A significant breakthrough in the worldwide fight against illicit drugs has been developed by ANSTO scientists, in conjunction with the Australian Forensic Drug Laboratory (AFDL).
Seized drugs such as opium, morphine, heroin and cocaine are often measured for impurities to pinpoint their origin. However, this analysis does not convey information on when a drug sample was grown.
AFDL and ANSTO scientists have now demonstrated that carbon dating – the method better known for use on ancient relics such as Aboriginal rock art–provides this information.
This will furnish law enforcement agencies with accurate evidence on cultivation and distribution patterns. It will also provide vital information on whether certain countries have stockpiles of drugs by the time of their appearance on the market relative to their actual growth date.
Operations can then be put into place to seek out these stockpiles. Using samples obtained in recent drug seizures, AFDL ascertained where the drug came from by measuring the identifiable impurities in the sample. These drug samples were then transported to ANSTO for radiocarbon dating.
Dr Ugo Zoppi of ANSTO Environment said atmospheric radiocarbon (14C) levels surged due to atmospheric nuclear testing in the 50s, during a period dubbed ‘The Cold War’.
“Since the Nuclear Test Ban Treaty came into effect in 1963, the levels of atmospheric radiocarbon has continued to decline each year. Today, the 14C level is only 10 percent greater than the pre-bomb level,” Dr Zoppi said.
“Atmospheric radiocarbon levels have been determined each year by measuring 14C in atmospheric CO2, tree rings and ice cores. “The amount of 14C in the drug samples is checked against the records of annual levels and the date the plant was grown is then determined.
This information is then forwarded to the appropriate authorities,” Dr Zoppi said. “ANSTO scientists used an highly sophisticated processes to enable measurement of minuscule amounts of 14C in the plant material (found in one part for every one thousand billion or less of other carbon isotopes).
” ANSTO’s Accelerator Mass Spectrometry (AMS) group conducts these measurements. AMS is an analytical technique based on the use of an ion accelerator such as the Australian National Tandem Accelerator for Applied Research operating at Lucas Heights.
Carbon dating has also been used to date vine vintages and to reveal the use of unauthorised additives.
Published: 08/01/2003