Pyrene

CAS number 129-00-0

Description

Pyrene is a colourless solid, solid and solutions have a slight blue fluorescence. Pyrene is one of a group of chemicals called polycyclic aromatic hydrocarbon (PAHs). PAHs are a group of naturally occurring pollutants. Pyrene is a natural component of coal tar, crude oil, and fossil fuels. PAHs are created when products like coal, oil, gas, and garbage is burned but the burning process is not complete.

Uses

Pyrene is used to make dyes, plastics and pesticides. It has also been used to make another PAH called benzo(a)pyrene.

People are exposed to pyrene because it is often found in air, water, food, and soil. One of the most common ways people are exposed to pyrene is through inhaling it from car exhaust, cigarette smoke, or fires. Pyrene can also be ingested through eating contaminated food or drinking contaminated water.

Indoor air sources of contamination of pyrene can include: grilling food, as the cooking process can release pyrene; and tobacco smoke

Pyrene is formed when a material, such as gasoline or wood, burns incompletely. Pyrene sticks to very small particles that go into the air. People and animals may breathe in the particles that contain pyrene and other PAHs. The particles and pyrene eventually settle back onto the ground or into ponds, lakes, or rivers. Pyrene can also be washed into water by rain. Pyrene may settle into sediment or soil. When pyrene is attached to particles in soil or water it can be swallowed by animals, including fish or taken up by plants.

Why it can be problematic for human and animal health

Exposure is usually by ingestion but can be by inhalation, especially if near fuels/industrial processes, or dermal contact by swimming in water with pyrene from industrial wastage.

PAHs generally have a low degree of acute toxicity to humans.
The most significant endpoint of PAH toxicity is cancer.
Increased incidences of lung, skin, and bladder cancers are associated with occupational exposure to PAHs. Data for other sites is much less persuasive.
It is difficult to ascribe observed health effects in epidemiological studies to specific PAHs because most exposures are to PAH mixtures.
Animal studies show that certain PAHs affect the hematopoietic, immune, reproductive, and neurologic systems and cause developmental effects.

The following groups of people are thought to be most vulnerable to the chronic exposure of PAHs:

elderly who have declining organ function
young children with immature and developing organs
people who smoke (and therefore inhale PAHs and thus have higher exposure)
have a history of excessive sun exposure (enhanced skin cancer response if simultaneously exposed to PAHs via skin)
have liver and skin diseases
women of child bearing age
an unborn foetus as it is recognised that PAHs may cross the placenta.

Pyrene is shown in scientific literature as being associated with the following chronic health impacts:

Probable carcinogen - breathing PAHs and skin contact seem to be associated with cancer in humans.
Damage to kidneys, including decreased function and weight
Risk to increased liver fat on exposure
Asthma - Damage to lungs has been identified at cellular level – more research needed
Cardiac abnormalities and prenatal injuries demonstrated in animal studies (zebrafish)

Acute exposure of humans to pyrene by inhalation, ingestion, and dermal contact are unknown.

Continued research regarding the mutagenic and carcinogenic effects from chronic exposure to PAHs and metabolites is needed.

Please note any adverse health effects that you may encounter in exposure to a chemical depend on several factors, including the amount to which you are exposed (dose), the way you are exposed, the duration of exposure, the form of the chemical and if you were exposed to any other chemicals.