PFAS in Sweden, a broad overview. ATV Vintermøde 2017 Fagsession 3, PFAS 8. marts 2017 Niklas Törneman, Sweco Environment

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1 PFAS in Sweden, a broad overview ATV Vintermøde 2017 Fagsession 3, PFAS 8. marts 2017 Niklas Törneman, Sweco Environment 1

2 Overall attention in Sweden Conclusions from a SEPA national assessment Sources in Sweden PFAS in water supplies in Sweden Site investigations 2

3 Number of articles in Swedish press From mostly unknown to highly debated issue in a few years 600 Fire fighting training areas in Stockholm. PFAS in major drinking water supply. One lake closed. Several airport FFTAs 3 lakes closed and 2 water supplies closed Kallinge. Thousand s of individuals exposed to high PFAS levels in tap drinking water. Originating at a FFTA. Common issue, more sites Most sites not investiga ted Key word: 3 PFAS PFOS PFOA Fire Figthing Foam

4 SEPA National Assessment PFAS are widespread in surface water Widespread but more connected to point sources in Ground Water PFAS levels in fish in the vicinity of point sources may cause dietary restrictions Fish eating predators may be affected Based on GW investigations so far, at least people have been exposed to PFAS concentrations above 90 nanograms per litre in water from public water supplies Exposure via private water supplies is unknown. At least consumers receive their water from private wells located within a few kilometers from PFAS point source Only a small proportion of Sweden s fire training sites have been investigated PFAS levels are poorly investigated at most point sources Lack of information on concentrations of the other PFAS may lead to an underestimation of the risk to human health and the environment. 4

5 Sources in Sweden (SEPA report) Fire fighting training areas > 300 municipal firefighting training areas have been in use (likely many more) > 28 main firefighting training areas at airports (+ auxiliary training areas) 64 fire brigade stations where training activates supposedly occurred 4 national training areas + industries, waste sites and tank farms (some have their own fire training sites) Fires 9000 fires where fire fighting foam has been used where > 100 l was used. No info on class A or B foam. Industrial Metal surface treatment, < 30 sites, investigations indicate lower concentrations than firefighting areas/sites Textiles, electronics, hydraulic fluids etc. unknown levels Landfills Waste Water Treatment Plants PFOS in wwtp sludge, 1-50 mg/kg TS PFOS in wwtp outgoing water, 5-50 ng/l PFOS in waste leachate ng/l High volume chemical group present in many products Present in most (all?) outgoing waters Most important diffuse source to the environment, causing elevated background concentrations (+ atmospheric deposition) 5

6 Sources Possible PFAS sources Confirmed PFAS sources 6

7 Focus of PFAS investigations in Sweden 1. Soil and groundwater at fire fighting training areas 2. Drinking water supplies in the vicinity (km) of point sources 3. Surface water in the vicinity (km) of point sources 4. Drinking water supplies in general 5. Biota in vicinity of point sources 7

8 SEPA Study: Screening + compilation of previous measurements Average PFOS concentrations surface water Average PFOS concentrations ground water High Background Concentrations > AA EQS Total PFAS unknown

9 Screening of water supplies Ground water supplies PFAS detected in 36 of 193 water supplies (19%) Frequency of detection: PFOS >> PFOA > 6:2 FTS, PFBS, PFPeA, PFHpA Surface water supplies PFAS detected in 10 of 27 water supplies (37%) Frequency of detection: PFOA > PFOS > 6:2 FTS = PFHxS = PFHpA Natural infiltration water supplies PFAS detected in 6 of 12 water supplies (50%) Frequency of detection: PFOA > PFOS > PFBS 9

10 Site Investigations SWECO > 20 municipal and airport FFTAs Industrial sites + waste sites > 400 drinking water supplies > 200 surface water samples > 350 groundwater samples > 300 soil samples > 100 sediment samples > 50 fish + Many more sites by other consultants Until 2016, only focus on investigations 2017 site remediation and pilot studies also started 10

11 Occurrence in soil (selected sites) Highest concentrations at each site at central part of training area: mg/kg Median highest concentration: mg/kg no clear correlation to size or time of operations Distance of influence from central part of training area : 5 50 m possibly related to wind Affected area around central part of training area : m2 likely related to wind and exercise characteristics Depth of maximum concentration: surface to several m, down to GW interface very site specific leaching dependent on ph, negatively charged clay/silt, TOC etc. PFAS composition sometimes changes over depth shorter chain with increasing depth! total PFAS concentration unknown, 1000s of PFAS not analyzed! Further soil investigations over larger areas at airports often find PFAS, but at low concentrations mixed usage over long time 11

