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Depleted uranium contaminates Bosnia-Herzegovina
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Experts debate risk of eating fish containing mercury
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ENVIRONMENT BRIEFS
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Insects thrive on GM ‘pest-killing’ crops

By Geoffrey Lean

Mar. 30— Genetically modified crops specially engineered to kill pests in fact nourish them, startling new research has revealed.

The research — which has taken even the most ardent opponents of GM crops by surprise — radically undermines one of the key benefits claimed for them. And it suggests that they may be an even greater threat to organic farming than has been envisaged.

It strikes at the heart of one of the main lines of current genetic engineering in agriculture: breeding crops that come equipped with their own pesticide.

Biotech companies have added genes from a naturally occurring poison, Bacillus thuringiensis (Bt), which is widely used as a pesticide by organic farmers. The engineered crops have spread fast. The amount of land planted with them worldwide grew more than 25-fold — from four million acres in 1996 to well over 100 million acres in 2000 — and the global market is expected to be worth $25 billion by 2010.

Drawbacks have already emerged, with pests becoming resistant to the toxin. Environmentalists say that resistance develops all the faster because the insects are constantly exposed to it in the plants, rather than being subject to occasional spraying.

But the new research — by scientists at Imperial College London and the Universidad Simon Rodrigues in Caracas, Venezuela — adds an alarming new twist, suggesting that pests can actually use the poison as a food and that the crops, rather than automatically controlling them, can actually help them to thrive.

They fed resistant larvae of the diamondback moth — an increasingly troublesome pest in the southern US and in the tropics - on normal cabbage leaves and ones that had been treated with a Bt toxin. The larvae eating the treated leaves grew much faster and bigger — with a 56 percent higher growth rate.

They found that the larvae “are able to digest and utilize” the toxin and may be using it as a “supplementary food,” adding that the presence of the poison “could have modified the nutritional balance in plants” for them.

And they conclude: “Bt transgenic crops could therefore have unanticipated nutritionally favorable effects, increasing the fitness of resistant populations.”

Pete Riley, food campaigner for Friends of the Earth, said last night: “This is just another example of the unexpected harmful effects of GM crops.

“If Friends of the Earth had come up with the suggestion that crops engineered to kill pests could make them bigger and healthier instead, we would have been laughed out of court.

“It destroys the industry’s entire case that insect-resistant GM crops can have anything to do with sustainable farming.”

Patrick Holden, director of the Soil Association, said it showed that GM crops posed an even “worse threat to organic farming than had previously been imagined.” Breeding resistance to the Bt insecticide sometimes used by organic farmers was bad enough, but problems would become even greater if pests treated it as “a high-protein diet.”

Source: Independent (UK)

Depleted uranium contaminates Bosnia-Herzegovina

Sarajevo, Bosnia-Herzegovina, Mar. 25 (ENS)— For the first time, a United Nations research team has confirmed that depleted uranium from weapons used in Bosnia and Herzegovina in 1994 and 1995 has contaminated local supplies of drinking water, and can still be found in dust particles suspended in the air. Depleted uranium is used in armor-penetrating military ordinance because of its high density, and also in the manufacture of defensive armor plate.

A new report released here today by the United Nations Environment Program (UNEP) records the first instance of depleted uranium (DU) contamination of groundwater, which was found at one site.

“The findings of this study stress again the importance of appropriate cleanup and civil protection measures in a post-conflict situation,” said Pekka Haavisto, chairman of the UNEP DU projects. “We hope that this work will play a role in protecting human health and the environment in the unfortunate event of future conflicts.”

For the rest of this article, please see www.ens-news.com.

Experts debate risk of eating fish containing mercury

By Stephen Leahy

Windsor, Canada, Mar. 26 (IPS)— One in 12 North American women have enough mercury in their bodies to produce cerebral palsy, impaired memory, and developmental delays in their unborn children, but scientists gathered here recently agreed those results should not stop people from eating fish — the main source of mercury in food.

A recent study found that some people in San Francisco, California who ate fresh fish — sushi in particular — three or four times a week developed numb hands, experienced hair loss and had children who were developmentally delayed, said David Carpenter, a professor of environmental health and toxicology at the University of Albany in New York state.

