Efamol Neutraceuticals in Boston, a unit of Efamol Ltd. in Guildford, England, said yesterday that it had named Kirshenbaum Bond & Partners in New York as the first agency to introduce its nutritional supplement products in the United States. Billings were estimated at $10 million. The decision came after a two-month review that had been narrowed to Kirshenbaum Bond and one other finalist, Arnold Communications in Boston.