New test tells how much you drank weeks ago

Main Category: Alcohol / Addiction / Illegal Drugs
Article Date: 12 Feb 2004 - 0:00 PDT


Soon it will be possible to tell how much a person has been drinking (over the last few days) by carrying out a hair test.

These hair tests (and also blood and urine tests) can tell not only how much you have drunk over the last few days, it can accurately tell over the last few weeks or even months.

Although alcohol only takes a few hours to leave the body, drinking it produces chemicals, these chemicals stay in the body for quite a long time.

Currently, there are tests that show whether you have been drinking. However, these tests rely on indirect evidence (level of liver enzymes in the blood). The results of these tests are not completely accurate (other toxins influence the results, pregnancy influences the results).

Scientists say that by using a combination of tests (including hair tests) it is easier to get a complete picture of someone's drinking habits. It can show when someone last drank and whether they have been drinking heavily or not.

The possible uses of these tests are mind-boggling:

- Airlines could test pilots and crew
v - Police could test someone days after an accident

- Employees could be tested at random. How would the person be able to cover up for something he or she did a couple of weeks ago.

The tests look for a chemical produced when the body processes alcohol.

These chemicals appear in the blood within 12 to 18 hours after someone has had an alcoholic drink. They are called fatty acid ethyl esters (FAEEs). Eventually, these chemicals are stored in the hair.

Dr Friedrich Wurst of the University of Basel in Switzerland, one of the scientists involved in the research, monitored around 40 drinkers and teetotallers.
v It was found FAEE levels accurately distinguished between light and heavy drinkers.
v He said that there is only one way someone could make sure that no one found out what he had been up to - to shave his head.
v A chemical called phospatidyl ethanol (PEth) remains in the blood for up to three weeks in people who drink more that three beers a day, or the equivalent.

Another chemical, ethyl glucuronide (EtG) accumulates in the blood as alcohol levels fall.

Dr Wurst, said: 'Ethyl glucuronide, plus the absence of alcohol itself, indicates a potential hangover state.'

It remains in urine for up to five days and proves that someone has had a drink during that time.

'No comparable tests'

Dr Charles Lieber of the Mount Sinai School of Medicine in New York, said the tests could be extremely useful.

'We don't really have comparable tests for prolonged intake.

'We don't have anything comparable in place, and there is potential there.

'But it is important that it is duplicated by other investigators.'

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