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Vermiculite in Homes

Vermiculite in attic; Image from EPA

In May 2003, EPA released information indicating that vermiculite contaminated with traces, less than 1% asbestos, is of significant concern.  In this release (“National Consumer Awareness Campaign Launched on Vermiculite Insulation Used in Some Attics”), the EPA states that “… home testing vermiculite in attics is not currently practical. Therefore it is best to assume that the material may contain asbestos and take the appropriate precautions…” 



Analytical Concerns Reported

  1. Two rare forms of asbestos have been reported in Zonolite vermiculite from Libby Montana which are not among the 6 asbestos minerals regulated by federal and state agencies and are not routinely included in lab tests, other than a research method which is described below.
  2. Asbestos is not uniformly distributed in vermiculite so that a negative sample result may not be reliable.
  3. There is evidence of hazardous airborne asbestos concentrations associated with disturbance of vermiculite with amounts of asbestos less than the current regulated (1%) concentration.

Justification for Testing Vermiculite

Typical vermiculite insulation; Image from EPA

Although a result of none detected or < 1 % by PLM does not assure that the material is “safe”, the primary purpose would be to see if the material is regulated under the present EPA, OSHA, DEP and DPH regulations, i.e. > 1% by PLM. Historically, we have found up to 30% asbestos in environmental vermiculite samples by this method. If the material exceeds the 1% level, then specific requirements are triggered if the owner elects to remove or otherwise abate the material.

Materials with <1% asbestos are not defined as asbestos containing materials in State and EPA regulations. However, OSHA regulations require proper procedures be used to prevent exposure to workers performing the related disturbance. This includes training and protection for employees who may be exposed above the OSHA PEL (permissible exposure limit).

As with any samples taken by an unlicensed person (not a CT DPH licensed asbestos inspector), the samples are for informational purposes only and will not be recognized by CT-DPH.

Supplementary Information:

  • EPA reports 2-15% tremolite asbestos in Libby, Montana vermiculite ore tailings using the PLM method. 
  • EPA has also had many other vermiculite samples tested using both TEM and PLM. The concentrations found in EPA studies of the actual vermiculite product as sold is much lower than the Libby mine tailings, ranging from none detected to about 2%.  Most samples had below 1%. Sometimes the TEM picks up these traces and PLM does not.  Sometimes PLM detects asbestos and TEM does not. Part of the problem is that the material is not homogeneous considering the small sample size used.
  • Asbestos has also been added to vermiculite in the range of 10-30% as part of a manufacturing process. These materials are unquestionably regulated and the asbestos is readily detected by routine PLM analysis.

Zonolite Attic Insulation Trust

We received this link from the State of CT DPH:  http://www.zonoliteatticinsulation.com/

W.R. Grace offers payment for part of the cost of past or future removal of Zonolite Attic Insulation. This only applies to the Zonolite brand of insulation   We have read the conditions and they seem reasonable. However, we can’t guarantee your results from any endeavors to obtain trust money.

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