Water residue analytical methods

Annex VI to Directive 91/414/EEC concerning the placing of plant protection products on the market. The section concerning residue analytical methods was not fully finalized when the Directive was first adopted. There were no provisions for methods to determine residues from a.i. and relevant metabolites in soil, water, and air. The criteria for foodstuffs partly proved to be not helpful for the practice of assessment (e.g., with regard to reproducibility, ISO 5725 requires validation in at least eight independent laboratories). 

OPPTS 860.1000 Background OPPTS 860.1100 Chemical Identity OPPTS 860.1200 Directions for Use OPPTS 860.1300 Nature of Residue - Plants, Livestock OPPTS 860.1340 Residue Analytical Method OPPTS 860.1360 Multiresidue Method OPPTS 860.1380 Storage Stability Data OPPTS 860.1400 Water, Fish, Irrigated Crops OPPTS 860.1460 Food Handling OPPTS 860.1480 Meat/Milk/Poultry/Eggs OPPTS 860.1500 Crop Field Trials OPPTS 860.1520 Processed Food/Feed OPPTS 860.1550 Proposed Tolerances... 

Thus, organic solvent extraction methods for the extraction of pesticides from water samples can be replaced by the SPE method using Ci8 and PS-2. Ethobenzanid, clomeprop, naproanilide and their acidic metabolites are determined by a multi-residue analytical method using Cig or PS-2 cartridge extraction after acidification of the water samples with hydrochloric acid or other acidic media, followed by HPLC or LC/MS detection. 

A The Multi-residue analytical method is provided for plant, soil and water samples. 

All of the compounds (pyraflufen-ethyl and its metabolites) are converted to E-2 and quantified as the total toxic residue of pyraflufen-ethyl. The conversion to E-2 is carried out by oxidative decomposition with concentrated sulfuric acid. The reaction mixture is extracted with a solvent and subjected to simple cleanup, followed by GC/NPD analysis. This method is rapid and simple compared with the Multi-residue analytical method , and has wide applicability to different varieties of the samples, such as plant materials, soils and water, with only minor adjustment of the analytical method. 

Residue analytical methods for neonicotinoids in crops, soil and water samples have been developed. The basic principle of these methods consists of the following steps extraction of the crop and/or soil samples with acetone or the other organic solvent, cleanup by liquid-liquid partition or column chromatography, and quantitative analysis by high-performance liquid chromatography with ultraviolet detection (HPLC/UV). Simple column cleanup procedures are used to improve the accuracy and sensitivity of these methods. 

Four different types of residue analytical methods of flutolanil and its metabolites are developed for plant (potato and rice), soil and water ... 

Buprofezin and its metabolites, p-OH-buprofezin and BF12, are hydrophobic under neutral conditions. Having the organic base part in their chemical structure, these compounds form water-soluble salts under strongly acidic conditions. The change in solubilities of these compounds influences the cleanup procedure. Four different residue analytical methods have been developed to measure buprofezin and its metabolites in plants (rice, citrus and tomato cucumber, pepper, tomato, squash and eggplant), soil and water ... 

Ocean Data Evaluation System (ODES) Data Submissions Manual QA/QC Guidance for Sampling and Analysis of Sediments Water and Tissue for Dredged Material Evaluations Chemical Evaluations Quality Assurance Plan for the National Pesticide Survey of Drinking Water Wells Analytical Method 2, Chlorinated Pesticides Quality Assurance Project Plan for Analytical Control and Assessment Activities in the National Study of Chemical Residues in Lake Fish Tissue... 

Rodil, R., J.B. Quintana, P. Lopez-Mahia, et al. 2009. Multi-residue analytical method for the determination of emerging pollutants in water by solid-phase extraction and liquid chromatography-tandem mass spectrometry. J. Chromatogr. A. 1216 2958-2969. 

A residue analytical method has been developed for quinomethionate (MORESTAN) in tap water (jLO ) and in various crop produce. In tap water, as low... 

Some indirect method of measuring evaporative loss is needed because of the difficulty of direct measurements. Total amounts in random crop samples at various times after spraying can be measured by residue analytical methods (radioactive tracer or otherwise). The rate of loss so determined is subject to large statistical errors and includes losses by chemical and biochemical reaction and perhaps translocation in the crop as well. Exposure of typical test surfaces treated with some model substance, preferably less volatile than water but sufficiently volatile for simple gravimetric procedure, would seem the most suitable. We will see, however, how successful water is as a model for providing rough estimates. 

