NYC-WTC_000204901

NYC 9/11 Public Portal Document

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PCB Air Monitoring Data Summary for Lower Manhattan WTC Sampling

Totals (for sampling through ^;j 01/15/02, in ng/m3) Total Samples - All Sites 261 I Samples Above Screening 0 y Level % Above 0.00% Samples Below 261 Maximum Value (10/02/01); 153 Minumum Value: ND Screening Level*; 730 o Average All 3.79 § Polychlorinated biphenyls, or "PCBs", have been used as coolants and lubricants in transformers, capacitors, and other electrical equipment because they are good insulators. The manufacture of PCBs was °A-. stopped in the U.S. in 1977 because of evidence they build up 0% in the environment and can cause harmful health problems. Products made before 1977 that may contain PCBs include old fluorescent lighting fixtures, electrical devices containing PCB capacitors, and old KIWI?®® BSamples Above Screening Level hydraulic oils.

To date, all measurements of I® □ Semples Below airborne PCBs at sites surrounding the WTC work zone have been below ERA'S screening level. The ERA screening level is set well below exposure levels shown to cause cancer in animals, as well as 100% those associated with any other health effects. The screening level is based on continuous exposure for a year to an average concentration of 730 nanograms per cubic meter.** Because measured PCB levels to date have been significantly lower, we do not expect increased risks of health problems as a result of PCBs from the WTC site.

The ERA screening level is set well below exposure levels shown to cause cancer in animals, as well as those associated with any other health effects.

**The unit is ng/m3 or the mass of PCBs in nanograms (a billionth of a gram) in a cubic meter of air.

CITY_21MC100_008980701

NYC-WTC_000204901