PFASs in groundwater – a risk for swedish drinking water

1. PFASs in groundwater – a risk for Swedish
drinking water?
Stefan Banzhaf 1, Jeffrey Lewis 2, Charlotte Sparrenbom 3, Roland Barthel 1
1 Department of Earth Sciences, University of Gothenburg, Göteborg, stefan.banzhaf@gu.se
2 Tyréns AB, Umeå
3 Department of Geology, Lund University, Lund
Grundvattendagarna 13-14 oktober 2015, Göteborg
– Session Föroreningar –

2. Gone viral…?
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3. What are PFASs?
PFASs = perfluoroalkyl and polyfluoroalkyl substances
- Multiple industrial uses, e.g. as water repellent surfaces on
clothing, leather, paper and as firefighting foam
- Produced since the 1950s
- Very diverse group with different properties, mainly depending
on their chain length
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4. Transport behavior in (ground-)water
- PFASs are insoluble in the form used for industrial applications
and in end consumer products
- They form ions in the aquatic environment, which are then highly
water soluble
- Chain length influences mobility: short-chained PFASs are more
mobile in groundwater than long-chained ones
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5. “Prominent” PFASs compounds
PFOS C8HF17O3S
- Major applications: firefighting foams, fabric protector
- Banned in the EU 2006
- PFOS-containing firefighting foam banned from sale 2008,
usage no longer allowed since 2011
- Listed in the Stockholm Convention (Annex B, restriction) since
2009: “Restriction of production and use, in accordance with the
provisions of that annex.”
- Listed in EU Water Directive as priority substance since 2013
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6. “Prominent” PFASs compounds
PFOA C8HF15O2
- Major applications: carpets, firefighting foam, production of
PTFE (“Teflon”) and water repellant clothing (e.g. “Gore-Tex”)
- EU will submit proposal to add PFOA to the Stockholm
Convention (Annex A, elimination): “Elimination of production
and use of all intentionally produced persistent organic
pollutants.”
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7. A problem for the aquatic environment…
- Highly mobile in the aquatic environment, persistent and
bioaccumulative
- Found worldwide in the aquatic environment and wildlife
- Toxicity is known for some PFASs, e.g. PFOS
- More PFASs are suspected to be toxic to mammals, not
thoroughly studied yet
= Anthropogenic environmental pollutants!
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8. How do PFASs enter groundwater?
Point sources
- Firefighting training areas
- Wastewater treatment plants
- Landfills
Diffuse sources
- Application of biosolids from wastewater treatment plants to
agricultural fields
- Bank filtration
- Managed aquifer recharge
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9. PFASs in drinking water
How do they get there?
- Via contaminated surface water, e.g. at bank filtration sites
- Via contaminated groundwater
- Low elimination during drinking water treatment
Why problematic:
- PFASs-contaminated food and drinking water are assumed to
contribute significantly to PFASs uptake of humans
- Both public water works and private wells are affected
- Especially in private wells there is no regular control of drinking
water quality 9

10. PFASs in Swedish groundwater – why bother?
- PFASs are detected in Swedish groundwater
- 50 % of Sweden’s drinking water comes from groundwater
- Exposure via contaminated drinking water is linked to increasing
PFASs concentrations in blood serum, e.g. in Uppsala
- Once contaminated, an aquifer will form a long lasting problem
due to the persistence of PFASs
- Adverse health effects for humans as a consequence of long
time exposure not finally clarified but highly suspected!
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11. The current situation in Sweden
- First environmental screenings already 10 years ago – did not receive
much public attention
- Detections of PFASs countrywide, both at public water works and in
private wells
- Concentration on firefighting training areas as sources for PFASs
- According to Livsmedelsverket 3.4 million people in Sweden are
exposed to PFASs contaminated drinking water
- Some groundwater based waterworks already had to cease
operation, e.g. Kallinge, Botkyrka
- No threshold value for PFASs in groundwater or surface water
- No guidelines on sampling frequency for PFASs at water works
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12. The current situation in Sweden
- First environmental screenings already 10 years ago – did not receive
much public attention
- Detections of PFASs countrywide, both at public water works and in
private wells
- Concentration on firefighting training areas as sources for PFASs
- According to Livsmedelsverket 3.4 million people in Sweden are
exposed to PFASs contaminated drinking water
- Some groundwater based waterworks already had to cease
operation, e.g. Kallinge, Botkyrka
- No threshold value for PFASs in groundwater or surface water
- No guidelines on sampling frequency for PFASs at water works
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13. Until then: PFASs7 according to Livsmedelsverket
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Name, Livsmedelsverket Abbreviation Name, English
Perfluorbutansulfonat PFBS Perfluorobutanesulfonic acid
Perfluorhexansulfonat PFHxS Perfluorohexanesulfonic acid
Perfluoroktansulfonat PFOS Perfluorooctanesulfonic acid
Perfluorpentanoat PFPeA Perfluoropentanoic acid
Perfluorhexanoat PFHxA Perfluorohexanoic acid
Perfluorheptanoat PFHpA Perfluoroheptanoic acid
Perfluoroktanoat PFOA Perfluorooctanoic acid

14. What if PFASs7 are detected in drinking water?
PFASs7 present but <90 ng/l  “found”
- Try to minimize PFASs exposition via drinking water
PFASs7 >90 ng/l  “limit of action”
- Take action asap to reduce PFASs below limit of action
- Analyze PFASs in raw water if drinking water comes from surface water,
if also above limit of action inform the local control authority
PFASs7 >900 ng/l  “health based guideline”
- Women trying to become pregnant, are pregnant or breastfeed should
avoid drinking the water
- Livsmedelsverket has to be contacted for individual risk assessment
Summarized from Livsmedelsverkets recommendation “Riskhantering - PFAA i dricksvatten”
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15. PFASs7 in Swedish water bodies
Type Number of water bodies Detection frequency [%]*
Surface water 27 37
Artificial recharge 12 50
Groundwater 193 19
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*Detection limit for individual species: 1 or 2.5 ng/l
Holmström, K., Wetterstrand, S., Hedenberg, G., 2014. Nationell screening av perfluorerade föroreningar (PFAA) i
dricksvatten. Svenskt Vatten Utveckling. Rapport Nr 2014–20.
- Svenskt Vatten survey 2014, raw and drinking water
- Dataset represents water production for 4.3 million end consumers
in 112 communities
- In total 22 % of all samples (52 out of 236) contained PFASs in
detectable amounts
- PFOS and PFOA were the species most frequently detected

16. What is awaiting us in the future?
Ongoing new contamination with PFASs as also banned PFASs
compounds (e.g. PFOS) are simply replaced by other PFASs that
might be as toxic as the ones replaced
Remaining contamination due to the persistence of PFASs in the
aquatic environment
Contamination due to derivatives of PFASs compounds and even
new formation of banned compounds like PFOS that form without
further release into the environment
 PFASs are a long term problem for drinking water supply! It
will maybe get even worse in the future! 16

17. PFASs in groundwater – a risk for Swedish
drinking water?
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Unfortunately a clear ”Yes” is the answer!
PFASs in groundwater have to be considered as
”trouble contaminants of the future”

18. Tack! Frågor?
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