NYC-WTC_000234522

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 concentrations should be compared to outdoor concentrations. There is less information about indoor concentrations of bacteria than there is for mold, however one report (http://www.atsdr.cdc.gov/HAC/PHA/franklinfungi/ief pl.html) from the Agency for Toxic Substances and Disease Registry (ATSDR) reports that concentrations of Bacillus at 1,000 CFU/in2 and Staphylococcus at 2,400 CFU/in2 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. Therefore, 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. Chris D'Andrea 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 NYCDEPat718 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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