Submitted to: Water Environment Federation
Publication Type: Proceedings
Publication Acceptance Date: 4/19/2000
Publication Date: N/A
Technical Abstract: Quantification of odor and trace gases from animal production facilities has traditionally been addressed in separate, unrelated research efforts due to analytical difficulties associated with the measurement of low concentrations of analytes in air samples. This lack of information has impeded research efforts focused on the development of emission abatement strategies and has necessitated the use of subjective, low-throughput odor measurement methods. In this study, direct measurements of malodorous volatile organic compounds (VOCs) present in ambient air samples from 29 swine production facilities were used to develop a 19 component VOC odorant standard that was observed to mimic olfactory properties of swine manure. The emission profile for the standard VOC solution was optimized in a laboratory dynamic emission chamber to simulate VOC emission profiles of swine effluent. Analyses employing either a human panel consisting of 14 subjects or gas chromatography were performed on the air stream from the emission chamber to assess human olfactory responses or odorant concentration, respectively. Panelists were asked to compare odor intensity of each of the six air samples to a VOC reference standard of defined magnitude. A statistically significant synergistic olfactory response was observed to occur when the air concentration of acetic acid or 3-methyl indole (skatole) was increased relative to the concentration of other VOC odorants in the standard. The collective odorant responses for swine waste VOC were utilized to develop a prediction model to estimate human odor response magnitudes through measured air concentrations of "indicator" VOC odorants.