The Agency for Toxic Substances and Disease Registry (ATSDR), a public health agency of the U.S. Department of Health and Human Services, is releasing today for public comment a focused public health assessment (PHA) on the air pathway for possible contaminants from the U.S. Navy's bombing range site on the island of Vieques, Puerto Rico.

ATSDR conducts PHAs to report information about hazardous substances in the environment and evaluate whether exposure to those substances in the past, present or future could harm people in the area.

This PHA on air was conducted to determine if exposure to air contaminants potentially released from Navy property on Vieques could have adverse effects on a person's health.

ATSDR found that the residents of Vieques have been exposed to contaminants released during the Navy's military training exercises, but these exposures are much lower than levels known to be associated with adverse health effects. As a result, ATSDR finds that the air exposure pathway on Vieques presents no apparent public health hazard.

To characterize the air quality at Vieques, ATSDR identified and obtained a wide range of relevant data. Specifically, ATSDR initiated an air sampling study during a recent military training exercise and reviewed relevant studies prepared by the following parties: the Puerto Rico Environmental Quality Board (PREQB), several academic and independent researchers from universities and private organizations in Puerto Rico, the U.S. Environmental Protection Agency, and the Navy and its contractors.

In May 1999, an island resident asked (petitioned) ATSDR to evaluate whether any health problems of Vieques residents might be associated with potential releases of hazardous substances from military training activities on the island. ATSDR responded by conducting a series of focused public health assessments, on groundwater/drinking water, soil, fish and shellfish, and air pathways. After completing its evaluations, ATSDR will assess the public health implications of the cumulative or overall exposures from the pathways the agency has considered.

For the air exposure pathway, ATSDR also concludes the following:

• Air samples have shown that levels of particulate matter are much lower than health-based air quality standards. Thus, wind-blown dust from the live impact area (LIA) is not a health hazard.

• Additional sampling data are needed to characterize potential exposures during the military training exercises that use practice bombs, which release various contaminants to the air. The available sampling data indicate that ambient air concentrations of particulate matter, metals and explosives do not reach levels that present a public health hazard. Nevertheless, part of ATSDR's recommendations call for a continuation of routine air sampling of particulate matter and metals.

• Most of the contaminants released to the air during past military training exercises involving live bombs were dispersed to extremely low concentrations over the 7.9 miles that separate the center of the LIA from the nearest residential areas of Vieques. ATSDR's best estimates of ambient air concentrations suggest that past exposures during the live bombing exercises were at levels below those associated with adverse health effects. Because live bombing has not occurred in several years, and there were no data to permit ATSDR to evaluate actual conditions associated with live bombing, TthisThis conclusion is based entirely on modeling results and therefore involves some uncertainty., although ATSDR, however, believes its approach to evaluating the live bombing exercises provides a reasonable account of past exposures.

• Open burning and detonation operations to treat unused munitions and unexploded ordnance have released contaminants to the air, but these operations account for a small fraction (<10%) of the high explosives that were previously detonated during military training exercises using live bombs. However, ATSDR's modeling analysis indicates these emissions do not cause levels of pollution that could present a public health hazard in Vieques residential areas.

• Residents of Vieques are not exposed to levels of environmental contamination that could present a public health hazard, whether chemical or radiological, as a result of the Navy's limited past use of depleted uranium penetrators during military training exercises. Further, no adverse health effects are expected to result from the Navy's usage of chaff, because this material disperses considerably between the time it is released (several thousand feet above sea level) and the time it settles to the ground. Ambient air sampling during future military training exercises can provide additional insights into potential exposures associated with chaff.

ATSDR recommends the following actions be taken:

• To provide more information on long-term exposures to air contaminants, ATSDR recommends that PREQB continue its routine air sampling of particulate matter and metals in Esperanza and Isabel Segunda.

• To provide more information on short-term exposures to air contaminants during military training exercises involving practice bombs, ATSDR recommends that PREQB continue to collect air samples for particulate matter and metals daily during these exercises. ATSDR recommends that the Navy coordinate similar sampling on its property, such that researchers can identify the sources of air pollution that contribute most significantly to the measured levels of contamination. ATSDR recommends that such a sampling study take place during a typical exercise involving practice bombs.

• No live bombing has occurred on Vieques since 1999.ATSDR has no knowledge whether live bombing will ever resume at Vieques If it doesthe Navy ever were to resume live bombing exercises, ATSDR recommends that PREQB collect daily samples in Esperanza and Isabel Segunda of particulate matter, metals, volatile organic compounds, and semi-volatile organic compounds. Moreover, ATSDR recommends that the Navy coordinate similar sampling on its property such that researchers can identify sources that most likely contribute to air concentrations of contaminants that are detected.

• ATSDR recommends that any residents using rainfall collection systems for a drinking water supply read the documents that ATSDR has placed in the records repositories regarding good sanitation practices for harvesting rain water. These good sanitation practices will help ensure that water obtained from these systems is safe to drink and relatively free of contamination from all local sources.

• ATSDR plans to review cancer registry information and data gathered by the Puerto Rico Department of Health (PRDOH). This review will consider the data documented in ATSDR's PHAs and will evaluate the general health status of the communities on Vieques. ATSDR's review will follow the official release of PRDOH's review of the cancer registries, but it is not known when thatisthis will occur.

• ATSDR will periodically review air sampling data that PREQB and other parties collect at Vieques, as these data become available. In particular, ATSDR will review ambient air monitoring data that PREQB has collected on metals, once those become available.

The draft health assessment will be available for public review and comment on or about Dec. 18, 2002, at the following records repositories:

The public comment period will end February 24, 2003. ATSDR welcomes comments from the public. Send written comments to the following address:

Chief, Programs, Evaluation, Records and Information Services Branch
Division of Health Assessment and Consultation
ATSDR Mailstop E-32
1600 Clifton Road NE
Atlanta, GA 30333

Comments received during the public comment period will be logged into the administrative record of the health consultation. Public comments and ATSDR's responses will be included in an appendix to the final health consultation when it is released. Although the names of those who submit comments will not be included in the final health consultation, the names are subject to release in response to requests made under the U.S. Freedom of Information Act.

Community members who would like more information about the PHA may contact Jeff Kellam, health assessor, in Atlanta at 1-888-422-8737, ext. 0373; or Maria Teran-MacIver, community involvement specialist, in Atlanta at 1-888-422-8737, ext. 1754. Callers should mention the Vieques air pathway PHA. Regional Representative Arthur Block may also be contacted in New York at 212-637-4307.