Agriculture Reference
In-Depth Information
in universities is often funded by self-interested parties. The
extent to which this affects the results and conclusions of
research is impossible to tell. So I am going to give you
information on two synthetic insecticides, understanding that
the research I have available says they are safe but that it
could be discovered later that you shouldn't touch them with
the proverbial 10-foot pole.
The use of natural insecticides like pyrethrin is perfectly
acceptable under the National Organic Program, but in
practical terms these substances are every bit as toxic as
commonly available synthetics while being less effective in
many instances. The main difference is that the natural
insecticides break down into nontoxic compounds very
quickly under the influence of heat, sunshine, wind, and rain
so they won't make it into your food supply if used properly,
whereas the synthetics are specifically formulated to be more
persistent.
Let's take pyrethrin as an example. Pyrethrin is a natural
neurotoxin that insects quickly absorb through the skin. Once
it is absorbed, the race is on between the insect's enzymes
that detoxify the pyrethrin and the pyrethrin's toxic effects.
Many insects, if they receive a sublethal dose, will pick
themselves up and dust themselves off less than an hour after
apparently being killed! Synthetic pyrethrins approach this
problem by mixing the product with a substance like
piperonyl butoxide that delays the insect's ability to make the
enzymes to detoxify the pyrethrin, thus lowering the threshold
considerably for what would constitute a lethal dose.
Moreover, semisynthetic pyrethrins, such as allethrin, are
often more toxic to insects while being less toxic to mammals
(such as humans) than their natural counterparts.
