I can think of a couple of examples where something toxic at a high level is not necessarily toxic at a low level. Vitamin C and A are both toxic at high levels, but who wants to argue that there is no safe level of exposure or no benefit. Certain metals, such as selenium, are toxic at high levels, but may be beneficial at low levels. Isn’t the concept of a low dose challenge to the immune system behind the theory of vaccines. The linear no-threshold approach does not fit every situation. That is not to say that every chemical or bacteria is beneficial, but neither is it true that every chemical or microbe is dangerous an any level, no matter how low. I think this article misrepresents and overgeneralizes the work of Dr. Calabrese.
Et al,
Having been rather lll and in the hospital all last week, this is the first I've seen of this.
What kind of idiotic, moronic nonsense are we up to now? Bringing to environmental regulatory science and public health clearly discredited principles that used to constitute homeopathic medicine?
As to politics, I am a medium conservative republican who didn't like either choice for President last time around and so chose the one I though was least awful.
Climate change is clearly real. What is not clear is how much anthropogenic activities contribute to it or if it was going to happen anyway (as it has many times in the past)..
A book on the econmoincs of climate change I reviewed for a journal a few years ago lead me to the conclusions that we can no longer afford all of us in terms of a sustainable environment, and that whether or not anthropogenic activites contribute significantly to climate change or not, what's wrong with having clean air to breath, clean water to drink, and sa afe and adequate food supply, etc., etc. etc.
Are there "safe" levels of pollutant exposure? Quite difficu;t to say. There are levels below which we are currently not able to detect adverse effects, but that doesn't mean with long-term and usually multiple complex mixture exposures that they clearly do not exist. Public health should whenever possible err on the side of being to conservative rather than the "let the breather beware" lassez-faire approach.
Maybe I'll cogitate on this some more later when I'm more up to par, but this approach to me seems sheer lunacy.
Clinical Asistant Professor
Colrado School of Public Health
University of Colorado-Denver
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