonia, levels of ammonia in pig housing were monitored.