Cigarette butts – the most common form of litter on the planet – significantly reduce plant growth, according to new research.
Researchers from Anglia Ruskin University have conducted the first-ever study showing the damage that cigarette butts can cause to plants. According to lead author Danielle Green, the presence of cigarette butts in the soil had a detrimental effect on the germination success and shoot length of both grass and clover, and reduced the root weight of clover by over half.
More specifically, the researchers believe that the chemical composition of the filter is what is causing damage to plants. “Most are made from cellulose acetate fibres, and added chemicals which make the plastic more flexible, called plasticisers, may also be leaching out and adversely affecting the early stages of plant development,” said co-author Base Boots.
An estimated 4.5 trillion cigarette butts are littered every year, making them the most pervasive form of plastic pollution on the planet. As part of the study, the researchers sampled locations around the city of Cambridge and found areas with as many as 128 discarded cigarette butts per square metre. Some parks had over 100 cigarette butts per square metre, particularly surrounding benches and bins.
“Dropping cigarette butts seems to be a socially acceptable form of littering and we need to raise awareness that the filters do not disappear and instead can cause serious damage to the environment,” says Green, adding that filters can take years, if not decades, to break down.
For their study, the researchers tested ryegrass and white clover, both of which are important forage crops for livestock as well as being commonly found in urban green spaces. White clover is especially important for pollinators like bees.
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