Great Salt Lake Dust Information and Frequently Asked Questions

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The answers to frequently asked questions on Great Salt Lake dust and the potential for Great Salt Lake dust to harbor toxic pollutants are based on our monitoring data over the last two decades and scientific peer-reviewed research.

Note: The air quality around the Great Salt Lake is currently in attainment for particulate matter (PM10 and PM2.5), which means dust pollution, measured as particulate matter meets the federal standards set for particulates by the EPA. 

What is Great Salt Lake dust? 

Great Salt Lake dust is predominantly composed of airborne desert soils and dry lake bed sediment generated during severe wind events. The Great Salt Lake is a terminal lake, which means water flows in but does not flow out, allowing dissolved minerals and metals to accumulate in its sediments. Decades of water diversion and drought have caused the lake’s surface area to shrink dramatically, exposing approximately hundreds of square miles of dry lakebed depending on the lake water level measured as water surface elevation above sea level. Further, variations in surface factors such as vegetation cover, chemical soil crust stability, and moisture content create dust “hotspots” or approximately 8% of Great Salt Lake exposed sediments potentially generating dust. Most of the exposed lakebed has a fairly solid crust that helps prevent dust from easily becoming airborne. 

What is in Great Salt Lake dust and should I be worried?

Exposed Great Salt Lake sediments contain both naturally occurring and industrially-sourced heavy metals such as arsenic, cadmium, cobalt, copper, lead, mercury, and thallium that may reside in entrained dust. Based on numerous published science [(Putman et al. 2025; Jung et al. 2024 ; Lopez et al. 2024 ; Wurtsbaugh et al. 2020; Perry et al. 2019], exposed Great Salt Lake dry lake bed sediments do have relatively high levels of heavy metals resulting from anthropogenic activities and natural geological and hydrological processes, but the concentrations of these heavy metals in airborne dust remains unclear. For example, Munroe et al. (2025) found that dust in Salt Lake City and Provo relative to upwind natural areas was slightly enriched in copper, cadmium, and lead but not arsenic, cobalt, or thallium.

We have actively monitored heavy metal concentrations in PM, but only at a limited number of stations as part of the Chemical Speciation Network and National Air Toxic Trends Network. Great Salt Lake dust events contain airborne sediments that fall into both the PM10 and PM2.5 pollutant category. 

We have not captured increasing levels of arsenic or other toxic metals in PM10 or PM2.5 particulates over the last several decades in association with dust events or fluctuations in the Great Salt Lake water levels. Further, dust, as PM10, collected by us at five urban locations in the Salt Lake Area from 2022-2023, contained concentrations of all metals below established levels of concern based on hazardous quotients calculated from the Agency of Toxic Substances and Disease Registry and the EPA’s Integrated Risk Information System. Unfortunately, little science exists on the heavy metal chemistry of dust falling on communities surrounding Great Salt Lake. Therefore, we don’t know at this time if heavy metals are lifted into the atmosphere, along with the smaller sediment fractions from the Great Salt Lake, and transported miles to residential centers. 

How May Great Salt Lake Dust impact my health?

Dust occupying the different particulate matter fractions serve as a proxy for inhalable versus respirable dust. Generally, inhalable dust may be deposited in the upper airways like the nose and throat (PM10), while respirable fine dust may reach deep lung tissue (PM2.5). UDAQ evaluates both fractions but mainly focuses on PM10 since it is more easily tractable and contains PM2.5 fraction as well. The EPA’s air quality health standard for PM10 is 150 micrograms per cubic meter (μg/m3), measured over a 24-hour average. If transported to communities surrounding the Great Salt Lake, dust measured as fine particulate matter (PM10 and PM2.5) may be inhaled, causing health issues deep into the lungs, causing respiratory problems like asthma attacks and chronic obstructive pulmonary disease. Heavy metals may influence humans when the dust is inhaled deeply into the respiratory system (i.e., respirable) with metal contamination leading to severe health issues, including cancer, diabetes, and permanent brain damage. Recent studies indicate that sediments from the Great Salt Lake playa and mine tailings exacerbate respiratory issues more than sediments from other desert sources [Attah et al. 2024 ; Cowley et al., 2025]. Great Salt Lake dry sediment is not dust. More research is needed to link potential metals in Great Salt Lake dust to the health of residents along the Wasatch Front. 

How do we know dust heavy metal chemistry? 

We capture dust with sequential filtration instruments, Partisol 2025i Sequential Air Sampler, Thermo Fisher Scientific USA, and measure the mass of dust trapped on the filter samples for PM10 and PM2.5. Next, the concentrations of 38 different metals in the collected dust are analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). 

When am I being exposed to GSL dust? 

Great Salt Lake dust events typically occur during Utah’s spring and fall seasons and are triggered by strong winds from weather systems passing across dry lake sediments. Dust has a peak season with events being more pervasive in the spring from March to May when the passing cold fronts create strong enough winds capable of blowing and transporting dust to our communities. Dust events may also occur in the summer when strong winds accompany summer thunderstorms. 

Am I being exposed to Great Salt Lake dust? 

Dust events are typically short in duration and may only spike particulate matter concentrations for a few hours. If you live in communities along the Wasatch Front, you have the potential of being exposed to Great Salt Lake dust. In late 2023, we added four new PM10 filter monitors to stations close to the Great Salt Lake. These include stations in specific areas near the Great Salt Lake (Lake Park, Prison, and Brigham City), with an additional monitor at Bountiful Viewmont to increase sampling frequency from every six days to daily. From 2023-2025, of the seven monitoring stations in relative close approximation to the GSL, three stations have captured dust, as PM10 events exceeding the EPA standard [150 micrograms PM10 per cubic meter (μg/m3), measured over a 24-hour average]. The exceedances occurred at the following stations: Hawthorne (n=1), Prison (n=1), and Tech (n=2). 

Are all Salt Lake City dust events carrying Great Salt Lake dust?

Not all dust events falling on Central Wasatch Front communities harbor Great Salt Lake dust. Besides Great Salt Lake dust events, dust falling on Wasatch Front Central communities may carry dust from other historic, natural, and industrial dust sources, such as Lake Sevier and Bonneville dry lakes, quarries, and mine tailings. Better understanding of local and regional dust sources, source compositions, temporal fluctuations in dust sources, and what populated areas are most impacted is critical for improved monitoring and ultimately planning to mitigate Utahns’ health.