Herbicidal residues

Ana.lytica.1 Methods. Since 1984, dramatic technical advances have been made in the analysis of trace organic chemicals in the environment. Indeed, these advances have been largely responsible for the increased pubUc and governmental awareness of the wide distribution of herbicides in the environment. The abiUty to detect herbicides at ppb and ppt levels has resulted in the discovery of trace herbicide residues in many unexpected and unwanted areas. The realization that herbicides are being transported throughout the environment, albeit at extremely low levels, has caused much pubUc and governmental concern. However, the pubUc health implications remain unclear. 

The efficient recovery of volatile nitrosamines from frankfurters, followed by gc with chemiluminescence detection, has been described (133). Recoveries ranged from 84.3 to 104.8% for samples spiked at the 20 ppb level. Methods for herbicide residues and other contaminants that may also relate to food have been discussed. Inorganic elements in food can be deterrnined by atomic absorption (AA) methods. These methods have been extensively reviewed. Table 8 Hsts methods for the analysis of elements in foods (134). 

Bromocresol green (3.8...5.4) aliphatic carboxylic acids[103,187 — 204] triiodobenzoic acid [205], derivatives of barbituric acid [206] amphetamine derivatives [207, 208] phenazones, morazone [209] alkaloids [91, 209] nephopam [210] phenyramidol metabolites [211] diethylalkylacetamide derivatives [212] zipeprol (Mirsol) [213] thalidomide and hydrolysis products [214] cyclohexylamine derivatives [215] herbicide residues [216]... 

Dinitroaniline herbicides show minimal plant systematic translocation properties with the majority of the absorbed residues in the root tissues. Metabolites identified include traces of Al-dealkylation, alkyl and aryl hydroxylation and nitro reduction products. Low levels of dinitroaniline herbicide residues have been reported in raw agricultural commodities according to Good Agricultural Practice. 

The amount of dinitroaniline herbicide residue (7 ,mgkg ) in the sample is calculated with the following equation ... 

Dinitroaniline herbicides have low soil mobility potential. Herbicide residues in the treated field are usually incorporated into the upper layers of the soil mainly as unextractable bound residue therefore, the movement of dinitroaniline herbicides from soil to the water compartment is minimal. Run-off is the principal route, which could lead to the contamination of surface waters. Residue methods were developed to measure the parent concentration in water samples. 

Because of the limited root uptake and slow rate of systemic translocation, the diphenyl ether herbicide residues detected in the aerial plant portion are low. 

Diphenyl ethers in the soil are absorbed by roots with limited translocation generally to the foliage. Low levels of herbicide residues can be expected when the compound is used in accordance with good agricultural practice. The parent diphenyl ether compound is defined as the residue of analytical and regulatory concern. 

Miyake et al reported an ELISA method for the determination of pesticide residues in the aquatic environment. The polyclonal antibody and three monoclonal antibodies of acifluorfen were prepared by immunization of rabbits and mice with acifluorfen-bovine serum albumin conjugates. The polyclonal antibody reacted with acifluorfen at concentrations of 1.5-800 mg L , while the monoclonal antibodies reacted with acifluorfen at concentrations of 1.5-144 mg L . Among three monoclonal antibodies, AF 75-144 reacted with chlornitrofen, which did not react with the other two antibodies. It seems that the ELISA method is effective for the determination of herbicide residues in the aquatic environment. 

Bartley, T.R. 1967. Progress report on evaluation of copper for aquatic weed control and herbicide residues on irrigation systems. U.S. Bur. Reclam. Rep. No. WC-32. 58 pp. 

Spengler and Jumar [90] used a spectrophotometric method and thin layer chromatography to determine carbamate and urea herbicide residues in sediments. The sample is extracted with acetone, the extract is evaporated in vacuo at 40°C and the residue is hydrolysed with sulphuric acid. The solution is made alkaline with 15% aqueous sodium hydroxide and the liberated aniline (or substituted aniline) is steam distilled and collected in hydrochloric acid. The amine is diazotized and coupled with thymol, the solution is cleaned up on a column of MN 2100 cellulose power and the azo-dye is determined spectrophotometrically at 440nm (465nm for the dye derived from 3-chloro- or 3.4-dichloroaniline) with correction for the extinction of a reagent blank. 

Smith and Fitzpatrick [252] have also described a thin layer method for the detection in water and soil of herbicide residues, including Atrazine, Barban, Diuron, Linuron, Monuron, Simazine, Trifluralin, Bromoxynil, Dalapon, Dicamba, MCPB, Mecoprop, Dicloram, 2,4-D, 2,4-DB, Dichloroprop, 2,4,5-T, and 2,3,6-trichlorobenzoic acid. 

Byast, T.H., Cotterill, E.G. and Hance, R.J. (1977) Methods for the Analysis of Herbicide Residues, 2nd edn. Technical Report, Agricultural Research Council, Weed Research Organization, Yamton, UK, No. 15. 

