Paul Kirk Car manufacturers, environmentalists and the oil giant Sasol look set to clash over a controversial petrol additive that is dangerous, destructive and a poisonous menace to people and cars. Sasol says, however, that the manganese- based additive MMT is a safe and cheap substitute for lead in petrol. The company is preparing to import the additive for use on the highveld. Of the two most common additives used to take the place of lead in petrol, the one, MTBE, is a possible cause of cancer and the other, MMT, a suspected neurotoxin. A World Wide Fuel Charter prevents MMT from being added to lead-free fuel. The charter, which was signed by the National Association of Automobile Manufacturers of South Africa, seeks to regulate the qualities of petrol worldwide so manufacturers can standardise engines. Car-makers claim MMT damages catalytic converters and lays damaging deposits down on engine parts, leading to reduced engine performance and increased exhaust emissions.
No date has been fixed for the importation of MMT as Sasol is still engaged in talks with the Department of Environmental Affairs and Tourism. Raoul Goosen, technical services manager for Sasol, is quick to point out that, contrary to the claims of the charter, in Canada the additive has been used for nearly 20 years with no reported serious health problems and no damage to catalytic converters.
Sasol plans to use MMT in lead-free fuel sold on the highveld. They say it will allow cars to perform better by raising oxygen levels in petrol. MMT uses manganese as a substitute for organic lead – the traditional chemical used to increase the oxygen levels in petrol. But manganese is almost as controversial as lead. When ingested through food, manganese is an essential vitamin, but when inhaled the metal is a known neurotoxin that is responsible for so-called “manganese madness” in some miners. Angela Andrews of the Cape Legal Resources Centre is assisting the Environmental Justice Networking Forum to lobby the government to ban MMT before it is imported into South Africa. Said Andrews: “This is a very complicated matter. But put simply we want to be sure whether or not the additive is a toxin before it is put to widespread use, and we do not want to rely on Canadian or American tests. We want tests carried out in South Africa.
“We have no idea what lifelong exposure to low doses of manganese does to people. Bearing in mind the prevalence of HIV in South Africa, our population is much more susceptible to the harmful effects of pollution. We are not as robust as the Canadians or Americans.” Lead-free petrol was first developed not for environmental reasons, but because of the cata-lytic converters required by the American Clean Air Act Amendments. Catalytic converters reduce the amount of carbon monoxide and nitrous oxide that a car emits. However the lead in petrol destroys the converters and so lead-free petrol was developed. Without lead, petrol has a low oxygen content and does not perform as well. Artificial alternatives were soon found though. The most controversial of the lead replacements are MTBE and MMT. Despite initially being seen as a wonder chemical, MTBE is slowly being legislated out of existence in the United States after the Environmental Protection Agency classed it as a possible carcinogen. The state of Alaska banned MTBE when it leaked out of petroleum storage facilities and contaminated groundwater supplies, making 500 people seriously ill. MTBE is presently the subject of at least seven court cases where its makers are being sued for contaminating the environment.