EPA Method 535.0 Measurement of Chloracetanilide and Other Acetamide Herbicide Degradates in Drinking Water by Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS)

This application brief demonstrates the measurement of chloracetanilide and other acetamide herbicide degradates in drinking water by Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS).

Chloroacetanillide and acetamide herbicides are widely used in the United States for the control of broadleaf and annual weeds on crops, such as corn and soybeans. These herbicides are thought to be degraded by microbial action to the oxanilic acid (OA) and ethanesulfonic acid (ESA) metabolites of the parent compounds. The OA and ESA metabolites are more water soluble and therefore more mobile than the parent herbicides. Several studies by the United States Geological Survey (USGS) and others have reported higher occurrences of the OA and ESA metabolites than the parent herbicides in both ground and surface water. The United States Environmental Protection Agency (US EPA) Method 535 was developed for the determination of OA and ESA metabolites of alachlor, acetochlor, metochlor, propachlor, flufenacet, and dimetheamide in drinking water. The European Union (EU) regulation regarding drinking water (EC Directive 98/83/EC), provides a general rule for pesticides and metabolites. This regulation limits the maximum admissible concentration (MAC) at 0.1 ppb for each individual component, with the total concentration not to exceed 0.5 ppb.

Sample Preparation

A 250 mL water sample is extracted using a graphitized carbon SPE cartridge, dried and made up to 1 mL with 5 mM ammonium acetate.

Eluent Preparation

A: 5 mM aqueous ammonium acetate

B: Methanol

Related Documents

• Acetamide Herbicides and Metabolites in Drinking Water - WA31763.10
• Analysis of Chloroacetanilide and Acetamide Herbicide Degradates in Drinking Water by UPLC-MS/MS - 720001999EN