A UN expert committee has recommended global action on three fluorinated substances, PFOA, PFOS and PFHxS.
The review committee for the Stockholm Convention on persistent organic pollutants (POPs) met at the end of September with the aim of agreeing recommendations for the substances, ahead of next year's meeting when decisions are expected.
The three chemicals, used in industrial applications and manufacturing processes for their water and oil resistance, are at different stages of the treaty process. They have been identified as persistent, bioaccumulative and reprotoxic.
Inclusion and exemptions
At the meeting in Rome, the POPs Review Committee (POPRC) recommended listing PFOA in Annex A of the treaty, which calls for global elimination. With this, ten time-limited exemptions were recommended (see box).
For PFOS, which was added to the convention in 2009, the committee recommended removing exemptions for the following applications:
- photo-imaging, photo-resist and anti-reflective coatings for semiconductors;
- etching agent for compound semiconductors and ceramic filters;
- aviation hydraulic fluid;
- certain medical devices;
- photo masks in semiconductor and LCD industries;
- hard and decorative metal plating;
- electric and electronic parts for some colour printers and colour copy machines;
- insecticides for control of red imported fire ants and termites; and
- chemically driven oil production.
A five-year phase out has been proposed on exemptions for fire fighting foams and metal plating uses, which are controlled through a closed loop system. The only time-unlimited exemption without a recommended change is for insect bait for the control of leaf-cutting ants. This use refers to a pesticide called sulfluramid that degrades to PFOS.
In addition, the committee agreed to take the substance perfluorohexane sulfonic acid (PFHxS), its salts and related compounds forward to the next review stage, which requires a risk management evaluation. At its next meeting, and following the evaluation, it will make further recommendations on whether the substance should be listed and how it should be controlled, as well as any exemptions to be applied.
Dr Sara Brosché, science adviser for the global network of public interest organisations, Ipen, welcomed the recommendations but said: "The fluorine industry replaced one bad chemical, PFOS, with another bad chemical, PFHxS. That’s cynical self-interest that damages human health."
"This entire class of fluorinated chemicals is too dangerous to deal with one at a time and countries should take action to address them as a class and remove all of them," she added.
In response, industry group the Fluorocouncil, an arm of the American Chemistry Council (ACC), said: "The broad assertions made by a few parties at POPRC relative to PFAS as a class are not founded in science and not supported by the multiple reviews and approvals of the newer PFAS alternatives by many regulatory authorities."
'This entire class of fluorinated chemicals is too dangerous to deal with one at a time and countries should take action to address them as a class and remove all of them,' Dr Sara Brosché, Ipen.
However, according to Ipen, the committee recommended avoiding fluorinated alternatives to PFOA and PFOS for use in fire fighting foams. It said this was because of their "persistency and mobility as well as potential negative environmental, health and socioeconomic impacts."
A committee of the UN's Rotterdam Convention, which governs the prior informed consent (Pic) of the importation and exportation of hazardous chemicals, also recommended listing PFOA last month.
PFAS substances have come under fire amid mounting public concern and political controversy surrounding them. Subcommittees for the US Senate and House committees have both held hearings on the chemical group.
And according to a recent statement by over 30 regulators and academics, the high persistence of the chemicals in the environment may not be adequately reflected in their current regulation around the world.
Recommended phase out times for PFOA exemptions:
- three exemptions for semiconductor manufacturing (equipment or plant infrastructure, legacy equipment, photo-lithography or etch process);
- photographic coatings applied to films;
- textiles for oil and water repellency to protect workers;
- invasive medical devices;
- implantable medical devices; and
- firefighting foams.
- for manufacture of semiconductor or related electronic devices; refurbishment parts containing fluoropolymers and/or fluoroelastomers with PFOA for legacy equipment or legacy refurbishment parts.
- the use of PFOI (a PFOA-related substance) to make PFOB for producing pharmaceutical products "with a review of continued need for exemptions".