Two new certified reference materials for analysis of toxic elements in plastics

toxic elements
Electronic components, such as the computer circuit on the photo, contain plastic parts which can hold traces of toxic elements. © Fotolia, Olexandr

The JRC released two certified reference materials (CRMs) that will ensure the quality of results from testing toxic trace elements in plastics used for electric and electronic equipment. The two are upgraded versions of previous CRMs and are now able to identify – besides lead, cadmium, mercury and chromium – also six other elements. This will support the implementation of EU legislation which requires limiting those compounds to ensure the protection of consumers and the environment.

In determining whether a product or raw material complies with the legislation, reliable measurements are necessary, both for routine quality control and the calibration of analytical instruments. Bearing this need in mind, the European Commission already in 2001 funded a project for the production of two certified reference materials for trace elements in plastics. Due to the high demand for these materials, replacements were released in 2007, which in turn are now close to exhaustion.

The JRC has produced two new reference materials of low-density polyethylene (LDPE), coloured with pigments containing the relevant elements. Homogeneity and the stability of the materials were demonstrated under extreme conditions. Certified values, not only for lead, cadmium, mercury and chromium, but also for six other potentially hazardous elements (arsenic, bromine, sulphur, antimony, tin, zinc) were assigned in a joint effort comprising 13 laboratories in Europe and Australia. The release of the two certified reference materials, named ERM-EC680m and ERM-EC681m, will allow laboratories to continue the implementation of this important legislation.

The two certified reference materials will support the implementation of Directive 2011/65/EU (known as “RoHS 2”, from restriction of the use of certain hazardous substances in electrical and electronic equipment)Directive 94/62/EC (referring to packaging material), and Directive 2000/53/EC EU (on old vehicles) – all having as objective to limit toxic elements such as lead, cadmium, mercury and hexavalent chromium.