Organics
105
tion, absorption and infrared spectra, distribution of molecular weight, trace metal
content, and adsorption at a hanging mercury drop electrode. Humic acids from the
marine environments had a higher nitrogen content than the estuarine humic acid.
The most humified material was that isolated from deep sea sediment in the Norwegian Sea. Fulvic acid had a lower carbon content and a higher oxygen content than the
humic acids, and was more hydrophilic.
Hayase [310] characterised fulvic acid from sediment collected from Tokyo Bay by
reversed phase liquid chromatography. Sedimentary fulvic acid exhibited increasing
hydrophilic character with increasing molecular weight. The method used was effective for the hydrophobic /hydrophilic characterization of humic substances.
4.4.6
Chlorophenols
Xie [311] determined trace amounts of chlorophenols and chloroguaiacols in marine
sediments collected off the Swedish coast. The compounds were desorbed from
sediment surfaces by a mixture of acetic anhydride and hexane, after buffering with
0.1 mol 1-1 sodium carbonate. The optimal pH was achieved by a 1 : 4 ratio of buffer to
acetic anhydride. The acetylated extracts were analysed by glass capillary gas chromatography with electron capture detection. The recoveries, at the Ilg kg- 1 level, ranged
from 85-100 % with standard deviations of 4-11 %.
4.4.7
Chlorinated Insecticides
Picer et al. [312] described a method for measuring the radioactivity oflabelled DDT
contaminated sediments in relatively large volumes of water, using a liquid scintillation spectrometer. Various marine sediments, limestone, and quartz in sea water were
investigated. External standard ratios and counting efficiencies of the systems investigated were obtained, as was the relation of efficiency factor to external standard ratios
for each system studied.
4.4.8
Polychlorinated Biphenyls
A method has been described [313] for separating polychlorinated biphenyls from
chlorinated insecticides. This procedure involves adsorption chromatography on
alumina and charcoal columns, elution with increasing fractional amounts of hexane
on alumina columns, and with acetone-diethyl ether on charcoal columns. The polychlorinated biphenyls and chlorinated pesticides are then determined by gas chromatography-mass spectrometry on the separate eluates without interference.
Jensen et al. [314] have described a method applicable to marine sediments for the
determination of polychlorobiphenyls and organochlorine insecticides, in which the
sample is extracted with acetone, then n-hexane together with 1 % aqueous ammonium chloride. The extracts are then concentrated for purification with concentrated
sulphuric acid and aqueous sodium sulphate in the presence of tetrabutyl ammonium
sulphate, and finally analysed by gas chromatography.
105
tion, absorption and infrared spectra, distribution of molecular weight, trace metal
content, and adsorption at a hanging mercury drop electrode. Humic acids from the
marine environments had a higher nitrogen content than the estuarine humic acid.
The most humified material was that isolated from deep sea sediment in the Norwegian Sea. Fulvic acid had a lower carbon content and a higher oxygen content than the
humic acids, and was more hydrophilic.
Hayase [310] characterised fulvic acid from sediment collected from Tokyo Bay by
reversed phase liquid chromatography. Sedimentary fulvic acid exhibited increasing
hydrophilic character with increasing molecular weight. The method used was effective for the hydrophobic /hydrophilic characterization of humic substances.
4.4.6
Chlorophenols
Xie [311] determined trace amounts of chlorophenols and chloroguaiacols in marine
sediments collected off the Swedish coast. The compounds were desorbed from
sediment surfaces by a mixture of acetic anhydride and hexane, after buffering with
0.1 mol 1-1 sodium carbonate. The optimal pH was achieved by a 1 : 4 ratio of buffer to
acetic anhydride. The acetylated extracts were analysed by glass capillary gas chromatography with electron capture detection. The recoveries, at the Ilg kg- 1 level, ranged
from 85-100 % with standard deviations of 4-11 %.
4.4.7
Chlorinated Insecticides
Picer et al. [312] described a method for measuring the radioactivity oflabelled DDT
contaminated sediments in relatively large volumes of water, using a liquid scintillation spectrometer. Various marine sediments, limestone, and quartz in sea water were
investigated. External standard ratios and counting efficiencies of the systems investigated were obtained, as was the relation of efficiency factor to external standard ratios
for each system studied.
4.4.8
Polychlorinated Biphenyls
A method has been described [313] for separating polychlorinated biphenyls from
chlorinated insecticides. This procedure involves adsorption chromatography on
alumina and charcoal columns, elution with increasing fractional amounts of hexane
on alumina columns, and with acetone-diethyl ether on charcoal columns. The polychlorinated biphenyls and chlorinated pesticides are then determined by gas chromatography-mass spectrometry on the separate eluates without interference.
Jensen et al. [314] have described a method applicable to marine sediments for the
determination of polychlorobiphenyls and organochlorine insecticides, in which the
sample is extracted with acetone, then n-hexane together with 1 % aqueous ammonium chloride. The extracts are then concentrated for purification with concentrated
sulphuric acid and aqueous sodium sulphate in the presence of tetrabutyl ammonium
sulphate, and finally analysed by gas chromatography.