12 Guideline Values Soil Sweden (mg/kg) Risk receptor Sensitive Land Use (residential, gardens etc.) Adjusted health based guideline value Oral intake soil Dermal exposure Dust inhalation exposure Vapor inhalation exposure Drinking water exposure Intake of plant exposure Soil biota Groundwater protection Surface water protection Preliminary Guideline Value Less Sensitive Land Use (Industrial, Office etc.) 12

13 Interrim Guideline Values Soil Sweden (mg/kg) Risk receptor Sensitive Land Use (residential, gardens etc.) Adjusted health based guideline value Oral intake soil Dermal exposure Dust inhalation exposure Vapor inhalation exposure Drinking water exposure Intake of plant exposure 0.6 -?? Terrestrial biota Groundwater protection Surface water protection Preliminary Guideline Value Less Sensitive Land Use (Industrial, Office etc.) 13

14 Risk Assessment Soil Guideline values for soil generally not to be used for final decisions on remedial needs in depth risk assessment needed Recommended that sum PFAS 11 is compared to PFOS guideline Value PFAS (until now) generally regarded as a groundwater and surface water issue The guideline values for soil mostly controlled by the risk to surface water and groundwater Exception protection of terrestrial biota (3 mg/kg) Governed by effects on secondary predators and bio concentration in the food chain Protects 95% of all species which is more conservative than usual in Sweden Low soil guideline values indicates an issue in surface soil at sites where soil has not been considered a major problem in itself Source zone remediation solves the problem 14

15 Occurrence in shallow aquifer groundwater (selected sites) Highest concentrations at central part of training areas: ng/l Median highest concentration: ng/l several smaller FFTAS with very high concentrations, and several large with lower concentrations Size of operations is not a good predictor of groundwater concentrations Longer plumes show clear PFAS differentiation along flow direction: Lower chain PFAS PFAS plume composition a result of precursor transformation Site Geology Plume length / length of GW contamination Airport FFTA 1 Alluvium, permeable 10 km Airport FFTA 2 Sand < 3 Km Airport FFTA 3 Peat, moraine, silt m Airport FFTA 4 Sand, Calciferous bedrock 1-2 km Airport FFTA 5 Sand/Silt > 500 m Rescue Services FFTA Sand < 500 m (plume reaches small stream) 15

16 Occurrence in deep bedrock aquifer groundwater > 50% of investigated sites has PFAS in deep groundwater Mechanism uncertain: Large amounts of foam used causing product intrusion? Not DNAPL, but residual coherent product may have similar behavior? Very water soluble contact with deep and shallow aquifer water will contaminate deeper aquifer 16

17 Drilled drinking water wells in calciferous carst bedrock at m bwg Sandy moraine soil layer on top 11 PFAS ng/l 17

18 Drinking water risk levels TDI based drinking water guidance values for 11 PFAS developed by the Swedish Food Administration. Values for infants and pregnant women: >90 ng/l; 90% of exposure allowed from other sources. Measures to reduce concentrations has to be initiated > 900 ng/l; 0% exposure allowed from other sources. Consumption of water should cease immediately Several major drinking water supplies shut down in Sweden due to high levels of PFAS. Sources known to be fire fighting training areas Screening of human population (several thousand) at one municipality have shown elevated blood levels of PFAS associated with elevated levels in drinking water. Source known to be fire fighting training area. 18

19 Results surface water (selected sites) Dilution (based on hydrological modelling) accurately predicts PFAS concentration gradient in a small stream 19

20 Surface water risks. If small and/or isolated surface waters are present within the influence radius (km) risks needs to be evaluated and biota measurements will be needed. In Sweden several such lakes has been closed down fishing prohibited Larger water bodies. FFTA point sources probably less important than background loading from WWTPs, atmosphere etc. 20

21 0.65 ng/l AA-EQS Explained + Low TDI: Ämne TDI (mg/kg kroppsvikt och dag) Kadmium PAH L 0.03 PFOS Assumption of one person of 70 kg eating 115 g fish per day and that only 10% of daily exposure is allowed from fish an acceptable concentration in fish (EQSbiota) = 9.1µg/kg + High BCF from water to fish (=2800) and high biomagnification from fish to humans (=5) 9.1/(2800*5) = ug/l = 0.65 ng/l These assumptions are being challenged as being over-conservative

22 Differences Sweden- Denmark Danish geology (clay) and geohydrology may imply lower degree of transport to groundwater aquifer...or a delayed transport since the perflourinated PFAS do not degrade Sweden, have a relatively centralized drinking water production Denmark has a decentralized drinking water production 22

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