Antarctic pollution puts marine environment at risk

A new study investigating Antarctic pollution near Australia’s Casey Station has found that some sediment contaminant levels exceed international guidelines.

Located 3,880km due south of Perth, Australia, Casey Station is one of three permanent research outposts in East Antarctica.

The Australian Antarctic Division (AAD) monitoring team undertook the latest survey.  Their findings identified how long pollutants contaminated the environment, and how variable each of the sites were.

The researchers say: “research stations such as Casey are likely to pose a moderate level of long-term ecological risk to local marine ecosystems through marine pollution.”

The findings have been published in the journal PLOS ONE.

Scientists monitored marine pollution at Casey Station from sediments at surrounding sites, including wastewater outfalls, the wharf area, two former waste disposal sites, and control locations.

They measured the presence of metals, hydrocarbons, nutrients, ‘polybrominated diphenyl ethers’ (PBDEs), a class of fire retardant chemicals added to a variety of manufactured products, and ‘polychlorinated biphenyls’ (PCBs), used in industrial products from the 1930s to the 1970s.

In the sediments, which date from 1997 to 2015, they found consistently higher concentrations of contaminants at locations disturbed by humans.

Some contaminants exceeded international guidelines for sediment quality, including metals, hydrocarbons, and PCBs.

Dr Jonny Stark, a Principal Research Scientist with the AAD East Antarctic Monitoring Program and lead author of the report says the variability of the sites suggests that ongoing monitoring should be more substantial: “The measurement of pollution at the sites can vary substantially within just a few metres.” He says this highlights the need for well designed monitoring programs.

The survey revealed that despite improved environmental management practices over the past 20-30 years, contaminants in marine sediments in disturbed locations have remained at similar levels or are increasing.

Stark says Australia takes environmental stewardship seriously, and has implemented a process to remove all waste from the sites.

However one of the rubbish tips from decades ago: “couldn’t have been at a worse place for the environment, really.”

The dump was removed in 2004.

Cosmos: Is tourism melting Antarctica?

Stark says regarding wastewater, “there is more work to be done,” and it’s expected a project in place will ensure, within a few years, that only pure water is returned to the ocean.

“Australia was one of the first countries to look at the environmental impact of our stations.”

According to the researchers, Casey Station is an example of a fairly typical Antarctic research station – particularly the ones established prior to 1980.

Stark says: “Raising awareness of the contamination risks associated with Antarctic stations and implementing monitoring programs for marine environments adjacent to these stations can contribute to informed decision making and the improvement of environmental management practices in Antarctica.”

The Australian Antarctic presence at its three stations varies from about 100 people over winter to several hundred over summer. The giant US McMurdo station holds up to 1500 people in summer.

New Zealand, China, the US, Russia, India all have research stations in Antarctica.

Environmental discharge is regulated by the Madrid Protocol of 1991, which led to the establishment of the  Committee for Environmental Protection (CEP) to the Antarctic Treaty.

Stark hopes reports like this will help inform the CEP and lead to improvements in policy across the region.