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De Omnibus Dubitandum - Lux Veritas

Saturday, November 3, 2018

My Definition of a Scientist

By Frank Schnell — October 31, 2018

A scientist is a person who is able and willing to live with uncertainty as long as it takes to dispel that uncertainty through an objective, logical process (a.k.a. the Scientific Method).Most non-scientists are victims of a potentially dangerous combination of two common attributes of human intelligence:

(1) an extreme aversion to uncertainty and
(2) the ability to rationalize.

The former is expressed as a fear of the unfamiliar which inhibits one’s evolution from Frightened Animal to Thinking Human Being. The latter enables one to intellectually neutralize discomfiting truths or uncertainties and is used (especially, but not exclusively) to support political and religious ideologies. In their darkest forms, those ideologies give one permission to continue behaving like a beast while still imagining that one is a superior life form. .........To Read More....


Will "Alternative Truth" Prevail?

Credit: John Tenniel

“When I use a word,” Humpty Dumpty said in rather a scornful tone, “it means just what I choose it to mean — neither more nor less.” - Alice in Wonderland


Science is, above all, a methodology designed for discovering objective“truths” about the natural world. All lawyers and politicians speak quite highly of Truth, and all routinely claim that it is on their side, rather than their opponents’, however, the real function of legal and political debate is not to discover truth, but to win. And, whenever “winning” is the prime directive, Truth is always the first casualty in the battle..........To Read More....

The Age Of Stupid

By Frank Schnell — August 19, 2016

When, exactly, was the Age of Stupid? Was it when people practiced human sacrifice to placate the brutal gods they worshiped? Was it when people believed the Earth was flat and everything else in the universe revolved around them?  Or, was it when people thought that all diseases were due to an imbalance of the four humours and could be treated by bleeding the patient?

Maybe it was when they believed in witches and burned them alive at the stake for the on-lookers’ entertainment and spiritual enlightenment.  Or perhaps it occurred more recently when people took “comet pills” to protect themselves from cyanogen gas in the tail of Halley’s Comet, which they believed would envelope the Earth and cause mass extinction.

Surely, the Age of Stupid was in full flower when people believed in Piltdown man and perpetual motion machines, zero-threshold environmental toxins, and catastrophic anthropogenic global warming. Or it’s the Age of Stupid today.........To Read More....

Chemicals, Cancer and Common Sense

By Frank Schnell — April 15, 2016

Risk Estimation:  It would come as a surprise to most people to learn that so-called quantitative cancer risk assessments do not actually quantify true risk.  The actuarial risk calculated by insurance companies (e.g., the risk of dying in an auto accident), is based on actual data on the incidence of disease-, disaster- or accident-related mortality. 

However, actuarial data on disease incidence or mortality in humans resulting from very low exposures to chemicals in the environment simply do not exist. 

Instead, data from occupational studies of more heavily exposed humans are used, where available.  However, epidemiological studies seldom have the quantitative exposure data needed for a quantitative risk assessment.  To create a surrogate for this missing low-dose data, animals are exposed to very high doses of substances to guarantee that statistically reliable results are obtained. 

These animal results (or, much less often, the results from occupationally-exposed humans) are then extrapolated, using mathematical models incorporating numerous default assumptions, to humans exposed to very low environmental levels of the same substance.  The resulting cancer risk calculated by regulatory agencies is, of necessity, entirely theoretical and will vary greatly depending on the assumptions made and the models used in the assessment.  The limitations of quantitative risk assessment were clearly acknowledged in EPA's 1986 Guidelines for carcinogen risk assessment, as follows:

“The risk model used by EPA [i.e., the linearized multistage model] leads to a plausible upper limit to risk that is consistent with some proposed mechanisms of carcinogenesis.  Such an estimate, however, does not necessarily give a realistic prediction of the risk.  The true value of the risk is unknown, and may be as low as zero."  (U.S. E.P.A., 1986)      (emphasis added.)..........To Read More.....

War On Science: Bogus Human Carcinogens

By Frank Schnell — March 10, 2016

In the last 15 years, EPA has invented three bogus human carcinogens: dioxin, formaldehyde, and TCE.

