matrix-matched standard calibration

[s2008]

Hello All,

From the literature, I know that matrix-matched calibration will be a good method for compensating matrix effect in the LC-MS/MS or GC-MS analysis. However , the paper [ Anastassiades, M., S. J. Lehotay, D. Stajnbaher and F. J. Schenck (2003): ] mentioned that FDA and EPA did not like this way. It states as following:

“ According to European guidelines, matrix-matched standards must be used unless it is shown that the matrix does not have an effect in the analysis. In the U.S.A, regulatory policies of the FDA and EPA do not permit the use of matrix-matched calibration standards for pesticides enforcement purposes, even though numerous studies have demonstrated that significant errors can occur when matrix effects are not taken into account . “
I just wonder whether
(1) FDA and EPA change the policy (above literature published in 2003)?
(2) could somebody tell me the FDA or EPA latest guideline to handling matrix effect?

Thanks lot

[randy]

For EPA air methods, a "matrix spike" is generally prepared and analyzed. This is an aliquot of a previously analyzed sample and is prepared by the method of known standard addition. The matrix spike results will aid in determining if matrix effects are significant, but they are not usually used to compensate for the matrix biases.