NYC-WTC_000160448

NYC 9/11 Public Portal Document

Bacteria

The interpretation of the bacteria results has the same limitations as discussed above for mold, namely, that indoor-eoncentrations should be compared to outdoor concentrations. There is less information about indoor concentrations of bacteria than there is for mold As with mold, there are no standards to-for comparisone-results to.:? Hhowever, one report (http://www.atsdr.cdc.gov/HAC/PHA/franklinfiingi/ief p 1 .html) from the Agency for Toxic Substances and Disease Registry (ATSDR) reports states that concentrations of Bacillus at 1,000 CFU/ifr2 and Staphylococcus at 2,400 CFU/in/2 are low and most likely are a normal part of the bacterial load. The concentrations reported from 114 Liberty are much lower than these values and should be considered background levels. In addition, the dominant species found was Staphylococcus, a common human associated bacterium. Thereforej even though there was not an appropriate outdoor sample collected for comparison, it can be concluded that the bacterial concentrations reported from the one indoor sample that was collected-are typical of an indoor environment.

If you have any questions related to health-based benchmarks, please contact Dr. Mark Maddaloni of EPA at (212) 637-3590. If you have any questions related to mold or bacteria, please contact Mr. Christophe D'AndreaXhH of the New York City Department of Health and Mental Hygiene at (212) 788-4290.

If you require any additional information, please contact Michael Gilsenan of NYCDEP at 718 595-4418.

Sincerely,

Robert C. Avaltroni Kathleen Callahan Deputy Commissioner Assistant Regional Administrator Bureau of Environmental Compliance Response and Recovery Operations NYCDEP USEPA

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