asbestos content and risk

2 of 2 people found this post helpful

Post Reply | Watch this Post

Two percent asbestos content is not unusual for acoustic ceilings and indicates a contaminate level for ceilings using mica minerals, not asbestos fiber. Mica is a silica mineral that is closely related to asbestos but where the crystals form in flat plates rather than rolled fibers. Asbestos in this matrix is very difficult to quantify due to interference in the test method. Mica is so closely related to chrysotile chemically, that both appear as the same color in polarized light microscopy using stain techniques; the sole difference is the form of the mineral; e.g. fiber diameter and length. In other words, almost any sample of mica will also indicate low levels (2 parts in 100) of asbestos.

Although no one should unnecessarily expose themselves to asbestos fiber, your exposure was to a form of chrysotile asbestos that has the lowest potential for long-term effects, indeed, there is some question whether the serpentine forms like chrysotile are associated with any measurable increase in risk.

I have worked with commercial acoustic ceilings and fireproofing ranging from 15 to 25% asbestos; and have even seen 15% to 20% amosite in commercial ceiling tile. (This is a highly hazardous asbestos form and was illegally removed by temporary workers with no protection under the direction of a developer who actually had a professional survey done beforehand, but chose to remove it anyway). I have seen asbestos pipe insulations containing 80% asbestos removed by a handyman in a childrens clothing store in an upscale community. I was an EPA regulator at the time.

One lesson you can take from this is that asbestos releases may occur near you from time to time that you have no awareness of. Asbestos exposure studies have been conducted (postmortum) that have yet to find the person who has zero exposure. Nearly everyone has some level of exposure. I live in an area where serpentine rock has been shown to release chrysotile and tremolite forms of asbestos during construction. The local school is currently undergoing millions in abatement work to cover contaminated athletic fields with clean materials at a cost of million$.
So zero risk may be unattainable.

The biggest factor in risk is an apparent synergistic effect caused by both chronic (occupational levels)asbestos exposures and smoking, with smoking being the higher component of risk.

The remainder of your ceilings could be removed using wet methods to suppress dust. Use a fitted respirator using HEPA cartridges. Dispose of materials in marked containers. Wash down all ceilings and walls using soapy water, and when dry, repaint to encapsulate. If any carpet was in the area and not completely covered or sealed, replace it.

Legally, homeowners are not regulated by either OSHA or EPA for removal done in residences with four or fewer units. Depending on your location, the disposal may be regulated by local waste authorities in order to protect workers that may be exposed to improperly contained materials. A professional abatement company is highly regulated in the same work due to OSHA requrements for worker protection and licensing restrictions by state agencies. At this stage, you would not incrementally benefit by incurring this cost, but I would consider it for future work on the material in other room.

I hope this helps, and let me know if you need more information.