Dear EarthTalk: Is it true that coastal development contributed to greater loss of life from the Indian Ocean tsunami disaster?
— James McClain, New York, NY
The tsunami that devastated Southeast Asia in December was a natural catastrophe triggered by a massive undersea earthquake. But rampant coastal development in recent years—which removed the mangrove forests and coral reefs that had previously been abundant along shorelines—did contribute to the damage and death toll. These natural barriers formed a so-called "coastal greenbelt" that served as both nursing grounds for fish and sea mammals and as buffers against the pounding surf and occasional tidal wave.
Thailand's popular and extensively developed beach resorts were some of the hardest-hit areas in the tsunami zone. In these especially vulnerable areas, hotels, shrimp farms, highways, housing and commercial developments have squeezed out the natural barriers that might have otherwise shielded many victims from the brunt of the deadly wave.
Edward Barbier, a University of Wyoming professor who has studied resource problems in developing countries for more than two decades, points out that explosive economic development since the 1960s has depleted half of Thailand's coastal mangrove forests. "Even nature's ecosystem could not have prevented the tsunami," concedes Barbier. "With an event that huge you have to expect great loss, but the question is, could some of it have been reduced?"
According to Meena Raman of Friends of the Earth International, tens of thousands of lives were spared by December's tsunami directly because of coastal conservation measures instituted in India, Malaysia and Sri Lanka to preserve mangrove forests and coral reefs. "What we have seen in the tsunami crisis is that the areas that were protected naturally suffered less than those that were more exposed," says Raman, adding that the protection of such natural walls may be the only long-term solution to defending coastal populations against future tidal waves.
Going forward, coastal communities in Southeast Asia and elsewhere are likely to suffer further from an even greater man-made environmental problem: global warming. According to the Intergovernmental Panel on Climate Change (IPCC), an association of climate scientists that reviews and reports on the latest findings about climate change, sea levels have risen worldwide about six inches over the last century as a result of the industrial pollution that has warmed the globe. Many in the environmental community believe that a higher sea level overall also intensified the effect of the tsunami on the affected coastal communities.
IPCC scientists expect that we may see an additional sea level rise of a foot or more over the next several decades as polar ice caps melt in response to rising global temperatures—a trend that is certain to have much longer-term negative effects on coastal communities and their inhabitants.
Dear EarthTalk: Are metals poisonous, and what is "Toxic Metal Syndrome?"
— Dan Galt, Hughson, CA
Many metals, including aluminum, mercury, lead, iron and cadmium, can have a number of disturbing effects on human beings. The phrase "Toxic Metal Syndrome" encompasses all of the health problems associated with such metals.According to the book, Toxic Metal Syndrome, by Dr. H. Richard Casdorph and Dr. Morton Walker, exposure to metals causes cell damage as the substances collect in organs, resulting in "degenerative diseases which affect no less than 92 percent of the populations of Western industrialized nations, in particular those people living in apartment high-rises and other polluted city dwellings." The book goes on to detail how some of the diseases linked to poisonous metals include heart and/or blood vessel deterioration, pancreatitis, gout, arthritis, chronic fatigue, irritable bowel, multiple sclerosis and several forms of cancer.
One of the most dangerous metals to human health is aluminum, a potent "neurotoxin" that can cause cognitive impairment as well as osteoporosis and kidney malfunction. Some studies show that people with Alzheimer's disease have more aluminum than usual in their brains. But, according to the U.S. Agency for Toxic Substances and Disease Registry (ATSDR), it is unknown whether the metal causes Alzheimer's or if the buildup happens to people who already have the disease.
Meanwhile, mercury is also very poisonous. Mercury is a by-product of many industrial emissions, and as a result can end up in rivers, streams and oceans and—by extension—the fish we eat. Mercury can also be released into the body in small amounts from so-called "silver fillings" in teeth (which contain mercury) and from some medical treatments. ATSDR reports that mercury can affect many different areas of the brain and their associated functions. It can also cause cardiovascular and immunological problems. Research indicates that some people who eat fish contaminated with large amounts of mercury can develop permanent brain or kidney damage. Casdorph and Walker caution that mercury can also cross the placenta and affect a developing fetus.
Since their bodies and brains are still developing, children are disproportionately affected by exposure to toxic metals. Many toxic metals have been documented to cause developmental delays, learning disabilities, depression and behavioral abnormalities in many otherwise normal-appearing children. Researchers have found that more than 20 percent of children in the U.S. have had their health or learning adversely affected by exposure to toxic metals such as mercury, lead and cadmium.