Preventing PFAS Contamination from Landfills will Protect Human and Environmental Health

Per- and poly-fluoroalkyl substances (PFAS) are a broad group of man-made chemicals that are used to manufacture a wide range of everyday products such as non-stick cookware, food packaging, stain-resistant fabrics used to produce carpets, upholstery, garments, as well as in fire-fighting foam and other industrial applications. Major sources of environmental PFAS contamination include fire fighting activities (firefighter training and responding to fires), industrial manufacturing plants, landfills and wastewater treatment facilities.

Health Risks Associated with PFAS Contamination of the Environment

Once PFAS gets into the environment, it can contaminate soils and water. Because PFAS doesn't break down readily, but rather persists in the environment, it can bioaccumulate in the bodies of organisms and therefore poses a significant health risk to organisms at the top of the food chain (including humans).

Since PFAS chemicals are so widely used in consumer and industrial products, exacerbated by their persistent nature and mobility, they pose a significant environmental health risk, particularly in drinking water.

Existing Safety Measures May be Ineffective at Preventing PFAS Contamination

Many PFAS-containing consumer products eventually end up in landfills. Modern municipal solid waste landfills have liners and leachate collection systems installed to prevent environmental contamination by landfill leachate and landfill gas emissions. However, the persistent nature of PFAS, means that it is less likely to break down readily on a landfill compared to other forms of waste. The long-lived nature of PFAS exacerbates the potential dangers of PFAS chemicals in waste.

increases the risk that it could leach from waste over time, and escape to the environment via leachate or landfill gas emissions. Studies (1,2,3) have found PFAS contamination in landfill leachate in the US.

Various factors can contribute to PFAS contamination of the environment from landfills. These include the types of waste the landfill receives, the design of the waste management system (for example, the type of liner or leachate collection system used, if any) and the condition of the various components, as well as the leachate management procedures that are employed.

The leachate collected from a landfill site typically gets sent to a wastewater treatment facility for treatment before being discharged into the environment. However, some landfills pre-treat the leachate before discharging it. Wastewater treatment facilities may reject landfill leachate or industrial wastewater with high levels of PFAS, as conventional methods used to treat wastewater are typically ineffective at reducing PFAS, resulting in PFAS being discharged into freshwater systems where it can contaminate drinking water and pose an ecological and human health risk.

The EPA acknowledges that the fate and transport of PFAS in landfills is complex and requires further research in order to gain a clearer understanding of these processes.

According to the EPA, these studies should focus on assessing the types, concentrations and occurrence of PFAS in landfill leachates, wastewaters, and other wastes across the U.S., as well as improved methods for controlling release and treatment. Furthermore, similar treatment technologies (physio-chemical or biological treatments) for leachate are also used for groundwater and drinking water (4, 5). For example, biologically-active coated sand grains are used in biofiltration of wastewater and drinking water. In-situ groundwater bioremediation involves injection of biological active agents that may also coat sand grains, if present. Therefore, leachate treatment methods that may also be applicable for treating groundwater and drinking water for effectively removing PFAS are desirable.

Journal References

1. Hamid, H., Li-a, L., Grace, J., Review of the fate and transformation of per- and polyfluoroalkyl substances (PFASs) in landfills. Environmental Pollution. 235:74-84. (2018).
2. Allred, B.M., Lang, J.R., Barlaz, M.A., Field, J.A., Orthogonal zirconium diol/C18 liquid chromatography tandem mass spectrometry analysis of poly and per-fluoroalkyl substances in landfi ll leachate. J. Chromatogr. A 1359: 202-211. (2014).
3. Huset, C.A., Barlaz, M.A., Barofsky, D.F., Field, J.A., Quantitative determination of fluorochemicals in municipal landfill leachates. Chemosphere 82: 1380-1386. (2011).
4. Merino, N., Qu, Y., Deeb, R.A., Hawley, E.L., Hoffmann, M.R., Mahendra, S., Degradation and removal methods for perfluoroalkyl and polyfluoroalkyl substances in water. Environ. Eng. Sci. 33 (9): 615-649. (2016).
5. Rahman, M.F., Peldszus, S., Anderson, W.B., Behaviour and fate of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in drinking water treatment: a review. Water Res. 50: 318-340. (2014).

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