A method for the dcicnnination of DAPs in water has been described (Chang etal., 20(X)). This method uses a strong anion exchange disk to isolate DAPs from water and DAPs arc derivatized with methyl iodide in acetonitrile. Capillary GC with FPD was used for determination. A residue analytical method for the determination of DEP... 

Al-Odaini NA, Zakaria MP, Yaziz Ml, Surif S. Multi-residue analytical method for human pharmaceuticals and synthetic hormones in river water and sewage effluents by solid-phase extraction and liquid chromatography—tandem mass spectrometry. J Chromatogr A 2010 1217(44) 6791-806. 

The second analytical method uses a combustion system (O Neil et al. 1994) in place of reaction with BrF,. This method was used for the crocodiles because they were represented by very thin caps of enamel. The enamel was powdered and sieved (20 mg), pretreated in NaOCl to oxidize organic material and then precipitated as silver phosphate. Approximately 10-20 mg of silver phosphate were mixed with powdered graphite in quartz tubes, evacuated and sealed. Combustion at 1,200°C was followed by rapid cooling in water which prevents isotopic fractionation between the CO2 produced and the residual solid in the tube. Analyses of separate aliquots from the same sample typically showed precisions of 0.1%o to 0.4%o with 2 to 4 repetitive analyses even though yields are on the order of 25%. 

Regulation was developed in the 1950s and 1960s to include legal limits (tolerances) for residues on foods and in feeds and, with time, in water and air. Enforcing these regulations required analytical methods of ever-increasing sophistication and... 

For certain naturally occurring nontoxic a.i. an enforcement is not sensible (e.g., lecithin, rape seed oil). Analytical methods for residues in water are not required if the DTgo values of the a.i. and relevant metabolites are less than 3 days (e.g., fosetyl) because, in general, the results from residue analyses are not meaningful if the a.i. is rapidly degraded. 

Chloroacetanilides are soil-applied herbicides used for pre- and early post-emergence control of annual grasses and broadleaf weeds in crops. Representative chloroacetanilide compounds, alachlor, acetochlor, and metolachlor, are extensively used worldwide. Other chloroacetanilides with limited usages include propachlor, bu-tachlor, metazachlor, pretilachlor, and thenylchlor. Public environmental concerns and government regulatory requirements continue to prompt the need for reliable methods to determine residues of these herbicides. There now exist a variety of analytical methods to determine residues of these compounds in crops, animal products, soil, and water. The chemical structures and major crops in which these compounds are used are summarized in Table 1. 

Analytical methods for parent chloroacetanilide herbicides in soil typically involve extraction of the soil with solvent, followed by solid-phase extraction (SPE), and analysis by gas chromatography/electron capture detection (GC/ECD) or gas chromatog-raphy/mass spectrometry (GC/MS). Analytical methods for parent chloroacetanilides in water are similarly based on extraction followed by GC with various detection techniques. Many of the water methods, such as the Environmental Protection Agency (EPA) official methods, are multi-residue methods that include other compound classes in addition to chloroacetanilides. While liquid-liquid partitioning was used initially to extract acetanilides from water samples, SPE using... 

Water samples are amended with isotopically labeled internal standards, acidifled, and purified/concentrated by Cig SPE. The extracts are evaporated to dryness, reconstituted with mobile phase and analyzed by LC/MS/MS. This method determines water residues of flucarbazone-sodium, sulfonic acid, sulfonamide and NODT with an LOQ of 50 ngkg for each analyte. 

Accurate, precise and sensitive analytical methods are important to the collection of data needed for regulatory decisions about pesticide registration. This article describes the various components of analytical method development, validation and implementation that affect the collection of pesticide residue distribution data for regulatory assessment of environmental fate and water quality impacts. Included in this discussion are both the technical needs of analytical methods and the attributes of study design and sample collection needed to develop data that are useful for regulatory purposes. 

The ECL evaluates analytical methods for detecting pesticide residues in the environment to ensure that the methods are suitable for monitoring pesticide residues in soil and water. State, tribal and federal laboratories may access an Index of Environmental Chemistry Methods for a list of available methods. The ECL also provides the State pesticide laboratories with technical and QA support and training in pesticide analytical chemistry. 

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