Although many experimental studies have investigated
the effects of VOCs on plants, almost all have involved
short-term exposure to very large concentrations relative
to ambient air. For example, although not specifically set
up to record experiments into the direct effects of VOCs
on plants, and not completely up-to-date, the United
States EPA web-searchable database PHYTOTOX
(http://www.epa.gov/med/databases/databases.html #-
phytotox) contains, inter alia, data on experiments
where plants have been exposed to substances in the
vapour phase. A manual search of this database for VOCs
(as defined above) yielded 793 entries. However, of these,
only 23 entries involve fumigation with concentrations of