3.4- Dichloroaniline degradation

Willberg DM, PS Lang, RH Hochemer, A Kratel, MR Hoffmann (1996) Degradation of 4-chlorophenol, 3,4-dichloroaniline, and 2,4,6-trinitrotoluene in an electrohydraulic discharge reactor. Environ Sci Technol 30 2526-2534. 

A sediment-water system was used to study the partition and the degradation of C-labeled 4-nitrophenol and 3,4-dichloroaniline (Heim et al. 1994). The results clearly illustrated the importance of water-to-sediment partitioning, and that a substantial fraction of the substrates existed in the form of nonextractable residues. 

Crescenzi et al. developed a multi-residue method for pesticides including propanil in drinking water, river water and groundwater based on SPE and LC/MS detection. The recoveries of the pesticides by this method were >80%. Santos etal. developed an on-line SPE method followed by LC/PAD and LC/MS detection in a simultaneous method for anilides and two degradation products (4-chloro-2-methylphenol and 2,4-dichlorophenol) of acidic herbicides in estuarine water samples. To determine the major degradation product of propanil, 3,4-dichloroaniline, the positive ion mode is needed for atmospheric pressure chemical ionization mass spectrometry (APCI/MS) detection. The LOD of 3,4-dichloroaniline by APCI/MS was 0.1-0.02 ng mL for 50-mL water samples. 

Biological. Degradation of radiolabeled diuron (20 ppm) was not observed after 2 wk of culturing with Fusarium and two unidentified microorganisms. After 80 d, only 3.5% of the applied amount evolved as C02 (Lopez and Kirkwood, 1974). In 8 wk, <20% of diuron in soil (60 ppm) was detoxified (Corbin and Upchurch, 1967). 3,4-Dichloroaniline was reported as a minor degradation product of diuron in water (Drinking Water Health Advisory, 1989) and soils (Duke et al, 1991). 

Under aerobic conditions, mixed cultures isolated from pond water and sediment degraded diuron (10 pg/mL) to 3-(3-chlorophenyl)-l,l-dimethylurea (CPDU), 3,4-dichloroaniline, 3 (3,4-dichlorophenyl)-l-methylurea, carbon dioxide, and a monodemethylated product. The extent of biodegradation varied with time, glycerol concentration, and microbial population. The degradation half-life was <70 d at 30 °C (Ellis and Camper, 1982). 

Thom and Agg (1975) reported that diuron is amenable to biological treatment with acclimation. Soil Several degradation pathways were reported. The major products and reaction pathways include formation of l-methyl-3-(3,4-dichlorophenyl)urea and 3-(3,4-dichlorophenyl)urea via Wdealkylation, a 6-hydroxy derivative via ring hydroxylation, and formation of 3,4-dichloroaniline, 3,4-dichloronitroaniline, and 3,4-dichloronitrobenzene via hydrolysis and oxidation (Geissbiihler et al, 1975). 

Surface Water. 2,6-Dichloroaniline, 2-chloro-2, 6 -diethylacetanilide, and 2-hydroxy-2, 6 -dieth-ylacetanilide were reported as possible degradation products of alachlor that were identified in the Mississippi River and its tributaries (Pereira and Rostad, 1990). 

CASRN 36734-19-7 molecular formula C13H13CI2N3O3 FW 330.17 Soil. Readily degrades in soil (half-life 20-160 d) releasing carbon dioxide and dichloroaniline (Hartley and Kidd, 1987 Walker, 1987). The rate of degradation increases with repeated applications of this fungicide. In a clay loam, the half-life was 1 wk. After the second and third applications, the half-lives were 5 and 2 d, respectively (Walker et al., 1986). 

Soil. Linuron degraded in soil forming the common metabolite 3,4-dichloroaniline (Duke et al, 1991). In an aerobic, biologically active, organic-rich, pond sediment, linuron was converted to the intermediate 3-(3-chlorophenyl)-l-methoxymethylurea. This compound degraded to unidentified compounds (Stepp et ah, 1985). 

Soil. Propanil degrades in soil forming 3,4-dichloroaniline (Bartha, 1968, 1971 Bartha and Pramer, 1970 Chisaka and Kearney, 1970 Duke et al., 1991) which degrades via microbial peroxidases to 3,3, 4,4 -tetrachlorazobenzene (Bartha and Pramer, 1967 Bartha, 1968 Chisaka and Kearney, 1970), 3,3, 4,4 -tetrachloroazooxybenzene (Bartha and Pramer, 1970), 4 (3,4-dichloroanilo)-3,3, 4,4 -tetrachloroazobenzene (Linke and Bartha, 1970), and l,3-bis(3,4-dichloro-phenyl)triazine (Plimmer et al., 1970), propionic acid, carbon dioxide, and unidentified products (Chisaka and Kearney, 1970). Evidence suggests that 3,3, 4,4 -tetrachloroazobenzene reacted with... 

Another common laboratory reaction of amines is diazotization to provide unstable and highly reactive diazonium salts. Plimmer et al (14) have isolated an aromatic triazene (XV) from soil containing 3,4-dichloroaniline (XIV) and presented evidence that it is formed by "natural diazotization of the aniline followed by coupling with a second amine molecule (Fig. 5). If this is true— that the natural nitrite commonly found in soil and water can bring about diazotization—a new dimension must be added to both the natural mechanisms of herbicide degradation and the generation of new series of potentially dangerous transformation products. 

Polcaro, A.M., Mascia, M., Palmas, S. and Vacca, A. (2004) Electrochemical degradation of diuron and dichloroaniline at BDD electrode. Electrochim. Acta 49, 649-656. 

Polcaro, A.M., Mascia, M., Palmas, S. and Vacca, A. (2004) Electrochemical degradation of diuron and dichloroaniline at BDD electrode. Electrochim. Acta, 49,649-656 Polcaro, A.M., Vacca, A., Mascia, M. and Palmas, S. (2005) Oxidation at boron doped diamond electrodes An effective method to mineralise triazines. Electrochim. Acta 50,1841-1847 Posada, D., Betancourt, P., Liendo, F. and Brito, J.L. (2006) Catalytic wet air oxidation of aqueous solutions of substituted phenols. Catal. Lett. 106, 81-88 Rajeshwar, K. and Ibanez, J. (1997) Fundamentals and Applications in Pollution Abatement, Academic, New York, NY... 

Soil. Metabolism occurs by loss of the vinyl group, cleavage of the 5-membered ring and eventual formation of 3, 5,-dichloroaniline. Soil degradation takes place with half-lives of several weeks, and mainly leads to the formation of bound residues... 

Cabras, E, Diana, E, Meloni, M., Firisi, F.M., and Pirisi, R. (1983). Reversed-phase high-performance liquid chromatography of pesticides. Analysis of Vinclozolin, Iprodione, Procymidone, Dichlozolinate and their degradation product 3,5-dichloroaniline on white must and wine extracts,/. Chromatogr., 256,176-181. 

---