Those smears and streaks just might be black mastic, a discontinued building product that often contains asbestos.
Black mastic can be dangerous if you give a shot to remove it.
What Is Black Mastic Asbestos?
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Mastic is a general term for a jot down of glue-like adhesive.
Many modern mastics are latex or water-based and can be softened with water.
By contrast, asphaltic cutback adhesive is an older bang out of mastic made with asphalt-based cement.
The asphalt content lends mastic its black color.
Asbestos was added to the mastic for its strengthening properties, not for fireproofing.
What Does Black Mastic Asbestos Look Like?
You will only see black mastic asbestos after a floor covering has been removed.
As the name suggests, black is its predominant color.
It often has faint, embedded comb-like marks or swirls from its initial tool.
Concerns About Black Mastic Asbestos
Some, but not all, black mastics may contain asbestos.
Asbestos has been proven to cause a life-threatening condition called mesothelioma.
Some cutback adhesives contained asbestos.
It is commonly thought that asbestos was added to these compounds for fire-resistance.
No asbestos fibers in the mastic will be visible to the bare eye.
Testing the black mastic is the surest way to know if the mastic contains asbestos.
You canlay new flooring over the old flooring, provided the old flooring is flat and well-adhered.
There is no way to get rid of it safely due to its thick, gummy consistency.
It is best if the old flooring covering stays in place and is covered with new flooring.
In some cases, the products are still sold but without the asbestos content.
Mesothelioma.National Organization for Rare Disorders.
Pira, Enrico et al.Exposure to asbestos: past, present and future.Journal of thoracic disease,vol.
10, 2018, S237-S245.
