Salton Sea Toxic Dust Linked to Reduced Lung Growth in Children

Research from the University of California, Irvine and the University of Southern California has established a direct link between wind-blown toxic dust from the receding Salton Sea and reduced lung function in children living in Southern California’s Imperial County.

The study, published in the American Journal of Respiratory and Critical Care Medicine and JAMA Network Open, found that children exposed to higher levels of dust from the drying saline lake experienced measurable declines in respiratory health. Researchers noted that these negative effects were most pronounced among children living closest to the lake bed.

Study Methodology and Findings

Between 2019 and 2022, investigators conducted nearly 1,300 lung function assessments on nearly 500 children, all approximately 10 years of age. The research team utilized spirometry to evaluate lung size and strength by measuring the volume of air the children could exhale and the speed at which they could do so.

To determine the level of exposure, the team used data from 12 air monitors maintained by the California Air Resources Board. Dust events were defined as hours during which particulate matter concentrations exceeded regulatory thresholds. The researchers combined these air quality measurements with health questionnaires and in-person clinical examinations.

The findings indicate that higher dust exposure, measured in hours per year, was linked to lower lung function. Notably, the impact on lung growth for children living near the Salton Sea was found to be greater than the effects observed in studies of children in urban California communities located near busy roadways.

The drying of the Salton Sea is not only an environmental crisis but also a public health crisis. Our study provides concrete evidence that children in surrounding communities are facing measurable harm to their lungs as a result of increased dust exposure.

Jill Johnston, MS, PhD

Environmental Drivers of Respiratory Harm

The Salton Sea, California’s largest inland lake at over 340 square miles, was created in the early 1900s following a break in a canal carrying water from the Colorado River. While irrigation runoff from farm fields previously sustained the lake, it has been shrinking for decades due to climate change, drought, and agricultural water diversion.

Over the last 20 years, decreasing water flow has exposed 36,000 new acres of dry lake bed. As the lake recedes, wind carries dust from the exposed bed into the air. This dust is considered toxic because it contains metals and agriculture chemicals that washed into the lake over many years.

The research was funded by a federal grant from the National Institute of Environmental Health Sciences and the Southern California Environmental Health Sciences Center. The study was conducted in partnership with Comite Civico del Valle, a community-based organization in the Imperial Valley.

Future Public Health Risks

Researchers warn that air pollution in the region is likely to worsen as water sources continue to diminish. This decline is tied to ongoing Colorado River water use agreements and the potential for increased industrial activity in the area.

Specifically, proposed lithium extraction projects in the region are cited as a potential factor that could further degrade air quality and increase the health risks for local residents.

The study marks one of the first investigations to directly connect dust events from a drying saline lake to measurable declines in the respiratory health and lung development of children.