52
River and Stream Sediments
2.4
Organics
2.4.1
Aliphatic and Aromatic Hydrocarbons
Gas chromatography has been used to distinguish between fossil fuels added to
sediments through oil pollution and those hydrocarbons present in low concentrations as natural biogenic products (Blumer and Sass [153], Farrington and Quinn
[154]).
Vowles and Mantoura [143] determined sediment-water partition coefficients and
the high performance liquid chromatography capacity factors for 14 alkylbenzene and
polyaromatic hydrocarbons. The partition coefficients correlated well with the alkylcyano capacity factors, and it was concluded that this phase gave a better indication of
sorption on sediment than either the octanol or octadecylsilane phases.
2.4.2
Polyaromatic Hydrocarbons
Giger and Schnaffner [88] described a glass capillary gas chromatographic method for
the determination of P AHs in lake and river sediments. P AHs are isolated by a
sequence of solvent extraction, gel filtration, and adsorption chromatography and
individual concentrations determined by gas chromatography.
Lopez Avila et al. [730] have described a microwave assisted extraction procedure
for the seperation of polyaromatic hydrocarbons from sediments. Tan [89] devised a
rapid simple sample preparation technique for analysing P AHs in sediments. P AHs
are removed from the sediment by ultrasonic extraction and isolated by solvent
partition and silica gel column chromatography. The sulphur removal step is combined into the ultrasonic extraction procedure. Identification of P AH is carried out by
gas chromatography alone and in conjunction with mass spectrometry. Quantitative
determination is achieved by addition of known amounts of standard compounds
using flame ionization and multiple ion detectors.
Bjorseth et al. [90] described a capillary gas chromatographic method for determining P AHs in sediments. Up to 34 P AHs were identified, some carcinogenic.
Garrigues and Emald [91] give details of a procedure for the determination of
polycyclic aromatic hydrocarbons in sediment samples by high resolution spectrofluorometry in n-alkane matrices.
De Leeuw et al. [92] screened anthropogenic compounds, including PAHs, in
polluted sediments by flash evaporation / pyrolysis-gas chromatography -mass spectrometry. Sediments were homogenized by sonication. Aliquots of samples were then
suspended in methanol and drops applied to a pyrolysis wire, the Curie point of which
was 510°C. The pyrolysis unit was mounted on the detector block of a gas chromatograph at a temperature of 300 °c. Separation was achieved on a fused silica column
coated with CP-SIL5. Flame ionization, flame photometric or electron capture detectors were used to monitor individual compounds which could be identified by mass
spectrometry using 80 eV EI ionization. PAH, halo organics, aliphatic hydrocarbons,
heteroaromatics, elemental sulphur and cyanides were identified.
River and Stream Sediments
2.4
Organics
2.4.1
Aliphatic and Aromatic Hydrocarbons
Gas chromatography has been used to distinguish between fossil fuels added to
sediments through oil pollution and those hydrocarbons present in low concentrations as natural biogenic products (Blumer and Sass [153], Farrington and Quinn
[154]).
Vowles and Mantoura [143] determined sediment-water partition coefficients and
the high performance liquid chromatography capacity factors for 14 alkylbenzene and
polyaromatic hydrocarbons. The partition coefficients correlated well with the alkylcyano capacity factors, and it was concluded that this phase gave a better indication of
sorption on sediment than either the octanol or octadecylsilane phases.
2.4.2
Polyaromatic Hydrocarbons
Giger and Schnaffner [88] described a glass capillary gas chromatographic method for
the determination of P AHs in lake and river sediments. P AHs are isolated by a
sequence of solvent extraction, gel filtration, and adsorption chromatography and
individual concentrations determined by gas chromatography.
Lopez Avila et al. [730] have described a microwave assisted extraction procedure
for the seperation of polyaromatic hydrocarbons from sediments. Tan [89] devised a
rapid simple sample preparation technique for analysing P AHs in sediments. P AHs
are removed from the sediment by ultrasonic extraction and isolated by solvent
partition and silica gel column chromatography. The sulphur removal step is combined into the ultrasonic extraction procedure. Identification of P AH is carried out by
gas chromatography alone and in conjunction with mass spectrometry. Quantitative
determination is achieved by addition of known amounts of standard compounds
using flame ionization and multiple ion detectors.
Bjorseth et al. [90] described a capillary gas chromatographic method for determining P AHs in sediments. Up to 34 P AHs were identified, some carcinogenic.
Garrigues and Emald [91] give details of a procedure for the determination of
polycyclic aromatic hydrocarbons in sediment samples by high resolution spectrofluorometry in n-alkane matrices.
De Leeuw et al. [92] screened anthropogenic compounds, including PAHs, in
polluted sediments by flash evaporation / pyrolysis-gas chromatography -mass spectrometry. Sediments were homogenized by sonication. Aliquots of samples were then
suspended in methanol and drops applied to a pyrolysis wire, the Curie point of which
was 510°C. The pyrolysis unit was mounted on the detector block of a gas chromatograph at a temperature of 300 °c. Separation was achieved on a fused silica column
coated with CP-SIL5. Flame ionization, flame photometric or electron capture detectors were used to monitor individual compounds which could be identified by mass
spectrometry using 80 eV EI ionization. PAH, halo organics, aliphatic hydrocarbons,
heteroaromatics, elemental sulphur and cyanides were identified.