Three days before the introduction of a new lead-free super gasoline for cars without catalytic converters, gas sellers complained yesterday of not knowing the composition, price or market name of the new fuel. The gas station owners’ union said a request to government officials this summer for information on the new gas, to be sold to the estimated 1,250,000 vehicles that lack catalytic converters from January 1, had been in vain. The switch follows EU environmental directives. Scientists have warned that the potassium compounds in the fuel might have unknown long-term effects. Michalis Petrakis, of the Athens Observatory’s Institute of Environmental Research, said experiments have shown that high concentrations of potassium cause neurological disorders.«Whatever additive we put in gas, it will have harmful effects. There is no magical solution,» he said. Banks, however, are presenting a picture of greater preparedness. By January 5, 100 percent of ATMs are expected to be providing bank notes in euros, while smaller banks will be able to provide all their ATMs with the currency from January 2.