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Infants Ingest 77 Times the Safe Level of Dioxin
An anonymous reader writes "The Environmental Protection Agency is holding public hearings beginning today to review a proposed safe exposure limit for dioxin, a known carcinogen and endocrine disruptor produced as a common industrial byproduct. It's all but impossible to avoid exposure to dioxin. Women exposed to it pass it on to fetuses in the womb, and both breast milk and formula have been shown to contain the stuff. Research done by the Environmental Working Group has shown that a nursing infant ingests an amount 77 times higher than what the EPA has proposed as safe exposure. Adults are exposed to 1,200 times more dioxin than the EPA suggests is safe, mostly through eating meat, dairy, and shellfish."
Not necessarily. It depends on how "safe" is defined. If "unsafe" means that you can expect a statistically measurable drop in life expectancy and measurable increase in related illnesses over a lifetime of exposure (ie: pretty much the same case as you have for smoking-related illnesses), then you would not necessarily have an obviously sick population even though said population was, indeed, sick - merely not sick enough for it to be visible at that time.
Lifetime exposure is one factor. Yearly exposure and daily exposure are other measures. I don't know exactly which of these the 1200x refers to. It matters. It matters a lot. You can't simply assume that exposure is utterly uniform and devoid of any fluctuation, nor can you assume that accumulation is also uniform and devoid of any fluctuation. Thus, the 1200x may well be an average that never actually happens, but where you are very likely to get millions of times safe levels for brief periods of times at intervals in your life. Or it might be that 1200x is the maximum value that the fluctuations are likely to reach, or it might be the root-mean-square value of the fluctuating values, or any number of other things. The summary is useless (as usual) in understanding what the numbers mean.
Or maybe 1200x is not actually the exposure level at all, but rather the peak value observed for bodily accumulation of the toxin. Or the average. Or the root-mean-square. Or some other statistical value.
Regardless, the EPA is usually wildly optimistic - the EU generally permits levels only half the EPA estimates of what is safe, and the value is generally much closer to the value considered sensible by environmental chemists and inorganic biochemists. Both the EPA and EU values are usually also much lower than the values industry will stomach, with the result that either the law is widely flouted (since jobs = votes and nobody is stupid enough to vote themselves out of office by risking jobs through environmental crackdowns) or the law is widely bypassed by moving the most polluting component(s) to places like Bhopal, where the people are too poor or too dead to complain.
(I don't know what the solution is, but since a company pays for whatever it wastes, it would seem to follow that the less you waste the more you make.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
"Nine animal studies conducted between 1973 and 2008 show that dioxin is harmful at levels even lower than in the human studies on which EPA based its proposal. Those human studies, conducted in 2008, explored the toxic legacy of a 1976 chemical plant explosion in Seveso, Italy, which exposed thousands of people to dioxin in unprecedented intensity and left large quantities of the chemical in the soil." source: http://www.ewg.org/dioxin/home
of course ... those studies could have all been flawed ... but ... it's a much more likely possibility that the cancer all the people you know that have cancer comes from something related to their lifetime of high exposures to environmental pollutants.
here's the EWR's press release http://www.ewg.org/dioxin/press
Environmental Working Group's dioxin timeline, complete with citations http://www.ewg.org/dioxin/timeline
I'm a vegan, politcally I'm a progressive (let the flaming begin), and even I was disgusted with the "article" linked in TFS. Piss poor choice dudes, as you easily could have linked to the EWR's press release and allowed the discussion to go from there. But instead we start with a shit "article" from an alarmist site, which stokes an immediate onslaught of comments that outright dismiss even a _possibility_ that dioxin is harmful to humans.
In my 12 years of hanging around here, I sure do miss the days when we'd have a discussion based on the SCIENCE of whether or not dioxin is worthy of our concern
That said, I agree that the "1200 times safe levels" quote is fear-mongering. Humans are notoriously bad at judging relative risk (see the Bad Science blog for more).
From the WHO site:
In short, dioxins' real danger is not increased cancer risk in the population that ingests it directly. It's the mutagenic risk to our offspring. In layman's terms, you're not going to die of cancer, but your child might be born with a genetic defect that affects their ability to thrive - or maybe even to survive.
A 'safe' dose is therefore difficult to quantify, because we won't know for sure what the impact will be after (for example) 3 generations of exposure at a given level. More to the point, we don't want to find out by waiting to see if our predictions were right. In cases like this, the precautionary principle is by far the better choice.
That's difficult to apply, however, because dioxins are persistent chemicals; they accumulate in the food chain and don't disperse easily. Arguably, there is no such thing as a 'safe' level, because with the passage of time even small annual increments become very large numbers.
As with climate change, decisions deriving from the scientific findings will be largely informed by the moral/ethical/philosophical stance of the policy-makers. The same data set looks very different if you're looking at the problem in terms of the next electoral cycle, as opposed to the next generation.
Crumb's Corollary: Never bring a knife to a bun fight.