The UK response to PFAS contamination: Distilled thoughts on the HSE/ EPA RMOA

Preamble

On Tuesday this week the UK Health & Safety Executive (HSE) and UK Environmental Protection Agency (EPA) published their 'Analysis of the Most Appropriate Regulatory Management Options' (RMOA) for PFAS, which is a 'non-binding technical document' well over one year after the call for evidence, to which Stevenson Process Technology responded, closed. Maybe it has taken such a long time because the report is very long, running to 192 pages plus extensive appendices. At last we have some activity from a quango after a very long period of silence and that, in itself, provides at least some succour. I was getting worried; in July last year I discovered that the board of the Water Services Regulation Authority, or?Ofwat, had never collectively heard of PFAS. I have needed to read all of the document, and I thought some in the PFAS remediation community might find my distilled thoughts about the document of some interest. I'm not a toxicologist nor am I a chemist; my thoughts are from my perspective as chemical engineer, and specifically one who is currently engaged in developing adsorptive processes for removal of short-chain PFAS from water, and thus I can only comment upon topics upon which I have expertise. I leave claims of omniscience with respect to PFAS to others. I endeavour to resist pointing out the very many errors, particularly scientific, in the document in the interests of brevity.

The call for evidence was, in itself, a disappointment to me. It was, at the same time, very focussed upon the applications of PFAS (along with estimates of consumption) in a questionnaire, and very broad in that it didn't specifically ask about remediation methods. It seemed to me like it was an exercise to lay the foundations for exceptions to any regulations that may come in the future. In fact, it is explicitly stated that the 'environmental risks arising from historic or discontinued uses of PFAS that are no longer permitted' are without the remit of the exercise, so I suppose that it is inevitable that the focus is on how PFAS will continue to be used rather than remediation, although some might think that the wrong question is being addressed. That the term 'forever chemicals' is used in the Executive Summary possibly betrays the lack of interest in remediation. Why bother trying to clean-up something that will be there forever? As it happens, PFAS are not 'forever chemicals' because we know how to practically concentrate PFAS in water before degrading the molecules. The use of the term 'forever chemicals' for PFAS is as lazy as it is incorrect (and I say that as somebody who has previously used it, but who is now reformed), and gives those who would rather not bother cleaning-up the mess a reason for inaction.

As a codicil to this preamble can I define some acronyms and initialisations that are used in the RMOA that are not defined, at least not immediately. REACH is a European Union regulation entitled 'Registration, Evaluation, Authorisation and Restriction of Chemicals'. UK REACH is the corresponding post-Brexit regulation. FFF is eventually defined on p. 26 as firefighting foam, but this can be used in the same context as 'fluorine-free foam' here. Don't be daft: Eschew undefined acronyms and initialisations.

Straight to the conclusions (of the Executive Summary):

Unfortunately nothing material is concluded or recommended in the RMOA, at least to my reading. There is plenty of equivocation, and it appears that the door is being left open for exceptions and special pleading. The primary conclusions can be found in the Executive Summary of the RMOA document which I repeat herein in italics, with my commentary to each conclusion in non-italics: (The syntax inconsistencies are not due to me.)

The Agency concludes that it would be appropriate, considering the Precautionary Principle, to initiate some or all of the following risk management measures with regard to certain uses of PFAS:

Conclusion 1

Preparation of Annex XV dossiers to potentially support one or more restrictions of PFAS under UK REACH, including:

a. the use and disposal of FFF where non-PFAS alternatives are available,

b. other wide dispersive uses such as the application of coatings or use of cleaning agents,

c. the manufacture and placing on the market of consumer articles from which PFAS are likely to be released into air, water or soil, or directly transferred to humans. This includes textiles, upholstery, leather, apparel, rugs and carpets, paints, varnishes, waxes and polishes, cleaning products. Consideration may be given to other consumer articles if other gaps are identified in consultation with other legislative regimes such as food contact materials.

For those who don't know, an 'Annex XV dossier' is the document required by REACH regulations to give justification for the nomination of a species to be a 'substance of very high concern (SVHC)'.

Thus, the RMOA is recommending that evidence is collected to maybe support regulatory restrictions on the use of AFFF (Aqueous Film Forming Foam, which are stabilised by PFAS), where there are alternatives. This is surprising to me. I'm not an expert in firefighting, but I thought that there emphatically are alternatives. Last year I chatted to a former firefighter who was serving at RAF Akotiri when AFFF was first introduced to the British military in the 80s, and he told me how delighted he was about it since it replaced a substance that smelt of a 'baby's nappy'. I hear of AFFF alternatives regularly on forums such as LinkedIn. There is no shortage of non-PFAS alternatives, but the RMOA equivocates, and this is, to me, demonstrates a lack of commitment to tackle the problem.

