Past Public Health Activities
The following items give more detail about the separate public health activities that led to or were completed in conjunction with the Agency for Toxic Substances and Disease Registry’s evaluation of community-wide exposures in El Dorado Hills. Activities that were merely steps towards conducting the community-wide evaluation are listed only on the Time Line web page.
Oak Ridge High School Health Consultation (January 2006)
Oak Ridge High School is located at 1120 Harvard Way in El Dorado Hills. A vein of naturally occurring asbestos (NOA) was disturbed during construction of a soccer field in 2002, and NOA was identified in rocks and soils on and around school property.
In response to a 2004 petition from an El Dorado Hills community member, ATSDR evaluated the possible health hazards of naturally occurring asbestos on the grounds of Oak Ridge High School. ATSDR released a draft health consultation for public comment in May 2005. The final health consultation, released in January 2006, included public comments received during the May 6–June 30, 2005, comment period and ATSDR’s responses. The document can be viewed here: http://www.atsdr.cdc.gov/HAC/pha/OakRidgeHS-013106/OakRidgeHighSchoolHC013106.pdf [PDF - 435 KB].
ATSDR found that current exposures to naturally occurring asbestos from campus soil at Oak Ridge High School had been minimized by the mitigations conducted by the El Dorado Union High School District and the U.S. Environmental Protection Agency (EPA). However, current or future exposures from unmitigated areas on campus or from other off-campus sources were still possible.
Nomination of Naturally Occurring Asbestos for National Toxicology Program Testing (March 2006)
In March 2006, ATSDR and EPA nominated naturally occurring asbestos and related mineral fibers for toxicological evaluation by the National Toxicology Program. The nominations were accepted for review in 2007 (http://ntp.niehs.nih.gov/go/29287). The nominations were based on widespread community exposure in certain geographic locales and insufficient dose-response information to characterize risk from exposure to noncommercial and unregulated asbestiform mineral fibers. The preliminary study recommendations for these nominations are for mineral characterization (studying the chemical and crystal structure of the materials), in vitro durability and toxicity studies (lab tests to determine how long the materials might remain in and harm lungs), and subchronic and chronic toxicity/carcinogenicity studies via inhalation (animal studies to determine short- and long-term health effects of breathing the materials). See http://ntp.niehs.nih.gov/files/Naturally_occurring_asbestos_concept_for_BSC.pdf [PDF - 152 KB] for more information. These studies will take several years to complete.
Expert Panel on Biomarkers of Asbestos Exposure (May 2006)
Concurrent with ATSDR’s Oak Ridge High School health consultation, EPA conducted activity-based sampling to evaluate personal exposures to asbestos at three schools and a community park in El Dorado Hills. This type of sampling measures the asbestos particles near the mouth and nose of a person doing a specific activity and gives the most accurate information about what people actually breathe in. The results from EPA’s sampling showed an increased potential for current exposure with dust- or soil-disturbing activity in the community.
As a result of the findings from EPA’s exposure assessment and ATSDR’s health consultation, ATSDR received many questions from the El Dorado Hills community about ways to measure actual past exposures or initial signs of disease in community members.
In response to these community concerns, ATSDR convened the Expert Panel on Biomarkers of Asbestos Exposure and Disease in May 2006. The panel suggested the most promising ways to measure NOA exposure in a population; however, most methods would require more research before they would adequately measure community exposure. The complete findings and recommendations of the panel can be found at http://www.atsdr.cdc.gov/asbestos/asbestos/biomarkers_asbestos/.