Anything from whisks and washing machines to power tools and PCs can be classed as WEEE at their end of life stage, and most are now recycled as they usually contain many valuable materials or elements which are difficult to attain from natural sources.
However, European legislation states that recycled plastics from WEEE may not be used for the production of food-contact articles within the continent because they contain brominated flame retardants (BFRs), chemical combustion inhibitors which can migrate into food upon contact.
Despite the introduction of these laws, researchers in the Czech Republic and Germany have applied several independent analytical methods to prove the existence of WEEE relevant substances within black polymeric food-contact articles, such as thermocups and black kitchen utensils, purchased on the European market.
The authors focused not only on the presence of WEEE specific non-rare earth elements such as copper, iron and lead, but also the presence of WEEE specific rare earth elements (REEs) like dysprosium, lanthanum, neodymium, praseodymium and yttrium.
Within their study, the authors were able to identify the presence of bromine in seven of the ten food-contact articles examined and four of these contained REEs -- typically found in the chemical composition of LED diodes, magnets and LCD screens. Additionally, in all cases when bromine was detected at higher concentrations, antimony, which is often combined with BFRs as a very effective flame retardant in electronic equipment, was also detected. Furthermore, foreign polymers were detected in the main polymer matrix of all ten items.
While this study focused on a very small number of samples, the authors wish to address their concern to the scientific community, policy makers and control authorities regarding the abundance of WEEE related chemicals present in the food-contact articles examined, and warn that that this preliminary data may reflect the actual situation on the European market.
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