01/05/2021
Picture of a toy sample in the microchambers (puzzle pieces) and the 24 L desiccator chambers

Picture of a toy sample in the microchambers (puzzle pieces) and the 24 L desiccator chambers (pieces and plate)

Source: BAM

This study emerged from a cooperation between the Federal Institute for Risk Assessment (BfR) and BAM. Formaldehyde is considered as carcinogenic and is emitted from particleboards and plywood used in toy manufacturing. Emissions of formaldehyde from wooden boards and building materials have been studied at BAM for 30 years. The European standards EN 717 and the newer EN 16516 (2017) provide guidelines for such measurements by means of emission test chambers. Emission chambers are closed systems made of stainless steel or glass that themselves release or adsorb only negligible amounts of volatile compounds. Temperature, humidity, loading and air change rates can be adjusted to simulate the conditions in a real indoor environment. Market surveillance of wooden toys is frequently done by the flask method: The sample is hung in a closed flask and formaldehyde is sampled in water. However, its concordance to measurements in emission test chambers is poor. Moreover, surveillance laboratories are unable to afford laborious and expensive emission chamber testing to comply with the new amendment of the European Toy Directive. They need an alternative method that can provide reliable results. Therefore, the application of miniaturised emission test chambers was tested. Comparisons between a 1 m3 emission test chamber and 44 mL microchambers resulted in a good correlation coefficient of 0.834 for formaldehyde at steady state. The correlation between the results obtained in microchambers vs. flask showed a high variability (correlation coefficient: 0.145), thereby demonstrating the error-proneness of the flask method in comparison to methods carried out under ambient parameters. An exposure assessment was also performed for three toy puzzles: Indoor formaldehyde concentrations caused by puzzles were not negligible (up to 8 μg/m3), especially when more conservative exposure scenarios were considered (lower air change rate, more than one toy, use of toys close to the child).

Formaldehyde emissions from wooden toys: Comparison of different measurement methods and assessment of exposure
Morgane Even, Olaf Wilke, Sabine Kalus, P. Schultes, C. Hutzler, A. Luch
published in Materials, Vol. 15, issue 2, pages 262-1 - 262-16, 2021
BAM, division Materials and Air Pollutants