A new, affordable, non-toxic polymer has been found to be capable of taking mercury out of water and soil – and the often-discarded orange peel may be the key to getting it.

The dark red material discovered by Dr. Justin Chalker of Flinders University in Australia is obtained from two industrial wastes: sulphur and limonene, which is found primarily in orange peels. The material becomes bright yellow once it absorbs mercury, one of the worst pollutants in the world today.

According to the new study to be published in the journal Angewandte Chemie International Edition, this polymer is cheap to produce because sulphur and limonene are abundant globally and may in fact benefit large-scale ecological cleanups. The material can also coat domestic and waste water pipes or aid in mercury removal in large water bodies.

“Mercury contamination plagues many areas of the world,” warned Dr. Chalker, who also noted that both food and water supplies can be contaminated by this heavy metal, which is shown to damage the central nervous system and particularly hound the safety of women and children.

Mercury can enter the human body through skin or ingestion, such as consuming mercury-laced fish.

Dr. Chalker said that until now, there wasn’t an efficient, cost-effective way to trap mercury.

The new sulphur-limonene polysulfide is believed to be viable given the over 70 million tons of sulphur produced by the petroleum sector each year, as well as the more than 70 thousand tons of limonene from the citrus industry.

An extra “environmental bonus” was also discovered by Dr. Chalker. The material can serve as a mercury detector because it turns yellow after a chemical reaction with the heavy metal. This allows the material to clear away toxic metals from water and be easily removed and replaced once it is used. 

The National Resources Defense Council indicates that mercury is also emitted to the air by power and cement plants, some chemical producers, and other industrial facilities. While it is no longer commonly used in thermometers and other household items, experts have sounded the alarm on the rising level of mercury in fish.

Through biomagnification, the potent neurotoxin can be stored in huge quantities in fish and other predators found at the top of the food chain.