Air Pollutants around an Animal Feed Processing Facility in Nacogdoches, TX: A Study on Their Effect on Local Outdoor Air Quality

Stephen F Austin State University, Baker Pattillo Student Center, Student Center Theatre and Twilight Ballroom

In this exploratory study, different odorous compounds were measured near TFP Nutrition to better understand the impact of odor on local outdoor air quality. TFP Nutrition produces pet feed, livestock feed, and agricultural fertilizer for local brand Lone Star Feeds. It is known in the Nacogdoches area for producing powerful odors near its facilities. It is in the downtown area of the city and in proximity to an elementary school, recreational softball fields, and residential homes. Odors can be connected to the presence of air pollutants. This study on air quality was performed to quantify this data on odors for public education, health purposes, and further research if necessary. Two Nasal Ranger® Field Olfactometers (St. Croix Sensory) were used simultaneously: one evaluated general odor while the other evaluated ammonia (NH ₃ ) odors. In addition, weather conditions, which included temperature, wind direction, and wind speed, were collected using two pocket weather trackers (Model 4500, Kestrel). Sampling occurred twice per week at five different locations near the plant. Notable findings included dilution to threshold (D/T) ratios at the highest possible value of 60 at certain locations on different days. Overall, the highest D/T ratios for both categories of odors (general and ammonia) were found at location 4 southwest of the facility. Wind direction seemed to make a large impact as the highest D/T ratios were detected at times the wind traveled in a direction from the facility toward the sample locations. An important discovery was that each time a D/T ratio greater than 2 was detected on the Nasal Ranger evaluating general odor, a D/T ratio of equal or lesser value was also detected on the Nasal Ranger evaluating ammonia odor, making the connection that much of the odor from this facility may be related to ammonia.