Along the shores of the shrinking Salton Sea, desert winds regularly kick up dust and send it drifting through nearby neighborhoods. New research indicates that living there may affect kids’ lungs.
Scientists from the University of Southern California tested the lung capacity of 369 children between the ages of 10 and 12 for about two years and found that those who live less than 6.8 miles from the Salton Sea have diminished lung development compared with kids farther away.
The slower pulmonary development in these children was similar to the development of those who live very close to freeways.
“Basically, their overall lung capacity isn’t developing at the same rate as kids that live further away,” said Shohreh Farzan, a co-author of the study and associate professor at the USC Keck School of Medicine. “We’re seeing the impacts of dust events and proximity to the sea as being detrimental to children’s lung development.”
When lung growth is hindered in adolescence, “that can lead to increased risk for respiratory, cardiovascular, and metabolic diseases later in life,” said Fangqi Guo, the study’s lead author.
The Salton Sea is California’s largest lake, covering about 300 square miles in Imperial and Riverside counties. It’s fed as Colorado River water drains off farm fields in the Imperial Valley.
The saline lake has been shrinking rapidly since the early 2000s, when the Imperial Irrigation District began selling some of its Colorado River water to growing urban areas under an agreement with agencies in San Diego County and the Coachella Valley.
The lake has gone down 14.5 feet since 2003, exposing more than 41,000 acres of lakebed. Researchers say years of agricultural chemicals and metals washing into the lake have made the dust toxic.
In low-income communities near the lake, children suffer from asthma at high rates. Researchers have previously found that about 1 in 5 children in the area have asthma, nearly triple the national average.
Other research has shown that dust collected near the Salton Sea triggers lung inflammation in mice.
For the latest study, published in JAMA Network Open, the USC researchers worked with the community group Comité Civico del Valle to recruit children to participate.
They measured how much air the children can push out after a deep breath.
They examined levels of fine particles in the air, as well as times when dust levels spike, often triggered by winds.
Dust around the Salton Sea has been recognized as a health problem for years.
To help control it and provide habitat for fish and birds, California agencies have been building berms and sending water flowing into man-made ponds along the shore, creating new wetlands. They’ve also been placing thousands of bales of straw on the exposed lakebed to block windblown dust.
“I think these efforts are not moving quickly enough,” Farzan said. “We need to have a renewed focus on making sure that we’re protecting children’s health.”
The dust doesn’t come only from the Salton Sea playa. It comes from the surrounding landscape, including farm fields, livestock operations, diesel exhaust and unpaved roads.
In a report last year, researchers with the Pacific Institute cited estimates that dust from the Salton Sea accounts for less than 1% of small particle pollution in the region.
Even though it may be a small percentage, Farzan said, “our results are clearly showing that there is something about proximity to the sea that is impactful for children’s health.”
The researchers did not differentiate between sources of dust in their latest study.
“It is possible that that small fraction may be more toxic, may contain different contaminants,” she said. “That’s something that we’re still really interested in learning more about.”
The dust could worsen if looming water cutbacks on the Colorado River accelerate the decline of the Salton Sea. The river flow has declined dramatically over the last quarter-century during a megadrought worsened by climate change.
There are similar issues at other drying lakes around the world, from Utah’s Great Salt Lake to the Aral Sea in Central Asia, Farzan noted, and this will require bigger efforts to contend with dust and its effects on people’s health.
