Passive Samplers for PFAS in Surface Water and Air

Rainer Lohmann,University of Rhode Island

Passive samplers• Passive samplers measure activity of pollutants, e.g.

the dissolved/gas phase

• uptake by diffusion

• advantage – no operational separation of particulate and dissolved phase

• need to know Kpassive-water (T, sal) or Rs, sampling rate

• Cdiss = Cpassive /[Rs x t] (linear uptake)

• Cdiss = Cpassive / Kpassive-w (equilibrium sampler)

Atmosphere

Water

Contaminated Sediments

(Cfree)

TYPES OF PASSIVE SAMPLERS ANDHOW THEY WORK

8

Where can we use passives?

Why passives might be useful• Time-integrated concentrations• Pre-concentrations already in field• Less handling in laboratory• Proxy for bioaccumulation

(Cerveny et al., 2016)

(Dreyer et al., 2010)

Something in the air..… and in your blood

(Makey et al. 2017)

Testing of Polyethylene Sheets as Passive Samplers for Volatile PFAS in Indoor Air

Maya Morales-McDevitt et al.

02000400060008000

1000012000140001600018000

1 2 4 8 15 21

pg/g

(PE)

Days

6:2 FTOH

50 um25 um

(Dixon-Anderson and Lohmann, 2018)

11

PE-tube sampler for PFASs in GW

b)a)

(Kaserzon et al., 2019)

Time series WWTP study, June 2018

0

10

20

30

40

50

60

70

80

90

efflu

ent c

once

ntra

tion(

ng/L

)

Fields Point WWTP effluent

PFBA PFBS PFPeS PFOA 6:2-FTS PFHpS PFOS PFNS0

10

20

30

40

50

60

70

80

2 4 8 16 29

Pass

ive

sam

pler

coc

n (n

g/sa

mpl

er)

time (days)

PS in Fields Pt WWTP Effluent PFBAPFPeA

PFBS

PFHxA

4:2-FTS

PFPeS

PFHpA

PFHxS

PFOA

6:2-FTS

PFHpS

PFNA

Sum 25 PFAS

9Christine Gardiner et al.

Lab Validation of PFAS Passive Sampler

Uptake as function of• water flow

velocities • temperatures • Biofouling

conditions • Salinity • DIC

Potential PFAS Contamination sites in Guam(Barry Kim et al)

• High occurrence of PFASs.

• Testing soil and water for PFASs

• Wet vs dry season

• Identify sources

3

Fiber Passive Sampler for PFAS Detection at AFFF

Impacted Sites?

SPME fiber coated with polyacrylate (24 hours for equilibrium)

R² = 0.9971

R² = 0.99

R² = 0.9826

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4 5 6 7 8 9 10 11 12 13

log

KP

A_

W

carbon chain lengh

PFAAs PFSAs FTSs

0.0

1.0

2.0

3.0

4.0

0 1 2 3 4 5 6

log

KP

A_

W

pH

PFOA

8

(Becanova and Lohmann, in prep)

✓ FIBER to predict physical-chemical properties of PFAS?

12

Birds reflect…• open ocean• urbanized estuary • an estuary downstream

of a fluoroproductproduction center

Anna Robuck et al.

Imag

e cr

edit:

Ann

a R

obuc

k, U

RI-G

SO

Great Shearwaters

Next steps•Passive samplers as useful tools for PFAS activity and transfer• For air, passive air samplers are operational• Gas-phase sampling to be developed• Several options for dissolved PFASs• Porewater samplers to be developed• Proxies for bioaccumulation?

STEEP is funded under award number P42ES027706. More information about STEEP is available at: www.uri.edu/steep/

Thanks to- NIEHS, of course- RI C-AIM for HPLC-MS/MS; - RI STAC and SERDP for passive sampling tube work- Partners/collaborators, grad students

Questions?