Some PFAS, such as PFOA and PFOS have been associated with adverse effects in animal and human studies at sufficient levels of exposure. This has led to the restricted use of some of these substances in a variety of global markets. For many PFAS compounds there is a lack of toxicological data and research is still ongoing to better understand the health effects associated with low levels of exposure over long periods of time.
Recognising the potential for longer term accumulation of some PFAS in the human body, the independent quality regulator for drinking water the Drinking Water Inspectorate (DWI) has set guidance levels for PFAS that provide a precautionary margin of safety in advance of further international research on PFAS toxicology.
Based on current knowledge, the Drinking Water Inspectorate states that the low levels of PFAS detected in some untreated water abstracted for public drinking water supplies have no acute or immediate impact on human health.