Insecticide in sediment

Bondarenko S, Putt A, Kavanaugh S, Poletika N, Gan J (2006) Time dependence distribution of pyrethroid insecticides in sediments. Environ Toxicol Chem 25 3148-3154... 

Goerlitz and Law [59] determined chlorinated insecticides in sediment and bottom material samples, which also contained polychlorobiphenyls by extracting the sample with acetone and hexane. The combined extracts were passed down an alumina column. The first fraction (containing most of the insecticides and some polychlorinated biphenyls and polychlorinated naphthalenes) was eluted with hexane and treated with mercury to precipitate sulphur. If the polychlorinated hydrocarbons interfered with the subsequent gas chromatographic analysis, further purification on a silica gel column was necessary. 

Reeves and Woodham [83] have described a gas chromatographic method for the determination of Methomyl (S-methyl-N-(methyl carbamoyl)oxy thioacetimidate) insecticide in sediments. The residues were extracted with dichloromethane, and the extracts were purified on a column of Florisil. The purified and concentrated extracts were then examined by gas chromatography. The limits of detection were 0.05mg kg-1 and the recoveries were 91%. 

Leland HV, Bruce WN, Shimp NF. 1973. Chlorinated hydrocarbon insecticides in sediments of southern Lake Michigan. Environ Sci Tech 7 833-838. 

Leland, H.V., WN. Brace, and N.F. Shimp. Chlorinated Hydrocarbon Insecticides in Sediments in Southern Lake Michigan, Environ. Sci. Technol, 7(9) 833-838 (1973). 

Zhou JL, Maskaoui K, Qiu YW, Hong HS, Wang ZD (2001) Polychlorinated biphenyl congeners and organochlorine insecticides in the water column and sediments of Daya Bay, China. Environ Pollut 113(3) 373-384... 

Weston DP, You J, Harwood AD et al (2009) Whole sediment toxicity identification evaluation tools for pyrethroid insecticides in. Temperature manipulation. Environ Toxicol Chem 28 173-180... 

Maund SJ, Hamer MJ, Lane MCG, Farrelly E, Rapley JH, Goggin VM, Gentle WE (2002) Partitioning, bioavailability and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environ Toxicol Chem 21 9-15... 

Lee S, Gan J, Kim JS, Kabashima JN, Crowley DE (2004) Microbial transformation of pyrethroid insecticides in aqueous and sediment phases. Environ Toxicol Chem 23 1-6... 

Amweg EL, Weston DP, You J, Lydy MJ (2006) Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environ Sci Technol 40 1700-1706... 

Hintzen EP, Lydy MJ, Belden JB (2009) Occurrence and potential toxicity of pyrethroids and other insecticides in bed sediments of urban streams in central Texas. Environ Pollut 157 110-116... 

HCH insecticide in agricultural areas of the Mugano-Salyansk land region and also loss or leaching of its residues from recently formed RPA (Galiulin and Galiulina, 1996). Meanwhile the proportion of DDT in the bottom sediments of rivers was DDE + DDD/DDT < 1, that may indicate a relatively little transformation of this insecticide in the present environment (Galiulin, 1994). 

Thus, at present, the input of unused DDT and HCH insecticides in water and bottom sediments of the rivers and reservoirs of the Caspian Sea basin is mainly connected with loss or leaching from old RPA or young LPA. As regards PCBs, their input is mainly related to industrial sources. The high toxicity of POCs for organisms and their persistence in the water and sediments are the principal forms of ecological risk for rivers and the Caspian Sea. The behavior of POCs in the northern part of... 

Sediments have the property of absorbing organic contaminants from water within their bulk (accumulation) and, indeed, it has been shown that the concentration, for example, of some types of insecticide in river sediments is some 10000 times greater than occurs in the surrounding water. 

The average concentration of the BHC andl isomer and a+ isomers, and of DDE and DDT in sediment was found to be 0.010, 0.010, 0.016, 2.11 and 0.70mg kg-1, respectively. These results suggest that chlorinated insecticides, due to their physical and chemical properties, can accumulate and adsorb on to solid particles. 

The procedure described by Suzuki et al. [11, 12], discussed in section 9.1.1.1 for the determination of chlorinated insecticides in soils has also been applied to hexane extracts of river sediments using high-resolution gas chromatography with glass capillary columns. Minimum detectable levels of a-BHC, fs-BHC, -BHC, P-BHC, Heptachlor, Heptachlor epoxide, Aldrin, Dieldrin, Endrin, p,p -DDE, p,p -TDE and p,p -DDT in lOOg samples of bottom sediment were 0.0005, 0.0032, 0.0014, 0.0040, 0.0012, 0.0020, 0.0014, 0.0020, 0.0056, 0.0032, 0.0080 and 0.0120mg kgr1 respectively. 

