5D: An increasing threat of toxic dust from a drying Great Salt Lake

Janice Brahney | Chapter Five: Great Salt Lake

TAKEAWAY

Dust emissions from the dry lakebed are increasing and may transport contaminants to communities and ecosystems downwind.

Some locations on the playa have been transformed into major dust hotspots.

Dust from the drying Great Salt Lake is an increasingly serious threat to health, the economy, and ecosystems in Utah. Airborne sediments from the dry lakebed carry heavy metals that accumulated in sediment over time from sources in industry, agriculture, and metropolitan pollution. Researchers are now investigating the production, transport, and composition of Great Salt Lake dust to understand the potential effects of the shrinking lake on factors such as human health, agriculture, and ecosystems in the region.

Preliminary research results suggest that, beginning in the late 1990s, dust emissions have increased and are increasingly severe, especially over the past decade. Dust generated from the lakebed contains man-made toxins as well as cyanotoxins from historic algal blooms and has potential to be more detrimental to human health than dust generated from other sources. Dust samples contain relatively high concentrations of arsenic, cadmium, lead, copper, and mercury.

Certain areas of the lakebed are getting dustier over time. Under increasingly dry conditions, with more of the protective salt crust weathering away, some locations on the playa have been transformed into major dust hotspots. Researchers believe that the frequency of dust storms in northern Utah are connected to the size of the exposed lakebed. Violations of the National Ambient Air Quality Standards for fine particulate matter will likely become more frequentthe longer the lakebed is exposed. High concentrations of fine particulate matter (PM2.5, PM10) pose an acute health hazard, regardless of the chemical composition of the particles.