Question: I've heard some confusing information about substances of very high concern (SVHCs) in products made from glass — that some substances "don't count" if they're in glass, at least in some situations. Can you explain? Also, how does this affect Substances of Concern In articles, as such or in complex objects (Products) (SCIP) requirements?
Answer: This question usually concerns one of two substances: diboron trioxide (in borosilicate glass) or lead (in lead crystal glass). In either case, it's important to remember that the SCIP database and SCIP notifications are based on the European Union (EU) Waste Framework Directive (WFD) rather than the Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH) Regulation, even though the REACH SVHC list is used to identify articles containing hazardous substances that must report information to the SCIP database.
Under the REACH Regulation, glass articles are manufactured from glass (considered a substance), which is itself manufactured from various raw materials. The raw materials used to manufacture different types of glass contribute in different ways to the core structure of the resulting glass. As a result, some component substances are synthesized and become part of the final glass substance, while others are still considered to be present as distinct substances in the finished glass.
Diboron trioxide (B2O3) in glass: Diboron trioxide, along with silicon dioxide, is an intermediate "network former" substance in the production of borosilicate glass. The final product (borosilicate glass) is itself a new substance, synthesized from the raw materials but no longer containing them in their original independent states. When articles are produced, their component substance should correctly be listed as borosilicate glass under the REACH Regulation. Diboron trioxide should not be listed as a component, unless it remains as a free substance (impurity) in the article at a concentration greater than 0.1 percent weight over weight (w/w).
Since B2O3 is not a component substance of borosilicate glass articles (except in cases of residual impurity), companies would not be required to communicate about the presence of B2O3 under REACH Article 33(1) or to report the presence of B2O3 to the SCIP database.
It's important to understand that this is due to diboron trioxide's intermediate role in the formation of borosilicate glass; B2O3 is only present in the finished glass substance as an intrinsic part of the molecular network (from which it cannot be separated), not as a distinct substance on its own.
Lead in glass: Leaded glass or lead crystal contains lead(II) oxide (PbO), often at concentrations over 20 percent w/w. Unlike diboron trioxide, lead oxide remains as a distinct component of leaded glass and is considered to be present in lead glass articles. This is because lead oxide may be separated from leaded glass in the form of metallic lead, which is also an SVHC.
As a result, lead oxide in glass is still considered an SVHC, with all the associated responsibilities under the REACH Regulation and relating to the SCIP database.
Content is current as of 2020-11-20.