330-54-1 Diuron

HAs have been issued for bromacil, diuron, and fluometuron no occurrence data are available for tebuthiuron or terbacd (295). Chloroxuron [1982-47-4] fenuronTCA [4482-55-7] andnorea [18530-56-8] also are urea herbicides. 

Urea hydrolysis is frequently observed as the initial reaction for pesticides having urea bonds, such as linuron, diuron, and chlorsulfuron (10) (eq. 14)... 

Although most nonionic organic chemicals are subject to low energy bonding mechanisms, sorption of phenyl- and other substituted-urea pesticides such as diuron to sod or sod components has been attributed to a variety of mechanisms, depending on the sorbent. The mechanisms include hydrophobic interactions, cation bridging, van der Waals forces, and charge-transfer complexes. 

A solvent free, fast and environmentally friendly near infrared-based methodology was developed for the determination and quality control of 11 pesticides in commercially available formulations. This methodology was based on the direct measurement of the diffuse reflectance spectra of solid samples inside glass vials and a multivariate calibration model to determine the active principle concentration in agrochemicals. The proposed PLS model was made using 11 known commercial and 22 doped samples (11 under and 11 over dosed) for calibration and 22 different formulations as the validation set. For Buprofezin, Chlorsulfuron, Cyromazine, Daminozide, Diuron and Iprodione determination, the information in the spectral range between 1618 and 2630 nm of the reflectance spectra was employed. On the other hand, for Bensulfuron, Fenoxycarb, Metalaxyl, Procymidone and Tricyclazole determination, the first order derivative spectra in the range between 1618 and 2630 nm was used. In both cases, a linear remove correction was applied. Mean accuracy errors between 0.5 and 3.1% were obtained for the validation set. 

Dichlorophenyl)-l,1-dimethyl urea (Diuron) [330-54-1] M 233.1. Crystd four times from 95% EtOH [Beck et al. J Am Chem Soc 108 4018 1986]. 

Miscellaneous compounds such as biopesticides (for example. Bacillus thuringiensis and pherhormones), heterocycles (for example, atrazine), pyrethroids (for example, cypermethrin), and urea derivatives (for example, diuron). 

American Society of Safety Engineers (ASSE), 278 American Zinc Association (AZA), 269 AMETREX , ametryn, 12 AMETRON SC , ametryn + diuron, 12 Ametryn, 12... 

E. M. Ean as and S. R. Rissato, Influence of temperature, pressure, modifier and collection mode on superaitical CO2 extraction efficiencies of diuron from sugar cane and orange samples , J. Microcolumn Sep. 10 473-478 (1998). 

J. V. Sancho, C. Hidalgo and P. Hernandez, Direct determination of bromacil and diuron residues in environmental water samples by coupled-column liquid cliromatog-raphy and large-volume injection , 7. Chromatogr. 761 322-326 (1997). 

Pesce S, Fajon C, Bardot C, Bonnemoy F, Portelli C, Bohatier J (2006) Effect of the phenylurea herbicide diuron on natural riverine microbial communities in an experimental study. Aquat Toxicol 78 303... 

Figure 5.2 Electrospray-MS-MS signal response of seven of the pesticides versus eluent flow rate, based on (a) peak area, and (b) peak height , atrazine , simazine , diuron x, isoproturon , chlorfenvinphos , chlorpyrifos O, alachlor. Reprinted from 7. Chromatogr., A, 937, Asperger, A., Efer, J., Koal, T. and Engewald, W., On the signal response of various pesticides in electrospray and atmospheric pressure chemical ionization depending on the flow rate of eluent applied in liquid chromatography-mass spectrometry , 65-72, Copyright (2001), with permission from Elsevier Science.

Ureides (e.g., diuron, linuron) and triazines (e.g., atrazine, simazine, ametryne) all act as inhibitors of photosynthesis and are applied to soil (see Figure 14.1 for structures). They are toxic to seedling weeds, which they can absorb from the soil. Some of them (e.g., simazine) have very low water solubility and, consequently, are persistent and relatively immobile in soil (see Chapter 4, Section 4.3, which also mentions the question of depth selection when these soil-acting herbicides are used for selective weed control). 

These high levels were sporadic and transitory. However, some of them were high enough to have caused phytotoxicity, and more work needs to be done to establish whether herbicides are having adverse effects upon populations of aquatic plants in areas highlighted in this study. It should also be borne in mind that there may have been additive or synergistic effects caused by the combinations of herbicides found in these samples. For example, urea herbicides such as diuron and chlortoluron act upon photosynthesis by a common mechanism, so it seems likely that any effects upon aquatic plants will be additive. Similarly, simazine and atrazine share a common mechanism of action. 

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