Greenland has areas of very clean water, the like of which just does not exist in developed nations, but also highly polluted water, making it an excellent location for studying the environmental impacts of chemicals

More than 10,000 tons of antibiotics are consumed in Europe each year and an estimated 30-60% of those pass through animals and humans completely unchanged. These different substances can then reach the ocean via hospitals, municipal sewage, fish farms and run-off from agriculture and landfills.

A research group from the University of Gothenburg wanted to examine the potential effects of accumulating antibiotics in the seabed, so off to Greenland they went.

“Greenland has no sewage treatment whatsoever, which means that waste water from inhabited areas is discharged straight into the sea,” says Maria Granberg. “So Greenland is home to both very clean and very polluted waters, which is great for comparing environmentally pristine areas with polluted ones.”

The soft sediments on the seabed act as a reservoir for hard-to-break-down substances that are released into the environment. Even substances that are not discharged directly into the sea gradually find their way there from the land and air via rainwater. This means that antibiotics can affect marine sediment ecosystems over a long period, with detrimental effects on natural marine communities of bacteria, among other things.

The marine sediment bacteria being studied are also important from a global perspective as they metabolize both nitrogen and carbon, which are linked to both eutrophication and climate problems. A key aspect is also that resistance genes can be transferred between bacteria.

“We know very little about how antibiotics affect natural systems and how antibiotic resistance develops and spreads in these systems,” says Granberg. “This knowledge is, however, vital if we are to identify the sources of, and understand, the mechanisms behind the development of antibiotic resistance, which constitutes a threat to both the functioning of ecosystems and human health.”