Dust from California's lithium-rich Salton Sea worsening child respiratory issues: Study

Wind-strewn dust from California's lithium-rich, shrinking Salton Sea may be triggering respiratory issues in children who live nearby, a new study has found.

Among the many symptoms — worse for those young people who reside closest to the saline lake — are asthma, coughing, wheezing and sleep disruptions, according to the study, published in Environmental Research.

About 24 percent of children located in this region have asthma, in comparison to the national rate of 8.4 percent for boys and 5.5 percent for girls, the authors found.

Of particular concern to the researchers was the fact that these abnormally high rates affected predominantly low-income communities of color around 150 miles southeast of Los Angeles.

“These rural environmental justice communities are facing health consequences due to local dust events,” first author Jill Johnston, an associate professor of environmental health at the University of Southern California, said in a statement.

The Salton Sea was created in 1905 by an accidental breach of the adjacent canal system, and until recently, the artificial lake was sustained predominantly by irrigation runoff from nearby farms, the authors noted.

But in the past two decades, decreasing water flow has exposed 16,000 new acres of dried-up, dusty land, which contains pollutants such as sulfate, chloride, pesticides, arsenic, lead and chromium.

“The agricultural industry in Imperial Valley has used excessive amounts of water, but one of the impacts of water conservation is the shrinking of the sea,” Johnston added.

To understand the impacts of this decline, the researchers recruited 722 school-age children from largely Latino and Hispanic communities between 2017 and 2019.

Their parents then completed a 64-question survey about their children's health histories over the previous 12 months. Some items included episodes of asthma, daily coughs for three consecutive months, congestion or excess phlegm.

At the same time, the authors harnessed data from regulatory air monitors to identify dust exposure events in which hourly concentrations exceeded 150 micrograms per cubic meter — the federal threshold for particle pollution.

Ultimately, they found that children were exposed to between 98 and 395 dust event hours annually between 2017 and 2019, with disparate effects among participants.

Every additional 100 dust storm hours per year among children living near the sea was linked to a 9.5 percentage point surge in wheeze, a 4.6 percentage point increase in bronchitis symptoms and a 6.7 percentage point rise in sleep disturbance due to wheeze, according to the study.

As the Salton Sea continues to dwindle and generate more dust, the authors emphasized a need to conduct further analyses of the public health effects and address environmental justice concerns. They also expressed concern that as lithium mining development occurs in the area, an increase in associated truck traffic would kick up more dust and exacerbate respiratory issues.

“The community has long suspected that air pollution near the sea may be impacting children’s health,” Johnston said.

“But this is the first scientific study to suggest that children living close to the receding shoreline may experience more severe direct health impacts,” she added. “Protecting public health should be integrated into the mitigation plans.”