What’s up with the frogs?

The rapid decline of the amphibians suggests a major chemical catastrophe is in the offing

by Michael Nenonen <mnenonen@republic-news.org>

I like frogs. As a little boy I thought they were charmingly ugly, I enjoyed the noises they made, and I found their composure strangely soothing to behold. But what's happening to them lately is arousing my concern.

Around the world, frogs and other amphibians are disappearing. This can be partially explained by human development, loss of habitat, and the arrival of invasive species into the amphibians’ ecosystems. It's also likely that their delicate bodies are being excessively bathed in the flood of ultraviolet radiation that's pouring through our crumbling ozone layer. Even if we combine these causes, however, we still can't account for the magnitude of the decline. There's something else going on, something we better pay closer attention to.

According to Theo Colborn, Dianne Dumanoski, and John Peterson Myers, authors of Our Stolen Future (Dutton, 1996), the amphibians may be casualties of the chemical saturation of our environment.

Our Stolen Future focuses on the ecological role of endocrine disrupters. An endocrine disrupter is any compound that interferes with the developing body's hormonal systems. These exquisitely-balanced systems guide our physical and mental development. Our reproductive, neurological, and immune systems all depend on intricately organized hormonal signals.

There are many kinds of potential endocrine disrupters. They include estrogens, estrogen blockers, androgen blockers, progesterone blockers, and compounds that interfere with the thyroid. There are a fantastic number of compounds that can play these roles. They include persistent organohalogens like chloroform, dioxins, PPBs, and PCBs; metals like mercury, lead, arsenic, and cadmium; pesticides like DDT, thiram, fipronil, and atrazine; phthalates like BBP, DBP, DEHP, and DEP; food antioxidants like BHA; and even certain plastics. The authors' regularly-updated website, ourstolenfuture.org, lists over eighty compounds known to have these effects. Each compound is used heavily somewhere in the world; many of them are regularly used here in North America. Over 60% of innercity children in Philadelphia, for example, carry lead levels above criteria established by the US CDC for lead poisoning.

Regardless of where they're used, they’ll eventually spread across the biosphere. Laboratory tests are revealing that many have impacts at levels far below expectations normally held in traditional toxicology. Of course, in the laboratory they’re tested in isolation; in the real world, they appear in combination with one another. Even if each compound is found in quantities beneath the threshold normally required for noticeable effect, their interaction when mixed can easily push them past this threshold. There's simply no way to test for the effects of all the possible combinations that occur in our environment.

Here’s where the frogs come in. An amphibian’s skin is uniquely sensitive. If endocrine disruptors are poisoning our environment, amphibians will be the first to suffer the effects. Consider, then, that frogs aren’t just disappearing. Frogs with bizarre appearances are being found everywhere. Researchers in Minnesota recently uncovered horrifically deformed frogs at more than 100 sites. One frog had four legs sprouting from its stomach, while another had a leg growing out of its neck. Most astounding was a frog with an eye growing inside its mouth. Such deformities are consistent with the effects of widespread endocrine disruption.

Human beings aren't as vulnerable as frogs, but we also have endocrine systems, and we’re also doused in endocrine disruptors. Today, every human body contains literally hundreds of chemicals that simply didn't exist prior to the twentieth century; most entered our environment only after World War Two. Modern human beings have been around for over 100,000 years, and yet our bodies are full of chemicals that were completely unknown barely five generations ago. Many chemicals accumulate in greater quantities at each successive stage of the food chain. Since human beings are at the top of the food chain, the concentrations in our bodies are extremely high. Natural selection hasn't prepared our bodies to process these compounds. These concentrations build up over time in our tissues, and are then transmitted to our children.

Speaking of our children, the earlier and more pervasive the disruption, the more deformed our subsequent development will be. As the authors point out on their website, "a fetus and a growing child are still developing the hormonal relationships that define the endocrine system. Their organ systems are acutely sensitive to hormonal signals, which guide their development to maturity. If the wrong hormonal signal arrives at a crucial moment in development—wrong because it is disrupted by contaminants—development may be forced along pathways that diminish the child's ultimate growth potential and his or her ability to function as an adult. Adults, having already passed those crucial moments, are no longer vulnerable to the same disruptions." Unfortunately, those few chemicals that are tested for their endocrine-related effects are usually tested only for their effects upon adults, rather than upon children or fetuses.

If human endocrine systems are undergoing significant disruption, we should be seeing evidence of this in our bodies and behaviour. This evidence appears to be presenting itself. Sperm counts in developed countries appear to be falling, a phenomenon that may be contributing to the declining birth rates in those countries. They don’t seem to be falling in the developing world, where chemical saturation levels are far lower. Evidence is emerging that testicular dysgenesis syndrome (TDS), a condition that generates specific errors during the development of fetal testes, is responsible for these declining sperm counts and for rising incidences in the developed world of hypospadias (a deformity in which the opening of the penis is shifted from the head to somewhere along the shaft), cryptorchidism (a condition in which the testes fail to descend into their normal position in the scrotum by 12 months of age), and testicular cancer. In women, endometriosis rates appear to be higher now than they were in the mid-twentieth century. Girls in the United States are reaching puberty at an increasingly early age. This is exactly what we should expect in an environment that’s heavily contaminated by endocrine disrupters.

Most troubling, perhaps, is the effect these disrupters are likely having on our neurological development. Rates of autism in the developed world appear to have doubled since the 1980s. Learning disabilities, behavioural problems, and attention deficit hyperactivity disorder also appear to be becoming more frequent. The effects of endocrine disruptors on our collective emotional intelligence are probably quite severe, but it doesn’t stop there. Some studies have suggested that the contaminants already present in our environment could harm our mental development enough to cause a 5-point loss in measurable IQ scores in the population.

This might not sound like much but, as Our Stolen Future points out, the effects would be significant. “With average IQ scores of 100, a population of 100 million will have 2.3 million intellectually gifted people who score above 130.” If the average were to drop five points to 95, “Instead of 2.3 million, only 990,000 would score over 130, so this society would have lost more than half of its high-powered minds with the capacity to become the most gifted doctors, scientists, college professors, inventors, or writers. At the same time, this downward shift would result in a greater number of slow learners, with IQ scores around 70, who would require remedial education . . . and who may not be able to fill many of the more highly-skilled jobs in a technological society.”

The social implications of this mental impairment for families, communities, and nations would be catastrophic. We’re hitting peak oil, our climate is destabilizing, two-thirds of our planet’s vital ecosystems are at serious risk, and our technological capacity to destroy ourselves is growing by the hour. In the face of these problems, how can we afford to further jeopardize our emotional stability or our already inadequate intellects?

As bad as things are, they’re probably going to become immeasurably worse. We’re adding a thousand new chemicals to the stew each year, industry is growing throughout the developing world, and our corporate rulers are tearing down whatever flimsy environmental protections we erected in recent decades.

While you’re pondering this, remember that amphibians and human beings take up only a small portion of our global ecosystem. Every animal with an endocrine system is affected by these disrupters. With infinite stupidity we’re disorganizing the chemistry of the entire biosphere.

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