Nietzsche's Toxicology

CETS writes "If it doesn't kill ya' it makes you stronger, so a little bit of a bad thing might be alright, according to Scientific American which has this article. " If dioxin and ionizing radiation cause cancer, then it stands to reason that less exposure to them should improve public health. If mercury, lead and PCBs impair intellectual development, then less should be more. But a growing body of data suggests that environmental contaminants may not always be poisonous--they may actually be good for you at low levels.""

Comments

nothing new.

[joFFeman]

george carlin's been saying this for years.

No it doesn't...

[Jerf]

...because homeopathy explicitly includes the idea that things get more powerful as the dilution decreases, even past the point that the original substance no longer has even a molecule in the final product. A homeopathy practictioner would thus claim that these exposures are at far too high a level to work, and still need to be diluted by a factor of, oh, at least 10^10 to be more useful, probably more. (That number is not a typo. Yes, Homeopathy shoots right past Advogadro's Number and never looks back.) Homeopathy explicitly claims to be many times more beneficial then these low-level exposures. As they are completely wrong, they still don't win any points. (Nor is this as big a surprise as the article writer thinks it is, it merely establishes some examples of a long-known general principle.)

For those wishing to learn more about homeopathy, please see Homeowatch, and in particular this page which provides an overview of homeopathy.

I have researched this phenomenon

[VendingMenace]

At Lawrence Livermore National Laboratory. It is know as adaptive response. The acticle is slightly misleading though. What is actually observed is that organisms which are exposed to small quantities of a toxin (lets say radiation) before being given a larger dose will experience less damage than those who were exposed to the larger dose without the small "priming" dose.

For example, cells in group A are exposed to a small dose, of raidation, given a few hours to sit around and then are exposed to a large dose of radiation. Group B is exposed to the large dose or radiatoin only. It can then be observed that group A suffers less damage (we quantified it by looking at the damage to the chromosomes, translocations, ect.) than those in group B.

Some caveates to this are...
-If the large dose of radiation is too large, you will not see this adaptive response.
-The time that the cells must wait after teh priming dose is about 6 hours, to short or too long a time and the adaptive response is not observed
-The priming dose also must be within a range of certain values for adaptive response to take place
-In some cases, you see a synergisti response in the radiation. That is the cells exposed to the priming and large dose experience MORE radiation than is expected from just the sum of the radiation that they were exposed too

All the research we did pointed to the fact that there is probably some kind of repair mechanism that is turned on when chromosomes are damaged. By exposing cells to a small priming dose of radiation, you have turned on this mechanism. Thus, when you expose the cells to the larger dose of radiation this repair mechanism is already turned on and the cell can more readily deal with the damage than other cells that have not recived this priming dose.

THis is pretty cool research when you think about it. I mean it affeects alot of stuff, esp in the medical feild. Think about chemotherapy. The idea is to kill cancer by exposing it to a dose or posion. However, the dose that is given is just caculated by body mass. This research alludes to the fact, however, that not all peope will respond the same to long term exposure to posoins. THe long term exposer acts almost like many many priming doses, and, in those people that exhibit greater adaptive response, the therapy will then be less effective. INtersting, no?

Also, there have been several different studies concerning geographical location in the US vs cancer frequecies (melenoma, to be exact). It was found that peope who lived in higher elevations (and thus recieved contiually doses of radiation that were higher than those at low elevations) had less occurance of skin cancer, than those of us at lower elevations. It is definatly hard to prove any connection, but hte thought was that this higher dose of radiation acted like a priming dose and then the higher doses of radiation that people are exposed to durring the summer had less of an effect.

Anyways, i just wanted to vouch for the article and say that the stuff the are talking about (however, misrepresented) does exist. THe practicalitly of it, and how much you should let it affect your behavior (still wear sunscreen!) is up to you. IT is not a very well understood phenomenon, but it is still cool.

SWEET!

Re:I have researched this phenomenon

[Sgt York]

The same thing happens in many models, the one I am most familiar with is hypoxia. Exposing cultures, in situ tissues or even whole animals to short periods of "light" hypoxia will protect them from more severe hypoxia for a period of time. (Look on Pubmed for Kitakaze and his research on nucleotidase in the heart). However, the effect is short term. It only lasts for a few hours.

THe long term exposer acts almost like many many priming doses, and, in those people that exhibit greater adaptive response, the therapy will then be less effective. and the caveat, If the large dose of radiation is too large, you will not see this adaptive response

Although I don't know what the limits are in your work, I imagine (perhaps incorrectly) that the doses given in most radiation treatments are a bit large for adaptive response to kick in before the damage is too great. Besides, the (observed!) drecrease in efficacy of radiation treatment over time is probably quite well explained by natural selection. The first few doses kill off the cancerous cells that are sensitive to radiation, leaving only those that are less sensitive.

It's not always good, either. If you prime your liver with ethanol, and get the cleanup pathways activated, then take in a sublethal (for normal circumstances) dose of methanol, it will kill you. Because the pathways are already going full blast, the methanol is converted into its toxic breakdown products much more rapidly. Ying and Yang.

One last thing, because most of these responses are due to the activiation of a repair pathway, the protection given is short lived. These pathways are timed, and shut down after the stimulus is gone, at least normally. This is a Good Thing. Repair pathways gone awry are not good (some tumors, fibrosis, "Proud Flesh").