Statement Regarding the Report on the Personal and Area Sampling of Air Contaminates at the Fairfield WPCF
On December 2, 2022, air sampling was conducted by HRP Associates to determine if there was any health risk from the increased odors related to the structural failure issue the WPCF is currently experiencing. The HRP Report details the numerous samples collected including personal sampling worn by staff, indoor air monitoring inside workspaces, outside air monitoring on the grounds and around the perimeter of facility as well as at composted biosolids storage area.
The results of the sampling showed no exceedances of any regulatory or industry standards for occupational exposure, ambient air or ambient air emissions. Even though there were no exceedances, the WPCF staff will continue to attempt solutions to address the current odor issue.
The sampling did indicate that, at two interior locations that handle sewage sludge, there where detectable amounts of Nitrosodimethylamine (NDMA), a carcinogen, which was found in the air at levels slightly over the detectable levels. According to the CDC Webpage on NDMA and the Agency for Toxic Substances and Disease Registry (ATSDR) Toxilogical Profile for NDMA, most people are exposed to NDMA, as it is formed through reactions internally within our own bodies from foods containing nitrite as well as with drinking water. Other exposures to NDMA also occur, as it can be present in foods, water, beer, cigarette smoke and to a lesser extent rubber products, toiletry and cosmetic products and pesticides. In addition, ATSDR does indicate that NDMA commonly occurs at low levels in wastewater treatment plants, since it can be present in low levels in drinking water and other substances in wastewater.
The Health Department consulted with subject matter experts from the CT Department of Public Health regarding the NDMA findings and was advised that an individual breathing the air at the highest NDMA concentration measured in indoor air at the WPCF would have an exposure that is well below the typical daily background exposure people have to NDMA. In addition, if you were to consider the dilution that would occur from the inside areas of the WPCF where NDMA was found in the air to the property line, residents in the area would have a significantly lower exposure, if any.
The HRP report makes a series of recommendations to investigate the potential sources of the NDMA and conduct sampling of materials to determine if any additional protections for WPCF workers need to be in place. The Town has initiated that investigation and has arranged for the recommended sampling to be completed this week.