Step 2: Are There PFAS Compounds Already in My Garden?

Because they are so common, most soil in Maine likely has at least a background level of PFAS (0.5 – 1 parts per billion). However, levels of contamination vary greatly based on the history of what has been applied to the soil. The highest levels tend to be associated with land that had sewage sludge from industrial sources applied. PFAS has also been found in some well water and surface water.  If this water was used for irrigation, PFAS may build up in the soil over time. Lastly, PFAS may be brought in through topsoil or soil amendments. More information on PFAS and where they came from: Step 1: What are PFAS and Where Did They Come From?

Steps to investigate the potential for PFAS impacts on your garden:

  • Start by learning about the history of your garden.
    1. Is the garden on old farmland that was treated with sewage sludge known to contain PFAS? The Guide to Investigating PFAS Risk on Your Farm (Steps to Determine PFAS Risk Specific to Your Farm) provides more information on determining the land application history of your land.
    2. Has manure been applied from a farm known to have PFAS contamination?
    3. Has material (compost, topsoil) been applied that contained sewage sludge? If so, was it tested for PFAS?
    4. Has the garden been irrigated with water with elevated PFAS levels? PFAS could be found in irrigation from groundwater if your garden is located adjacent to a place with a history of sewage sludge use, firefighting foam use (often associated with airports and Department of Defense sites) and/or manufacturing facilities that utilized PFAS.

If none of the above circumstances apply, the PFAS levels in your garden are unlikely to be above background levels (trace levels of 0.5 – 1 parts per billion).

  • If your research indicates that your garden soil or irrigation water may have been impacted by PFAS, you may want to have your water and/or soil tested by an accredited laboratory. 
To direct questions to University of Maine Cooperative Extension, please email:

Proceed to Step 3: Can I Test My Water for PFAS? →