Determination of Acetanilide Degradates in Ground and Surface Waters by Direct Aqueous Injection LC/MS/MS

A multianalyte method is reported for the determination of atrazine, simazine, propazine, and their respective dealkylated chlorotriazine metabolites; ametryn and prometryn and their respective dealkylated thiomethyltriazine metabolites; and S-metolachlor and its ethanesulfonic and oxanilic acid degradates in deionized, ground, surface, and finished drinking water. Water samples are analyzed using direct aqueous injection (DAI) liquid chromatography-electrospray ionization/mass spectrometry/mass spectrometry (LC-ESI/MS/MS). No preanalysis sample manipulation is required other than transfer of a small portion of sample to an injection vial. The lower limit of the method validation is 0.050 microg/L (ppb) for all analytes except 2,4-diamino-6-chloro- s-triazine (didealkylatrazine, DDA, or G-28273). For this compound the LLMV is 0.50 microg/L (ppb). The overall mean procedural recoveries (and percent relative standard deviations) for all water types for all analytes ranged from 95 to 101% (4.5-11%). The method validation was conducted under U.S. EPA FIFRA Good Laboratory Practice Guidelines 40 CFR 160.

Section: Introductionmentioning

confidence: 99%

Direct Aqueous Injection LC−ESI/MS/MS Analysis of Water for 11 Chloro- and Thiomethyltriazines and Metolachlor and Its Ethanesulfonic and Oxanilic Acid Degradates

Huang

Mayer

Yokley

2008

“…Direct injection liquid chromatography/electrospray ionization-mass spectrometry/mass spectrometry (LC/ESI-MS/MS) has been successfully applied to the analysis of a wide range of compounds in various sample matrices including opioids and cocaine (15) and alkyl phosphates (16) in urine, propamocarb (17) and N-methyl carbamate pesticides (18) in wine, and organophosphorus pesticides in vegetable extracts (19). Several applications to the analysis of pesticides in water have been reported and include the determination of dimethyl tetrachloroterephthalate (20), 4-chloro-2-methylphenoxyacetic acid (21), various organophosphorus pesticides (22), carbamates, thiocarbamates, and phenylureas (23), and acetanilide degradates (24). In this work, direct aqueous injection LC/ESI-MS/MS is used to quantify five triazine compounds in water with minimal sample manipulation prior to injection.…”

Section: Introductionmentioning

confidence: 99%

Direct Aqueous Injection Liquid Chromatography/Electrospray Ionization-Mass Spectrometry/Mass Spectrometry Analysis of Water for Atrazine, Simazine, and Their Chlorotriazine Metabolites

Huang

Mayer

Yokley

et al. 2006

A method is reported for the determination of atrazine, simazine, and their respective dealkylated chlorotriazine metabolites in ground, surface, and finished drinking water. Water samples are diluted 1:4 in an injection vial prior to analysis using liquid chromatography/electrospray ionization-mass spectrometry/mass spectrometry (LC/ESI-MS/MS). The lower limit of method validation is 0.10 microg/L (ppb) for 2-chloro-4-(ethylamino)-6-isopropylamino)-s-triazine (atrazine, G-30027), 2-chloro-4, 6-(diethylamino)-s-triazine (simazine, G-27692), 2-amino-4-chloro-6-(isopropylamino)-s-triazine (deethylatrazine, DEA, or G-30033), 2-amino-4-chloro-6-(ethylamino)-s-triazine (deisopropylatrazine, DIA, or G-28279), and 2,4-diamino-6-chloro-s-triazine (didealkylatrazine, DDA, or G-28273). The overall mean procedural recoveries (and % relative standard deviations) for atrazine, simazine, DEA, DIA, and DDA are 98 (4.4), 102 (3.6), 99 (4.8), 103 (4.0), and 109% (4.8%), respectively, in finished drinking water; 108 (2.7), 104 (5.4), 113 (4.5), 111 (5.2), and 105% (5.3%), respectively, in groundwater; and 96 (6.9), 103 (4.2), 102 (4.4), 102 (5.2), and 102% (8.2%), respectively, in surface water. The method validation was conducted under U.S. EPA FIFRA Good Laboratory Practice Guidelines 40 CFR 160.

“…In a field-disappearance study, the observed disappearance half-life was 8 days and alachlor ESA was formed at a fast rate. Alachlor ESA is a more polar compound than alachlor and has been found more frequently and at higher concentrations than the parent herbicide in groundwater because of leaching and in surface water because of agricultural runoff (16)(17)(18)(19). The presence of alachlor ESA in waters can create toxicological effects toward soil and aquatic organisms (20), and it is necessary to survey both the parent compound and metabolite to understand the environmental fate of this herbicide in soil and prevent groundwater contamination.…”

Section: Introductionmentioning

confidence: 99%

Degradation of Alachlor in Natural and Sludge-Amended Soils, Studied by Gas and Liquid Chromatography Coupled to Mass Spectrometry (GC−MS and HPLC−MS)

Rodríguez‐Cruz

Lacorte

2005

Alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide] is an herbicide used worldwide. The relative rates of disappearance of alachlor, the formation kinetics of alachlor ethane sulfonic acid (ESA), and the formation of other degradation products in two different soils (a soil with natural organic matter and a sludge-amended soil) has been studied. For such a purpose, soil samples were spiked with alachlor at 2.5 mg kg(-1), concentration generally applied in agricultural soils, and were submitted to sunlight, simulating natural field conditions. Extracts were analyzed by GC-MS and HPLC-MS in scan mode. A good correlation was observed between both techniques, and HPLC-MS allowed the determination of two eluting peaks corresponding to the two stereoisomeric forms of alachlor ESA. Degradation of alachlor in the two soils followed first-order kinetics. Half-life in the natural soil was 4.2 +/- 0.1 days, and half-life in the sludge-amended soil was 5.8 +/- 0.8 days. The higher half-life observed in the sludge-amended soil was attributed to the higher sorption of alachlor to this soil compared to the natural soil. The degradation of alachlor in both soils gave rise to the production of alachlor ESA. Its concentration increased during the incubation period, and after 27 days, its concentration was about 0.59 mg kg(-1) in the natural soil and 0.37 mg kg(-1) in the sludge-amended soil. The other two alachlor transformation products were identified using GC-MS, and the abundance of these degradation products increased while alachlor was degraded.