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313 N. Figueroa Street, Room 806  |  Los Angeles, CA 90012  |  (213) 240-8144  |

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For Immediate Release:

March 19, 2016

Public Health Conferring with US EPA and Professor Jerrett, of UCLA Fielding School of Public Health, on Porter Ranch Study

LOS ANGELES – The Los Angeles County Department of Public Health (Public Health) is conferring with Michael Jerrett, professor and chair of environmental health sciences at the UCLA Fielding School of Public Health (FSPH), and the US Environmental Protection Agency Indoor Air Quality Group (EPA) as Public Health develops a work plan and protocol for indoor environmental testing of homes in the Porter Ranch community. The purpose of the indoor testing is to assess the presence of chemicals associated with the natural gas leak at the Aliso Canyon Storage Facility that was detected October 23, 2015 and was confirmed sealed on February 18, 2016 by the California Division of Oil, Gas and Geothermal Resources.

Professor Jerrett has been independently collecting outdoor air quality samples throughout the Porter Ranch community. Preliminary analysis showed higher and more variable concentrations of particulate matter in the outdoor air at locations close to the leak site compared to those farther away. As a continuation of Professor Jerrett’s independent study, an indoor dust swab sampling was completed in seven homes. Benzene and hexane were found in two of the homes. Benzene and hexane, at certain levels, have known toxic effects on humans, but it is unknown whether the levels found are high enough to be of health concern. Professor Jerrett is sharing these findings with the community and will continue to conduct independent scientific analyses.

Benzene is a chemical that is a natural part of crude oil, motor vehicle exhaust, as well as cigarette smoke. Hexane is a chemical made from crude oil.

Particulate matter is made up of particles (tiny pieces) of solids or liquids that are in the air. These particles may include: dust, dirt, soot, smoke or drops of liquid. Some particles are big enough to see while others are so small that you cannot see them in the air. These particulates could irritate the skin, eyes, nose, throat, respiratory, and cardiovascular systems and potentially cause a number of other effects in humans.

Public Health is conferring with the US EPA and Professor Jerrett as it launches its indoor environmental testing effort, scheduled to begin late next week. Public Health is committed to applying the best science available to assist the community and mitigate potential public health impacts.

The Department of Public Health is committed to protecting and improving the health of the nearly 10 million residents of Los Angeles County. Through a variety of programs, community partnerships and services, Public Health oversees environmental health, disease control, and community and family health. Public Health comprises nearly 4,000 employees and has an annual budget exceeding $900 million. To learn more about the LA County Department of Public Health and the work they do, visit, and follow Public Health on social media at,, and