Per- and polyfluoroalkyl substances (PFAS) are a class of synthetic organic chemicals that contain fluorine. There are more than 3,000 PFAS. Because many PFAS have useful properties, some of them have been used since the 1940s in products like textiles, paper, cookware, firefighting foams, and electronics. Though U.S. production of some of these chemicals has declined, many are still produced in other countries. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) have been among the most used PFAS. U.S. EPA is currently considering the addition of PFAS chemicals to the Toxics Release Inventory, as well as rules to regulate exposures of certain PFAS chemicals.
PFAS in the Environment
PFAS are commonly present at fire training and response sites, certain industrial facilities, landfills, wastewater treatment plants, and in biosolids. PFAS persist in the environment, can bioaccumulate, and are often present in people and in wildlife. Due to the large volumes of PFOS and PFOA used in the past, those chemicals are the most frequently detected PFAS.
PFAS Health Effects
Studies on animals suggest that some PFAS may be toxic. Research has not determined at what level these substances may be dangerous to humans. Research on the possible health effects of PFAS continues.
Looking for PFAS
U.S. EPA has developed analytical methods for selected PFAS in drinking water, surface water, groundwater or waste water. Sampling and analysis methods for PFAS in other parts of the environment are under development. U.S. EPA proposed nationwide drinking water monitoring for PFAS at smaller public water systems beginning in 2022. No verified PFAS detections were found in Indiana public water systems tested during the previous sampling period.
Development of Standards
At this time, the U.S. EPA has only established a 70 ng/L (nanogram per liter, or parts per trillion [ppt]) Lifetime Health Advisory (LHA) for PFOA and PFOS in drinking water. This LHA is applicable to PFOA and PFOS individually, or in combination, if both chemicals are present at concentrations above the reporting limit in drinking water. The LHA is not a legally enforceable federal standard and is only advisory in nature; it is subject to change as new information becomes available. EPA is developing a legally enforceable standard, but is not moving quickly. That is why several states, including neighboring states of Michigan and Wisconsin, are developing their own set of standards.
Currently available remedies for PFAS in water include filtration and chemical treatment. Excavation and disposal, physical barriers, and heat treatment are among effective remedies for PFAS in soils. Other technologies are under development by the U.S. EPA, the U.S. Department of Defense, private industry, academic research institutions, and others.
- Development of Screening Levels
- At this time, IDEM has published screening levels for three PFAS compounds listed in Table A-6 of the Remediation Closure Guide. Screening levels are concentration levels specific to individual chemicals, land uses, and media (soil, water, indoor air) that IDEM has determined to be protective of human health. IDEM’s current policy calls for publication of PFAS screening levels following U.S. EPA publication of the same. In 2019, the U.S. EPA provided recommendations on interim cleanup recommendations to address groundwater contaminated with PFOA and/or PFOS and sought public comment on these recommendations in the summer of 2019; they are moving forward with the development of enforceable levels for PFOA and PFOS.
- Partnering with Stakeholders
- Since fire fighting foam is known to contain these contaminants, military bases have been a concern. That is why the military is sampling at military locations around the state. Results have not been concerning. IDEM will also be partnering with the Ohio River Sanitation Commission (ORSANCO), which will sample the Ohio River to determine background levels of these contaminants in the river.
- Acronyms List
- Enforcement Database
- Impaired Waters (e303d)
- Online Air Permit Search
- Online Payment Options
- Real-Time Monitoring
- Regulatory Services Portal
- Safe Drinking Water Information Search
- Search for Authorization Status
- Virtual File Cabinet
- Wastewater Certification Renewal
- More IN.gov Online Services
- IN.gov Subscriber Center