Discarded cigarette waste may be a blight on our streets, but researchers are hoping they could someday repurpose it into something useful.
So far, studies have looked into how cigarettes can power mobile phones, make shipping pallets and create stronger concrete.
Now a group of Chinese scientists has come up with a method of using cigarette ash to filter dangerous arsenic from water supplies.
Arsenic, a well-known poison, can be taken out of drinking water using sophisticated treatment methods.
But in places that lack the equipment or technical know-how required to remove it, it still laces drinking water and makes people sick.
A team, led by Jiaxing Li of the Chinese Academy of Sciences in Beijing, coated cigarette ash with aluminum oxide.
Because it has a porous consistency, they suspected that the ash would be better at filtering arsenic than other materials that have been tried previously, such as banana peels.
When they tested the material with contaminated ground water, they found it removed more than 96 per cent of the arsenic, reducing its levels to below the standard set by the World Health Organization.
Naturally occurring and industry-related arsenic contaminates groundwater at high levels in many countries, including Chile, China, Hungary and Mexico.
The odorless, tasteless element can cause skin discoloration, stomach pain, partial paralysis and a range of other serious health problems.
While the technology for removing arsenic from water exists, it is expensive and impractical for rural and developing regions.
Because cigarette ashes are discarded in countries around the world and can be easily collected in places where public smoking is allowed, it could be part of a low-cost solution for a serious public health issue, they claim.
PHOTO CREDIT: Nathan Griffith/Corbis