Pesticides Atrazine

Solid phase extraction Herbicides, pesticides Atrazine [39-41]... 

Major chemical contaminants implicated in food safety include pesticides, herbicides, myeotoxins and antibiotics. These analytes have been targeted by numerous groups developing SPR biosensors. As these analytes are rather small (typical molecular weight < 1,000), inhibition assay has been a preferred detection format. Examples of chemical contaminants detected by SPR biosensors include pesticides atrazine and simazine (detection limits 0.05 ng/ml and 0.1 ng/ml respectively), mycotoxin Fumonisin B1 (detection limit 50 ng/ml ), and antibiotics Sulphamethazine, Sulphadiazine (detection limits 1 ng/ml and 20 ng/ml respectively). 

Forget, J., Pavilion, J.F., Menasria, M.R., and Bocquene, G. Motality and LC50 values for several stages of the marine copepod Tigriopus brevicornis (Muller) exposed to the metals arsenic and cadmium and the pesticides atrazine, carbofuran, dichlorvos, and malathion, Ecotoxlcol. Environ. Saf., 40(3) 239-244, 1998. 

Another example of the potential pernicious effects of pesticides upon human health is the study conducted at the University of Colorado where researchers have found that higher concentrations of four pesticides - atrazine, simazine, alachlor and metolachlor - in groundwater are significantly associated with higher levels of Parkinson disease. For every 10 pg/L increase of pesticide levels in the drinking water, they found that the risk for Parkinson disease increased by 3% and their water samples had pesticide concentrations ranging from 0.0005 to 20 pg/L [38]. 

Illustrative Example 22.3 A Patch of the Pesticide Atrazine Below the Surface of a Lake... 

Analvte PAHs Hydrocarbons Waxes Pesticides Atrazine... 

For all the aforementioned reasons, it is possible to conclude that GEC-based platforms are very suitable for the immunological analysis of food residues according to the food management programs on Hazard Analysis Critical Control Point (HACCP). Procedures 33 and 34 (see in CD accompanying this book) give experimental details on the detection of pesticide atrazine and sulfonamide residues in food samples. 

Triazine pesticides Atrazine, simazine Separated on C-18 reverse phase column and detected by UV at 254 nm mobile phase acetonitrile 0.01 M KH2P04 (65 35)... 

Hardcastle, A., W. Aherne, and V. Marks (1988). A sensitive enhanced luminescent immunoassay for the triazine pesticides atrazine and simazine. J. Biolumin. Chemilumin., 2 209. 

The ways in which microorganisms affect the fate of. y-triazine herbicides and, in a larger sense, all organic pesticides in the environment, are the subject of intense investigation. Among the pesticides, atrazine represents one of the most extensively investigated compounds. 

Chan KH, Chu W. Effect of humic acid on the photolysis of the pesticide atrazine in a surfactant-aided soil-washing system in acidic condition. Water Research 2005 39 2154-66. 

Polybrominated diphenyl ethers Butyl benzyl phthalate Butylbenzyl phthalate Di-n-butlyl phthalate Pesticides Atrazine Carbofuran Toxaphene Endosulfan Lindane... 

Fig. 6 Concentration profiles of the pesticides atrazine and bromacine (upper graphic) as well as 1-chloronaphthalene and related compounds (lower graphic). Both profiles represent contaminations of different emission sources.

At sampling point B the pesticides atrazine and bromacine were detected at elevated concentrations of up to 3.4 pg/L and 5.0 pg/L, respectively. In addition to the major chloronaphthalene contamination their spatial distribution reflects a second, more diffuse emission source for these pollutants upwards of sampling location A (see Fig. 6). Interestingly, these pollutants occurred both in the lower and upper layers of the aquifer. The emission of these substances was obviously not related to the long term impregnation activities but likely to an intensive application of pesticides in the early 90 ies in order to minimise weed growth on the military base. 

Besides the substances related to the impregnation activities, the pesticides atrazine and bromacil were detected and attributed to another contamination source. 

Biodegradation One of the most complex series of mechanisms involving microorganisms, which remains poorly understood. Biodegradation can result in the complete breakdown (neutralisation) of some pollutants or in the transformation of others into daughter compounds (e.g. the pesticide atrazine to diethyl-atrazine) whose toxicity and mobility in the subsurface environment can be enhanced or decreased. 

Pesticides Atrazine Biacore 0.05 ng mL 15 Antibody, inhibition Drinking [22]... 

Richard, J.J., Junk, G. A., Avery, M. J., Nehring, N. L., Fritz,). S. and Svec, H. J. (1975). Analysis of various Iowa waters for selected pesticides atrazine, DDE and dien-drin-1974. Pesticide Monitoring Journal, 9,117-23. 

Triazines and other pesticides Atrazine, acetochlor, alachlor GC-MS, LC-MS (APCI)... 

Ultrasonic extraction of the pesticides atrazine, propham, chlorpropham, diflubenzuron, alpha-cypermethrin, and tetramethrin from soil was optimized in terms of the solvent (acetone), duration of sonication, and number of extraction steps. Comparisons with shake-flask and Soxhlet extractions made using reversed-phase (RP) TLC on C-18 plates showed advantages in extraction efficiencies, simplicity of use, and low-solvent consumption for ultrasonic extraction. ... 

Figure 21-18 shows the resolution of these two ions by an orbitrap mass spectrometer. The spectrum is from a study that resolved, identified, and measured 510 pesticides at parts-per-billion levels in vegetables with a 12-min liquid chromatographic run. The ion CgHisNsCl" from the pesticide atrazine is resolved from the ion C7H14N5O3 from cymoxanil. Errors in the exact mass are 0.000 3 for atrazine and 0.001 0 for cymoxanil. 

Six CMIA mono-immunoassays were developed (cf Table 8.1). The first of these were in the area of clinical biology, with CMIA assays of antiepileptic medications such as carbamazepine [45], phenobarbital [71], diphenylhydantoin [26, 32], and a steroid hormone, cortisol [70]. More recently they have been extended into the environmental area, with assays of pesticides atrazine [44] and chlortoluron [39]. All these assays used polyclonal antibodies. For each of the analytes dilution curves and standard curves were obtained. The curves obtained for carbamazepine, representative of the results for all compounds, are shown in Fig. 8.8. 

We have mostly concentrated on a set of pesticides - atrazine, metolachlor, pendimethalin, and trifluralin - that have been among the most heavily used pesticides in the com-belt region of the United States for many years (4). Atrazine and metolachlor are moderately persistent in tire environment and are relatively soluble in water. Studies have shown that they are two of the most common contaminants of ground and surface water (S). Pendimetiialin and trifliualin are not very mobile in soil (6) however, they are persistent and tend to bioaccumulate (7). 

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