TCS Daily

Call Off the Dioxin Dogs

By Michael Fumento - July 20, 2006 12:00 AM

Way back in 1985 the EPA decided it wanted dioxin to be cancer-causing and made it so, labeling it a "probable human carcinogen." Fifteen years later it upped the ante, concluding -- to a round chorus of applause from the media and environmentalist groups -- that the cancer risks for the most exposed people were 10-fold higher than it previously thought. Three years after, it strengthened dioxin's label to "carcinogenic to humans." And last Tuesday ... one big fat fly from the National Academy of Sciences (NAS) plopped into the ointment.

Indeed, the recommendations of the NAS's National Research Council (NRC) review of the EPA's latest draft report on dioxin could -- or at least should -- turn the entire cancer-rating system of the EPA (and other agencies) on its head.

Dioxin is created as an unintentional byproduct of certain industries and processes, including burning trash, land application of sewage sludge, coal-fired utilities, and metal smelting. (It was formerly common in trace amounts in herbicides including Agent Orange, widely used in Vietnam.) As a result, we all carry dioxin in our bodies.

Although dubbed "the most dangerous chemical known to man," incredibly this was based entirely on the acute toxicity (poisoning) to a single species of animal -- guinea pigs. In humans incredibly massive doses have never been shown to cause any long-term damage besides severe acne, as was the case with Ukrainian President Viktor Yushchenko in 2004.

The cancer accusations didn't come along until much later and now the Veteran's Administration makes "presumptive" payments to Vietnam vets with certain cancers regardless of evidence of exposure to Agent Orange exposure and notwithstanding that an ongoing study re-evaluated every three years of those with by far the highest levels of exposure have indicated no increased risk.

The NRC committee was split on whether the available evidence met all the criteria for classifying dioxin as "carcinogenic to humans" under the new guidelines, but it was unanimous in agreeing that dioxin should at least be considered "likely to be carcinogenic to humans." That would seem to at least justify the EPA's original 1985 decision but doesn't.

That's because while it's long been accepted that for acute toxicity that "the dose makes the poison" the EPA uses as a rule for all potential carcinogens that if exposure to a rat of something at a level of, say, a quart a day for 30 years is cancer-causing then exposure of a hundredth of a gram a day for one week must also be carcinogenic to humans. No matter that FDA doesn't advise against women taking a daily iron pill because if they took 100 daily they would die.

It was this EPA assumption that the National Research Council directly challenged, concluding the "EPA's decision to rely solely on a default linear model lacked adequate scientific support." It said compelling new animal data from the National Toxicology Program -- released after EPA completed its reassessment -- when combined with substantial evidence that dioxin does not damage DNA, is now adequate to justify the use of nonlinear methods for estimating cancer risk at relatively low levels of exposure.

In other words, the EPA can't just choose a formula because it's convenient and serves its political ends. It can't ignore the results of myriad animal and human studies and the determination of how a certain chemical affects human cells in favor of simple mathematics. Nor can it apply that formula because it favors environmentalist groups who make a living by terrifying us into believing that a single molecule of this or that threatens the existence of "peoplekind."

The NRC doesn't go so far as to say the linear model can be sent to the trash compactor. It may have applications in some cases. In fact, the NRC report merely restates conclusions from the EPA's own "Guidelines for Carcinogenic Risk Assessment," issued last year. "Both linear and nonlinear approaches are available," the assessment states and "In some cases, they may be combined in a way that best represents human cancer risk." The problem is in getting the Agency to apply the guidelines it devised.

So where does this leave us regarding both dioxin and other potentially carcinogenic substances? Given the poor evidence for low-dose carcinogenesis of dioxin in humans and that according to the EPA dioxin emissions in the environment have been reduced by 92% since 1987 it would seem time to call off the dioxin dogs. That includes both new government regulations and the environmental groups demanding them.

For every other would-be cancer-causer, we need something besides the knowledge that it kills a certain kind of rat or mouse or hamster when given massive doses. That's just not enough anymore to ban valuable chemicals or to leave tens of millions of Americans in fear that they and their children will sprout tumors like mushrooms because "The Man" wants to stuff his pockets and doesn't care who he sickens or kills in the process.

Michael Fumento (fumento[at] is a senior fellow at Hudson Institute specializing in Science and Health issues.



Re: your first two paragraphs:
That's what makes it pseudoscience -- it never dies or advances in light of the evidence. It is funny that you honestly think sound evidence will turn the issue upside down and compel them to retract their nonsense. In fact, they'll just come back and make louder, more outrageous scare mongering claims and create more hysteria. It's classic.

