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Environmental Fate Data for Miscellaneous Compounds
Published in John H. Montgomery, Thomas Roy Crompton, Environmental Chemicals Desk Reference, 2017
John H. Montgomery, Thomas Roy Crompton
Plant. In rice plants, propanil is rapidly hydrolyzed via an aryl acylamidase enzyme isolated by Still (1968), forming the nonphototoxic compounds (Ashton and Monaco, 1991) 3,4-dichloroaniline, propionic acid (Matsunaka, 1969; Menn and Still, 1977; Hatzios, 1991), and a 3′,4′-dichloroaniline–lignin complex. This complex was identified as a metabolite of N-(3,4-dichlorophenyl)glucosylamine, a 3,4-dichloroaniline saccharide conjugate, and a 3,4-dichloroaniline sugar derivative. In a rice field soil under anaerobic conditions, however, propanil underwent amide hydrolysis and dechlorination at the para-position forming 3,4-dichloroaniline and 3-chloroaniline (Pettigrew et al., 1985). In addition, propanil may degrade indirectly via an initial oxidation step, resulting in the formation of 3,4-dichlorolacetanilide which hydrolyzes to 3,4-dichloroaniline and lactic acid (Hatzios, 1991). In an earlier study, four metabolites were identified in rice plants, two of which were positively identified as 3,4-dichloroaniline and N-(3,4-dichlorophenyl)glucosylamine (Still, 1968).
Toxic Metals and Agrochemicals in Soils in Malaysia: Current Problems and Mitigation Plans
Published in P.M. Huang, I.K. Iskandar, M. Chino, T.B. Goh, P.H. Hsu, D.W. Oscarson, L.M. Shuman, Soils and Groundwater Pollution and Remediation, 2020
Y. M. Khanif, I. C. Fauziah, J. Shamshuddin
Laboratory and field studies were also conducted by Ooi and Lo (1990) to determine the acute toxicity of 11 herbicides common to paddy field fish in Malaysia. The studies indicated that herbicide bensulfuron, 2, 4-D, metsulfuron, and quinclorac have low toxicity (LC50 > 10 ppm) to sepat siam (Trichogaster pectoralis) and catfish (Claria batrachu), while butachlor, molinate, oxadiazon, pretilachlor, propanil, and thiobencarb are moderately toxic (LC50 0.5 to 10 ppm), but fenoxaprop is highly toxic (LC50 < 0.5 ppm). However, field studies showed bensulfuron, 2, 4-D, fenoxaprop, oxadiazon, and propanil at double the effective rates for weed control were safe to the fish.
State of the art of the environmental behaviour and removal techniques of the endocrine disruptor 3,4-dichloroaniline
Published in Journal of Environmental Science and Health, Part A, 2018
Andrea Luca Tasca, Ashleigh Fletcher
Biological studies have also shown microbial consortia to be successful in the removal of propanil and 3,4-DCA from repeated batch suspended cell cultures,[105] as well as in biofilm reactors for agricultural wastewater treatment.[106] In the latter case, the porous volcanic stone tezontle was used as a support for a biofilm in a continuous process able to degrade propanil and metabolic intermediates at rates of up to 24.9 mg L−1 h−1, without the need for co-substrates. Pseudomonas sp., Acinetobacter calcoaceticus, Rhodococcus sp., Xanthomonas sp. and Kokuria strains can also grow individually in 3,4-DCA, while other strains found in the biofilm, not able to degrade propanil metabolites directly, are probably involved in the metabolization of herbicide adjuvants or in the maintenance of biofilm integrity. Resultantly, the removal of chloroanilines from sewage treatment plant streams could be improved by promoting the growth of indigenous bacterial communities, and through the introduction of adapted laboratory strains. The addition of readily degradable aniline and non-toxic haloaromatics may, respectively, improve the breakdown of chloroanilines and the chlorocatechol potential.[94]