Potassium, iron, phosphorus, and other elements in soil formaldehyde residue in insulation, cellophane, and other materials pesticide and herbicide residue in plants. 

Determination of preservatives (sorbic and benzoic acid, parabens) in food products Determination of phenylurea herbicide residues in vegetables and vegetable processed food Separation of flavonoids from extracts of Adinandra nitida leaves... 

De Rossi, A., and Desiderio, C. (2005). Application of reversed phase short end-capillary electrochromatography to herbicides residues analysis. Chromatographia 61, 271—275. 

Kaufman, D.D. and Kearney, PC. Microbial degradation of s-triazine herbicides. Residue Rev., 32 235-265, 1970. 

Lange, A. H., Fischer, B., Humphrey, W., Seyman, W., andBaghott, K. Herbicide residues in California agricultural soils, Calif. Agric, 22 2-4, 1968. 

Yaron B, Gerstl Z (1983) Herbicide residues in soils following point source application. Pesticide chemistry, human welfare and the environment. Pergamon Press, Oxford, pp 207-212 Yaron B, Bielorai H, Kliger L (1974) Fate of insecticides in an irrigated field—azinphosmethyl and tetradifon cases. J Environ Qual 3 413 17... 

In 1979 and 1983 (9,10). The data Indicated that although penetration of herbicide and TCDD had occurred throughout the soil profiles sampled (8 cm Increments down to 32 cm), the bulk of the chemicals remained near the surface. Data from the microbial analyses of soil samples collected from the Herbicide Storage Areas confirmed that proliferation of certain microflora occurred under high levels of herbicide residue. 

The addition of coconut charcoal Increases persistence of phenoxy herbicide residues, especially residues of 2,4,5-T. 

Important for increasing the effectiveness of water-quality protection policies are the assessment of herbicides, nitrates, and antibiotics in water resources, the development of immunochemical techniques to measure herbicide residues, and the application of enzyme-linked immunosorbent assays. 

JJ Kikland. Trace analysis by programmed temperature gas chromatography. Simultaneous determination of monuron and diuron herbicide residues. Anal Chem 34 428-433, 1962. 

G Voss, H Geissbiiler. Methodological aspects of urea herbicide residue analysis. In AS Tahory, ed. Methods in Residue Analysis. New York Gordon and Breach Science Publishers, 1971, pp 525-536. 

JA Guth, G Voss. Automated colorimetric procedure for the determination of total and unchanged urea herbicide residues in soil. Weed Res 11 111-119, 1971. 

S. Nawaz, Pesticides and herbicides, Residue determination. In B. Caballero, L. Trugo and P.M. Finglas (Eds.), Encyclopedia of Food Science and Nutrition, Academic Press, 2003, pp. 4487-4493. 

Coastal estuary wetlands are susceptible to arsenic contamination because of hurricanes or other storms. Sediments deposited in 2005 by Hurricane Katrina in New Orleans, Louisiana, USA, were often contaminated with arsenic that exceeded human health standards (Cobb et al., 2006). The arsenic may have originated from runoff containing lawn herbicide residues and the leachates of wood treated with CCA preservatives (Cobb et al, 2006), 4576. 

Yip [405] reported that the binding of the soil particles and organic matter with the herbicide residues prevented the complete extraction of them with an organic solvent. Upchurch and Mason [406] found that the extent of adsorption of herbicides is highly dependent on the type of organic matter and clay as well as on the amounts of their constituents. 

Chlorinated [407,408] and 2,4-dinitrophenoxy acid herbicides [409] have been determined. liquid chromatography particle beam mass spectrometry has been used as an analytical finish [408]. Crescenzi et al. [410] evaluated the feasibility of selectively and rapidly extracting herbicide residues in soils by hot water and collecting analytes with a Carbograph 4 solid-phase extraction cartridge set on-line with the extraction cell. Phenoxy acid herbicides and those non-acidic and acidic herbicides that are often used in combination with phenoxy acids were selected for this study. Five soil samples were... 

Kloskowski, R., and Ftihr, F. (1987). Aged and bound herbicide residues in soil and their bioavailability. J. Environ. Sci. Health B22, 623-642. 

Wicks, G.A., C.R. Fenster, and O.C. Burnside (1969). Herbicide residue in soil when applied to sorghum in a winter wheat-sorghum-fallow rotation. Agron. J., 61 721-724. 

Forestry uses of triazines involve only one or two applications on the same site during a rotation, which may span 30-70 years or more. Under these conditions, accumulation of herbicide residues and potential leaching and runoff hazards are greatly diminished. 

Qiao, X., R. During., and H. Hummell (1991). Triazine herbicide residues in soil by gradient HPLC-UV analysis Quantitative and simultaneous trace determination of seven pollutants at the ppb level. Mededelingen van de Faculteit Landbouwwetenschappen Rijkuniversiteit. Gent, 56(3a) 949-959. 

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