Wegmann and Hofstee [43] have developed a capillary gas chromatographic method for the determination of organochlorine insecticides in river sediments. Bottom soils from rivers, collected in slow current areas may contain high concentrations of organochlorine insecticides and polychlorobiphenyls. When the current moves more rapidly or benthic animals become more active, these compounds are stirred into the water along with suspended particles and become accessible to organisms that live in the bottom layer. 

The supercritical fluid chromatographic procedure [20] described in section 9.1.1.5 for the determination of organochlorine insecticides in soils has also been applied to river sediments. Snyder et al. [20] compared supercritical fluid extraction with classical sonication and Soxhlet extraction for selected organochlorine insecticides. Samples of sediments extracted with supercritical carbon dioxide modified with 3% methanol at 350atm and 50°C gave =85% recovery of organochlorine insecticides including Dichlorvos, Diazinon, Endrin, Endrin aldehyde, decachlorobiphenyl, p,p -DDT and Mirex. 

Snyder et al. [253] compared supercritical fluid chromatography with classical sonication procedures and Soxhlet extraction for the determination of selected insecticides in soils and sediments. In this procedure the sample was extracted with carbon dioxide modified with 3% methanol at 350atm and 50°C. An excess of 85% recovery of organochlorine and organophosphorus insecticides was achieved. These included Dichlorvos, Diazinon, (diethyl-2-isopropyl-6-methyl 4-pyrimidinyl phosphorothioate), Ronnel (i.e. Fenchlorphos-0,0 dimethyl-0-2,4,5-trichlorophenyl phosphorothioate), Parathion ethyl, Methiadathion, Tetrachlorovinphos (trans-2-chloro-l-(2,4,5 trichlorophenyl) vinylchlorophenyl-O-methyl phenyl phosphoroamidothioate), Endrin, Endrin aldehyde, pp DDT, Mirex and decachlorobiphenyl. 

The microwave assisted extraction for organic compounds including polyaromatic hydrocarbons, phenols and organochlorine insecticides, described in section 11.1.8 [25] has been applied to sediments. The application of supercritical fluid extraction to the determination of various insecticides in soils described in section 11.1.7 [23] has been applied to river sediments. 

Japenga et al. [56] determined polychlorinated biphenyls and chlorinated insecticides in River Elbe estuary sediments by a procedure in which the sediments were pretreated with acetic acid, mixed with silica and Soxhlet-extracted with benzene/hexane. Humic material and elemental sulphur were removed by passing the extract through a chromatographic column containing basic alumina, on which sodium sulphite and sodium hydroxide were adsorbed. Silica fractionation was followed by gas chromatography to analyse chlorinated pesticides, polychlorinated biphenyls and polyaromatic hydrocarbons. Recovery experiments with standard solutions gave recoveries of 90-102%. 

Thus it can be seen that the mean concentration of DAS1 plus DSBP (pg kgy 1) in sediments is some 16000 times greater than it is in the overlying water layer. In the case of BLS this factor exceeds 250000. Similar large factors have been observed in the case of chlorinated insecticides in river waters i.e. bioaccumulation factors of the order of 104. 

Sharom MS, Miles JR, Harris CR, et al. 1980a. Behavior of 12 insecticides in soil and aqueous suspensions of soil and sediment. Water Res 14 1095-1100. 

Neutral Hydrolysis Studies. Investigations of neutral (pH-independent) hydrolysis kinetics in sediment/water systems were conducted for three organophosphorothioate insecticides (chlorpyrifos, diazinon and Ronnel), 4-(p-chlorophenoxy)butyl bromide, benzyl chloride, and hexachlorocyclopentadiene. 

Ramesh, A., Tanabe, S., Murase, H., Subramanian, A.N., Tatsukawa, R., 1991. Distribution and behavior of persistent organochlorine insecticides in paddy soil and sediments in the tropical environment a case study in South India. Environ. Pollut. 74, 293-307. 

To understand the magnitude of contamination of POPs in Vietnam, residue concentrations in air, water, and sediments were compared with those in other countries in Asia-Pacific (Fig. 11.4). Higher contamination of DDTs in Vietnamese coastal environments was recorded, again indicating the extensive use of this insecticide in Vietnam. Interestingly, elevated PCB residues were also observed in water and sediments from Mekong River estuary, southern Vietnam and the levels were comparable to those... 

Natural water (pH 6.0) and sediment (organic content 36%) used in this study were fortified with both the insecticides and subsequently analyzed by the described methods. No response that interfered with the detection of active ingredients was found in any of the untreated controls during incubation. The recoveries for water were 93 4% at 400 ppb and 97 7% at 20 ppb for sediment they were 86 6% and 91 9%, respectively, at the same fortification levels. The minimum detection limit (MDL) for both insecticides was 0.1 ppb in water and 10 ppb in sediment (as sampled). 

Except demethylated fenitrothion, all other metabolites found in water in the earlier study, were also identified in sediments for both the insecticides. Amino-fenitrothion, nitrocresol and monodemethylated aminocarb (MA) were most frequent compared to other metabolites. 

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