Can orange peels fight mercury pollution in our oceans?

An Australian scientist used orange peels and other recycled waste to create an effective and cost-efficient solution that fights mercury pollution. 

In a new report published in the Angewandte Chemie International journal last week, Dr. Justin Chalker of Australia's Flinders University may have developed a citrusy answer to ocean pollution.

Harmful mercury contamination is a serious issue for the world’s oceans. Through biomagnification, mercury concentrations increase at each level of the food chain. In a 2009 US Environmental Protection Agency (EPA) report, 48.8 percent of sampled lakes, or 36,422 lakes, had mercury concentrations that exceeded the recommended human health levels. 

According to the Natural Resource Defense Council, 46 percent of mercury pollution comes from fossil fuel power plants, which emit about 33 tons of mercury pollution annually in the US.

“Mercury contamination plagues many areas of the world, affecting both food and water supplies and creating a serious need for an efficient and cost effective method to trap this mercury,” Dr. Chalker said in a press release.

And Chalker says he may have found the solution. Chalker and his colleagues created a non-toxic polymer from sulfur and limonene. The polymer changes from dark red to yellow as it detects and soaks up mercury.

The best part? Dr. Chalker says the solution is making good use out of what would typically be waste. Sulfur is a common byproduct of petroleum production and limonene is produced by the citrus industry, primarily through orange peels.

“More than 70 million tons of sulfur is produced each year by the petroleum industry, so there are literally mountains of it lying, unused around the globe, while more than 70 thousand tons of limonene is produced each year by the citrus industry,” he said in a press release. “So not only is this new polymer good for solving the problem of mercury pollution, but it also has the added environmental bonus of putting waste material to good use …”

But some environmentalists are say we need to focus our time and resources on preventing pollution before it happens.

“Cleaning up existing pollution is generally more costly and technically challenging than preventing pollution in the first place,” Dr. Lisa Suatoni, a senior scientist at the Natural Resources Defense Council, tells The Christian Science Monitor. “This is particularly the case in the world’s oceans, given the vast volume of water and the circulation patterns in oceanic systems.”

In December 2011, the EPA established the Mercury and Air Toxics Standards (MATS), and reaffirmed their stance in an April 2015 ruling to deny all remaining requests for reconsideration of the standards. MATS requires air pollution reductions from coal and oil-fired power plants, with “technology-based emissions limitation standards for mercury and other toxic air pollutants…” 

MATS is the first set of national limits on mercury and other toxic emissions from power plants. The EPA says the policy standards will cost $9.6 billion. But, in return, MATS will give Americans healthier fish, upgraded power plants, 46,000 short-term construction jobs, and well as 8,000 long-term utility jobs.