AWWA WQTC60573

Atmospheric pressure ionization (API) LC/MS and LC/MS/MS technology has had awide range of applications in environmental analysis. These include the identification,confirmation, and quantification of polar disinfection byproducts (DBPs), pesticides, herbicidesand other contaminants in water samples. The improved LC/MS and LC/MS/MStechniques have made it possible to directly analyze aqueous samples with a sensitivity of subpartper billion to low part per billion levels for many organic chemicals. Direct aqueousanalysis has four obvious advantages. These include: significantly reduced analytical costsassociated with sample collection, shipping, storage, and extraction; improved accuracy andprecision of analytical results; improved turn-around time of analytical results; and,reduction of matrix effects because the samples are not preconcentrated.This paper summarizes several applications of LC/MS and LC/MS/MS technology fordirect aqueous analysis of polar regulated and unregulated contaminants in finished drinkingwater and source water. The contaminants studied include perchlorate, ethylenethiourea(ETU), 2,6-dichlorobenzamide (BAM), and a number of selected pesticides. The methoddetection limits (MDLs) were calculated as a product of the standard deviation of seven replicateanalyses and the student's t value with a 99% confidence level and n-1 degrees of freedom.The method accuracy (mean recovery) and precision (relative standard deviation, RSD) weredetermined by measuring 4-7 replicate laboratory fortified blanks (LFBs). The two analyticalsystems used were a Waters 2690 LC equipped with a ZMD detector and a Waters 2695 LCequipped with a Quattro micro API detector (Waters, Milford, MA). Includes 12 references, tables.

Product Details

Edition:

Vol. - No.

Published:

11/15/2004

Number of Pages:

5

File Size:

1 file , 290 KB