For a number of reasons, I've long been suspicious of doping charging based on positive nandrolone tests. The latest news adds fuel to the fire. Although letsrun.com's front page points out that "unstable urine" would only result in, at most, one "false positive" per 1,000 tests, the USA Today article states that, "In 2004, WADA's 33 accredited labs worldwide found traces of nandrolone in about 300 of 170,000 tests. In 2003, they found about 250 in 130,000 tests." Assuming one "false positive" per thousand tests, that suggests that more than half of the positive nandrolone tests may have been "false positives." That's a lot of careers and reputations destroyed by inadequate testing protocols.
I think that when the spate of nandrolone positives started many of us assumed that this was either endogenous or contamination in supplements (probably both). As you say it's a rather poor choice for anyone who wanted to deliberately cheat and this had been known for a long time, also some of the positive tests came in sports where there would be no performance enhancement reason to take anabolic steroids. Of course at that time the testers had a zero tolerance for nandrolone metabolites and only later introduced a threshold so you can be sure that 'non-dopers' were banned then. I would think that doping with nandrolone is significantly less frequent than suggested by the test results.
Is there any evidence that deliberate doping with exogenous nandrolone is anywhere near the levels reflected in the frequency of positive tests? I have the impression that nandrolone is an unlikely choice for dopers, since detectable quantities of the metabolites remain in the body for a relatively long time, and the anabolic effects of nandrolone aren't significantly greater than what could be achieved with other, less easily detectable steroids.
19-norandrosterone and 19-noretiocholanolone can occur naturally at levels in excess of the 2ng/ml limit and the concentration can increase by a factor of 4 after exercise. Until 1996 the IOC regarded any level of these metabolites as evidence of doping with nandrolone but later introduced the threshold (although an arbitrary one without scientific foundation). It's quite likely that a number of the observed positives referred to result from endogenous 19-norandrosterone and 19-noretiocholanolone.
I suggest you do a Google search for the following:
C. Ayotte wrote:
Spreading wrong information is not helpful. The threshold was/is based upon observations made in the labs testing athletes' samples. No, the concentration of metabolites is not increased with exercise (when tested in controled environment). Yes,the metabolites are detectable for months after an injection of nandrolone. However, the supplements of norandrostenedione and norandrostenediol, available for oral self-administration until January 2005 in many countries, were producing the same metabolites, detectable during approximately one week. This is the source of many positive findings since 1997, along with results due to supplements containing those steroids without mention on the label.
You are assuming that mathamatical independence which is very much not the case. If the situation arises where endogenous metabolites exsist or there is contamination, the A/B sample will correlate very well but both be FALSE POSITIVES!
Classified Ads wrote:
Do not ignore the fact that False positive rates are for one sample. False positives from both samples would be extremely low. Since you have less than a one in a thousand chance of seeing a false positive, the odds of both A and B being false positive jumps to 1 in a million or more.