Sunday, October 25, 2015

Public health, endocrine disruption and the precautionary principle

Several years ago over lunch a medical researcher I know told me that industrial chemicals were disrupting the human endocrine system leading to widespread obesity and diabetes. He said his research had revealed an important cause--the decline in the production of testosterone in both men and women (yes, women produce a little testosterone) due to this disruption. When this deficiency was reversed, patients experienced significant improvement in both obesity and diabetes.

That's not all. He explained that most people believe that poor diet and little exercise are the central cause of obesity and diabetes. No doubt poor diet and exercise are important contributing factors. But when the body's signaling system fails to indicate when it has had enough to eat, it's hard for most people to recognize that they need to stop eating. How many of us know people who say that they are hungry all the time? A normal human being with a normal endocrine system should not feel "hungry all the time."

The link between what has become a sweeping twin epidemic and man-made chemicals is getting wider notice these days. But the link between endocrine disruption, obesity and diabetes is still absent from popular medical accounts such as those found on WebMD for obesity or on official sites such as that of the World Health Organization.

Endocrine disruption has also been linked to cancer, reproductive failure, neurological disorders and developmental problems in fetuses, problems that can lead to illness later in life. In fact, industrial chemicals known to disrupt endocrine function are found in humans and animals worldwide.

The subject of endocrine disruption first burst into the public mind with the publication of Our Stolen Future in 1996 by three scientific researchers. They sought to make the issue more accessible to the public in order to galvanize action.

A few companies have voluntarily eliminated a known disruptor from the linings of food cans and in plastic bottles and containers. But the disruptor, bisphenol A, commonly referred to as BPA, while banned from baby bottles, continues to be used widely.

Just this year European regulators affirmed the safety of BPA at low levels for adult exposures. The problem, of course, is that human endocrine compounds perform their signaling in the body at extremely low levels, parts per trillion or even parts per quadrillion. As a result the idea that there is an acceptable low dose is questionable.

And, therein lies a difficult regulatory problem. Since known endocrine-disrupting chemicals do their disrupting at extremely low concentrations, nothing short of a complete ban would likely keep them from affecting humans and animals.

What this means is the entire human and animal population of the planet is now involved in an uncontrolled experiment courtesy of the chemical industry. We are all exposed to a soup of man-made chemicals every day, some of them endocrine disruptors.

The industry says it is up to the public to prove somehow that these so-called disruptors are present and dangerous. How the public would build the expensive facilities and pay the high-level personnel needed for such a task is ignored. Government regulatory agencies and a few university laboratories have taken up some of this work.

But this puts the burden of proof in the wrong place. It should be the industry which proves that novel chemicals put into food or released into the environment are safe for humans and animals.

This approach is commonly known as the precautionary principle. It essentially places the burden on the company to prove a novel chemical is safe BEFORE it is introduced into society and the environment. The European regulatory authorities implemented such an approach in 2007 called REACH over the loud objections of the chemical industry. The authorities have put the industry on notice that chemicals of "very high concern" will either have to be shown to be safe or be phased out. (That REACH does not classify BPA as dangerous to adults shows that even cautious European regulators don't understand that very low doses can be damaging.)

The precautionary principle embodied in REACH is simple. If you are going to expose anyone in the public to a man-made substance without explicit consent, you need to prove that the substance is benign or of such great benefit to society that the risks associated with exposure are worth the danger. This is a very high bar to clear, and many toxic chemicals won't make the cut under the European rules.

Partly, this is because regulators granted a 10-year grace period during which chemical makers have had an opportunity to find less toxic or nontoxic substitutes. Without REACH, it is doubtful the industry would have bothered to do so.

Estimates of the number of man-made chemicals vary. The number 80,000 is frequently cited. A more recent piece claims the number is 143,000 with only 800 tested for endocrine disruption.

So-called "green chemistry" is one response in an effort to find chemicals that minimize environmental and health impacts.

Meanwhile, the public health effects of endocrine disruption are growing, undermining the health and happiness of millions across the planet. And, the costs are mounting for the treatment of obesity, diabetes, cancer and a host of other health problems related to the great global chemical experiment in which we are all participants, whether we wish to be or not.

The chemical industry is risking nothing short of a rebellion by the public and governmental authorities if it continues to fight sensible precautionary regulation. Will the day come when there will be enough evidence to link obesity or diabetes or both more directly to chemical exposures? If that day comes, it will be the beginning of the end of impunity for the chemical industry as the legal establishment feasts on the toxic profits of the companies at the center of the epidemic.

The World Health Organization estimates that 9 percent of all adults over 18 have diabetes. I couldn't find global population figures for those 18 and older. But of those 25 and older, that must mean that approximately 372 million have diabetes worldwide. If the fight over diabetes becomes a legal battle similar to that experienced by tobacco companies, the plantiffs' lawyers will run out of chemical companies to sue long before they run out of clients.

Kurt Cobb is an author, speaker, and columnist focusing on energy and the environment. He is a regular contributor to the Energy Voices section of The Christian Science Monitor and author of the peak-oil-themed novel Prelude. In addition, he has written columns for the Paris-based science news site Scitizen, and his work has been featured on Energy Bulletin (now Resilience.org), The Oil Drum, OilPrice.com, Econ Matters, Peak Oil Review, 321energy, Common Dreams, Le Monde Diplomatique and many other sites. He maintains a blog called Resource Insights and can be contacted at kurtcobb2001@yahoo.com.

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