Objective, critically-thinking scientists are making your same point and are equally incredulous about all sorts of unsound beliefs surrounding food, health and the environment that proliferate today. Replace "obesity" for "dioxin" in your first two paragraphs. It's one of the best examples.

But everybody "knows" dioxin is deadly.
It's not what we don't know that hurts us, it's what we know that ain't so. - Will Rogers

From Fox news:
"The national poll, conducted by Opinion Dynamics Corporation (search), shows that about a third of Americans believe in ghosts (34 percent) and an equal number in UFOs (34 percent), and about a quarter accept things like astrology (29 percent), reincarnation (25 percent) and witches (24 percent)."

The fear of dioxin /salt /pesticides /acidrain /mercury/ yadayada is a sign of the times. Sadly for every believer, theres "two to fleece 'em"

Biut wait? Does this mean we should believe the watermelon-agenda NAS??
I mean, we are assured every day on this site that its findings with regard to human climate change are totally bogus. How can this finding possibly carry any weight?

On this site we are advised to follow the science.
There is no science behind the AGW scare.
There is no science behind the Dioxin scare.

No contradiction at all.

And we know this how?
Because we are all scientists?
Why is the NAS reliable on dioxin, but biased and not credible about human caused climate changes?

dioxin not cleared
The abstract (the only free part) does not say dioxin is harmless. It says that the EPA need to tighten their error bars on their toxicity estimates. It's more like getting a retrial than being aquitted.

It's amusing that some people denigrate the NAS position on global warming and celebrate it (somewhat mistated) on dioxin. Either the NAS is reliable or it is not.

Is there someone on this list who does not want the EPA (or some other organization) to do its best to figure out which chemicals are harmful? The most accurate way would be to expose N humans to varying doses and wait 40 years to see how many get cancer. Is there anyone in this list who wants to do it this way? Otherwise, you have to guess -- use models, estimate low dose response from high dose response, etc. It's not perfect, but it's what there is.

People will start to imagine that science is about finding out the truth, instead of simply confirming previously held prejudices.

The NAS is credible on AGW, it's just that you can't read.

The NAS has never said the things you have claimed for it.

That's funny, considering the source.

The NAS's statements on global warming are actually much closer to those of us and this site's than they are to yours.

Try reading the actual reports, not just the AP version.

When certain methods are known to be faulty, advising against using them is hardly anti-science.

The linear model has been disproven over and over and over again. It's only used because it provides the results the activists want.

Regarding human trials using Dioxin, such trials have been done. Inadvertant, but still relevant. Actual, real human, trials have shown that Dioxin is not a carcinogen.

Yes, the NAS.
Here's what you say:
"There is no science behind the AGW scare."

I have no idea what you mean by "the AGW scare." I have quoted NAS reports repeatedly, verbatim, that show that human caused climate change is, in fact, a reality, and a potentially threatening one. If you want to bring forth language from an NAS report saying that this isn't the case - that human change is non-existent, or negligeable, please do so.

Please back up your claim
A blanket statement 'read the report' is not backup.


>The linear model has been disproven over and over and over again. It's only used because it provides the results the activists want.

What does this have to do wth the NAS studies on climate?

Et tu

Yours is a tu quoque argument and ergo irrelevant. Stick to the topic please.

Hardly irrelevant
the issue is consistency, not a tu quoque ('you're guilty too")

This website continuously posts material calling into question the scientific conclusions and credentials of the NAS. It is therefore clearly relevent when it uses the conclusions of that same NAS as evidence for an argument.

Come again

For heaven's sake, look it up, you're using to narrow a definition of the tu quoque fallacy. Is the NAS right or wrong on the matter in question?

I looked it up
If a publicaion (TCS) routinely attacks NAS conclusions in one area (climate) as wrong, illegitimate and biased (and it does) TCS can't then consistently use the same source as the scientific gold standard to make a case in another area.

>Is the NAS right or wrong on the matter in question?

I'd assume they're correct; they usually are. However, as LG has noted, the statements made by the author seem to have gone past what the NAS study actually found.

However EPA cancer formula is even worse than it appears
The EPA linear formula for estimating cancer risk requires a positive Y intercept. i.e. the official projection method predicts a finite positive risk for developing cancer with zero exposure.....a blatant absurdity. Every half dozen years, the letters pages of Science and similar journals fill with discussions concerning prediction of carcinogenic affects yet the EPA has never corrected this simple error.

