Specific bronchial Provocation tests with shell powder extract were performed on the subjects who had respiratory symptoms.

Positive skin responders to shell powder extract were 8 among the 26 subjects (30.8%), and subjects who were positive responders to any one of 12 common allergens showed a higher positive rate than negative responders. Among the 8 subjects who had a positive skin response, four had respiratory symptoms. Three subjects were positive bronchial responders to bronchial provocation tests.