People who live near the Santa Susana Field Lab report higher rates of these illnesses

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 whose findings were announced today, though researchers cautioned the findings do not establish that contamination at the former nuclear and rocket-testing site caused the illnesses.

USC researchers surveyed 475 residents living within 15 miles of the Santa Susana Field Laboratory, a roughly 2,850-acre former nuclear research and rocket engine testing facility in southeastern Ventura County near the Los Angeles County line and the western edge of the San Fernando Valley.

The site was also the location of a partial nuclear reactor meltdown in 1959, described in the study as the worst in U.S. history. The facility has been eligible for Superfund designation since 2007 but has not been placed on the National Priorities List, leaving cleanup under state and local oversight.

Among residents living within five miles of the site, 18% reported autoimmune disorders, compared with 4% of residents living 11 to 15 miles away. Endocrine and metabolic disorders were reported by 15% of those within five miles, compared with 2% in the more distant group, according to the study.

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

The study, published in the peer-reviewed journal “Risk Analysis,” relied on self-reported diagnoses collected at a single point in time. Researchers stressed that the results show an association with proximity and do not establish that contamination from the Santa Susana site caused the reported health conditions.

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 at the site.

Researchers also examined how residents perceived the potential health risks and what actions they took to protect themselves.

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

Residents who viewed the contamination as severe and believed they were personally vulnerable were more likely to report taking precautions such as filtering tap water, leaving shoes at the door, avoiding produce grown in gardens and staying indoors on windy days, researchers found.

Higher levels of health anxiety also were associated with taking more precautions, and researchers found that residents who believed protective measures would be more expensive reported taking more of them.

The researchers said the latter finding runs counter to previous risk research and could reflect the relative affluence of the communities surrounding the laboratory. Of those surveyed, 56% reported annual household incomes of at least $100,000.

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