Degradation estuarine water

Walker WW, Cripe CR, Pritchard PH, et al. 1988. Biological and abiotic degradation of xenobiotic compounds in in vitro estuarine water and sediment/water systems. Chemosphere 17 2255-2270. 

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. 

Lee, R.F., Ryan, C. (1979) Microbial degradation of organochlorine compounds in estuarine waters and sediments. In Proceedings of the Workshop of Microbial Degradation of Pollutants in Marine Environments. EPA-600/9-79-012. Washington, D.C. 

Walker et al. [84] examined several methods and solvents for use in the extraction of petroleum hydrocarbons from estuarine water and sediments, during an in situ study of petroleum degradation in sea water. The use of... 

Jones, T.W., W.M. Kemp, J.C. Stevenson, and J.C. Means. 1982. Degradation of atrazine in estuarine water/sed-iment systems and soils. Jour. Environ. Qual. 11 632-638. 

Synthetic pyrethroids now account for at least 30% of the world insecticide market and are rapidly replacing other agricultural chemicals for control of insect pests. Fenvalerate is one of the more widely used synthetic pyrethroid insecticides. It is derived from a combination of a-cyano-3-phenoxybenzyl alcohol and a-isopropyl phenylacetate ester. Technical fenvalerate is a mixture of four optical isomers, each occurring in equal amounts but with different efficacies against insect pests. Fenvalerate does not usually persist in the environment for >10 weeks, and it does not accumulate readily in the biosphere. Time for 50% loss (Tb 1/2) in fenvalerate-exposed amphibians, birds, and mammals was 6 to 14 h for reptiles, terrestrial insects, aquatic snails, and fish it was >14 h to <2 days and for various species of crop plants, it was 2 to 28 days. Fenvalerate degradation in water is due primarily to photoactivity, and in soils to microbial activity. Half-time persistence in nonbiological materials is variable, but may range up to 6 days in freshwater, 34 days in seawater, 6 weeks in estuarine sediments, and 9 weeks in soils. 

To assess the relative importance of the volatilisation removal process of APs from estuarine water, Van Ry et al. constructed a box model to estimate the input and removal fluxes for the Hudson estuary. Inputs of NPs to the bay are advection by the Hudson river and air-water exchange (atmospheric deposition, absorption). Removal processes are advection out, volatilisation, sedimentation and biodegradation. Most of these processes could be estimated only the biodegradation rate was obtained indirectly by closing the mass balance. The calculations reveal that volatilisation is the most important removal process from the estuary, accounting for 37% of the removal. Degradation and advection out of the estuary account for 24 and 29% of the total removal. However, the actual importance of degradation is quite uncertain, as no real environmental data were used to quantify this process. The residence time of NP in the Hudson estuary, as calculated from the box model, is 9 days, while the residence time of the water in the estuary is 35 days [16]. 

To further investigate the recalcitrance of A9PE2C, the water at the end of the experiments was mixed with freshly collected estuarine water. In three of the five experiments, degradation of the residual A9PE2C started at day 20 and concentrations had dropped by 50% after 32 days. 

Surface Water. In raw river water (pH 7.3 to 8.0), 90% degraded within 2 wk, presumably by biological activity (Eichelberger and Lichtenberg, 1971). In estuarine water, the half-life of malathion ranged from 4.4 to 4.9 d (Lacorte et al, 1995). 

In a cranberry soil pretreated with 4-nitrophenol, parathion was rapidly mineralized to carbon dioxide by indigenous microorganisms (Ferris and Lichtenstein, 1980). The half-lives of parathion (10 ppm) in a nonsterile sandy loam and a nonsterile organic soil were <1 and 1.5 wk, respectively (Miles et al, 1979). Walker (1976b) reported that 16 to 23% of parathion added to both sterile and nonsterile estuarine water was degraded after incubation in the dark for 40 d. 

The dye-sensitized photodecomposition of atrazine was studied in aqueous, aerated solutions. When the solution was irradiated in sunlight for several hours, 2-chloro-4-(isopropyl-amino)-6-amino-s-triazine and 2-chloro-4-(isopropylamino)-6-acetamido-s-triazine formed in yields of 70 and 7%, respectively (Rejto et al, 1983). Continued irradiation of the solution led to the formation of 2-chloro-4,6-diamino-s-triazine which eventually degraded to unidentified products. Hydroxyatrazine was the major intermediate compound formed when atrazine (100 mg/L) in both oxygenated estuarine water (Jones, 1982 Mansour et ah, 1989) and estuarine sediments were exposed to sunlight. The rate of degradation was slightly greater in water (half-life 3-12 d) than in sediments (half-life 1-4 wk) (Jones et al., 1982). 

Lacorte, S., Lartiges, S.B., Garrigues, P., andBarceld, D. Degradation of organophosphorus pesticides and their transformation products in estuarine waters, Environ. Sci. Technol, 29(2) 431-438, 1995. 

Atrazlne degraded in estuarine water with a half-life of 3-12 days, in two estuarine sediments with half-lives of 15 and 20 days, and in two agricultural soils with half-lives of 330 and 385 days it was concluded that degradation is slower in agricultural soils than in estuarine systems (51). In two different soils under lab conditions, where the pHs were 4.8 and 6.5, respective half-lives of 53 days and 113 days were found (52). 

Hwang, H-M., Hodson, R. E. Lee, R. F. (1986). Degradation of phenol and chlorophenols by sunlight and microbes in estuarine water. Environmental Science and Technology, 20, 1002-7. 

Pritchard, P.H., C.R. Cripe, W.W. Walker, J.C. Spain, and A.W. Bourquin, 1987. Biotic and abiotic degradation rates of methyl parathion in freshwater and estuarine water and sediment samples. Chemosphere 16, 1509-1520. 

Lee, R.F., Ryan, C. (1979) Microbial degradation of organochlorine compounds in estuarine waters and sediments. In Proceedings of the Workshop of Microbial Degradation of Pollutants in Marine Environments. EPA-600/9-79-012. Washington D.C. Lee, S., Pardue, J.H., Moe, W.M., Valsaraj, K.T. (2003) Mineralization of desorption-resistant 1,4-dichlorobenzene in wetland soils. Environ. Toxicol. Chem. 22, 2312-2322. 

Finally, Forward et al.149 provide further evidence for a role for plant carbohydrates as larval inducers. They showed that humic acids either from a commercial source or extracted from estuarine water (the latter presumably complexes derived from the degradation of plant carbohydrates) enhanced the rate of metamorphosis of blue crab (Callinectes sapidus) larvae.149... 

Walker et al. [114] examined several methods and solvents for use in the extraction of petroleum hydrocarbons from estuarine water and sediments, during an in situ study of petroleum degradation in sea water. The use of hexane, benzene and chloroform as solvents is discussed and compared, and quantitative and qualitative differences were determined by analysis using low-resolution computerised mass spectrometry. Using these data, and data obtained following the total recovery of petroleum hydrocarbons, it is concluded that benzene or benzene-methanol azeotrope are the most effective solvents. 

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