Leeder Analytical provides testing and advice for environmental forensics and identification of unknown compounds. They can identify faecal sterols in water, groundwater, and sediment samples to detect sewage contamination and pollutants from leaking sewers. Faecal sterols come from the digestion of animals and humans and provide a fingerprint to identify the source of faecal pollution. Leeder Analytical uses gas chromatography-mass spectrometry to identify and quantify target sterols and compounds at part per trillion levels to determine the presence and source of faecal contamination in samples.

1. Leeder Analytical provides specialist testing and expert advice in a wide range of areas
including environmental forensics, auditor support, identification of unknown chemical
compounds, chemical residues and impurities.
Sewerage Contamination of Water,
Groundwater and Sediments
Identification of faecal sterols in water,
groundwater and sediment samples can
be useful in identifying the presence of
sewage contamination and sometime for
the identification of other pollutants. For
example a leaking sewer can sometimes
impact an aquifer with industrial pollut-
ants such as chlorinated solvents. Faecal
sterols as biomarkers provide a valuable
tool in the investigation of the sources
and fate of faecal contamination in the
environmental. Identical of faecal contami-
nation in waterways, marine environment
and groundwater may be an indicator of
run-off, leaking septic tanks and/or leaking
sewers. The data obtained can be useful
in pin pointing source/s of faecal pollution
in our environment.
Faecal Sterols
Faecal sterols are excreted by animals and
humans as by-products of digestion of
dietary sterols.
The particular distribution of sterols found
in faecal matter is influenced by factors
such as diet, intestinal microflora and the
animal’s ability to synthesise its own ste-
rols. The combination of these factors de-
termines ‘the sterol fingerprint’. The most
commonly known faecal sterol, copros-
tanol, is produced in the digestive tract
of humans by microbial hydrogenation of
cholesterol. By drawing on the differences
in the sterol profile of humans and ani-
mals, it is possible identify to the presence
of and also distinguish the source of faecal
contamination. Many compounds ingest-
ed, included pharmaceutical’s in our diet
are excreted in addition to the sterol profile
compounds such as caffeine, isobuprofen,
trichlosan and aspirin (acetylsalicylic acid)
are also examined for as an indication of
sewerage input.
Methodology
Water samples and soil samples are
solvent extracted. The solvent extracts are
then concentrated and derivatised. The ex-
tracts are then analysed by high resolution
capillary gas chromatography-mass spec-
trometry (GC/MS) to identify and quantitate
the target compounds. The relative ratio of
the sterols is calculated and the presence
of target compounds is used to determine
the presence and source of faecal contam-
ination. Leeder Analytical have developed
a sensitive method that is able to detect
these compounds at ng/L (ppt) level.
Sample Requirement
Two 500ml brown glass bottles are
required for each sample location. The
samples should be acid preserved, chilled
on ice and shipped to Leeder Analytical for
analysis.
Leeder
Analytical
Leeder
Analytical
33 Steane St,
Fairfield, VIC, 3078
t 03 9481 4167
f 03 9489 0710
abn 31 142 075 956
e Enquiries@leeder-analytical.com
Cerberus Global trading as Leeder Analytical
Please contact us to discuss your projects requirements.