NYC-WTC_000176130

NYC 9/11 Public Portal Document

[rNancy Jeffe^ Re; Next conference call for the indoor Taskforce COC/Benchmarks Committee PageJJ

1. The ATSDR/NYC indoor study sampled for many building related materials and minerals the only consistent finding in most residences around WTC (even after cleaning) was fiberglass in dust. In 43 of 98 samples (indoor and out) contained fiberglass. The hits ranged from 2-72% in dust by volume. The background samples were limited but no fiberglass was found in these samples. 2. The NIEHS summary we discussed yesterday indicated that UMDNJ (probably Paul Lioy) found 40-50% fiberglass in dust in three dust samples taken 1 -week post collapse. 3. Our microscopist Dr. Jim Webber, who wrote the methods used to identify asbestos by TEM and PLM, has been analyzing air/bulk dust samples from WTC provided by DEC and states he commonly sees fiberglass in the PLM analysis. The fibers tend to be thicker and longer than the asbestos fibers. 4. Dr. Eric Chatfield, a consultant to the "Ground Zero" Elected Officials Task Force sampled dust about a week after the collapse. He analyzed it for metals, dioxins and asbestos. Jim Webber has spoken with Dr. Chatfield and he has stated that he was also seeing fiberglass in these samples. As an additional note, Chatfield stated in the report that the dioxins/furans and metals levels in the bulk and wipe samples were indistinguishable from background. These were indoor dust (bulk and wipe) samples from a "high exposure location" on South end Ave. and a "low-exposure location" on Warren Street.

It would seem that if we wanted a good indicator of WTC related dust fiberglass may be the answer. It appears that the background may be between ND (approx. 2%) to 5% by volume according to Jim Webber and ATSDR. All 8 background ATSDR/NYC study samples were ND.

One potential problem is that there is no generally accepted and validated method for the analysis of fiberglass. The current method used is a variation of a method written by Jim Webber for asbestos and would be considered "semi-quantitative". This is because it requires an operators estimate of the volume of fiberglass compared to the volume of the rest if the material on the slide (a 2-dimensional view).

However, given this caveat, fiberglass appears to be a much better indicator of the presence of WTC material than many of the other material on our list. For example:

Dioxin has cost and background issues and may not have been significantly emitted from the source.

PCBs may not have been significantly emitted from the source.

PM has sampling methodology issues, there are significant sources of PM in residences and the PM standards are based on and applied to outdoor airshed-type monitoring results.

Lead, PAHs and Chromium have background issues and may not have been significantly emitted from the source.

I may request that Jim Webber analyze some bulk dust samples we took at ground zero a week after the accident for fiberglass levels.

NYC-WTC_000176132