INDOOR MOULD, DUST MITE AND ENDOTOXIN EXPOSURE IN ABORIGINAL HOUSING IN BRITISH COLUMBIA: AN ASSESSMENT IN THE HEILTSUK FIRST NATION COMMUNITY

Concerned with mould exposure in reserve housing, the Heiltsuk First Nation participated in a CIHR-funded research project to assess residential indoor air quality. Biological particles including moulds, dust mites and endotoxins, and questionnaires based on health status and home environment for 43 homes were studied to understand exposure risks (determinants of exposure). The Heiltsuk were partners in this research project. They consented to the initiative and implementation of the project, shared their knowledge and were the trainers and the trainees — examples of self-determination. Odds Ratios (ct = 0.05) were applied to air and dust samples and compared with the questionnaires. The geometric mean (GM) for indoor airborne mould concentration was 509 CFU/m3 (range 7 — 18,582 CFU/m3). In bedroom carpet samples, dust mite protein, DerPi, levels ranged 0.1 — 150 pg/g (GM 15 pg/g). In other rooms, levels ranged 0.1 —55 pg/g (GM 1.3 pglg). DerP2 levels ranged 0.1 — 180 pg/g dust (GM 14.7 pg/g) for bedroom samples and 0.1 — 110 pg/g (GM 2.1 pg/g) in other rooms. An association was found between bedroom dust samples and mite sensitization levels (>2.0 pg/g) for DerPi (OR 5.5; 95 % Cl 1.194—25.51 7; p = 0.029) and DerP2 (OR 10.1; CI 0.922 — 111.247; P = 0.058). An association was also found between levels of mould concentrations and reported respiratory treatment (OR 8.2; Cl 1.977 — 34.431; p = 0.04) but not with levels of dust mite concentrations. Indoor to outdoor fungal ratios exceeding unity were associated with reporte