An information war has been simmering in the U.K. over the risk of leukemia from exposure to benzene in unleaded gasoline.
Associated Octel Co. Ltd., Milton Keynes, U.K., manufacturer of lead based additives for gasoline, is pitted against oil companies.
The argument centers on a government report on air quality standards. This recommended legislating a maximum average benzene in air level of 5 ppb, which should later be reduced to 1 ppb.
Octel said the report dramatically undermines the reputation of unleaded gasoline as a "green" fuel. It said unleaded fuel should be used only in cars fitted with a catalytic converter. Such cars account for less than 10% of the entire fleet in Britain.
Octel claims removal of lead from gasoline gave rise to the benzene health hazard. Current fuels particularly "superunleaded" grades were said to contain increased amounts of aromatic hydrocarbons to boost octane.
Government scientists acknowledge that the source of 78% of benzene in the environment is gasoline engined vehicle exhausts, Octel said.
SCARE STORIES
Jet Petroleum Ltd., the retail marketing arm of Conoco (U.K.) Ltd., has dismissed media coverage of the issue as scare stories. Jet said benzene is not used as a gasoline additive.
Benzene intake from gasoline fumes or car emissions is insignificant compared with cigarette smoke, Jet said.
Average intake of benzene from all sources for a nonsmoker is said by Jet to be 500 micrograms/day, most of which comes from food. Refueling is estimated to give an average intake of 20 micrograms/day.
Shell U.K. Ltd. said the government report shows that average annual benzene concentration in the air of Central London is 4.2 ppb. This is below current targets, although further reductions will be needed.
"Benzene occurs in most forms of vegetable matter," Shell said. "It is released into the air by combustion by burning petrol in a car engine but also, for example, by burning coal on a fire, burning brushwood or stubble in the countryside, or even by barbecuing potatoes."
CANCER LINK
Simon Wolff, toxicologist at University College London, says it has been proved that benzene can cause leukemia, and his. studies show that more cars equate to more cancer.
"My starting point was a study of leukemia in children," Wolff said. "There are big variations in childhood leukemia levels around the country."
Wolff said children are likely to be more sensitive to benzene than adults and less likely to be exposed to other sources such as smoking. Also, he said, regular car passengers are exposed to more benzene than pedestrians.
"We found the highest leukemia levels among kids who are reliant on cars to get to school," Wolff said. "Typically they live in the country, 20 miles from an urban center."
Wolff plans to gather data covering several years to prove the link. Asked what he thought of the oil companies' view that there is no evidence that benzene from fuel is a threat to health, he said: "Well, somebody is wrong."
Copyright 1994 Oil & Gas Journal. All Rights Reserved.
