Normal use levels of respirable cosmetic talc: preliminary study.

Synopsis This preliminary study was undertaken to provide data from which a more comprehensive investigation to establish the safety in-use of cosmetic talcs could be designed. Methods for collecting and analysing respirable talc generated during the use of loose face powder and adult and baby dusting powders were established. Respirable particles in the air were separated from larger size particles by means of a cyclone and were collected on membrane filters. The collected dust was dissolved in acid and the solution was analysed for magnesium by atomic absorption spectroscopy. From the results the concentrations of talc in the air samples were calculated. The method was used to monitor the in-use levels of a range of cosmetic talcs. Mean concentrations in air sampled for 5 min from the start of use of Chinese grades and Italian 00000 grades of talc formulated for use as loose face powder, adult dusting powder and baby dusting powder were 0.48, 1.13 and 0.21 mg m(-3), respectively. Higher levels were found with micronised adult dusting powder (mean concentration 1.9 mg m(-3)). There was no evidence that the presence of perfume in the talc or the ambient relative humidity in the range 54-74% during use affected the levels of respirable talc, but high relative humidity <90% reduced the amount of respirable talc.