EPA memo re: wipe sampling and cancer risk at WTC,

NYC 9/11 Public Portal Document

ErT«m«hFi air levels if cleanup Is inadequate ;• Ai

Air levels might also be predicted if the cleanup is inadequate. As discussed in my December 6 7. . memorandum, the EPA determined that neither conventional nor HEPA vacuums were capable of removing significant amounts of asbestos from carpet. Only the wet-extraction HEPA vacuums removed the asbestos particles which adhere to the carpeting.’ Even the wet-extraction , HEPA vacuums did n* t remove all of die asbestos^ only about 60%

Thus, the same or similar levels of asbestos could rernam in the carpets as their were before the 'I7 ti cleanup. After cleanup, the air levels could remain as high as projected in Table 2. The dust in Y / V both of die apartments in the Ground Zero Task Force study (Table 2) was not that thick, only

li 7 fine dusting where you could still read the writing bh papers bn a table even in the high exposure i ;'<ix building.. This small amount of dust couldeasily work itswayinto thecarpet and remainJB^jV

(I have been informed that typically, in asbestos abatement, carpeting is removed and discarded

te 5 because of the inability to remove all the asbestos^ More documentation on recommendations; and this practice is requested. Information on actually testing or test methods for arfiestbs V: contaminated carpeting is also solicited. jenkins.cate@epa:gb\^i-^/*«5/ z s;;

- CALCULATING TOTAL DOSE FROM ATSDR’s^i^S^yW^O-W’<""^A. -li fe CUMULATIVE EXPOSURE f

Cumulative, or total dose, found by ATSDR to be related to health effect^-

I < The Agency for Toxic Substances and Disease Registry (A.TSDR) is part of the Centers Disease Control. It develops toxicological profiles in response to the Comprehensives - 2-e^ i? ' Environmental Re^onse, Compensation, and Liability Act (CERCLA, or Superfimd). These " i I i profiles arc subjected to extensive review by the most prestigious scientists as well as being ; reviewed and commented upon by affected industries and the public. The ATSDR found that the ; “cumulative exposure,” or total dose, was valid for predicting the pibbahiuty of suffering health effects from adiestos? There w^ no “threshold” or safelevel.^.Y-; | /Bp ' V: f;

V. A number of researchers have found that the occurrence of asbestosis arid lung cancer correlates with cumulaCvB expos ure (that Is, the product of concentration [PCM fibers/mL] multiplied by- ■ •5. rj-: years of exposure).therefore, human exposures are expressed below as PCM f-yr/mt; "

[A] number of other studies indicate that king cancer risk is linearly related to cumulative dose withoutany obvious threshold ;-' /- ■ <

In other words, it does not matter wht lei or not you got the same total dose over a short period of time at higher levels, or a long period of time at lower levels. The health effects will be the same. The ATSDR does explain that there is no absolute correlation of the total dose with health ' effects, but uses it as a valid method to evaluate health risks. -

Table 3 lists some of the “cumulative doses” found by the ATSDR to be associated with asbestos health effects. The table also gives examples of what the air asbestos levels are required for different time periods to achieve this dose. nLENo.A74983669 EXHIBIT # -7-

NYC-WTC_000140265