By Michelle Onofrio, National PFAS Technical Manager, ALS USA Environmental

Per- and polyfluoroalkyl substances (PFAS) are hazardous compounds that have been used heavily in manufacturing since the 1950s. While their usefulness is derived from their chemical structure, the strong carbon-fluorine (C-F) bonds present in these compounds render them resistant to degradation. PFAS are well-known to be persistent and ubiquitous in the environment and have been found in environmental samples around the globe, but the distribution and concentrations of these contaminants vary across the USA.

The wide array of brownfield redevelopment sites presents a multitude of potential contamination sources. When considering the potential for high levels of PFAS contamination, it is important to consider the history of land use at a particular site and the site’s proximity to certain areas. In this article, we discuss how to consider historical land use to anticipate whether PFAS are likely to be contaminants of concern.

Manufacturing and chemical sites

Obvious sources of PFAS contamination include manufacturing facilities that developed PFAS or used PFAS heavily in manufacturing processes. Industrial use of PFAS is highly concentrated in the Northeastern USA, especially along the I-95 corridor.

Regions with historical manufacturing of chemicals, paints and coatings, urethane and foam, textiles and carpeting, paper and food packaging, plastics and resins, metal plating, and other industrial processes are likely to contain high levels of PFAS in the surrounding environment.

Manufacturing processes that typically do not involve PFAS are less likely to have PFAS contamination as a major concern. These include bricks and ceramics manufacturing, lumber milling and woodworking, blacksmithing and metal forging, and glassmaking.

The age of a manufacturing facility can also be an indicator of whether PFAS contamination is present; areas that were only used for manufacturing before the 1950s are unlikely to pose a risk for PFAS contamination.

Airports and firefighting training areas

Aqueous film-forming foam (AFFF) is used to combat specific fires, including aviation fires. AFFF typically contains very high concentrations of PFAS, so airports and firefighting training locations may be source locations for significant PFAS contamination. Until recently, AFFF was typically not treated as hazardous waste after use.

Instead, it was generally washed away with water, introducing high concentrations of PFAS to soil, groundwater or surface water in the surrounding environment. AFFF storage tanks and systems may still contain PFAS, even if the systems are no longer in use.

Municipal and industrial waste landfills

Before health risks associated with PFAS were known, PFAS were used in many common household items including nonstick cookware, food packaging materials, personal care products, cleaning products, electronics, and clothing and carpeting manufactured to be water-resistant, stain-resistant and/or fire-resistant.

Once discarded, these items introduce PFAS into municipal landfills. Landfills that have accepted industrial waste from PFAS-heavy manufacturing facilities are also likely to contain increased concentrations of PFAS.

Wastewater treatment plants and land-applied sewage sludge and biosolids

Sewage sludge refers to untreated residual material produced by wastewater treatment plants, while biosolids indicate a sludge that has received some level of treatment. Sewage sludge and biosolids have been used for land applications since the early 1900s. The standards for wastewater treatment established by the Clean Water Act in 1972 resulted in an increase in the generation of biosolids, and subsequently land application throughout the country.

Sewage sludge treatment does not specifically target PFAS, so even treated biosolids can contain these contaminants. Wastewater treatment plant discharge and land-applied biosolids, especially if produced near highly contaminated areas, are likely sources of PFAS contamination in the environment.

Analytical considerations for highly contaminated sites

Samples originating from the areas described may contain PFAS at concentrations of orders of magnitude higher than other typical samples. When considering a laboratory partner for analysis of these types of samples, it is beneficial to ensure the laboratory employs mitigation strategies to overcome the challenges of processing high-concentration PFAS samples.

Communication throughout the course of your site testing and analysis project is crucial; it is encouraged to discuss site history with your project manager, and you should expect timely updates regarding any challenges that may arise.

High-quality data and rapid turnaround times are achievable with these types of projects, especially when using a laboratory experienced in analyzing highly contaminated samples for PFAS.

The Author:

Michelle Onofrio is the National PFAS Technical Manager for ALS USA Environmental. Michelle provides technical support on workflow optimization and new method development, prioritizing quality and consistent, reliable service. Michelle works closely with the company's PFAS laboratories throughout the country in New York, New Jersey, Pennsylvania, Michigan, Texas, and Washington.