Atrazine determination

Half-Lives of Atrazine Determined by Various Technologies... 

Schlaeppi, J-M., W. Fory, and K. Ramsteiner (1989). Hydroxyatrazine and atrazine determination in soil and water by enzyme-linked immuno-sorbent assay using specific monoclonal antibodies. J. Agric. Food Chem., 37 1532-1538. 

Soil Samples Analysis. Standard soil samples from various locations were used for this study. Aliquots (2 g) were extracted in 20 ml of methanol/water (80/20 v/v). For the competitive ELISA, soil extracts were routinely diluted 1 40 in PBS supplemented with 0.1% Tween-20. The HPLC determination of hydroxyatrazine was done after cleanup of the methanol-extract (17). The samples were injected in a Lichrospher column, SI 60, and the hydroxy-s-triazines were detected at 240 nm (17). The GLC determination of atrazine was performed using a thermoionic (P-N) detector (18). GC-MS for atrazine determination was carried out as described previously (19). 

Fahnrich et al., 2003), and the use of recombinant single-chain antibody (scAb) fragments (Grennan et al., 2003) for atrazine determinations. 

J.-M. Schlaeppi, W. Fory, K.J. Ramsteiner, Hydroxya-trazine and Atrazine Determination in Soil and Water by Enzyme Linked Immunosorbent Assay Using Specific Monoclonal Antibodies , /. Agric. Food Chem., 37, 1532-1538(1989). 

The local restrictions of the use and then the national ban of atrazine determined an adaptation in weed control strategy in Italy during 1987-1991 which can be summarised as follows ... 

There are at least 22 chemical families of organic herbicides. Even a cursory treatment of the chemistry of these materials would be extensive. Herbicides of limited toxicity (Treflan, Atrazine) as well as extremely toxic ones (Paraquat. Dinoseb) are in use in many parts of the world. They range from water soluble to insoluble. The detailed chemistry of each should be determined prior to handling. 

Atrazine is a widely used triazine which can degrade to several products, including deisopropylatrazine (DIA), deethylatrazine (DEA) and hydroxyatrazine (HA). These species are highly polar and their determination by GC requires a derivatiza-tion step. LC methods combined with SPE (off-line or on-line) are therefore the ones which are most commonly used. The LC-LC method proposed in the literature (34) can allow low levels to be detected with a small sample volume. The experimental conditions are shown in Table 13.1. Due to the different polarity between the most... 

K. Grob-Jr and Z. Ei, Coupled reversed-phase liquid cliromatography-capillary gas cliromatography for the determination of atrazine in water , 7. Chromatogr. 473 423-430(1989). 

Figure 15.13 Comprehensive two-dimensional GC chromatogram of a supercritical fluid exti act of spiked human semm. Peak identification is as follows 1, dicamha 2, tiifluralin 3, dicliloran 4, phorate 5, pentachlorophenol 6, atrazine 7, fonofos 8, diazinon 9, cWorothalonil 10, terhufos 11, alachlor 12, matalaxyl 13, malathion 14, metalochlor 15, DCPA 16, captan 17, folpet 18, heptadecanoic acid. Adapted imm Analytical Chemistry, 66, Z. Liu et al., Comprehensive two-dimensional gas chromatography for the fast separation and determination of pesticides exuacted from human senim , pp. 3086-3092, copyright 1994, with pemiission from the American Chemical Society.

Applicators, mixers, loaders, and others who mix, spray, or apply pesticides to crops face potential dermal and/or inhalation exposure when handling bulk quantities of the formulated active ingredients. Although the exposure periods are short and occur only a few times annually, an estimate of this exposure can be obtained by quantifying the excreted polar urinary metabolites. Atrazine is the most studied triazine for potential human exposure purposes, and, therefore, most of the reported methods address the determination of atrazine or atrazine and its metabolites in urine. To a lesser extent, methods are also reported for the analysis of atrazine in blood plasma and serum. 

Supercritical fluid chromatography (SEC) was first reported in 1962, and applications of the technique rapidly increased following the introduction of commercially available instrumentation in the early 1980s due to the ability to determine thermally labile compounds using detection systems more commonly employed with GC. However, few applications of SEC have been published with regard to the determination of triazines. Recently, a chemiluminescence nitrogen detector was used with packed-column SEC and a methanol-modified CO2 mobile phase for the determination of atrazine, simazine, and propazine. Pressure and mobile phase gradients were used to demonstrate the efficacy of fhe fechnique. 

Structurally related compounds may cross-react with the antibody, yielding inaccurate results. In screening for the herbicide alachlor in well water by immunoassay, a number of false positives were reported when compared with gas chromatography (GC) analysis. A metabolite of alachlor was found to be present in the samples and it was subsequently determined that the cross-reactivity by this metabolite accounted for the false-positive results. On the other hand, cross-reactivity by certain structural analogs may not be an issue. For example, in an assay for the herbicide atrazine, cross-reactivity by propazine is 196% because of atrazine and propazine field use... 

E. M. Thurman and C. Batian, Determination of atrazine and atrazine mercapture in drinking water samples and in urine using immunoaffinity SPE with positive ion spray HPLC/MS , Presented at the 15th Symposium on Liquid Chromatography/Mass Spectrometry, Montreux, Switzerland, November 9-10, 1998. 

Pesticides contaminate not only surface water, but also ground water and aquifers. By 1990 in the USSR, 15% of all pesticides used were detected in underground water [29]. Pesticides were detected in 86% of samples of underground water in Ukraine in 1986-87 (including DDT and its metabolites, HCH, dimethoate, phosalone, methyl parathion, malathion, trichlorfon, simazin, atrazine, and prometrin). In actual fact, the number of pesticides was apparently larger, but the laboratory was able to determine the content of only 30 of the 200 pesticides used at that time in Ukraine [29]. In the 1960s, in the Tashkent and Andizhan oblasts of Uzbekistan, the methylmercaptophos content in the water of studied well shafts was, by clearly underestimated data, 0.03 mg/l (MPC was 0.01 mg/l), of DDT was 0.6 mg/l (MPC was 0.1 mg/ I), and of HCH was 0.41 mg/l (MPC was 0.02 mg/l) [A49]. 

Catenacci, G., Maroni, M., Cottica, D., and Pozzoli, L. (1990) Assessment of human exposure to atrazine through the determination of free atrazine in urine, Bulletin of Environmental Contamination and Toxicology, 44 1-7. 

Lucas, A.D., Jones, A.D., Goodrow, M.H., Saiz, S.G., Blewett, C., Seiber, J.N., and Hammock, B.D. (1993) Determination of atrazine metabolites in human urine development of a biomarker of exposure, Chemical Research in Toxicology, 6 107-116. 

J. Pribyl, M. Hepel, J. Halameka, and P. Skladal, Development of piezoelectric immunosensors for competitive and direct determination of atrazine. Sens. Actuat. B 91, 333-341 (2003). 

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