Prior to the late 1990s, EPA’s cancer Risk Assessment Guidelines (CRAGs) required sufficient evidence of a cause-and-effect relationship in humans before a substance could be classified as a “known human carcinogen”.   However, during the late 1990s, EPA modified its CRAGs to allow itself to classify substances as known human carcinogens without sufficient epidemiological evidence to support such a decision.

The new CRAGs were specifically designed to enable the agency to classify the “celebrity” pollutant dioxin as a human carcinogen, using the agency’s speculative policies (e.g., the so-called TEF approach to the risk assessment of “dioxin-like” compounds) as surrogates for the missing evidence of carcinogenicity in humans.

Dioxin had been a “celebrity” pollutant ever since it came to public attention during the Vietnam War. The chemical’s status followed, not from the its known toxicity in humans (which was largely limited to chloracne, a serious skin condition associated with heavy exposures), but from its association with the second most divisive war in American history.  EPA’s determination to classify it as a human carcinogen had little to do with toxicology and everything to do with the politics of pollution............To Read More....


How Natural Variations Became Environmental Crises: The Word Game

 By Frank Schnell — February 16, 2016

In How Natural Variations Became Environmental Crises: The Numbers Racket, we looked at how officially safe levels of exposure gradually went from conservative, to ultra-conservative, to completely ridiculous.

Even before the manipulation of numbers became commonplace, the manipulation of words was a major tool in promoting fear about science and keeping it alive. Simple words in common usage, like risk, known, similar and equivalent were given esoteric, colloquial meanings that bore little resemblance to their definitions in Webster s Dictionary and of which the general public was completely unaware..

Thus, unbeknownst to the average citizen, EPA s so-called quantitative cancer risk assessments have never assessed the true risk of potentially carcinogenic exposures. In EPA s 1986 Risk Assessment Guidelines, the following, uncharacteristically honest, and seldom quoted (except by me) statement was made: The true risk is unknown and may be as low as zero. Obviously, if the true risk is unknown, then the risk that is supposedly quantified in EPA risk assessments is not the true risk.

Throughout my career as an ATSDR toxicologist, I routinely quoted the zero true risk statement in all of my toxicological evaluations for health assessments that addressed potential cancer hazards on site. And, it never failed to irritate agency management and even some of my colleagues......To Read More....

How Natural Variations Became Environmental Crises: The Numbers Racket

By Frank Schnell — February 15, 2016

George Washington may be the only popularly elected ruler in history who, when his supporters offered to crown him King, relinquished his power instead. Politically speaking, that was a very unnatural thing to do.

Historically, federal agencies have not surrendered their power, even after their congressional mandates were accomplished. Instead, they have invented new problems to solve, thereby justifying their continued existence.

The Environmental Protection Agency (EPA) was created by Congress in 1970 to write and enforce regulations designed to protect the environment and, by extension, human health. The Agency for Toxic Substances and Disease Registry (ATSDR), a sister agency of the Centers for Disease Control (CDC), was created by Congress ten years later (1980) as a non-regulatory public health information agency that analyzed the public health implications of environmental data provided by EPA and others, and wrote Public Health Assessments for concerned citizens at contaminated sites...........To Read More.....

Dose-Response, NOAELs and Hormesis

By Frank Schnell — January 22, 2016

In the 16th century, Paracelsus, the Father of Toxicology, established that All substances are poisons; there is none which is not a poison. The right dose differentiates a poison from a remedy.

The truth of this 500-year-old statement should be intuitively obvious to anyone who has ever taken aspirin for a headache. If you take too little, you will get no relief; if you take the right amount, your headache will go away; and, if you take too much, your ears will ring and your stomach will hurt.

Thus, dose alone determines whether a substance (aspirin in this example) will have an adverse effect (a poison), a beneficial effect (a remedy), or no effect at all.

One could describe most modern medications as judiciously applied poisons.........To Read More....

Dr. Frank Schnell, PhD, is a retired toxicologist for the Agency for Toxic Substances and Disease Registry, part of the CDC, in Atlanta, Georgia, and is a member of the American Council on Science and Health Scientific Advisory Panel.
 

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