The quantification of asbestos fibre concentrations in air and lung tissue are an essential part of asbestos risk assessment. Such measurements can be done better in terms of microscopy technique, detection limits, practical and strategic application.
Asbestos in Air
The conventionally used phase contrast microscopy method for asbestos in air measurement in Australia (NOHSC, 2005) has a detection limit of 10,000 asbestos fibres per cubic metre of air. Australian asbestos removal contractors typically report clearance monitoring results of below detection in settings where technically measurable asbestos and residual asbestos exposure risk may exist.
The lack of quantitative asbestos in air data has the impact of not enabling asbestos removal contractors to make improvements in asbestos removal practice to minimise exposures for removal workers and subsequent building occupants.
Asbestos in Lung Tissue
The ratio of mesothelioma and lung cancer cases in asbestos workplaces was greater than 1:1 for a range of exposure scenarios (McCormack, 2012). In the case of bystander or non-occupational asbestos disease associated with residential asbestos, only mesothelioma is routinely attributed to asbestos. Lung cancer in non-occupationally exposed non-smokers for example is not being attributed to asbestos in any ratio relative to cases of mesothelioma. There is potential for cases of otherwise un-attributed lung cancer due to non-occupational and contemporary workplace exposures to asbestos. Research into the particle and fibre contents of lung tissue associated with lung cancer is warranted due to the current lack of clinical distinction of cause. Opportunities to investigate asbestos fibre in lung tissue are related to the overall question of particles and their role in causing lung cancer.
Opportunities for Microscopy
Some key drivers for seeking additional deployment of advanced microscopy technology are described in more detail along with examples of microscopy tools and solutions.