Is the quantification of Asbestos in Soils still a lottery?

It would seem so according to the latest Asbestos in Soils Scheme (AISS) published report for Round 13 June 2017.  Whilst the UK laboratories taking part in the scheme, run by the HSL, all passed the identification test, the quantification element showed up considerable variability in the accuracy of results submitted by different laboratories in attempting to quantify the 0.05% of anthophyllite asbestos (loose fibre) by weight of the dried soil sample. Thirty-one UK laboratories took part in Round 13, 19 from the EU and 3 from the rest of the world but only 40 submitted for the quantification part of the test. The median of quantitative results submitted was 0.03625%, and there was considerable scatter of data with 35% of laboratories submitting what the Report concluded were questionable results and 7.5 % of laboratories submitting what the report concluded as unsatisfactory.

The report is anonymous and Round 13, for whatever reason, did give much worse results than Round 12 where 87.5% of the laboratories submitted results with a satisfactory accuracy. Nevertheless, as Land Quality consultants are often making decisions with respect to the need for costly remediation schemes based largely on the result of laboratory analysis this is somewhat concerning. Certainly, it has been rumoured that remediation contractors have come to know which laboratories quote “find asbestos” and which ones don’t.  Perhaps in future those procuring laboratory asbestos in soils should not only be checking out methodologies, limits of quantification and detection, UKAS accreditation but also the results of their AISS proficiency testing.