(MRL) Maximum Residue Levels for Pesticides in or on food and feed of plant and animal

On the regulation of (MRL) Maximum Residue Levels for Pesticides in or on food and feed of plant and animal:

I think European Union and Japan really did a good job on that.

It is really dilemma to the using of the Pesticides: Some "Environmental-concern" people always want to Pesticides free in all everything. Some"Profit-oriented" always try to use all high efficient Pesticides without caring the impact.

As for me, European Union and Japan: from the regulation view, they are good example for USA and China.

http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2008:058:0001:0398:EN:PDF

( LC-MS/MS) Contamination of Detergents/Surfactant

Which detergent used in the Lab now? Look like the contamination of the detergent/surfactant which was used for the glassware.

Did you notice the m/z different of all the peaks in the mass spectrum?

Tips:
Calculated the most dominant five peaks in the mass spectrum.
305,349,393,437,481,525,569 -> there is 44 different in m/z.
Also checked the less dominant peaks:
333, 377, 421, 465, 509,553 -> there is also 44 different in m/z.
The m/a difference between the first line and second line is 16, look like [M+Na]+, for the second like [M+K]+.

As the m/z = 44.
I think that may be the PEG （polyethylene glycol）:-[-CH2-CH2-O-]-n .
The monomer of PEG is C2H4O ( m/z is 44).
That are the evidences why I doubt that is from the contamination of detergents/surfactant.