Rubber pollution, similar to

plastic pollution Plastic pollution is the accumulation of plastic objects and particles (e.g. plastic bottles, bags and microbeads) in the Earth's environment that adversely affects humans, wildlife and their habitat. Plastics that act as pollutants are catego ...

, occurs in various environments, and originates from a variety of sources, ranging from the

food industry The food industry is a complex, global network of diverse businesses that supplies most of the food consumed by the world's population. The food industry today has become highly diversified, with manufacturing ranging from small, traditional, ...

processing chain to

tire wear A tire (North American English) or tyre (Commonwealth English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineeri ...

Synthetic Synthetic may refer to: Science * Synthetic biology * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic elements, chemical elements that are not naturally found on Earth and therefore have to be created in ...

and

natural rubber Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Types of polyisoprene ...

dust and fragments now occur in food, airborne as

particulates Particulate matter (PM) or particulates are microscopic particles of solid or liquid matter suspension (chemistry), suspended in the atmosphere of Earth, air. An ''aerosol'' is a mixture of particulates and air, as opposed to the particulate ...

air pollution Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...

, hidden in the earth as

soil pollution Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activit ...

, and in waterways, lakes and the sea.

Causes

Tyre and road wear particles (TRWP)

Vehicle A vehicle () is a machine designed for self-propulsion, usually to transport people, cargo, or both. The term "vehicle" typically refers to land vehicles such as human-powered land vehicle, human-powered vehicles (e.g. bicycles, tricycles, velo ...

tire A tire (North American English) or tyre (Commonwealth English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineeri ...

wear is a major source of rubber pollution,Emissions Analytics finds pollution from tire wear can be 1,000x worse than exhaust emissions
/ref> other sources can be from

artificial turf Artificial turf is a surface of synthetic fibers made to look like natural grass, used in sports arenas, residential lawns and commercial applications that traditionally use grass. It is much more durable than grass and easily maintained wi ...

(usually made from shredded old tires) and rubber

O-ring An O-ring, also known as a packing or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a round cross section (geometry), cross-section, designed to be seated in a groove and compressed during assembl ...

s and seals. Tyre and road wear particles (TRWP) or tire wear particles (TWP) are a direct result of the road surface abrasion during vehicle transit and are thought to be released into the environment at a rate of 6 million tons year, with the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

and the

European Union The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...

emitting roughly 1120,000 and 1327,000 tons annually. Both brand and season application affect the tire composition but rubber is usually the main component besides several additives such as, oils,

fillers In animal feed, a filler is an ingredient added to provide dietary fiber, bulk or some other non-nutritive purpose. Products like corn fiber (corncobs), fruit fibers (pulp), rice bran, and whole grains are possible fillers. Purpose As source ...

vulcanisation Vulcanization (British English: vulcanisation) is a range of processes for hardening rubbers. The term originally referred exclusively to the treatment of natural rubber with sulfur, which remains the most common practice. It has also grown to ...

chemicals and other chemicals added to increase performance. A concern is that, unlike exhaust emissions, tire wear pollution is not regulated, despite several studies documenting their potential toxicity. Some devices are nonetheless being developed in an effort to reduce the amount of particulates expelled from tire wear and otherwise ending up in the environment. Although not immediately visible to the naked eye, tire dust makes up a significant portion of

road debris Road debris, a form of road hazard, is debris that accumulates on or off a road. Road debris includes substances, materials, and objects that are foreign to the normal roadway environment. Debris may be produced by vehicular or non-vehicular sour ...

. It is believed that between 10 and 18 percent of the TWP released each year enter aquatic environments and can even be found in remote locations due to atmospheric transportation. However, it has been found that sediments are sinks for TWP and that the surface water concentration of these particles is much lower. Understanding the effect of these particles is challenging as the chemical leaching rate from TWP depends on environmental factors such as temperature, pH, and salinity, as well as the particle size and composition of TWP.

Classification

Very fine rubber dust particles can, depending on the classification be counted as

microplastic Microplastics are "synthetic solid particles or polymeric matrices, with regular or irregular shape and with size ranging from 1 μm to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water." Microplastics ar ...

(because rubber is just another

polymer A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their br ...

) or separately, as fine rubber because its constituent

monomer A monomer ( ; ''mono-'', "one" + '' -mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or two- or three-dimensional network in a process called polymerization. Classification Chemis ...

s, the required additives, and the type of chemical bond mesh is slightly different. In a similar vein, rubber pollution is often implicitly mentioned when

is addressed.

6PPD-quinone 6PPD is an organic chemical widely used as stabilising additive (or antidegradant) in rubbers, such as NR, SBR and BR; all of which are common in vehicle tires. Although it is an effective antioxidant it is primarily used because of its excel ...

, an

antiozonant An antiozonant, also known as anti-ozonant, is an organic compound that prevents or retards damage caused by ozone. The most important antiozonants are those which prevent degradation of elastomers like rubber. A number of research projects stud ...

used in rubber tires, has been found to kill salmon when it accumulates into waterways from tire wear pollution.

References

{{rubber Rubber industry Pollution

Causes

Tyre and road wear particles (TRWP)

Classification

See also

References