PFAS (poly- and perfluorinated alkyl substances) is a generic term for a large group of substances. Anyone who ingests PFAS over a long period of time, for example in drinking water, risks ingesting more PFAS than is considered safe.
PFAS enter the body via sources other than drinking water, such as certain types of freshwater fish, and over long periods of timeperiods, these substances accumulate in the body. Therefore, measures should be taken to ensure that the concentrations of PFAS in drinking water are as low as possible.
In 2020, the European Food Safety Authority (Efsa) established its assessment of how much PFAS can be ingested without posing a risk to health. The new established health-based guideance value is 4.4 nanograms per kilogram of body weight per week (TWI) and applies to the combined amount of four different PFAS substances. This is a sharp reduction compared to the previous guidelines for tolerable intake for PFOS and PFOA, established in 2008.
If a water source is, or is suspected to be, affected by PFAS, the concentrations in the drinking water should be investigated.
Examine drinking water for the PFAS listed in the table below.
Carry out these examinations continuously over time and under different conditions. This approach will help to map the size, composition, seasonal variations and trends of any contamination. The composition of different PFAS can provide information on the origin of the contamination.
Areas not initially suspected to be affected may also need to be investigated at a later stage. This depends on the properties and mobility of the substances in the soil. Assess any findings of PFAS in drinking water against the action levels set out below.
Appropriate PFAS to examine in drinking water:
|1||Perfluorobutane sulfonic acid (PFBS)|
|2||Perfluorohexane sulfonic acid (PFHxS)|
|3||Perfluorooctane sulfonic acid (PFOS)|
|4||Fluorotelomer sulfonic acid (6:2 FTS)|
|5||Perfluorobutanoic acid (PFBA)|
|6||Perfluoropentanoic acid (PFPeA)|
|7||Perfluorohexanoic acid (PFHxA)|
|8||Perfluoroheptanoic acid (PFHpA)|
|9||Perfluorooctanoic acid (PFOA)|
|10||Perfluorononanoic acid (PFNA)|
|11||Perfluorodecanoic acid (PFDA)|
Action levels for drinking water
There are currently no legally binding limit values for PFAS in drinking water, but drinking water must not contain substances at such concentrations that they may pose a risk to human health (Paragraph 7 of the Swedish Food Agency’s Drinking Water Ordinance, SLVFS 2001:30)
The Swedish Food Agency has therefore developed an action level for PFAS of 90 nanograms/litre and recommends that drinking water producers consider it until legally binding limit values are in place.
In case of the discovery of high concentrations of PFAS, please contact the Swedish Food Agency for individual discussions on risk management. This also applies to PFAS substances that are not covered by the Swedish Food Agency’s action level.
If the drinking water contains PFAS above 90 nanograms/litre
Take immediate action to reduce the PFAS concentration in the drinking water to as far below the action level as possible.
If the drinking water comes from a surface water source, examine the PFAS content of the raw water. Inform the local health authority if the PFAS concentration in the raw water exceeds the action level for drinking water. This is justified because it might require additional risk management for the consumption of fish (see below under the heading “Recommendation — the risk management of PFOS in self-caught fish”.
Contact Swedish Water and Wastewater Association for further information on measures to reduce the concentration of PFAS in the waterworks.
If the drinking water contains PFAS above 900 nanograms/litre
Avoid drinking the water or preparing food with the water until the concentration is reduced as low as possible below 90 ng/litre.
Contact the Swedish Food Agency for further recommendations on risk management measures.
Calculation and assessment of the PFAS content
Calculate the total PFAS content of the drinking water in each sample as the sum of all findings of PFAS in the table above. Results that are “less than” (<) should not be included in the summation.
The limit of quantification (LOQ) for individual PFAS should be as low as possible. There are laboratories that offer analyses with quantification limits below 1 nanogram/litre.
Compare the total measured PFAS concentration with the action level of 90 nanograms/litre.
In December 2020, the EU decided on PFAS limit values in a new drinking water directive. These values are binding for all countries within the EU. See below under the heading “New limit values for PFAS in drinking water”.
