A ten-year historical analysis of urban PM10 and exceedance filters along the Northern Wasatch Front, UT, USA

TL;DR

This study analyzes ten years of urban dust data near the Great Salt Lake, finding no significant increase in toxic metal levels or dust events despite lake size reduction, but highlights ongoing health risks from arsenic and lead.

Contribution

It consolidates historical dust data and metallic analysis to assess environmental and health impacts related to the shrinking Great Salt Lake.

Findings

No significant rise in dust events despite lake reduction

Dust levels linked to winds from specific desert regions

Metallic analysis shows no increase in toxic metals

Abstract

The Great Salt Lake (Utah, USA) is reducing in size, which raises several ecological concerns, including the effect of an increasing area of dry playa exposed by the retreating lake. This study focuses solely on concerns about the toxicity of metals in the dust blowing off the playa. Although considerable efforts have been made to understand aeolian dust in urban areas along the Wasatch Front, located just east and south of the Great Salt Lake, there is still a need to consolidate existing research and to conduct a compositional analysis of the dust found in these urban areas. We investigated the dust reaching urban monitoring sites around the Great Salt Lake that are managed by the Utah Division of Air Quality. By analyzing historical data, we found that the decrease in the Great Salt Lake's surface area has not led to a statistically significant increase in dust events in urban areas. Windrose plots align with prior research, indicating that heightened dust levels in urban areas coincide with winds originating from the south or west, passing over identified playas and deserts such as the Milford Flats, Sevier Dry Lake, Tule Dry Lake, Great Salt Lake Desert, Dugway Proving Grounds, and the West Desert of Utah. Metallic compositional analysis of urban dust was used to evaluate potential health risks associated with the dust using the hazard quotient, air regional screening levels, and cancer risk methods. This analysis revealed no significant increase in concentrations of toxic metals. However, this is not to preclude a risk of dust-related health concerns, especially due to pre-existing arsenic and lead levels.