Residue Tolerances for Malathion Sharply Reduced

[WRAPper]

Thanks Tom for the info.
Barley has the same.05 tolerance as wheat so it will de discussed at the barley Sub commitee next week.(as a way to work it to the main commitee)
Really though because practically all grains are graded at point of sale on visual the ability to discern malathion levels to this point is not available in the country. But what likely needs to be done is an information campaign aimed at the elimination of malathion in storage facilities. I will admit here that I have malathion around here for spraying the evergreens with and it did get used in the grain bins four or five years ago before I was brought up to spped on its residual characteristics, we've swtiched to diacamatecous earth for everything like that around the bins.

[wd9]

Wrapper, Health Canada and the PMRA deal with chemical inclusion as a food safety issue. They set the MRL's.

[WRAPper]

I figured youd be telling me that sooner than later , but it still good to discuss it with the industry so they are aware of it.

[WRAPper]

One other thought Health Canada sets the limits but who tests?

[wd9]

The only one that matters is the customer, who are testing more and more. CGC can test in the GRL for around 2600 different molecules with the HPLC.

[melvill]

What's an HPLC?

[wd9]

High Performance Liquid Chromatography aka H Pressure LC. The basic uses, chemical seperation, purification, identification, and quantification. Sorry you asked yet?

Basic use is determine the concentration of a chemical compound (malathion) in a known chemical compound (wheat).

There are three types of chromatographs, gas (which most people have heard of) liquid, and supercritical. Chroma means light, specifically color and graph, well, means to graph

The liquid gets its name from disolving the compound in a solvent like water or alcohol, shoot the stuff thru a tube filled with silicon beads at high pressure and use light and detectors to measure the chemicals (malathion) as they pass thru at different speeds to determine concentration in the known main compound (wheat).

Not exactly how it works, highly simplified, but close enough. I hope Dr. Jim Daun isn't reading this, sorry Jim in advance

Now you know.

[wd9]

I could also add that electrophoresis which is used to determine varieties of grain uses the technique that if you pass electricity thru a gel, add the mooshed up grain to the gel, the individual proteins will migrate at different rates thru the gel and end up looking like a bar code.

Each variety has its own "bar code" picture and is easily identifiable. The HPLC uses the same kind of technique except in the form of gasses moving at different speeds. Ok, I'll stop.

[WRAPper]

You coulda said yah know the thingy they use on CSI to nail the bad guys with ....sheesh go combine your soybeans before it rains tommorrow night.