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In the last paragraph of the Canberra Times article, the issue of benzene in vehicle emissions was mentioned:- "many of our post-1986 cars have inefficient catalytic converters, causing our unleaded emissions to contain high levels of benzene". A fuller account of the benzene issue is called for, but briefly no matter how "high" the levels of benzene are currently, the levels are lower now than during the reign of leaded petrol:

Lead in petrol prevents the use of catalytic converters as the lead poisons the catalytic converter. Catalytic converters reduce more than just benzene emissions.

In 1996 the CSIRO reported that over the whole fleet (including poorly performing cars) catalytic converters reduce aromatic emissions of benzene on average by 70 per cent

Valerie M Thomas (1995) has reported that:-

The levels of benzene in unleaded and leaded petrol in Australia are essentially the same. Leaded petrol is basically unleaded petrol plus lead (NRMA, 1996). Yet the 1996 CSIRO report showed that using Australian unleaded petrol compared to using leaded petrol in pre-1986 cars even without catalytic converters reduced the volume of emissions of benzene on average by 30 per cent. The reduction of benzene and other aromatic emissions from low octane unleaded fuel may be the result of the more efficient combustion of petrol in the absence of lead.

So in stark contrast to the policy of Octel to promote the dangers of unleaded petrol in regard to benzene emissions in Australia (Gidlow, 1995; Associated Octel, 1995a,b,c&d), Australia has seen an excellent reduction in the total estimated benzene emissions (AIP, 1994) from our car fleet over the period of the phase-down of leaded petrol - both due to more drivers using unleaded petrol in cars without catalytic converters and the fact that all new cars since 1986 have had catalytic converters.

Up to 20% of benzene emissions from vehicles are due to fuel evaporation (AIP, 1995) and since these emissions don't pass through the catalytic converter, evaporative emissions are the same regardless of the efficiency or presence of a catalytic converter (Thomas, 1995)

A World Bank report from 1998 states that "the magnitude of health impacts caused by benzene exposure should be compared to those of lead exposures. [The US EPA] estimated that 47 cases of deaths from leukemia could be attributed to the exposure from gasoline. For comparison, the annual number of deaths avoided by the reduction of lead in gasoline (only one of the positive impacts of reducing lead), has been estimated between 4,000 and 5,000." (Lovei, 1998)

There are far greater concerns about benzene emissions from non-vehicle sources. The exposure of smokers to benzene, for example, exceeds the exposure of non-smokers nearly 10 times (Lovei, 1998)

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