Home Science Environment Researchers Detect Bromine Atoms in Springtime Arctic

Researchers Detect Bromine Atoms in Springtime Arctic

For the first time, researchers at the University of Michigan have detected bromine atoms in the atmosphere, and in doing so, have confirmed the reaction pathway through which mercury is removed from the atmosphere and enters the ecosystem in the springtime Arctic.

Mercury is a particularly toxic pollutant largely emitted through human activities such as coal-burning power plants. Because it’s long-lived — meaning it does not react with many compounds in the atmosphere — it collects in remote regions such as the Arctic, according to U-M chemist Kerri Pratt.

Mercury can be a serious public health hazard. When it enters the ecosystem, it accumulates in fish. The further up the food chain the fish is, the more mercury it accumulates. Researchers have long suspected that bromine reacts with ozone, a greenhouse gas, and mercury, but no one had measured bromine atoms in the atmosphere.

Senior author Pratt and her team, which includes first author Siyuan Wang, now an Advanced Study Program postdoctoral fellow at the National Center for Atmospheric Research, have published their results in the Proceedings of the National Academy of Science. Pratt, the Seyhan N. Ege Assistant Professor of Chemistry, said:

The unique chemistry happens when sunlight hits the salty snow in the Arctic. Chemical reactions in the surface snow produce what’s called molecular bromine — two bromine atoms hooked together. When sunlight hits this molecule, it breaks up to form bromine atoms.

Bromine is so reactive and at such low levels that it is very difficult to measure in the atmosphere, according to Wang, who led the work as a postdoctoral fellow in the Pratt lab. Together with Pratt,  lab doctoral student Stephen McNamara spent a lot of time in the lab synthesizing bromine atoms at extremely low levels to prove their Arctic measurements. Wang said:

The researchers set up sampling instruments on the Arctic tundra. Air is sucked through a carefully designed inlet into a device called a chemical ionization mass spectrometer. The spectrometer measures the masses of the products in the sample, which tells the researchers what was in the air.

Bromine atoms are also difficult to measure because there are few places they exist on Earth, according to Wang. These places include above Arctic and Antarctic snowpacks and above the tropics in the upper troposphere — located about 8 miles above Earth, Wang added:

Researchers Daniel Obrist, then at the Desert Research Institute and now at the University of Massachusetts, Lowell; Christopher Moore, of the Desert Research Institute; and Ralf Staebler and Alexandra Steffen, of Environment and Climate Change Canada, made the mercury measurements. Additional researchers on the team included Angela Raso and Paul Shepson of Purdue University. Pratt ended with:

Provided by: University of Michigan  [Note: Materials may be edited for content and length.]

Like this article? Subscribe to our weekly email for more!     

Troy Oakes
Troy was born and raised in Australia and has always wanted to know why and how things work, which led him to his love for science. He is a professional photographer and enjoys taking pictures of Australia's beautiful landscapes. He is also a professional storm chaser where he currently lives in Hervey Bay, Australia.

Most Popular

Hold on, 12 Young Hong Kong Protesters!

Carry on, young Hong Kong protesters! A few months ago, 12 young Hong Kong protesters attempted to flee Hong Kong to Taiwan without success. Some speculate...

Chinese Calligrapher Creates Artwork Reflecting the Pandemic Era

Liu Xitong is a renowned calligrapher from China who recently took part in a documentary by NTD Television titled "When the Plague Arrives." The...

Climate Change Report Claiming ‘Point of No Return’ Exposed

A recent fear-mongering report that claimed humanity is ‘beyond the point of no return’ when it comes to climate change has been debunked by...

Beijing Is Weaponizing Biotech for New Age Biological Warfare

The COVID-19 pandemic has shined a spotlight on the dangerous possibility of biological warfare. And China seems to be preparing for such a war...