The Swedish Food Agency has developed temporary recommendations for self-caught fish pending the risk and benefit assessment of fish commissioned from the Efsa by the European Commission.
he Efsa assessment weighs the benefits of eating fish against the risk of exposure to various environmental pollutants, including PFAS substances. This work is estimated to take 2-4 years.
In fish from places contaminated by PFAS, the levels may be elevated. In the case of fish that is consumed, the risk management recommendations are limited to perfluorooctanesulfonate (PFOS), as this is the PFAS that occurs in the highest concentrations in fish.
The fish at risk of having the highest concentrations of PFOS are fish caught in watercourses located in areas with confirmed PFAS contamination. That is why the work of environmental authorities in identifying contaminated sites is very important.
The Swedish Food Agency considers that the consumption of fish with concentrations that exceed TWI over short periods of timeperiods does not pose an increased risk to health. However, whenever possible it is important to restrict, or refrain from, regularly eating fish known to contain high concentrations of PFAS.
Recommendations - self-caught fish
If PFAS contamination of surface water is suspected, PFOS content of fish consumed by humans, such as perch, from lakes should be investigated.
As a temporary action level for fish, the Swedish Food Agency recommends the environmental quality standard for fish. It is set at 9.1 ng/g for PFOS in fish. The environmental quality standard is a measure of whether the fishing location can be considered affected in addition to background locations/concentrations.
If the levels of fish consumed by humans are above the environmental quality standard of 9.1 ng PFOS/g, the fish species caught from the lake and regularly eaten should be examined. The cause of the elevated concentrations should also be investigated.
Recreational fishermen who eat a great deal of self-caught fish should find out the local conditions regarding environmental toxins in the watercourses where they usually fish. This information can be obtained from the relevant municipality or county administrative board.
Municipalities and county administrative boards are encouraged to contact the Swedish Food Agency for support with handling cases of high levels of PFOS in fish.
In December 2020, the EU decided to incorporate PFAS limit values in a new drinking water directive. These values are binding for all countries within the EU. The directive will be implemented into the national drinking water regulations no later than 12 January 12th 2023.
The EU Drinking Water Directive is a so-called minimum directive. This means that member states may choose to introduce stricter legislation into their national regulations.
The goal of the Swedish Food Agency is to introduce a national limit value for PFAS in drinking water when the Drinking Water Directive is implemented into the national drinking water regulations. The limit value should be adapted according to the conditions in Swedish drinking water. As far as possible, it should also take into account the EFSA health-based guidance value from 2020.
The European Commission’s limit values for PFAS in drinking water:
PFAS 20: 100 ng/l
PFAS total: 500 ng/l
For PFAS 20, these congeners are highlighted:
|1||Perfluorobutanoic acid (PFBA)|
|2||Perfluoropentanoic acid (PFPA)|
|3||Perfluorohexanoic acid (PFHxA)|
|4||Perfluoroheptanoic acid (PFHpA)|
|5||Perfluorooctanoic acid (PFOA)|
|6||Perfluorononanoic acid (PFNA)|
|7||Perfluorodecanoic acid (PFDA)|
|8||Perfluoroundecanoic acid (PFUnDA)|
|9||Perfluorododecanoic acid (PFDoDA)|
|10||Perfluorotridecanoic acid (PFTrDA)|
|11||Perfluorobutane sulfonic acid (PFBS)|
|12||Perfluoropentane sulfonic acid (PFPS)|
|13||Perfluorohexane sulfonic acid (PFHxS)|
|14||Perfluoroheptane sulfonic acid (PFHpS)|
|15||Perfluorooctane sulfonic acid (PFOS)|
|16||Perfluorononane sulfonic acid (PFNS)|
|17||Perfluorodecane sulfonic acid (PFDS)|
|18||Perfluoroundecane sulfonic acid (PFUnDS)|
|19||Perfluorododecane sulfonic acid (PFDoDS)|
|20||Perfluorotridecane sulfonic acid (PFTrDS)|