Authored by: Dr. Paul Goodman, Principal Regulatory Consultant, RINA
The European Chemicals Agency has proposed four substances to be added to the REACH Candidate List as Substances of Very High Concern (SVHC). Three of the substances are reported to be reproductive toxins and the fourth (PFBS) is a possible endocrine disrupting substance, harmful to the environment and humans, as well as being fairly persistent.
The current Stakeholder Consultation, ending on the 18th October 2019, aims to confirm whether the substances meet the Article 57 criteria for addition to the Candidate List, e.g. if they are category 1A or 1B reproductive toxins. Details on the substances and typical uses are as follows:
- 2-benzyl-2-dimethylamino-4′-morpholinobutyrophenone (CAS 119313-12-1): This substance is used as a photoinitiator added to UV curable inks, toners, adhesives, resins, paints and other coatings. It may also be used in fillers and adhesives. It is used in the manufacture of many products including electronic equipment. This substance is added typically at 0.5 to 5% of the cured material which may be a coating on an article or printed ink and so the concentration in simple articles (as defined by REACH) could be less than 0.1% by weight. However, when it is used as a thicker section of cured polymer the concentration it is more likely to exceed 0.1% of the article.
- 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one (CAS 71868-10-5): This is a photoinitiator added to UV curable inks, toners, lacquers, paints and resins. It may also be used in solder masks and etch resists in glass fibre composites. It is used at similar concentrations to 2-benzyl-2-dimethylamino-4′-morpholinobutyrophenone so may occur at <0.1% in thinly coated articles, but when used as a thicker section it is more likely to exceed 0.1% of the article.
- Diisohexyl phthalate (CAS 71850-09-4): This is another dialkylphthalate that has been added to the Candidate List. Dihexyl phthalate is already listed. This substance is a plasticiser so may occur in flexible polymers and rubbers, inks, lacquers and sealants. It is also reported to be used in vehicle steering fluids and in auto transmission lubricants.
- Perfluorobutane sulfonic acid (PFBS) and its salts (No unique CAS number as it is group of substances): These substances are used as water soluble surfactants and in stain and water resistant coatings (including as a substitute for perfluoroctyl sulphonate – PFOS, which is now banned in many countries).
If these substances are determined to be eligible to be added to the Candidate List, they could be added with the next update to the Candidate list due in January 2020.