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Friday, March 29, 2013

Put the Kybosh on Pesticides

DDTA vast number of synthetic organic compounds have been produced for use as pesticides in the agricultural industry.  Pesticides include but are not limited to the sub-categories of herbicide, insecticide, and fungicide.  A pesticide is designed to kill a pest, obviously, and you can see from the root name of the sub-category which type of living organism is targeted.  The trouble is, most pesticides are non-selective.  In other words, many innocent bystanders (non-targeted 'pests') are also harmed in ways that cannot be anticipated (see DDT case history  Pesticides are developed and approved for use long before the unintended consequences are realized.
Great controversies, such as the Proposed Ban in Europe and Bee Colony Collapse Disorder in the US, are brewing today over the use of neonicotinoids (sub-category of insecticide).  Concerns run far and wide, and they should, so let's look at some of the pesticide occurrence research.
Triple E Agent Assignment:
Present classes of pesticides and delve into the classes that generally target insects...
What are the basics, according to research on Environmental Pollution?

Pesticides are also classified by chemical makeup as carbamates, chloroacetanilides, chlorophenoxy acids, organochlorines, organophosphates, pyrethoids, and triazines.  Of these, organochlorines, organophosphates, and pyrethoids commonly target insects.  Can you believe that some of these were directly applied to the skin? (see photo below)

Organochlorines are compounds that contain at least one covalently bonded chlorine atom.  They are commonly used as agricultural insecticides, are highly persistent in the environment, and are known for their high toxicities (see 10 Most Toxic Pesticides Found in Water).  Organochlorines that have high frequencies of occurrence in the environment include 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), dieldrin, lindane, and methoxychlor.  By 'occurrence' - Triple E means that these compounds are now found in waters that would never naturally have detectable concentrations - they are synthetic (i.e., man-made) after all.

Organosphosphates are commonly used as insecticides because they act as neurotoxins.  They are considered less persistent and less bioaccumulative than most classes of pesticides, but have the potential to be more toxic than organochlorines or carbamates.

Pyrethroids are commonly used as insecticides, and can be persistent in the environment.  Pyrethroids have a low toxicity relative to other pesticides (specifically the organochlorines) so have recently been used in place of more toxic pesticides.  Biphentrhin, cypermethrin, and esfenvalerate are among the most widely used pyrethroids.

Studies have shown that organochlorines and organophosphates have the potential to cause adverse effects on biota and humans.  Pesticides such as diazinon, methoxychlor, and dieldrin occur frequently in runoff waters and pose a human health hazard at environmental concentrations.

Neonicotinoids (a new class?) are the new insecticide of choice in many places because they are believed to be less toxic than organophosphates and carbamates.  They are applied to corn, rapeseed (now more commonly referred to as canola), apples, carrots, strawberries, and other fruits and vegetables.  But are they harming bees? You know, honey bees - Nature’s answer to pollinating apples, cherries, watermelons, onions, soybeans, canola, sunflowers, and almonds and so on and so on.  In addition to undefined neurotoxicological effects of the neonicotinoids, there are also increases in other pesticides due to genetically modified crops (GMOs) which are able to tolerate higher doses of some herbicides and fungicides.

Sounds like a Snowball Effect to Triple E!  Not sure when it will end, but it might be best to learn lessons from those that are returning to organic and pesticide-free agriculture.

Much More to Tell,
Triple E.

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