Beware benzene

Last updated: Wednesday, November 01, 2006 Print

My boyfriend spends a lot of time working on motorbikes. Occasionally, say every couple of months, he cleans bike parts using benzene, and sometimes this splashes on his skin & clothes. The fumes are very strong. Is occasional exposure like this dangerous?

In the modern world, we’re exposed to toxic substances every day. They can become so familiar that we forget just how dangerous some of these are. Benzene is a prime example.

What is benzene?
Benzene is a highly toxic, hazardous chemical and a known human carcinogen, so any exposure to it should be avoided if at all possible. It is a colorless or light yellow liquid at room temperature, with a sweet odour, and evaporates rapidly.

Benzene is formed from the burning of fuels, such as wood, coal, oil and petrol – and tobacco. It is used in many industries, such as those used to make plastics, resins, synthetic fibres, detergents and pesticides. It is also often used as a solvent – for cleaning motorbike parts, for example.

How you may be exposed to benzene
Everyone is exposed to low levels of benzene. It is found in:

Tobacco smoke. This is an important exposure route
Motor vehicle exhaust
The air around petrol stations, industries and hazardous waste sites
Indoor air. This often contains levels of benzene even higher than in outdoor air, from products that contain benzene such as glues, paints, furniture wax and detergents.
Benzene can sometimes leak from underground storage tanks or hazardous waste sites, and can contaminate ground water.
People who work regularly with benzene or products containing it have a higher risk of developing associated health problems. This includes mechanics: in addition to exposure when using benzene as a cleaning solvent, mechanics can be further exposed to the benzene in petrol.
Health effects
Benzene can be inhaled or absorbed by the skin. It is also dangerous if swallowed. High levels can cause drowsiness, dizziness, headache, rapid heart beat, tremors, confusion and unconsciousness. Ingested benzene can cause vomiting. Very high levels of benzene exposure can be fatal.
Long-term exposure to high levels may cause leukemia and anaemia, and weaken the immune system; benzene has also been implicated in other long-term health problems. The risk for cancer is generally considered significant only for people who work with or around benzene for many years, or who have repeated high exposures. However, much remains uncertain as to whether lower exposures could be a risk factor for certain people; remember also that we are exposed to other toxic and/or carcinogenic substances in the environment besides benzene.
Safety tips when working with benzene:
- Work in a well-ventilated space, preferably outside.
- Benzene is highly flammable, so keep it away from heat, flames or sparks.
- Wear impermeable gloves to avoid skin contact with liquid benzene, and consider wearing a respirator to avoid inhaling fumes. Such respirators, which use replaceable cartridges, can be obtained from reputable hardware stores. (Note: dust masks may help prevent inhalation of airborne droplets, but not gaseous fumes.) A work overall or apron is also a good idea.
- If you’ve inhaled benzene and experience any worrying symptoms, remove yourself from further exposure to where you can breathe fresh air, and call your doctor immediately.
- If you get liquid benzene on your skin, wash it immediately with soap and water. If you’ve splashed benzene on your clothes, take them off quickly and wash them.
- If benzene splashes in your eyes, rinse them with water for at least fifteen minutes, and call your doctor. Remove contact lenses, and don’t reinsert them.
- If someone swallows benzene, don’t try to make them vomit or give them anything to drink. The vomit may be inhaled and damage their lungs.
(Olivia Rose-Innes, EnviroHealth Expert, Health24, November 2005)