Swine production impact on residential ambient air quality.

Numerous residents in agricultural areas are concerned about the impact that the swine industry may have on the ambient air quality. They assume there is a risk because there is limited information on the airborne contaminant that may originate from these facilities. The objective of the project was to assess the impact of swine production on ambient air quality related to public health in farming communities. Of the six chosen communities, three were considered not to be in a swine production area, whereas the three others were considered to be within a swine production area. Data were collected during three periods in spring and summer 2006. Ammonia and hydrogen sulfide concentrations were monitored on a continuous basis whereas odor concentrations and intensities were monitored twice a week. Odor concentrations were measured by dynamic olfactometry and odor intensities were determined by trained odor assessors. Public health was evaluated by survey questionnaires sent to a sample of residents in each of the six communities. Average NH(3) concentrations ranged from 6.9 to 12.6 ppb for nonexposed communities and from 8.9 to 18.3 ppb for exposed communities. Average H(2)S concentrations ranged from 1.1 to 1.5 ppb for nonexposed communities and from 1.1 to 1.6 ppb for exposed communities. For a community in a swine production area, ambient NH(3) and H(2)S concentrations were found to be higher than those communities not in a swine production area; however, that difference was not significant and they were within air quality standards for public health and safety. Odor concentrations showed no significant difference between the nonexposed and exposed communities and between evening and morning periods. Odor intensities were found to be significantly higher in the communities within swine production areas. More research will be required to fully understand the correlation between specific physical symptoms from residents and the presence of odors from swine production.