EPA Response to BP Spill in the Gulf of Mexico
Offshore air sampling for dispersant-related compounds
In response to the BP oil spill, EPA monitored air, water, sediment, and waste generated by the cleanup operations. Ongoing response and restoration efforts are posted to RestoreTheGulf.gov.
While emergency response data collection has ended, results continue to be available on this site. Any new data will continue to be posted to this site, and data will continue to be available here for the foreseeable future.
Much of the content of this site continues to be available for historical and information purposes, but we are no longer updating these pages on a regular basis.
On four days in May 2010, EPA deployed staff in boats to sample the air following the application of dispersant. The samples were collected to see if dispersant-related compounds could be detected in air following application. Sample locations ranged from about 30 to 60 miles offshore. Samples were analyzed for two chemicals, 2-butoxyethanol and propylene glycol, that are ingredients in the dispersant COREXIT. In addition to being found in dispersants, these compounds are common in a variety of household, cleaning, and other products.
The Coast Guard and OSHA are currently addressing occupational safety concerns at off-shore locations, including conducting occupational exposure monitoring as part of their efforts. As such, EPA does not anticipate conducting additional off-shore sampling but will continue its sampling and monitoring efforts on land.
Learn more about OSHA's response to the oil spill | View OSHA occupational exposure data
On the land along the Gulf coast, EPA is using a variety of monitoring methods and equipment to assess the quality of the air Gulf coast citizens breathe, including real-time mobile monitoring for dispersant chemicals from our Trace Atmospheric Gas Analyzer (TAGA) bus.
Learn more about EPA's TAGA bus | View air data along the Gulf Coast
Details and Results:
- May 17, 20, 21 and 22: offshore samples for 2-butoxyethanol and propylene glycol (CSV) or 2-butoxyethanol and propylene glycol (PDF) (1pg, 76K) (files posted July 19, 2010)
- On May 17, 21, and 22, EPA used boats to collect seven air samples within 30 minutes following aircraft application of dispersants. Neither of the two dispersant-related chemicals were detected in any of the samples collected following aircraft application.
- On May 20, EPA also collected air samples from a dispersant spray boat immediately after that boat sprayed dispersant. Propylene glycol was detected in the air on the dispersant spray boat while the boat was still damp with the spray from the dispersant application. An additional sample collected after that boat was washed down showed no dispersant-related chemicals. These results do not indicate concern for on-shore air quality. Occupational safety information is available on OSHA's web site.
EPA also analyzed these air samples for volatile organic compounds potentially associated with oil. These chemicals are emitted by many sources, including motor vehicles such as boats and airplanes; therefore the sampling data cannot determine where the VOCs originate. Results for benzene, ethylbenzene, toluene and xylene in these grab samples were similar to or lower than those observed in longer duration samples on shore and are below levels of health concern.
See the results of these analyses | Additional air data related to the BP spill