Â鶹ÒùÔº

A research team, led by Professor Sung-Deuk Choi from the Department of Civil, Urban, Earth, and Environmental Engineering at UNIST, has developed a novel assessment technique to accurately identify the sources and spatial-temporal distribution of atmospheric mercury. The study has been in the Journal of Hazardous Materials.

This technology relies on high-resolution atmospheric monitoring and mercury isotope analysis. By analyzing the ratios of various mercury isotopes, researchers can effectively trace the origins of atmospheric mercury. The technique enhances accuracy by categorizing mercury sources into three distinct groups for analysis.

Using this assessment method, the research team conducted a comprehensive analysis of the atmospheric conditions in Ulsan over the course of one year, collecting samples from 30 different locations.

The findings revealed significant seasonal and spatial variations in mercury concentrations, with an average concentration of 9.3 ng/m³ recorded during summer, the highest of any season, and a low of 4.4 ng/m³ during the fall. Intriguingly, the highest concentration—21.9 ng/m³â€”was measured in a non-ferrous industrial complex, suggesting that this sector is a major contributor to mercury emissions.

The study also highlighted the critical role of seasonal winds in the dispersion of mercury. During the summer and spring, prevailing southeasterly winds facilitated the transport of mercury emitted from coastal industrial sites into the inland areas of Ulsan.

In contrast, during the fall and winter, northwesterly winds carried atmospheric mercury toward the East Sea, resulting in lower mercury concentrations. Notably, 73% of the mercury levels in summer were attributed to anthropogenic emissions, predominantly from the non-ferrous metal industry.

The research team is currently conducting long-term analyses in other industrialized regions, which they believe will also help in accurately assessing the contribution of cross-border mercury transport from neighboring countries.

Mercury poses serious health risks, including damage to the brain and kidneys, respiratory diseases, gastrointestinal disorders, elevated blood pressure, and skin rashes. Prolonged exposure can lead to mercury toxicity and Minamata disease, a severe condition linked to mercury poisoning. Due to its low boiling point and vapor pressure, mercury can exist in gaseous form in the atmosphere.

Professor Choi stated, "While the detected mercury concentrations do not exceed the U.S. Environmental Protection Agency (EPA)'s recommended standard of 300 ng/m³, the persistent nature of mercury as a pollutant underscores the importance of ongoing monitoring and management of industrial sites."