Experts Say Cigarette Butts - Not Plastic Straws - Are Largest Human-Caused Pollutant

The plastic straw has been at the forefront of conversations about damaging man-made waste but cigarette butts have turned out to be an even bigger problem. An estimated 4.5 trillion butts are littered globally each year, The BBC reports, and their effects are incredibly harmful.

A study led by Anglia Ruskin University in Cambridge found that cigarette butts left in grass and soil cause stunt plant growth. The study also suggests cigarette butts are the most pervasive man-made contaminant and the most littered item worldwide.

Researchers found that this waste cuts down the germination success of grass by 10 percent and shortens the shoot length of clover by up to 28 percent. Most cigarette butts contain a filter made of cellulose acetate fibre — a type of a bioplastic which is not biodegradable — and can cause the same damage to plant growth as un-smoked cigarettes.

This problem also extends into the Earth's oceans.

As The Conversation reported, cigarette butts comprise 30 to 40 percent of all litter found in coastal and urban litter clean-ups since the 1980s. Although cigarettes themselves are biodegradable, the filers are not and could take years to breakdown in the environment, even accumulating at the bottom of the deep sea.

Some have suggested banning the filters outright, citing their benefits are minimal compared to their impact on the plant. Earlier this year, California lawmaker Hannah-Beth Jackson introduced a bill seeking to outlaw cigarette filters in an attempt to reduce tobacco product waste.

First published on July 20, 2019 / 11:38 PM

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