The same goes for coatings and cleaning agents. There will always be alternatives, although these may be less effective, or more expensive, than the PFAS-containing product. One can always make a special plea to continue using PFAS-containing product for one application or another, but this doesn't do anything to discontinue the use, and therefore environmental contamination, of PFAS. The RMOA demonstrates a lack of commitment, when it would have been as easy to make a positive statement, and this doesn't engender confidence within me.

Conclusion 2

UK REACH authorisation of PFAS used in processing aids in the manufacture and processing of fluorinated polymers

I am not sure that I understand what is meant here, either if the second conclusion is taken in isolation, or after the sentence 'The Agency concludes.....following risk management measures with regard to certain uses of PFAS:' Commercial uses of fluorinated polymers include PTFE and Teflon, for instance. Is the ground being prepared to allow for the continued manufacture and processing of these products? It sounds like it to me. So, business as usual in the UK?

Conclusion 3

Further evaluation and investigation of substances that have been highlighted to be of concern

a. Trifluroacetic acid, EEA-NH4 and perfluoroalkanes and perfluorocycloalkanes

Last year I noted that the work of Trang et al. (2022), who proposed a chemical mechanism for the degredation for perfluorocarboxylic acids (PFCAs), was heralded by many commentators, including a spokesperson of the Royal Society of Chemistry, as a 'breakthrough' in the treatment of PFAS contaminated water. I actually read, and tried to understand, the paper, and I was more circumspect, primarily because of the glacially-slow kinetics; my analysis of the primary kinetic data is reported here. However, the primary degradation product of Trang's reaction is trifluoroacetic acid (TFA), and this appears as the first compound in the RMOA's hit-list. By the RMOA's own definition, TFA is a PFAS because is has one fully fluorinated methyl carbon atom, and yet it does not appear in the US EPA's recently proscribed PFAS, nor is it in the 'EU Directive-20' or Swedish 'SLV-11' suites of PFAS of concern, for instance. (The RMOA discusses a developmental toxicity study on rabbits that apparently show that TFA causes abnormalities, but no reference is given, at least not that I can find.) If limits on drinking water concentrations of TFA are ever to be enforced in one or other jurisdiction, then the need to develop methods for the adsorptive removal of short-chain PFAS, and there is no shorter than TFA, will become even more urgent. Stevenson Process Technology is currently developing a method to do just this, and will report results of laboratory investigations soon. Don't hesitate to make contact if you are interested in such process developments.

Conclusion 4

Continued collaborative work across government and with external stakeholders to bring together work on PFAS strategically, including:

a. A review of the F-gas regulations to determine whether additional PFAS registered under UK REACH should be brought within scope

b. Development of statutory standards for PFAS in drinking water in England and Wales

'Continued collaborative work', eh? Business as usual, by definition. Note that the recommendation is for a development of statutory standards, rather than implementation of them.

Summary of my thoughts

The UK is a very long way behind the USA with respect to government-led responses to the problem of environmental PFAS contamination. Last month, the US Government announced legally enforceable concentration limits on six PFAS species. One can question as to why the US EPA has chosen these drinking water criteria (for instance, I suspect that very short-chain PFAS have been excluded because they are very difficult to adsorptively remove, although I think that I have just developed a process so to do), but at least some intent has been demonstrated, and there will be some improvement in water quality in some places. The Government of Australia is taking positive action at contaminated sites, and the joint Heads of EPA of Australian states and NZ in 2020 published a PFAS National Environmental Management Plan which included advisory drinking water criteria for PFOS, PFOA and PFHxS.

In contrast, the UK has published this RMOA which will not be the catalyst for any concrete action that will reduce PFAS contamination of watercourses, or improvements in the quality of PFAS-impacted drinking water. I have been told anecdotally, the the West Midlands, and specifically Kidderminster, is particularly badly affected by PFAS because of the significant local carpet manufacturing industry. This is a, at least circumstantial, exposition of cause and effect. The RMOA is only brave enough to suggest the preparation of a dossier that potentially with restrict the use of PFAS in the carpet industry, for instance. It simply isn't good enough. (You might like to take a look at Fig. 3.4 on p. 32 of the UK EPA's Chief Scientist's report 'Poly- and perfluoroalkyl substances (PFAS): sources, pathways and environmental data' for a cartographical representation of PFAS contamination in the UK, and look to see where Kidderminster would be.)

The UK water industry is currently in a parlous position, particularly with discharge of polluted water to surface watercourses. Government quangos, such as the EPA and Ofwat, appear impotent to do anything about it. Perhaps then it shouldn't come as a surprise to the PFAS remediation community that the long-awaited RMOA is so toothless. But it really isn't good enough, in my opinion.

Do please let me know if you think that I've misinterpreted something with respect to the RMOA. And do give me a call if you would like a chat about adsorptive methods of removal PFAS from water.