Organic compounds in non-saline sediments 141
employ non-polar columns packed with OV-1, OV-17, OV-101, SE-30, or glass
capillary columns containing similar phases.
Miscellaneous
Farrington and Quinn et al [105] gave details of procedures involving saponification and extraction. Between 32 and 65% of the fatty acids were not released from
sediments by organic solvent extraction.
Mendoza et al [106] determined carboxylic acid compounds in a 5 mol L
−1 lacustrine sediment core taken in Leman Lake, Unbound and tightly bound compounds
were not converted from one form to another. The abundance profiles below 30 cm
were not only similar but showed no decreasing trend, suggesting a common original
in three forms. The presence of unsubstantiated monounsaturated acids in the C20–
C32 range suggested a possible origin for long chain fatty acids other than from higher
plants. Nothing was known of the origins of (omega-1)-hydroxy acids longer than
C20, or those of 2-methylnonacosanoic acid.
Raman and Hopke et al [107] have applied ion chromatography to the analysis
of water soluble short-chain organic acids in ambient particulate matter. Studies have
shown that the inclusion of water-soluble short-chain (WSSC) organic acids in source
apportionment using positive matrix factorisation (PMF) resulted in an improvement
in the model’s ability to resolve sources, and in understanding secondary particle formation. In the United States, numerous network samplers are operational. Quartz-fibre
filters for thermal optical carbon analysis have been collected over a period of years as a
part of these sampling campaigns on a routine basis. However, only a small portion of
these filters are used for the carbon analysis. Thus, there is the potential to utilise these
samples to enhance organic speciation for subsequent use in source apportionment.
In this work, an ion-chromatographic method was developed to identify and quantify
the water soluble short chain organic acids present in fine particulate matters (PM 2.5 ).
Samples collected to measure the concentrations of particles (PM 2.5 ) in southwestern (Stockton) and northern (Potsdam) New York, USA from November 2002 to
June 2004 were used in this study. Acetic, formic, propionic, oxalic, and malonic acids
were successfully identified. The identified species accounted for 5–15% of the organic
matter mass and this enhances the knowledge of the atmospheric organic-matter constituents. Oxalic acid was the most abundant species of Potsdam and Stockton with
median concentrations of 17.71 ng m
−3 and 92 ng m
−3 , respectively. Acetic and formic
acids were present in the Potsdam source at median concentrations of 12.54 ng m
−3 and
14.48 ng m
−3 , while at Stockton they were present at 57.58 ng m
−3 and 51.54 ng m
−3
respectively. The median concentration values for all acids at Stockton were higher
than Potsdam. These observations are consistent with a study conducted in a semiurban location, Schenectady, New York. At both sites, propionic and malonic acids
were found in much lower concentrations when compared with the other acids. The
concentration time series of various acids and seasonal variations in individual acids
are discussed. The co-variance of acetic and formic acids is also outlined.
6.2.3 Aldehydes and ketones
Liggo and McLaren et al [108] optimised a method for the determination of
volatile and semi-volatile aldehydes and ketones in ambient particulate matter.
employ non-polar columns packed with OV-1, OV-17, OV-101, SE-30, or glass
capillary columns containing similar phases.
Miscellaneous
Farrington and Quinn et al [105] gave details of procedures involving saponification and extraction. Between 32 and 65% of the fatty acids were not released from
sediments by organic solvent extraction.
Mendoza et al [106] determined carboxylic acid compounds in a 5 mol L
−1 lacustrine sediment core taken in Leman Lake, Unbound and tightly bound compounds
were not converted from one form to another. The abundance profiles below 30 cm
were not only similar but showed no decreasing trend, suggesting a common original
in three forms. The presence of unsubstantiated monounsaturated acids in the C20–
C32 range suggested a possible origin for long chain fatty acids other than from higher
plants. Nothing was known of the origins of (omega-1)-hydroxy acids longer than
C20, or those of 2-methylnonacosanoic acid.
Raman and Hopke et al [107] have applied ion chromatography to the analysis
of water soluble short-chain organic acids in ambient particulate matter. Studies have
shown that the inclusion of water-soluble short-chain (WSSC) organic acids in source
apportionment using positive matrix factorisation (PMF) resulted in an improvement
in the model’s ability to resolve sources, and in understanding secondary particle formation. In the United States, numerous network samplers are operational. Quartz-fibre
filters for thermal optical carbon analysis have been collected over a period of years as a
part of these sampling campaigns on a routine basis. However, only a small portion of
these filters are used for the carbon analysis. Thus, there is the potential to utilise these
samples to enhance organic speciation for subsequent use in source apportionment.
In this work, an ion-chromatographic method was developed to identify and quantify
the water soluble short chain organic acids present in fine particulate matters (PM 2.5 ).
Samples collected to measure the concentrations of particles (PM 2.5 ) in southwestern (Stockton) and northern (Potsdam) New York, USA from November 2002 to
June 2004 were used in this study. Acetic, formic, propionic, oxalic, and malonic acids
were successfully identified. The identified species accounted for 5–15% of the organic
matter mass and this enhances the knowledge of the atmospheric organic-matter constituents. Oxalic acid was the most abundant species of Potsdam and Stockton with
median concentrations of 17.71 ng m
−3 and 92 ng m
−3 , respectively. Acetic and formic
acids were present in the Potsdam source at median concentrations of 12.54 ng m
−3 and
14.48 ng m
−3 , while at Stockton they were present at 57.58 ng m
−3 and 51.54 ng m
−3
respectively. The median concentration values for all acids at Stockton were higher
than Potsdam. These observations are consistent with a study conducted in a semiurban location, Schenectady, New York. At both sites, propionic and malonic acids
were found in much lower concentrations when compared with the other acids. The
concentration time series of various acids and seasonal variations in individual acids
are discussed. The co-variance of acetic and formic acids is also outlined.
6.2.3 Aldehydes and ketones
Liggo and McLaren et al [108] optimised a method for the determination of
volatile and semi-volatile aldehydes and ketones in ambient particulate matter.