Integrated Environmental Biotechnology - Environmental Biotechnology: Theory and Application - page 250

in both economic and social terms, of the foot and mouth disease (FMD) outbreak,
which paralysed the UK farming industry throughout 2001, has left the rural
community all too well aware of the meaning of biosecurity. Since today's agri-
business is so largely dominated by the demands of the supermarkets, it is neither
unreasonable nor unlikely that guaranteed product quality would be a require-
ment in any industry-wide standard. A clear precedent has already been set in this
respect with the involvement of the British Retail Consortium in the evolution of
the matrix safety code for the treatment and application of sewage sludge to agri-
cultural land. The drive towards so-called 'organic' farming has already fostered
a climate of proliferating, and typically widely differing, compost acceptability
criteria throughout the world. This is scarcely helpful to the average would-be
user of these products, often serving more to confuse than elucidate.
The prospect of widespread uptake in the growth of bio-production crops in
the future has been suggested as one of the routes forward for agriculture. To
echo Senator Harkin's words, farmed resources could well account for much of
what is currently derived from crude oil, either directly in the chemical sense
as an alternative source of the same product, or indirectly as substitutes. In the
final analysis, the acceptance of the latter will, inevitably, depend on factors
which are more societal and economic than scientific or technical and as such,
largely beyond the scope of this topic to discuss. Suffice it to say that, in any
novel application, cost is a major issue and although the potential market may
be enormous, the commercial benefits must be clear. As discussed before, the
attitude of industry will be crucial. There is undoubtedly a strong background
interest in bio-products, but machinery is often extremely expensive, and down-
time is costly and inconvenient. Using a bio-engineered substitute which has not
been tested and approved, often represents a huge commercial gamble, and it
is a risk which few enterprises, understandably, can afford to take. It may be
some time before the oft-quoted image of vast areas of transgenic crop plants
growing the biological equivalents of today's petroleum based products, at no
more cost than cabbages or corn, finally becomes a commercial reality. However,
the beginnings are clear.
The search for a biological method of producing plastics, for example shows
some promise. The ability of some bacteria to produce natural polymers has
been known for some time and a number of attempts at growing plastics have
been made. The products typically proved expensive, costing between three
and five times as much as ordinary plastic and were generally found to be
too brittle for normal use. Poly(hydroxyalkanoates) are a class of natural poly-
mers with thermoplastic properties, which can be synthesised by bacteria, though
the process is itself economically uncompetitive. Using green plants as plastics
factories has promised much greater competitiveness, but guaranteeing the appro-
priate monomer composition is not easy. One solution has been demonstrated
using GM varieties of oilseed rape and cress, engineered to produce poly(3-
hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) a Poly(hydroxyalkanoate) with
commercial applicability, within their leaves and seeds (Slater et al ., 1999). In
effect, this is a perfect example of genetic engineering manipulating the respective