NYC-WTC_000176130

NYC 9/11 Public Portal Document

Next conference call for the indoor TasIdorcg QQC/Benchmarks Committee ' PageT]]

From: "Robert L. Chinery" <[email protected]> To: <[email protected]>, <[email protected]>, <svr1 @cdc.gov>, <[email protected]>, <[email protected]>, <[email protected]>, <[email protected]>, <[email protected]>, <[email protected]>, <njeffery @ health.nyc.gov> Date: 3/15/02 4:18PM Subject: Re: Next conference call for the indoor Taskforce COC/Benchmarks Committee

Mark and I had a discussion this morning that is worth revisiting with the COC group. There were two issues; one is focused on the potential use of "surrogates" and the other on criteria for selection of COC's. This email is for discussion purposes for the Monday call.

Surrogates

With regard to surrogates, the question is: Can a chemical or fiber indicate the presence of WTC related dust? If a surrogate exists can it be used to identify those apartments that are contaminated with WTC dust? Also, can a surrogate be used to identify when apartments are appropriately cleaned by only sampling for the surrogate versus all the individual chemicals that may be present? Since the purpose of post-cleaning sampling is to determine the effectiveness of clean-up, perhaps only the surrogate needs to be monitored.

Two potential surrogates exist, pH and fibrous glass (see the email below on the fibrous glass as a surrogate). These materials are related to building construction. The pulverized dust that was spread around the city after the collapse appears to have a high pH (due to cement and other bldg. materials) and significant levels of fiberglass (see below). PH has the potential advantage of being measured in the field and fiberglass is a simple and inexpensive PLM analysis. Background levels would be used to determine the clean-up guidelines for these surrogates.

COC Selection

There is a concern that we not be viewed as being arbitrary in selecting/de-selecting materials for the COC list. We need to decide on objective, scientifically defensible criteria to either add or remove materials from the list. Once the criteria are derived they are applied to determine the COC's. Also, a thorough explanation as to why the chosen material meets the criteria would be developed. This will allow the scientific peer review panel (that the Task Force is setting up) and the public to judge the justification and selection of COCs. Also the public needs to be assured that we are trying to address their concerns regarding irritation and respiratory effects of dust in residences with the COC list.

As a "strawman" I would suggest the following:

1. The main criteria for selection of COC's is the public's need to feel assured that indoor spaces do not contain WTC dust which may cause respiratory irritation or other respiratory effects. Additionally the public is concerned about long-term health effects (which assumes a long-term exposure to the dust in residences). The available environmental data from the city and toxicity/existing guidelines should be used to make these decisions (the EPA air dataset is the most comprehensive and probably should be the priority dataset).

NYC-WTC_000176130