New dust sources from a shrinking Salton Sea have negative ecological and health impacts

August 3, 2017, University of California - Riverside
The Salton Sea from space. Credit: NASA

Scientists at the University of California, Riverside investigating the composition of particulate matter (PM) and its sources at the Salton Sea have found that this shrinking lake in Southern California is exposing large areas of dry lakebed, called playa, that are acting as new dust sources with the potential to impact human health.

"Playas have a high potential to act as dust sources because playa surfaces often lack vegetation," said Roya Bahreini, an associate professor of environmental sciences, who led the research project. "Dust emissions from playas increase airborne PM mass, which has been linked to cardiovascular disease, respiratory disease, and mortality."

Study results appeared recently in Environmental Science and Technology.

Bahreini's team set out to test whether emissions from playas change the composition of PM10 (particulate matter with diameters up to 10 microns) near the Salton Sea. The team assessed the composition of playa soils (recently submerged underneath the Salton Sea), desert soils (located farther from the sea), and PM10 collected during August 2015 and February 2016.

They found that dust sources contributed to about 45 percent of PM10 at the Salton Sea during the sampling period while playa emissions contributed to about 10 percent. Further, they found that playa emissions significantly increased the of PM10.

"Increase in the sodium content of PM10 can affect the ecosystem when the sodium-rich particles deposit downwind and change the natural balance for soils and agricultural lands or when these particles form clouds," Bahreini said. "Currently, the primary concern for PM emissions from playa is the contribution to total concentration of PM10, which regardless of composition, is an irritant and can have negative respiratory effects."

Her team also found that playa soils and PM10 are significantly enriched in selenium relative to desert soils.

Bahreini explained that selenium can be a driver of aquatic and avian toxicity. "Additionally, higher selenium enrichments in PM10 during summertime suggest that selenium volatilization from the playa may become an important factor controlling the selenium budget in the area as more playa gets exposed," she said.

Alexander L. Frie, a graduate student in environmental sciences and the first author of the research paper, at the sampling site. Credit: Bahreini lab, UC Riverside.

Alexander L. Frie, a graduate student in environmental sciences and the first author of the research paper, urges that the Salton Sea be paid close attention since, although it is widely considered a large ecological disaster, with no serious monitoring and remediation efforts the sea may also create a crisis for the surrounding area.

"Although our results indicate playa emission may not be especially toxic when compared to other dust particles, increased emissions from a shrinking sea will reduce the quality of life of the residents within the Imperial Valley and other downwind regions," he said.

Samantha C. Ying, an assistant professor of environmental sciences and a coauthor on the paper, stresses that monitoring the increase in dust sources over time is necessary to quantify its contribution to local health problems.

"Our study shows that the shrinking Salton Sea is contributing to dust sources in the region," she said. "Even considering just the small area of playa that is exposed now, the contributions are significant."

Another concern the researchers point out is that water that is currently diverted from the Colorado River and directed into the Salton Sea is scheduled to end before 2018. The resultant decrease of inflow into the sea will likely cause a decline in water level, exposing more playa, and therefore emitting more .

"With more playa being exposed, we expect total PM10 concentrations to increase and human exposure to these particles in downwind areas will also increase," Bahreini said. "Therefore implementing any project, for example, creating shallow water pools over the playa, that limits formation of salt crusts on the playa will be valuable."

Bahreini, Frie and Ying were joined in the study by Justin H. Dingle, a graduate student in Bahreini's lab.

Explore further: Urban air pollution – what are the main sources across the world?

More information: Alexander L. Frie et al. The Effect of a Receding Saline Lake (The Salton Sea) on Airborne Particulate Matter Composition, Environmental Science & Technology (2017). DOI: 10.1021/acs.est.7b01773

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Shootist
5 / 5 (1) Aug 03, 2017
The Salton Sea is artificial, destroyed "sacred" "pristine" "environments" as it appeared. It's removal repairs the "evil" damage caused by man's depredations.

GAD!
Osiris1
1 / 5 (1) Aug 03, 2017
Like it or not, places of natural impouindments in the past like 'Salton Sea' ARE the wave of a global warming future accompanied by 'mega-droughts'. These areas and more will end up being PUMPED full of water from the ocean for large scale de-salinization efforts which will need forebays for input and afterbays for output ready to ship to starving water systems up and down California. We Californians are on our own. We have helped neighboring beggar states to the east all governed by corrupt rapacious republicans voted in by ignoramuses or the barfly kind for decades, but when WE need help, we get folks like 'script-boy' Shkrelli and his med-kite scheme, or MCI and its energy kite scheme to shake us down. We HAVE to build large scale energy and desalinization plants in our typical California grand way to solve these problems. When we do, the same GOP hog/beggars from AZ,UT,NM,NV will be back with their itchy palms out again. Thank GOD we have those storage 'playas'.
zaphawk
3 / 5 (2) Aug 03, 2017
@Osiris1
"We have helped neighboring beggar states to the east all governed by corrupt rapacious republicans voted in by ignoramuses or the barfly kind for decades, but when WE need help, we get folks like 'script-boy' Shkrelli and his med-kite scheme, or MCI and its energy kite scheme to shake us down. We HAVE to build large scale energy and desalinization plants in our typical California grand way to solve these problems. When we do, the same GOP hog/beggars from AZ,UT,NM,NV will be back with their itchy palms out again."

Any guess why so many people hate CA? Hint: might be the people.
lessel
not rated yet Aug 03, 2017
The California Taxpayer is being forced to spend $380 million dollars to shrink the Salton Sea. The Sea to Sea Project by Gary K Jennings will restore the Salton Sea by importing gravity fed Seawater from Baja Mexico into the Salton Sea. This project can be 100% privately financed by Gary K Jennings and Associates at a cost of $350 million dollars. The USA has donated $100 million dollars to the international project of importing Seawater from the Red Sea into the Dead Sea. Now the USA, California can help restore the Salton Sea by making a long term purchase contract on imported gravity fed Seawater from the Sea of Cortez into the Salton Sea. There are two companies that can desalinate ocean water around the same cost as rain. Plus they can both generate highly profitable zero pollution electricity 24/7 at the same time. Look up Nathan White the CEO of Agess, Inc., The Ecomedia Compass, Joi Scientific., Hydrogen Technology, Inc., Sephton Water Technology, Dr. Carl Hodges, 2G Energy
rrrander
not rated yet Aug 06, 2017
Who cares? Why do they squander any money on this nothing patch of water? The area around it is populated by welfare scumbags.
Da Schneib
not rated yet Aug 06, 2017
Maybe we shouldn't be sucking water out of the Salton Sea in the first place. Just sayin'.

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