4000bce - 399
400 - 1399
1400 - 1499
1500 - 1599
1600 - 1699
1700 - 1799
1800 - 1899
1900 - 1999
The U.S. Environmental Protection Agency (EPA) and other federal, state and local agencies have collected extensive environmental monitoring data from the World Trade Center site and nearby areas in Manhattan, Brooklyn and New Jersey. Since September 11, EPA has taken samples of the air, dust, water, river sediments and drinking water and analyzed them for the presence of pollutants that might pose a health risk to response workers at the World Trade Center site and the public. The samples are evaluated against a variety of benchmarks, standards and guidelines established to protect public health under various conditions. EPA is collecting data from more than 20 fixed air monitors in and around ground zero and additional monitors in the Bronx, Brooklyn, Queens and Staten Island. The Agency is also using portable sampling equipment to collect data from a range of locations.
Air: Fixed Monitors in New York:
Asbestos - EPA analyzed 123 samples taken in and around ground zero from November 16 through 19. In addition, EPA sampled for asbestos at three additional lower Manhattan locations on October 17, 18 and 22 and November 14 and 15, for a total of 137 samples. All samples showed results less than 70 structures per square millimeter, which is the Asbestos Hazard Emergency Response Act (AHERA) standard for allowing children to re-enter school buildings after asbestos removal activities. This brings the total number of air samples collected and analyzed for lower Manhattan to 2,408, with 28 samples above the standard (27 were collected prior to September 30 and one was collected on October 9).
Staten Island Landfill:
Air (Asbestos) - Sixteen samples were collected on November 18. All but one of these samples were below the school re-entry standard. One sample, taken at the Mess "Tent" Location #15, was above the school reentry standard.
Air (Particulates) - EPA used portable monitors to collect samples of particulates on November 19 at the Staten Island Landfill. There were no significant readings.
Particulate Monitoring - EPA used portable monitors to collect samples from November 15 through November 19 in the following locations: L (north east side of Stuyvesant High School); N (south side of Pier 25); and R (north west side of Stuyvesant High School). Particulate levels at all locations were below the OSHA time-weighted permissible exposure limit.
Dioxin - Ten samples were collected on October 26 and analyzed for dioxin/furans. Two of the samples (Location B - Church & Dey and Location 3A - between World Trade Center buildings 4 & 5) showed results above the level at which EPA would take some type of action to reduce people's exposure. This action guideline is based on a 30-year exposure. However, none of the samples were above the EPA action guideline adjusted to a one-year exposure. These levels do not pose a short-term health affect but should be monitored if they persist for a long period of time.
PM 2.5 - Monitoring for fine particulate matter (particles less than 2.5 micrometers in diameter) was conducted on November 18 and 19 at Pace University, Borough of Manhattan Community College, and the Coast Guard building in Battery Park. All 24-hour averages were below the National Ambient Air Quality Standard (NAAQS) of 65 ug/m3 for all stations. These results were also less than 40 ug/m3, a level on the EPA Air Quality Index indicating that air quality is unhealthy for sensitive populations (e.g., those with respiratory illnesses).
Silicates - Thirty samples were collected on October 30 and November 6 and 8 (ten samples collected on each day) and analyzed for silicates. Silicates were not detected in any samples collected on Oct. 30 and Nov. 6. Samples collected on Nov. 8 were non-detect or were detected at levels below the NIOSH Recommended Exposure Limit (REL) time-weighted average of 0.05 mg/m3.
Metals - Ten samples were collected on November 2. Analysis for all metals were either non-detect or below applicable standards, guidelines and permissible levels established by EPA and OSHA. Final analysis of these samples for chromium showed that chromium is not present.
U.S. Government Website