ABSTRACT
The synthesis and determination of persistent dicarboxylic metabolites of alkylphenol polyethoxylates (NPEOs), carboxyalkyl phenoxy ethoxy carboxylates (CAPECs), are investigated. The synthesized CAPECs have three and four carbon atoms and a carboxyl group in the alkyl chain side, and a carboxymethoxy acid group in its para-position (expressed as CA(3)P1EC and CA(4)P1EC in their abbreviation). The synthesis was successfully accomplished via a four-step reaction sequence that started from 4-fluoroanisole. After propylation by a propanol/acetyl chloride procedure, the derivatives of synthesized CA(3)P1EC and CA(4)P1EC were separated and identified by GC-MS with electron impact ionization (EI). The most abundant characteristic ions were produced by benzylic cleavages of carboxyalkyl chain to yield [M-87](+), corresponding to ions of m/z 235 for CA(3)P1EC and m/z 249 for CA(4)P1EC. Recoveries of synthesized CA(3)P1EC and CA(4)P1EC in various spiked water samples ranged from 82 to 92% with relative standard deviations (RSD) lesser than 7%. The limits of quantitation (LOQ) of CA(3)P1EC and CA(4)P1EC were estimated to be 0.005 and 0.01 microg/l in 100ml of water samples, respectively. The concentrations of CA(4)P1EC residues were detected in the aquatic environment ranging from n.d. to 3.24 microg/l. The results show that the synthesized CA(4)P1EC has been successfully applied to more accurately determine the concentrations of CA(4)P1EC residues in water samples.
