When sampling for PFAS, there are many special guidelines that need to be followed in order to avoid cross-contamination. These guidelines differ from sampling for other types of contaminants, due to the fact that PFAS are present in many things we use in our every day life. These chemicals have been widely used to produce products that are water resistant, stain resistant, heat resistant and/or oil resistant. Since PFAS are analyzed in such small quantities, called parts per trillion, even the smallest cross-contamination could contribute to producing a false positive.
To avoid the possibility of cross-contamination, it is important that the sampler take special precautions before even arriving at the sampling location. Some of the commonly known items that can contain PFAS are non-stick pans, water resistant shoes and clothing, fire-fighting foam, and stain resistant carpeting. It is easy to avoid these types of items when sampling for PFAS, as they are obvious potential sources, but there are many more potential sources of cross-contamination.
It has been documented that PFAS can be present in personal care products such as cosmetics and lotions, some insect repellants and sunscreens, and even in pizza boxes and fast food wrappers. Recycled paper products such as paper towel and notebook paper are also potential sources of cross-contamination, due to the possibility of containing PFAS-treated paper that was recycled. Sampling equipment may also contain PFAS, either in the material of the equipment itself or due to PFAS being used in the manufacturing process. Interior parts of equipment must be evaluated for PFAS content, such as the O-ring in faucets, in case the equipment comes into contact with the sample. Even the gloves that the sampler wears need to be considered – ordinary latex gloves cannot be used; they must use powderless nitrile gloves.
The sampler must always be aware of the way PFAS is integrated into many products and materials in our everyday lives and their potential for cross contamination when sampling. The overall General PFAS Sampling Guidance document should be reviewed before utilizing a media-specific guidance document.
|Technical Guidance Documents||Residential Guidance Documents|
General PFAS Sampling Guidance (Revised 10/16/2018)
Groundwater PFAS Sampling Guidance (10/2018)
Residential Well PFAS Sampling Guidance (Revised 10/11/2018)
Soil PFAS Sampling Guidance (11/28/2018)
Surface Water PFAS Sampling Guidance (11/28/2018)
Wastewater PFAS Sampling Guidance (Revised 10/11/2018)
PFAS Sampling Quick Reference Field Guide (Revised 10/17/2018)
Sampling and Lab Information (10//2018)
MDEQ PFAS Minimum Laboratory Analyte List
This is the minimum laboratory PFAS analyte list for analysis of deer, drinking water, groundwater, surface water, soil, wastewater effluent, and landfill leachate samples collected by Michigan’s Departments of Environmental Quality, Health and Human Services, Agriculture and Rural Development, and Natural Resources.
This minimum analyte list was developed based on the potential for these chemicals to be found in Michigan, the availability of the chemical standards used for testing, and the ability of available laboratories to test for these PFAS analytes. This list includes PFAS that can be tested for in drinking water using United States Environmental Protection Agency (USEPA) Method 537 Rev. 1.1, which is the only method that should be used when analyzing drinking water samples. Other testing methodology may be used to test for PFAS in other media (not drinking water). This list is not exhaustive of PFAS in Michigan’s environment.