Mould growth in buildings is a major health issue, but most investigat
ions of the indoor air spora still employ culture-based methods. These
are inadequate for assessing exposure, since culturable organisms com
prise a small fraction of the total of potentially allergenic/toxigeni
c units in air. For epidemiological studies, measurement of airborne f
ungal biomass over extended periods may be more relevant than total co
unts. Whilst (1-->3)-beta-D-glucan has been used to assess airborne bi
omass, ergosterol may be the best indicator of exposure. For case stud
ies, patients' serum has been used to detect specific spores on sample
r slides, and both highly specific and less specific antisera could be
used either via fluorescent antibody technique or enzyme-linked immun
osorbent assays. In the future, solid-phase polymerase chain reaction
(PCR) may be used to detect pathogens or other well-characterized pote
ntially harmful species, and in at least some groups mycotoxin/seconda
ry metabolite/volatile profiles may be used in identification. (C) 199
7 Elsevier Science Ltd.