Higher Illness Rates Reported Near Former Nuclear Site Northwest Of SFV: Study

LOS ANGELES, CA — Residents living closest to the Santa Susana Field Laboratory reported higher rates of autoimmune and endocrine or metabolic disorders than people living farther away, according to a USC study examining health concerns and risk perceptions surrounding the contaminated former nuclear and rocket-testing facility.

Researchers surveyed 475 people living within 15 miles of the roughly 2,850-acre site in southeastern Ventura County, near the Los Angeles County line and the western edge of the San Fernando Valley.

Among residents living within five miles of the laboratory, 18% reported autoimmune disorders, compared with 4% of those living 11 to 15 miles away, according to the study.

Chatsworth, Canoga Park, West Hills, Hidden Hills and Simi Valley are among the communities within five miles of the site.

Endocrine and metabolic disorders showed a similar pattern, with 15% of residents within five miles reporting such conditions compared with 2% of those living 11 to 15 miles away.

More than a third of respondents reported at least one chronic diagnosis since moving to the area.

Researchers cautioned that the findings show an association between proximity and reported illness and do not establish that contamination from the Santa Susana Field Laboratory caused the health conditions. The study relied on self-reported diagnoses collected at a single point in time.

The findings are published in the peer-reviewed journal Risk Analysis.

The Santa Susana Field Laboratory was used for rocket testing from 1949 to 2006 and nuclear reactor operations from 1953 to 1980. Radioactive and chemical contamination remains in the soil and groundwater.

The site was also the location of a partial nuclear reactor meltdown in 1959, which researchers characterized as the worst such incident in U.S. history. Although the property is eligible for Superfund cleanup, it has not been placed on the federal National Priorities List, leaving remediation under state and local oversight.

Previous investigations did not find significant increases in most cancers studied around the site, although some research identified possible associations involving bladder, blood and thyroid cancers and proximity to the facility. Researchers said uncertainty over the health effects of contamination has persisted for decades.

The USC study also examined how residents respond to perceived environmental health threats in communities that are substantially wealthier than neighborhoods typically studied near Superfund sites. Of those surveyed, 56% reported annual household incomes of at least $100,000.

"We expected to see wealthier people take more actions to protect themselves given their greater capacity to cope and affect change," lead author Jenna Blyler of USC's Wrigley Institute for Environment and Sustainability said. "Instead, fear of the contamination was what motivated protective action, rather than their perceived ability to manage the risks."

Residents who believed the contamination posed a severe threat and considered themselves personally vulnerable were more likely to report taking precautions, researchers found.

Those measures included filtering tap water, leaving shoes at the door, avoiding produce grown in home gardens and remaining indoors on windy days.

Higher levels of health anxiety also were associated with taking more precautions, according to the study. Researchers found health anxiety partly explained the relationship between existing illnesses and protective behavior.

Another finding ran counter to previous risk research: People who believed protective measures would be more expensive reported taking more of them.

Researchers said that could reflect the relative affluence of communities surrounding the laboratory or a belief that more costly precautions are more effective.

The study, "Silver spoons in toxic soups: Predictors of protective action in affluent neighborhoods near a contaminated research facility," was conducted by Blyler and USC researcher Joseph Árvai.