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A Random sampling examination of Crayons in Denmark Summary:At the request of the Danish Environmental Protection Agency 15 crayon products in Denmark were examined for asbestos by a random sampling. Two products were represented by two and six boxes respectively. The other products were represented by one box each. From each of the boxes three crayons were selected for analysis. After destruction of the wax by heating, the inorganic filler was analysed by X-Ray Diffraction (XRD), Polarised Light Microscopy (PLM), Phase Contrast Microscopy (PCM) and Scanning Electron Microscopy (SEM) plus Energy Dispersive Spectrometry (EDS). The result of the examination shows that six of 63 fillers contained chrysotile, tremolite or anthophyllite asbestos. No other types of asbestos were found. Some samples showed no asbestos, but cleavage fragments of tremolite and fibres of sepiolite, talc ("transitional fibres") or nemalite. Based on the number of observed asbestos fibres the concentrations of asbestos in the fillers were estimated to be equal to or less than 0.1% w/w. The observed mineral fibres are a natural pollutant of the talc and dolomite, which is used as fillers. Though no asbestos was found in a sample containing talc or dolomite, there is 95% chance that the asbestos concentration is less or equal to the concentration, which would correspond to an observation of four fibres in the sample. This applies particularly to samples that contain cleavage fragments of tremolite, anthophyllite or another amphibole mineral. That means, if a potential risk exists, that a material may contain asbestos, no observed fibres do not mean that the material is asbestos-free. The present examination shows that asbestos generally do not occurs in crayons, but that a potential risk exists, that asbestos may occurs if the crayons contain rock materials like talc or dolomite. |