Isotope Analysis Service

Welcome to the CSIRO Isotope Analysis Service, Adelaide, South Australia. 

The service provides stable isotope analyses for hydrological, environmental, biological and medical purposes. It also has a comprehensive carbon dating capability, CFC laboratory and analytical facilities for ²²²Rn and ²²⁶Ra.  The isotope laboratory has special expertise in groundwater hydrology and use of carbon and nitrogen isotopes. 

Established in 1984, the service now undertakes approximately 2500 analyses per year for over 80 customers, 20% of which are based outside Australia. 

The major strengths of this service are: 

• Commercial service established for 14 years
• Laboratory established for 28 years
• Continuing analytical development 
• Reliable turnaround 
• International reputation as consultant to IAEA and extensive collaboration with universities 
• Back-up consulting service available

Stable isotopes 

Deuterium (d²H) and Oxygen-18 (d ¹⁸O) 

Deuterium and oxygen-18 compositions of water samples provide a useful tool for investigating hydrological processes in surface and groundwater systems. In groundwater, the ²H and ¹⁸O signature gives an indication of the climatic conditions under which recharge took place. In surface water/catchment studies, stable isotopes have been used to estimate retention times and the hydrologic response of catchments to rainfall. 

The Service also supports research work in which stable isotopes are used to identify the different sources of water taken up by plants. In addition it is involved in the use of single (deuterated) and double (¹⁸O and deuterated) labelled water in estimation of energy metabolism and fat-free mass in humans, mammals and reptiles. 

Carbon-13 (d¹³C) and Nitrogen-15 (d¹⁵N) 

d¹³C for carbonate material may indicate whether it is of marine or terrestrial origin while d¹³C for dissolved inorganic carbon (DIC), when used with ¹⁴C analysis, provides a methodology to correct groundwater ages for water-rock interaction.  The d¹³C composition of soil organic matter may indicate vegetation type or changes in vegetation and, at enriched levels, is often used to study carbon turnover in soils. In marine and freshwater studies, the d¹³C signature may be used to identify the proportion of energy obtained by consumers such as fish from different sources (phytoplankton vs terrestrial vegetation). 

d¹⁵N in legumes can be used to reflect the proportion of contribution from soil inorganic N and symbiotically fixed N while in plant and soil, it can be used in tracer studies of soil N transformations.

[Back to Contents]  

Carbon dating 

Established in 1976 primarily for dating water samples, the laboratory began commercial carbon dating services in 1984. An older benzene-based system has been replaced by a  procedure involving the direct absorption of CO₂ into Carbosorb for counting via a low level Quantulus Liquid Scintillation Counter (DA). This procedure has proven to be a more reliable, cost effective alternative to benzene synthesis. At this stage 70% of samples analysed for ¹⁴C are water samples. Charcoal, wood, cellulose and shell are also dated. A ¹³C/¹²C analysis is provided for each sample submitted for ¹⁴C at no additional charge. If insufficient carbon is available for analysis using the direct absorption technique, or if better precision is required, samples are able to be analysed using Accelerator Mass Spectrometry (AMS). For this service, samples should be sent directly to us for preparation. The accelerator mass spectrometry is carried out at the Rafter Radiocarbon Laboratory in New Zealand. 

With extensive experience in radiocarbon analysis of groundwater samples from regional aquifers throughout Australia, the IAS is now the principal provider of this service in Australia and a major provider for the Asian-Pacific region. 

Chlorofluorocarbon (CFC) analysis 

The presence of man-made CFCs in the atmosphere for the last 50 years means that these compounds are now in groundwater in quantities that largely reflect the presence and proportions of recent recharge waters. Measurement of CFC-11 and CFC-12 allows groundwater ages to be determined since 1960 with a precision of approximately 3 years. 

Current work includes support for groundwater research in the Clare Valley of South Australia, an important wine-producing area heavily dependent on local fractured rock aquifers for irrigation water. 

The specialised nature of sample collection for CFC analysis means that this service requires prior arrangements with clients. We are currently involved in developing techniques to make sampling the CFC analysis more user-friendly and hence more readily available as an investigation tool. 

[Back to Contents]  

²²²Rn and ²²⁶Ra 

²²²Rn and ²²⁶Ra form part of the decay chain for uranium bearing minerals. They are often found in higher concentrations in groundwater than in surface water because the groundwater usually has more contact with soil than the surface water. By utilising this, ²²²Rn and ²²⁶Ra are often used to identify areas of input of groundwater into streams and rivers. Determination of dissolved ²²²Rn and ²²⁶Ra in groundwater is reasonably simple, requiring only 14 ml water samples, while 1 litre samples are required for surface water. The present detection limit is 0.3 Becquerels per litre (1 Becquerel = 1 dist per sec). 

[Back to Contents]

Service specifications 

Facilities 

• 3 stable isotope gas ratio mass spectrometers 
• 2 on-line combustion systems - continuous flow and trace gas analysis 
• 2 Wallac Quantulus Liquid Scintillation Counters 
• CFC analysis by purge and trap gas chromotography 
• Automated equilibration system for ²H and ¹⁸O analysis of water.

Average turnaround

Precision and sensitivity 

The Service can detect isotope concentrations to the following level of precision: 

Sample requirements 

Prospective clients should note the following minimum amounts of sample material required by the laboratory for analysis. If it is not possible to collect enough material for analysis, please contact the laboratory prior to sampling to discuss alternative options. In any case, direct contact with the laboratory before submitting samples is essential to ensure appropriate procedure for sample collection and treatment.

Please do NOT add Mecuric Chloride to water when collecting samples as this causes problems with some analyses.   

* The amount of water required to provide sufficient carbon (as DIC) for ¹⁴C analysis is primarily a function of the pH and [HCO^-₃] of the water sample. Please ask laboratory staff to send an information sheet prior to sampling. 

Many of these analyses may also be performed on gas samples (eg air, soil gas). Please contact the laboratory if interested. 

[Back to Contents]

Price list 

Printable price list also available (PDF, 15 kB)

* samples collected in triplicate
** price includes distillation to extract water for analysis
* **price includes gravimetric water content

All prices are in Australian dollars. Prices are inclusive of GST or, if samples submitted from outside Australia, inclusive of quarantine charges. Priority service (shorter turnaround time) is available for a 25% surcharge. Please contact Fred Leaney or Megan LeFournour for further information. 

Staff 

Mr Fred Leaney General isotopic services and ¹⁴C dating 
Dr Andrew Herczeg Specialist consulting services 
Mr John Dighton²²²Rn and ²²⁶Ra, isotope methodology 
Dr Peter Cook CFC dating 
Ms Megan LeFournour Technical Officer 
Ms Michelle Caputo Technical Officer 

For further information contact: 
Mr Fred Leaney 
CSIRO Land and Water
Private Bag No. 2
Glen Osmond SA 5064
Australia
tel: +61-8-8303 8728
fax: +61-8-8303 8750
E-mail: Fred Leaney

[Back to Contents]