Introduction:
From the 1950s, the use of cigarettes with filter increased significantly. These filters are made of cellulose acetate, which is a plastic. Cellulose acetate breaks up into microplastics when it ends up in the environment. On top of that, many toxins are left behind on this plastic filter after smoking. A large proportion of smoked cigarettes (the cigarette butt) is thrown on the ground and forms an important source of litter.

Material and Methods:
We did a literature review on the effects of discarded cigarette butts on the environment.

Results:
behaviour and abilities of water organisms, which are even deadly. The effect of cigarette butts on land animals is something smaller, except when they drink from water that has been polluted by cigarette butts. E.g., mice drinking such water may be less effective in fleeing from predators. Cigarette butts in farmland cause a slower crop growth. Nicotine seeping away from discarded cigarette butts may also end up in herbs and vegetables intended for consumption.

Conclusions:
On July 3, 2021, the European 'SUP' (Single Use Plastics) directive entered into force. This directive should limit the single use of plastic, leading to less plastic pollution of the environment, including that of cigarette filters. From 2023, tobacco companies will be responsible for the cleaning up of plastic pollution from cigarette butts, which is a result of the so called Extended Producer Responsibility. Tobacco manufacturers become responsible for contributing to reducing the litter of those tobacco products in the environment by covering costs of government measures, as well as the costs for public collection systems for the waste of those products, and the placement and exploitation thereof. A Dutch study found that a significant (70%) reduction of cigarette butts in the environment can only be reached with a prohibition on filters, which is only feasible in an EU context.