Hazard assessment of fluorinated alternatives to long-chain PFASs

Ian Cousins, ACES - Department of Environmental

Science and Analytical Chemistry

Helsinki Chemicals Forum

Helsinki, Finland, 26th May 2016

Background

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• Swedish Chemicals Agency (KEMI) identified >3000 PFASs (June 2015)

• Increasing trend in patents and new PFASs

• <2% registered under REACH

• >50% PFASs have unknown uses, little information on quantity of use

Industry phase-outs and replacements

Products (low molecular weight and polymers) containing long-chain perfluoroalkyl moieties

Mainly replaced with alternative products containing or degrading to form

Short-chain PFAS moieties Perfluoro(poly)ether moieties

CF2 CF2OPFCA < 7 perfluorinated carbonsPFSA < 6 perfluorinated carbons

PFCAs (≥ 7 perfluorinated carbons)

PFSAs (≥ 6 perfluorinated carbons)

8:2 FTOH

3

Some fluorinated alternatives

Are these fluorinated alternatives less hazardous and more sustainable substances than those that they replace?

O

F FF

F

F O

F F

F F F

F F

O

OH

O

F F

F FF

F

F

O

OH

F

FFF

O O

O

OH

FFF

FFF

FF

FF F

F

O

FF

Cl

F F

F F

OO

F F

F F F FF

Cl

F O

O

OH

F FF

FFF

FFF

FF F

OO

F F F F

F FF

F

F

O

OH

FFPer

fluor

oeth

er c

arbo

xylic

aci

ds (P

FEC

A) OH

F FF

F

F

F F

F FF

F

F

F FF F

OH

F FO

F F

F F

F F

F F

F F F F

ClF

F SO

OOH

F F

O

F F

F F

F F

F F

F F F F

FF

F SO

OOH

F F

RM610

RM620

8:2 FTOH replacements PFOS replacementsPFOA replacements & other uses

F-53

F-53B

Adona

GenX

Unknown

Unknown

EEA

Sho

rter c

hain

Per

fluor

oeth

er s

ulfo

nic

acid

s (P

FES

As)

4Wang et al., (2013) Environ. Int., 60, 242-248.Wang et al., (2015) Environ. Int., 75, 172-179.

Hazard assessment: fluorinated alternatives

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  Short-chain PFAAs Known PFECAs and PFESAs

P

LRT

B

T

vP vP

High LRT High LRT

Low B*

*B decreases with perfluoroalkyl chain length

B is not relevant for vP chemicals

• vPvB criteria aim to protect against poorly reversible exposures

• But contaminant levels in organisms poorly reversible if:1. slow elimination (related to B), or2. external exposure poorly reversible (related to vP, but not B)

• Drinking water aquifers contaminated with short-chain PFAAs – Groundwater highly contaminated for decades to centuries– German Environment Agency (UBA) suggest Persistence,

Mobility, Toxicity criteria

6Cousins et al., (2016) Environ. Int., in press.

Planetary boundary threats

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PFASs are potential planetary boundary threats for chemical pollution:1. Unknown effects2. Planetary pollution potential3. Pollution poorly reversible

Rockström et al. Nature, 2009, 461, 472-475. Persson et at., ES&T, 2013, 47, 12619-12622.MacLeod et al. ES&T, 2014, 48, 11057-11063. Steffen et al., Science, 2015, 347, 6223.

Conclusions

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• Lack of data for many PFASs so risks unknown

• All PFASs are “ultimately” highly persistent and many are mobile.˗ Expect global poorly reversible contamination

˗ Not sustainable

• Global risk reduction not possible if contamination is not reversible.

• Society may want to be precautionary and substitute non-essential uses of PFASs.

The Helsingör and Madrid Statements

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Contains the authors’ views on the on-going transition to fluorinated alternatives