Great Salt Lake, Greater Toxicity

As the Great Salt Lake (Utah, USA) continues to shrink, exposing more of its lakebed, concerns are growing about the potential health impacts of dust from this increasingly barren landscape. 

Researchers from the University of Utah have recently conducted a study focusing on the chemical composition of dust particles originating from the exposed lakebed. The findings reveal that the dust contains significantly higher levels of reactive and bioavailable metals compared with dust from other regional sources – raising alarms about its potential to harm human health.

To investigate the composition of these dust particles, the research team used inductively coupled plasma mass spectrometry (ICP-MS). Specifically, they analyzed the elemental makeup of PM10 dust particles – small enough to be inhaled and potentially lodge in lung tissue – collected from the Great Salt Lake’s exposed playa and other dust sources in the region, including Sevier Lake, Fish Springs Lake, and Tule Lake.

The results indicate that the dust from the Great Salt Lake contains elevated concentrations of several metals, including arsenic, lithium, copper, manganese, iron, and lead. Notably, the levels of arsenic and lithium exceeded the US Environmental Protection Agency’s residential regional screening levels, indicating a potential health risk for populations living downwind of the lake. 

Analysis also revealed that the dust from the Great Salt Lake has a higher oxidative potential (OP) than dust from other sources, which indicates that the particles could cause oxidative stress and damage to lung cells when inhaled. The study found that the dust’s high OP was closely associated with its metal content, particularly with the presence of redox-active metals.

“We devised a way to dissolve the metals using increasingly caustic acids to figure out at what level these metals leach from the particles,” explained Kevin Perry, co-author of the study,  in a press release. “It turns out that the dust from Great Salt Lake has more leachable metals that are bioavailable than we would wish.”

With only 9 percent of the exposed lakebed currently emitting dust, researchers are concerned that disturbances to the playa crust could exacerbate the issue, leading to increased dust storms and greater health risks for the surrounding communities. As Utah state officials work to address the shrinking Great Salt Lake, gaining a better understanding of the chemical hazards associated with dust from the exposed lakebed could help protect public health.

^{Image credit: Dave Titensor, University of Utah}