You may have heard about how Claire’s, the makeup and jewelry store, is contesting whether some of their products contain asbestos. They claim independent testing did not reveal asbestos, while a consumer claims a test sent to an independent lab did.
We thought it would be a good time to inform those who may have been exposed to asbestos about the different methods for testing for the dangerous substance.
Types of microscopic testing
Generally, testing for asbestos involves putting various samples under a microscope to detect the presence of very small mineral fibers. It is a highly labor-intensive process.
Transmission electron microscopy (TEM) uses powerful magnification (200,000x) and chemicals to detect and differentiate asbestos from non-asbestos mineral fibers. It is the most advanced common form of detection.
Phase contract microscopy (PCM) uses an advanced microscope that can reveal microscopic fibers not readily seen through traditional microscopes. It is beneficial in that it has a fast turnaround time and is relatively inexpensive. However, it cannot differentiate from different types of fibers – it can only reveal the presence of fibers, which may or may not indicate asbestos fibers are present. It also cannot detect fibers thinner than .25 microns.
Polarized light microscopy (PLM) is most often used for building and other materials. However, it is not as reliable as other methods. PLM has less magnification than TEM or PCM, but is considered a more “economical” approach. Fully accurate results can also be prevented by the presence of tar, petroleum binding components and other materials in the sample. It is often used if there are a large number of samples to be considered.
We hope this has been informative for people who may have been exposed to asbestos.