Draft VOC air sampling plan for WTC community, Oct 2001

NYC 9/11 Public Portal Document

Note: If equipment setup is not completed in time for the evening sampling on Day 1, then the evening sampling will be done at the end of Day 2.

Evaluation Criteria

Results from the air samples will be compared to typical urban (if available) background ranges to determine whether there are elevated or unusual levels of chemicals. Background ranges for many of the VOCs are obtained from two databases. The United States Environmental Protection Agency’s Volatile Organic Compounds Database Update (EPA Database, March 1988) is a compilation of indoor and outdoor data from studies of homes and offices across the United States. The New York State Department of Health Database (NYSDOH Database, August 1997) is a summary of indoor and outdoor air sample results in control homes collected and analyzed by the NYSDOH from 1989 through 1996. These studies include sample locations where there were no known spills or unusual sources of VOCs. If available, the results will also be compared to data from EPA’s BASE database (VOCs, aldehydes). Background data from the NYC asthma study (2000-2001) is available for aldehydes (rooftop lower Manhattan) and acidity. Also, data from the NYC asthma study is available for the gases, HONO, HNO3, HCL, SO2 and NH3 from July 1999 to June 2000. Values for these constituents are also in the scientific literature.

All results will include an evaluation of how the results compare between the upwind, downwind and in the smoke samples. The upwind samples define background for the specific analyte on that day. The sample

Also, the results will be compared to acute, intermediate and/or chronic public health assessment comparison values for inhalation exposure. The choice of comparison value will depend on what the sampling site represents in the way of potentially exposed populations, environmental conditions and variability of the results.

Recommendations for the general public will be suggested based on the sampling results, public health comparison values, health endpoint, etc. Comparison values that are exceeded will be evaluated on a case-by-case basis with consideration being given to the sampling time, how representative is the sample, typical background levels, the strength of available toxicological information for the contaminant, and the estimated margins of exposure relative to exposure levels known to cause adverse health effects in animals or humans.

Sampling for semi-volatiles may provide data that is potentially useful in cohort studies including at least one proposed study of asthmatics. The purpose of this sampling is to see if there is a contaminant in the WTC fire smoke that could be used to identify a biomarker. The data will be evaluated by comparing downwind samples versus samples from upwind versus smoke leaving the nibble. The idea is to locate a semi-volatile compound that is unique or significantly increased in concentration compared to background. If such a compound is found, we will evaluate the significance of that compound by evaluating the finding to that in the published literature. If there is a particular semi-volatile that is a signature of the fire, this chemical or its metabolites may be something that can be measured in blood and or urine to indicate exposure and be useful in proposed epidemiologic studies.

The attached appendices in addition to showing the specific analytes provide more information on the specific to evaluate the resulting data.

NYC-WTC_000153216