The peer reviewed paper, Beryllium Concentrations at European Workplaces: Comparison of ‘Total’ and Inhalable Particulate Measurements was published by Koch, et al, in the Annals of Occupational Hygiene. The abstract states:
“A field study was carried out in order to derive a factor for the conversion of historic data on Be concentrations obtained by sampling according to the CFC ‘total’ particulate method into concentration values to be expected when sampling following the inhalable convention. Workplaces, selected to represent the different CuBe work processing operations that typically occur in Germany and the EU, as well as the USA, were monitored revealing a broad spectrum of prevailing Be size distributions. The data set and the statistical evaluation from this study reveal a geometric mean value of 2.88 for the factor used to convert Be concentrations from CFC sample to concentrations obtained from inhalable samplers. This fact has to be taken into account for the derivation of an OEL from Be epidemiology studies that have been based on the CFC ‘total’ particulate method, where the inhalable fraction sampling method is to be the basis for assessing compliance.”
As was stated in the paper, this research finding aligns with findings from similar studies of other metals. BeST trusts that the results of this study and the studies having the same degree of rigor and scientific support are fully integrated into the derivation of OELs for metals. Specifically, this study shows that a factor of 2.88 is appropriate for converting the epidemiology data collected in the United States to derive an OEL based on an inhalable sampling standard of measurement. Since the no adverse effect level (NOAEC) has been determined to be 0.199 μg/m3, an OEL of 0.6 μg/m3 in the EU is justified based on this conclusive study finding. You can access the details of this important research paper at: http://annhyg.oxfordjournals.org/cgi/content/full/mev009?