The issue here is carninogenicity, not toxicity. The only affect ever actually seen in humans of exposure to sublethal levels of dioxin is chloracne and that takes a considerable exposure.

Good luck
Environmental toxicologists do not use linear model. But even withstanding Mark's lack of technical expertise, it would be interesting to see the studies Mark says are so abundant.

But of course they don’t exist. In fact, I have never once seen Mark back up his claims with references.

Many on this BBS, Mark included, are simply politically-prejudiced antagonist who always supports the neoconservative politics of this web site (itself a daughter site of town-hall dot com web of neoconservative webs sites). So their job is easy. They simply support the authors' points of view and thereby have nothing to consider other than whether or not a particular post fits their agenda. If it doesn't, Mark is always among the first to attempt to discredit the post.

Mark serves well (and often) the contrarians who speak out against the propaganda posted on this web site because he is so transparent and often pointless. His clearly unsubstantiated posts and personal attacks accent the often poorly-worded propaganda that this site has to offer. While it is frustrating to people who really want to improve public health, you shouldn't take this too seriously.

you have cherry picked partial quotes and quotes out of context.

Heck, you have even quoted something, and pretended it meant the opposite of what the words said.

There is no science behind the AGW scare. There are only models, models that have been disproven time and time again.

Zero content
>you have cherry picked partial quotes and quotes out of context.
when? What?

>Heck, you have even quoted something, and pretended it meant the opposite of what the words said.

When? What

>There is no science behind the AGW scare. There are only models, models that have been disproven time and time again.

And the NAS disagrees with you. If you think they do no, please supply a specific reference.

already have, many times, many threads
I'm not surprised that you are pretending to have forgotten.

How about NASA
David E. Steitz, a spokesman for the National Aeronautics and Space Administration,

I've been giving this quite a bit of thought and come to the conclusion that, if this has the side-effect of defunding some enhanced greenhouse = global warming projects, then it is probably a good thing. This might seem a strange conclusion for a site promoting science fact over science fiction, after all, how can we determine the physical facts of the matter with inadequate study? Regrettably, this is not about study and pure science. The funding pool for "climate research" is probably massively excessive, with the unfortunate side-effect of massive incentive for claims of crisis. Where once the field of climate study was almost an esoteric field the cries of crisis -- and associated political allocation of huge budgets -- have seen its transformation through bandwagon to current juggernaut. This has done nothing good for either science or society.

The science that is settled, that which can be demonstrated in the lab, is that doubling the concentration of carbon dioxide in the atmosphere (compared with pre-Industrial Revolution levels) can only deliver a trivial near-surface warming, a fraction of a degree which cannot possibly be discerned amongst the noise of natural climatic variation. Everything else, all the claims bought by tens of billions of dollars of public money thrown at an alleged "problem", amount to the digital equivalent of readings of the entrails of chickens. For all the claims of unmitigated positive "feedbacks" used as multipliers for the provably trivial effect of increased atmospheric carbon dioxide even the IPCC (whose mission is to find scary warming) can only identify a possible 0.6 ± 0.2 °C warming from all causes from a time when it was uncomfortably cool (and half of the suspected change occurred prior to the bulk of emissions from fossil fuel use).

Even our recent planetary climate history is somewhat vague. We're all pretty well agreed that at least the North Atlantic region and probably the Northern Hemisphere, if not the world, suffered unfriendly cold around 400 years ago and that it has warmed somewhat since. We're all pretty well agreed that this warming began prior to the Industrial Revolution. We're all pretty well agreed that it is much easier to feed the global population and requires less infringement on wildlands and wildlife habitat when the world is warmer rather than cooler, as it was some four centuries past. We view this as a crisis solely because there now exists an entire industry whose existence and finance depends on creating and maintaining the impression this is so.

If we insist on using global mean temperature as our yardstick, and there remains no compelling argument this is a particularly useful metric, then the science is telling us that our carbon emissions have but trivial influence. If we look to the practical metrics of local cause and effect then global carbon emissions disappear as significant contributors. Why should we keep over-funding groups to create scary scenarios in the virtual worlds of computer models that bear no apparent relation to the behavior of the real world we inhabit?

there's a big difference between not citing sources you agree with, and not citing sources.
of course, you seem to be intellectually incapable of seeing anything that you disagree with, so in your case, the two might situations might actually be synonmous.

Then it should be no trouble at all...
... for you to produce a quote from the NAS saying that human-caused climate change is not a threat. I don't remember you ever bringing forth any documentation for that. But maybe I'm wrong. Show me.

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