Pesticides Propazine

The use of solar powered systems for destruction of a mixture of pesticides in well water including dichloroaniline, benzopyran, atrazine, propazine, alachlor, prometryn, bromacil and cyanobenzoate has been achieved [124], Variable efficiencies for the decomposition of these compounds was observed with over 90% of dichloroaniline destroyed in 10 h compared to 50% of propazine in the same period. In general for most of the pesticides examined the half life time for the process in the 100 ppb concentration range was less than 1 h. 

Triazines such as atrazine, propazine or simazine, are widely used herbicides. Currently, the determination of atrazine in water and soil samples is mainly done by GLC (1,2) or HPLC (3-5). However, these procedures require cumbersome cleanup steps which could be avoided by using immunoassays as an alternative approach to residue analysis. Such immunochemical determination based on competitive binding of herbicides or pesticides to an antibody (6,7), has been described recently for s-... 

This range of compounds consists of the many chemicals that are used to control pests worldwide. Target species include insect, animal, or plant species. Examples of the hundred or so pesticides that have been studied to determine their removal during drinking water treatment processes include -5-triazines (atrazine, simazine, cyanazine, propazine), lindane, DDT, 2, 4-D, atachlor, metolachlor, asulam, hymexazol, methomyl, imidacloprid, carbaryl, linuron, thiobencarb, and diquat. 

Pesticide Simazine Propazine Atrazine Prometon Ametryn Prometryn... 

The triazines make up the final general class of herbicides. This class includes the most prevalent pesticide in use for over two decades, atrazine. It also includes prometon, propazine, and simazine. Acute poisoning with the triazines results in anorexia, depression, and muscular symptomology. The oral doses in rodents required for toxic effects are greater than 1.74 gAg, again making these compounds extremely safe. There is no evidence of toxicity from field usage reports. 

A number of other structural types of pesticides are/may be also of carcinogenicity concern. These include the biphenyl ethers, hydrazides, substituted phenylureas and substituted amino-s-triazines as represented by nitrofen (NCI Technical Report No. 26), daminozide (NCI Technical Report No. 83), monuron (NTP Technical Report No. 266) and propazine (see ref. 29),... 

When excess acid is added to the system, H ions (actually hydro-nium ions) compete for adsorption sites (Equation 6) and displace the pesticide cations back into solution as shown in Figure 9 where the pH decreases from 4 to 1 for prometone. Again the process depends upon the pKa of the compound for example, propazine cations are not released until the pH decreases from 2 to 1 (Figure 9). When strongly acid exchange resins were used, the s-triazine cations released were in the hydroxy form, having been hydrolyzed at the resin surfaces (57). 

Like most other classes of pesticides and herbicides, the degree of toxicity of triazines has been found to vary with compounds. Thus, the toxicity may not be solely attributed to the triazine ring. For example, while substances such as atrazine, metribuzin, and cyanazine are moderately toxic by all routes of exposure, compounds such as prometryn and propazine have a very low order of toxicity. However, no cases of human poisonings have been reported. A few selected triazine herbicides are discussed individually in the following sections. 

ESI-LC-MS was used to characterise and differentiate the triazine herbicides atrazine, terbuthylazine, propazine and prometryn. In source CID spectra were reported. Low-energy CID of [M-tH] ions confirmed the characteristic fragmentation patterns and permitted distinction of isomeric triazines [555]. Results obtained from ESI-LC-MS and APCI-LC-MS and MS/MS for the analysis of polar triazine pesticides in water confirmed a better performance of APCI compared to ESI (cf. 15.3.3.2 APCI, triazines) [325]. 

SPME coupled to ESI-LC-MS was used to determine the triazine pesticides simazine, atrazine, propazine and prometryn in leachates obtained from soil samples. SPME compared with other extraction methods showed less interference from the matrix compound [513]. 

Pesticides (carbendazim, simazine, atrazine, propazine and ametryn, dimon and Unuron, carbaryl and propoxur), in drinking water and carrot... 

Simultaneous analysis was carried out on multi-component pesticide residues in various food products. Results obtained indicated excellent reproducibility (10% at 5 ppb) and linearity with better than 0.995 in the range ofO.l-lOOppb (0.1-100 pg/pL injected). Figure 4.54 shows as example the calibration curve for propazine at 0.1-100 ppb with a corresponding chromatogram at 1 ppb, showing excellent reproducibility R = 0.9998). 

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