In their article in the Journal “Analytical Methods” , Dr Ines Masuck, Dr Christoph Hutzler and Professor Dr Dr Andreas Luch from the German Risk Assessment Institute (BfR) in Berlin point out that allergenic fragrances are one of the main causes of contact dermatitis in children. The BfR scientists report that the revised European Directive on the safety of toys 2009/48/EC  therefore bans 55 fragrances, although it permits up to 100 µg of the fragrance per gram of material when this is technically unavoidable under good manufacturing practice.
The aromatic compounds that are banned or are only permitted in limited concentrations include, for example, d-limonene, linalool, benzyl alcohol, citronellol, methyl heptine carbonate, geraniol, citral, hydroxy-citronellal, cinnamal, anisyl alcohol, cinnamyl alcohol, eugenol, isomethyl ionone, isoeugenol, lilial, amyl cinnamal, farnesol, lyral, amylcinnamyl alcohol, hexyl cinnamaldehyde, benzyl benzoate, benzyl salicylate, benzyl cinnamate and coumarin. There should be no expectation that the packaging will indicate whether any of these substances have been used as a additive. It is not possible to conclude, on the other hand, they are not present because they are not permitted. Be very careful has to be the motto. Some manufacturers who have not committed themselves to compliance with a quality standard tend on occasions to try and improve their products by adding banned substances.
Quality control is important to monitor potential allergens
It is in the interests of individual consumers in particular to check and evaluate the potential risks of toys – not just whether small components can get detached and swallowed or whether there is any danger of poisoning by chemical additives but also whether there is any allergenic potential. Migration and emission studies, that are carried out in the context of emission chamber measurements in the case of fragrance allergies, play a decisive role here. Since fragrances are by their nature volatile or semi-volatile organic compounds (VOC/SVOC), gas chromatography combined with mass spectrometric detection (GC/MS) [LINK] is an additional analytical method of choice to obtain a quick insight into suspicious products, which – in the final analysis – can be subjected to chamber testing in accordance with the regulations if and when they are identified as being allergenic and harmful to health.
Quality control of children’s toys is essential – there is really no alternative to it – particularly in view of the fact that products from all over the world can be ordered nowadays via the Internet and some of them are manufactured to quality standards that are nowhere near as strict as those applied in Germany. This is confirmed by an experiment carried out by Masuck et al.
The BfR scientists ordered five different scented dolls from an Internet shop. Masuck et al. explain that one of the dolls had a sweet vanilla smell, while the others were supposed to smell of popcorn, strawberry and violet – according to the promises made on the packaging. What was at any rate the case was that “the smell of all the dolls investigated differed from the typical plastic smell with its synthetic associations”. In this context, it seems to be reasonable and only sensible to ask the question here: what does plastic smell like?
Making sure that quality control is comparable
In their analysis, the scientists detected such banned substances as coumarin, cinnamyl alcohol and amyl cinnamic aldehyde. Allergenic fragrances like benzyl benzoate were in addition detected in quantities that would have made declaration on the packaging necessary. d-limonene and linalool were also found, but only when the scientists used a different extraction process, which allows the conclusion to be drawn that quality control results and the analytical procedure used need to be subjected to a critical review and should be compared with acknowledged and guaranteed (i.e. validated) processes.
The following rule of thumb can, in a nutshell, be applied by all parents, grandparents, aunts and uncles who want to give young children a treat: hands off scented toys! They need to be treated with caution and should in dubious cases be kept away from children and disposed of – at the latest when playing with the toys leads to headaches, nausea or unaccountable skin reactions. The same is true of bicycle helmets that suddenly start to give off an unpleasant smell. Although there is a very different reason for this ...
The point of bicycle helmets is to protect the heads of the people wearing them. Only undamaged helmets do what they are supposed to do in an emergency, however. It is therefore advisable to replace such helmets at regular intervals. But who willingly throws out expensive equipment on the off chance that it may be damaged?
A new process that scientists from the Fraunhofer Material Mechanics Institute (IWM) in Freiburg have developed in co-operation with the Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT) in Oberhausen is supposed to provide clarity:
If small cracks form in polymer materials, they start to smell. Larger cracks virtually stink. What are responsible for the odours are fragrant oils that are enclosed in microcapsules and are integrated in the polymer. Christof Koplin, a scientist who works at IWM, explains that damage to the helmet material, e.g. due to a crash, leads to the formation of cracks in the polymer, so that the microcapsules integrated in the polymer break open and the fragrant oil they contain escapes – with the relevant olfactory impact. This is a good time to dispose of the helmet.
Bicycle helmets are available in all shapes and sizes: there are models that can be folded up and ones with a flashing back light or an iPhone display. In future, cyclists will be able to buy helmets that start to smell as soon as they are damaged. A new process makes sure that fragrant oils escape when cracks form in plastics. The damaged helmet releases fragrances. Bottom right: the microcapsule after it has broken open.