Asbestos dust criteria technical discussion, April 2002

NYC 9/11 Public Portal Document

Gilsenan, Michael From: Kelly McKinney [[email protected]] Sent: Wednesday, April 17, 2002 12:58 PM To: Gilsenan, Michael Cc: sbenson@oem. nyc.gov Subject: Internal Discussion on the Use of Millette's K Factors for PIC Committee Criteria

Michael,

I'm not sure if you or anyone from DEP is attending the PIC Committee sessions (formerly called the Contaminants of Concern committee) chaired by Mark Maddaloni of EPA. I'm concerned about the issue of establishing a criteria level for asbestos in dust. Below is an excerpt from our internal discussion on the matter. I can also send you the background data from the PIC Committee. What's DEP's position on this issue?

>» Kelly McKinney 04/17/02 10:35AM »> This is the major risk communication issue downtown. The public has a hard time distinguishing between the presence of asbestos in settled dust and asbestos in air. The first does not represent a health risk and the second does. Asbestos in settled dust is of course a source of airborne asbestos. However, a large body of data indicates that WTC dust and debris does not tend to aerosolize and is not a strong source of airborne particulates.

The relationship between contaminant concentrations in settled dust and airborne concentrations is unknown and this committee is attempting to establish one. They will get it wrong and it will cause problems now and in the future.

The task of this committee is to rely on established science to make decisions about real actions in the real world in real time. This is not the time to debate the merits of various hypotheses. The Millette K factor study was published almost ten years ago. If it were valid, its merits would by now be evident.

This committee should abandon an asbestos-in-settled-dust criteria. If the question is what becomes airborne, collect air sample data. If the question is what becomes airborne with activity, use aggressive measures (i.e., leaf blowers) to stir the air and then collect air data. A debate about the basic science is not appropriate and only serves to slow a process that is already much too slow.

»> Jeanine Prudhomme 04/15/02 06:57PM »> Kelly, et al:

Attached is the latest email from the PIC (potential indicator chemical) Committee (formerly known as the COC Committee) . Mark Maddaloni has proposed the use of a k factor for the asbestos criteria (and possibly other fibrous agents), which correlates asbestos in settled dust to airborne levels. Background material is attached.

Up until this point, I was operating under an assumption (incorrect) that the federal portion of the group had more knowledge of and a higher comfort level with using these k factors. This however, may not be the case. One of the items for next weeks agenda is to share information on how widely accepted or used the k factors are, so this will be discussed further.

Other options presented include the use of background asbestos in settled dust levesl as a "no action" level, and above background as an "action level" (additional cleaning, but by whom needs to be 1

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