Hair testing efficacy?

[Chuff]

I am increasingly encountering people who are having hair strand tests, usually from social services as evidence to remove/not remove a child to care and there seems to only be one company in the Uk delivering this service and they are reluctant to discuss false positives or the level of accuracy of their product.

putting aside the very serious issues of does taking drugs make one an unfit parent (No it fucking dosen't) and the predjuices evident in some social workers around this, many clients do lie, understandably about their drug use to social services, social services can then use a hair strand test to proove a client has lied undermining any progress they may have made regarding problematic drug use.

so my question is does anybody have any evidence about the levels of accuracy of hair strand testing either in the Uk or the USA (or anywhere else) any info on false positives etc etc.

thanks

Cliff

 

[vecktor]

^ Can you name the company UK social services are using?

 

[sciencedj]

Hair Tests
Are currently several times more expensive than urine tests (~$100-$150).

Are considered a relatively unintrusive method of drug testing.

Detect substance use over a longer period (see detection period).

Do not usually detect use within the past week.

Require a sample of hair about the diameter of a pencil and 1.5 inches long.

They can not be done with a single hair.

Test positive a little more than twice as often as a urine test. In a recent study, out of 1823 paired hair and urine samples, 57 urine samples tested positive for drugs of abuse; while 124 hair samples from the same group tested positive.

Are not significantly affected by brief periods of abstinence from drugs.

Can sometimes be used to determine when use occured and if it has been discontinued. Drugs, such as opiates (codeine, morphine, heroin) lay down on the hair shaft very tightly and are shown not to migrate along the shaft, thus, if a long segment of hair is available one can draw some "relative" conclusions about when the use occurred. However cocaine, although very easy to detect, is able to migrate along the shaft; making it very difficult to determine when the drug was used and for how long.

Claims to be able to reliably differentiate between opiate and poppy seed use.
We've heard that many hair tests now check for more than the NIDA 5, and include at least Cannabis, Ecstasy/MDMA, Cocaine, Opiates, Methamphetamine, Amphetamine, Phencyclidine (PCP), Benzodiazepines, & Barbiturates (2001).

Source: http://www.erowid.org/psychoactives/testing/testing_info1.shtml

Drugs can be detected for a period of up to 90 days

I hope this helps

 

[Chuff]

thanks, thats a good start, I am putting out some legal feelers re the right to remove a child on a hair strand test as i am getting the feeling this is dodgy ground.

 

[vecktor]

thanks, thats a good start, I am putting out some legal feelers re the right to remove a child on a hair strand test as i am getting the feeling this is dodgy ground.

it is not a feeling it IS dodgy ground.

No distinction between drug use and problematic drug use.
No evidence that harm has or would occur to the child as a consequence of drug use, rather it is assumed that as there is evidence of drug use then that parent is unable to care for the child.
If there is evidence that the child has been harmed or is likely to be harmed then surely that is the evidence that should be used, and there would be no need for the hair test evidence.
perhaps the yummy mummies of Islington should be tested and their children taken away when they test positive for cocaine.

As for whether the state has the right to remove a child on a hair test, well they write the rules and they can if they want. previously social services have removed children on much flimsier evidence.

Whether it is right that the state has the right is another matter entirely.
What is in the childs best interest?

The state should only interfere with the private lives of its subjects in the most severe and dire circumstances, particularily when it comes to placing children in care, the state is an abysmal parent, and so are the social services.
Taking children into care often has less to do with the welfare of the child and more to do with covering the butts of the social workers, who will be villified if a child is harmed, often more so than the actual perpetrators, who will be excused on account of it was the drugs or it was the culture or it was their upbringing.

 

[Chuff]

The primary criticism of hair-testing is related to concerns that hair might be contaminated externally by drugs in the environment (Kidwell & Blank, 1996). It is suggested, for example, that a person sitting in a room where cocaine is being used or handled might have traces of the drug deposited on the surface of the hair, which might then be dissolved (for example in sweat) and absorbed by the hair. The person might later test positive for cocaine in hair, even though they had not ingested it. Blank and Kidwell (1995) report the use of radioactive labelling to demonstrate that cocaine can be absorbed into hair from aqueous solutions and that subsequent attempts at decontamination will remove some, but not all, of the drug. External contamination may be greater in hair which is bleached, 'permed' or greased than in untreated hair (Thorspecken et al, 2004).1

In response to these criticisms, testing procedures have developed over time in order to reduce the risk of false positive results. These procedures may include 'kinetic washing', where hair samples are washed in various solvents. It is not assumed that all external contamination could be washed out. The concentration of contaminants in the wash-off from multiple washes are measured and a specific pattern of declining concentrations in successive washes is considered to be indicative of external contamination. Most important, it is now considered good practice to test not for the drug itself, but for metabolites of the drug which are produced by its metabolism in a living mammal. It is argued that the base drug might be deposited externally by innocent exposure, but it is improbable that metabolites of the drug could be laid down in the matrix of the hair in this way. The issues and responses regarding contamination are discussed in detail in Baumgartner & Hill (1996).

got given this on another board!

 

[Photon]

Hair tests are unreal, i got hair tested by the courts and it told them every drug that I have ever tried, I couldn't believe it.