168 Environmental Biotechnology
linked to diffusers within the vessels to provide adequate illumination within
the filters. An alternative approach has been put forward, using large artificial
lakes, but this would require a much larger land bank to produce the same
effect, since they would have to be very shallow by comparison. It has also been
suggested that cooling the carbonated water first, a feature of both the BioCoil
and ACSACS, would allow normal mesophilic algae to be used, which take up
CO 2 more efficiently. Whether this technique will prove any more successful
in gaining industrial or commercial acceptance than either of the earlier British
systems remains to be seen.
Pollution Detection
One final, and currently emerging, application of phytotechnology to the envi-
ronmental context involves the possible use of plants in a variety of industrial
sectors as pollution detectors. The aim is principally to provide valuable informa-
tion about the toxicological components of contamination from a wide variety of
sources, including the automotive, chemical and textile industries. Unlike biosen-
sors, which tend to be designed around isolated biochemical reactions, in this
approach, the plants are used as entire biological test systems. Moreover, unlike
conventional chemical analytical methods which produce quantifiable, numeric
measurements, the varieties used have been selected for their abilities to iden-
tify contaminants by reacting to the specific effects these substances have on the
plant’s vital functions. Thus, by directing the focus firmly onto the obvious and
discernible biological consequences of the pollutants and then codifying this into
a diagnostic tool, the assessment process is made more readily available to a
wider range of those who have an interest in pollution control.
The development of this technology is still in the initial stages, but it would
appear to open up the way for a controllable method to determine pollutant
effects. It seems likely that they will be of particular value as early detection
systems in the field, since they are functional within a broad range of pH and
under varied climatic conditions. An additional benefit is that they are responsive
to both long-term pollution or incidental spillages and can be applied to either
laboratory or on-site investigations to monitor air, soil or water, even on turbid or
coloured samples, which often cause anomalous readings with spectrophotometric
test methods.
Closing Remarks
The scope of opportunities available to phytotechnological interventions are, then,
wide ranging, though presently, much of this potential remains unexplored. It