The addition of D4, D5 and D6 to the Candidate list under REACH is disproportionate and endangers critical beneficial uses

The silicones industry strongly believes that the recent Member State Committee decision (ED/61/2018) to add D4, D5 and D6 to the list of Substances of Very High Concern (SVHC) does not take full account of the whole body of scientific evidence, should have recognised already applicable or on-going regulatory activities, and puts at risk numerous beneficial uses including in the healthcare, electronic and energy efficiency sectors.

The decision should have given more consideration to the following factors:

  1. An SVHC listing does not result in any additional environmental benefit, considering the REACH wash-off restriction already adopted and the ECHA intention to consider further restrictions of D4 D5 and D6. Monitoring results show that concentrations of D4 and D5 in wastewater are already typically below the predicted baseline, and in the case of D4, already consistent with predicted post-restriction levels.
  2. In order to consider all the data available on these unique hybrid organic-inorganic substances and appropriately address the concerns raised by some scientists on their persistence (P) and bioaccumulation (B) assessment, the industry believes that we need to find an appropriate platform to resolve scientific divergences and remaining uncertainties, to allow for an in-depth review of the science available on these substances in line with advancements in the understanding of persistence and bioaccumulation since the criteria were developed. Up-to-date scientific data demonstrate that these unique chemicals behave differently from what is predicted under current PBT regulatory criteria and that the methods used to assess P and B may need to be reviewed and updated, a position supported by several eminent scientific experts from around the world. For example, in the case of D4, D5 and D6, the methodology may significantly overestimate bioaccumulation using the bioconcentration factor (BCF) but there is also a risk of underestimating bioaccumulation in the case of other substances. Accurate PBT/vPvB assessment based on the latest science should be the prevailing policy driver.
  3. Several other regions, including for example Canada and Australia, have conducted a thorough environmental assessment based on the same data set and concluded there is no need to regulate D4, D5 and D6. Environment Canada, having reviewed the environmental data available for D4, has not imposed any product concentration restrictions on the use of D4 in any application.
  4. Identifying D4, D5 and D6 as SVHCs is damaging to investments, innovation and competitiveness, as it causes considerable uncertainty for customers on a global level.

Silicone polymers rely on D4, D5 and D6 as building blocks (monomers) for their manufacturing. Silicone materials are widely used and difficult to substitute because of their durable, safe and highly effective mechanical, optical and thermal properties. Critical applications of strategic importance to the EU include construction, transportation, lighting, alternative energy, electronics and medical uses.

“The silicones industry is committed to responsible stewardship and will continue to promote environmental responsibility through developing and supporting independent science and monitoring studies. The industry will also continue to work closely with regulatory authorities around the globe to ensure that silicones can continue to be used with confidence and their innovation potential preserved”, commented CES’ general manager, Dr. Pierre Germain.

For more information, please contact:

CES Manager, Evelyne Frauman // Email: // // @SiliconesEU

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