Benzene, a sweet smelling hydrocarbon with a dark and dangerous side.
Benzene… we’ve all heard the name, but what exactly is it? If one were to get technical, benzene would be described as an organic chemical compound having a molecular formula C6H6 – six carbon atoms joined in a ring, with one hydrogen atom attached to each of the carbon atoms.
First derived from a benzoin resin known to pharmacists as early as the 15th century, benzene as we know it today was initially distilled from benzoic acid (flowers of benzoin).
Sweet smelling and colorless, benzene’s initial major claim to fame was in the 1930’s as a solvent used in making the first de-caffeinated coffee – Sanka. A host of other products used benzene up until the 1970’s – Liquid Wrench, paint strippers, rubber cements, spot removers and others.
In fact, benzene could then be bought in most hardware stores just like paint. Students regularly used benzene in chemical experiments, unaware of its cancer and leukemia causing properties.
But as the darker side of benzene began to show up in illnesses and deaths, its general public uses have been understandably curtailed or eliminated altogether. (Lucky for us decaf coffee drinkers!)
Benzene as a Natural Byproduct
It’s interesting to note benzene also occurs in nature. Wherever carbon-rich materials are partially burned, benzene can be found. Forest fires and volcanoes are two such sources. It’s also found in cigarette smoke – something to seriously consider before you light up and puff away!
If you burn PVC – polyvinyl chloride – one of the world’s most used plastic materials and the stuff many of our plastic pipes are made of, benzene will be a major component and pollutant. (Have you ever noticed when plastic burns it has a sweetish odor? Now you know why – it’s the benzene.)
However, benzene is currently used quite frequently in and for industrial applications.
Up until World War II, most benzene was derived as a byproduct from steel production, nick-named “coke-oven light oil.” By the 1950’s however, demand was so great, most benzene was coming as a derivative of the petro-chemical industry.
Today, industry uses benzene to make other chemicals – which then turns out a host of important products. 80% of benzene production goes into producing:
- Ethylbenzene – needed to create styrene, a major component of plastics and polymers.
- Cumene – for creating adhesives.
- Cyclohexane – used for making Nylon fibers.
Other uses for benzene include explosives and pesticides, as well as being part of lubricants, detergents and even some prescription drugs!
Benzene in Gasoline
Benzene has been given a second life in the gasoline industry. Originally used to prevent engine knocking, it was largely replaced in the 1950’s by tetraethyl lead. Since leaded gas has all been phased out, benzene is once again being used – albeit at a ratio of about one percent of the total gas volume.
Benzene and the Environment
It would be nice to think benzene exposure would be limited to factories where proper precautions could be taken for reducing its harmful effects. However, that’s not the case. Here are the major sources of benzene exposure for the average person:
- Tobacco smoke
- Automobile service stations
- Auto & truck exhausts
- Industrial emissions
- Contaminated water
In today’s society, literally each time you step outside you’re exposing yourself to a little more benzene.
Coming up: “Benzene and Disease – What You Should Know!”