Viable Algae in House Dust

Abstract

HUMAN allergic reactions to algae have been documented1, but so far these disorders have been recognized only after exposure to algae-infested waters. A number of investigators have suggested, however, that air-borne algae constitute a source of respiratory hypersensitivity reactions in susceptible individuals2–4. Viable cultures of algae were obtained from atmospheric samples by van Overeem in 19375. More recently, Gregory et al.6, Schlichting7 and Brown et al.3 confirmed and extended these findings. Air-borne dissemination of algae was suspected as an explanation for the high incidence of positive skin reactions, reaginic antibodies, and positive provocative responses obtained in atopic patients tested with aqueous extracts of various species of green algae4. It seemed that one likely source of air-borne algae would be ordinary house dust and we now report the results of our investigation of this possibility.