A group of American and Canadian maritime officials Wednesday began the second leg of a four-nation tour designed to interest Europeans in shipping through the St. Lawrence Seaway.

The annual trade mission run by the U.S. government's St. Lawrence Seaway Development Corp. arrived in West Germany after meeting with shippers and shipping executives in Rotterdam earlier this week. Next week, the 26-member group will visit Vienna, Moscow and Leningrad."The European business with the Great Lakes is likely to increase a little in coming years, but they will always face competition from East Coast ports, which are very popular here," said Cees Hoogerwaard, of Husson Huijsman Agencies BV, a Dutch shipping agent. "But it's good for shippers here to see people out trying to sell what they have to offer."

He added that he felt the mission made a good impression on its Dutch counterparts.

About 125 people attended a presentation in Rotterdam Monday by James L. Emery, Seaway administrator and leader of the mission. Mr. Emery outlined the Seaway's new information systems and emergency response procedures for dangerous cargoes as well as alternative delivery procedures for winter months when the Seaway is closed to shipping.

Mission members described the meetings as an avenue for maintaining contacts and learning about future markets, not pressing for immediate deals.

"After these trade missions, one goes home and asks, 'Well, what did you book?' But you can't put a tonnage figure on it, it just doesn't happen that way," said William E. Gard, vice president of marketing for the Fedcom division of Montreal-based shipowner and operator Fednav Ltd.

The Seaway mission's upcoming Soviet visit has attracted special attention in view of the growing optimism about future U.S. trade with a democratic Eastern Europe.

"With the events in Eastern Europe, the timing of our trip to the Soviet Union is certainly a stroke of good luck and good fortune," said Kenneth J. Szallai, director of the Port of Milwaukee. "We want to get a feel for the tempo of these emerging markets."

Mr. Emery said: "As we retool some of those Eastern bloc countries, we think there are tremendous opportunities in iron and steel, heavy machinery and agriculture."