Campaigning yesterday in New York City, Ralph Nader, the Green Party presidential candidate, criticized General Electric for polluting the Hudson River and called on the major parties’ candidates, Al Gore and George W. Bush, to return campaign contributions from the company. Nader, speaking about PCB pollution in the river, said, “It is time for General Electric to obey the law and pay for its poisoning of the Hudson River and stop lying and deceiving the public about the dangers.” Meanwhile, Gore in Seattle yesterday promised that as president he would convene a “salmon summit” to work out ways to restore salmon runs and pledged that his administration would “attack global warming, reduce pollution, stop sprawl.”