Advisory Committee on Health Effects of Endocrine Disruptors
The Supplement II to the Intermediary Report
1.2.4.2

contents  Detailed contents  << prev  next >>

[Notes]

1. If interference is encountered in the LC/MS analysis, use the LC/MS/MS in the MRM mode.
2. The nonyl group in NP isomers is straight or branched. Commercially available standard NP products accordingly consist of either the straight form only or a mixture of various branched forms. The mixed type is preferable for the present purpose, since environmental and biological samples usually give peak patterns corresponding to them. It should be noted, however, the peak patterns of the commercial products may vary among manufacturers, or even among lots from a single manufacturer.
3. The most commonly used substance for correction in the mass spectrometry of NP is straight-chain 4-n-NP (with deuterium and 13C). Since differences in physical and chemical properties of the straight- and branched-chain molecules may present problems in correction, m-OP-d5 is used here, which permits a better correction of the recovery ratio.
4. Repeat the cleaning until a constant operation blank value is attained (usually 3 or 4 times).
5. The "sample" refers here to feeds or litter. For analysis of feed water, use 100 ml sample water and 3 ml hexane only for the same operation.
6. Incorporated water must be removed. Use a Pasteur pipette to separate hexane or freeze down to -20℃ to separate water. Subsequent dehydration by anhydrous sodium sulfate is not needed.
7. Clean the glassware for the evaporator beforehand by distilling acetone under reduced pressure.
8. E.g. Kanto Chemical's Mightysil RP 18 GP, or GL Sciences' ODS-3.
9. The concentration of ammonium acetate is so chosen that the maximum response is obtained in a range of 0 to 2 mM.
10. The definitions of the detection and determination limits follow those given in the Manual for Water Quality Survey Related to Dioxins, Environment Agency, July 1998.

contents  Detailed contents  << prev  next >>