“They were suffering from Minamata disease,” said Carpenter. The disease, which is actually mercury poisoning, was first identified in 1955 when people in Japan’s Minamata Bay consumed fish with high mercury concentrations due to local industrial sources.

Mercury is a potent neurotoxin and the people of Minamata Bay suffered blindness, paralysis, loss of muscular control, birth defects, and more than 1,400 deaths.

The afflicted Californians had been eating fresh tuna, swordfish, king mackerel, and shark, all of which have high levels of mercury.

Other people around the world suffer mercury poisoning. Some living along the Tapajos River in Brazil’s Amazon Basin have suffered neurological impairment from eating fish from their river with high concentrations of mercury.

In Greenland, where levels of the metal in ringed seals and beluga whales have quadrupled in 25 years, 16 percent of people have mercury levels above the toxic threshold.

Medical experts agree that fish is one of the healthiest foods — loaded with protein and heart-healthy Omega 3 fatty acids. There is no question that fish can help prevent heart disease, Carpenter agrees, but fish containing mercury can negate those benefits depending on how badly they are contaminated.

Mercury is a naturally occurring metal found in cinnabar, and low levels of it seep into the environment from rocks and soils, and in volcanic eruptions. The use of mercury in thermometers, dental fillings, fluorescent light bulbs, vacuum gauges, some pharmaceuticals, vaccines, and older batteries, along with industrial wastes from mining, cement kilns, the manufacture of chlorine, and coal power plants have added tens, if not hundreds of thousands of tons of mercury to the global environment.

A United Nations Environment Program (UNEP) report released last month found 70 percent of mercury emissions of human origin come from the burning of coal and the incineration of waste, annually pumping 1,500 tons of the metal into the environment.

Technologies are available to reduce mercury emissions from power stations by about 80 percent but they are costly, added the report, “Global Mercury Assessment.” But UNEP urged governments to introduce drastic mercury reduction programs.

Mercury is an element, so it does not disappear or break down. Moreover, mercury particles are easily transported by air currents thousands of miles from where they were produced. As a result, virtually all fish contain traces of the metal.

Fish pick up methyl mercury, a form of the element that binds to the protein in their bodies, from microorganisms in oceans and lakes. As big fish eat little fish, they absorb the methyl mercury in their prey so that larger older fish, such as swordfish, shark, and tuna, carry more of the metal than other species like salmon and shrimp.

In February, the US Environmental Protection Agency (EPA) reported that eight percent of all US women of childbearing age — five million in all — had mercury levels high enough to potentially cause learning disabilities, including reduced IQ and problems with motor skills, in their unborn children.

The EPA recommends that women and children under the age of six limit their fish consumption and avoid certain species entirely.

“While there is more and more evidence that at low doses mercury has subtle effects on a developing child, we have to be very careful about the real risks mercury poses,” said Laurie Chan, associate professor at McGill University’s Center for Indigenous Peoples’ Nutrition in Montreal. “We don’t want people to get the message that they shouldn’t necessarily eat less fish.”

Public health officials have long recommended eating two meals of fish a week but most North Americans do not consume that quantity.

It is particularly important for aboriginal people in northern Canada to continue to eat fish and other wild foods, added Chan, because the switch in their diets from traditional foods to market-based ones has been much more hazardous to their health.

Skyrocketing rates of diabetes and heart disease are just two of the health impacts. “Market-based diets are a lot worse for aboriginals than eating fish or marine animals containing mercury or PCBs,” according to Chan.

But they should minimize their exposure to contaminants by choosing species and the parts of the fish or animal that have the lowest contaminant levels, she added.

The general public should take a similar approach towards the fish they eat, Chan said. “The real issue for mercury is what fish and where?”

In North America, mercury levels in fresh-water fish are measured annually and warnings or fish advisories are issued. Nearly all large carnivorous fish, like lake trout, walleye, pickerel, and pike have high mercury levels and the advisories warn against eating them. “These can be really dangerous for children if eaten regularly and in quantity,” said Carpenter.

But there is no way to know if fish bought in stores or served in restaurants is safe. No labeling standards exist and the same fish are often given different names. “Consumers have no assurance that these fish are not contaminated,” said Carpenter.

Until proper regulations and an official guide to eating fish is in place, what should people do? Learn more about the fish you eat and apply Carpenter’s rule of thumb: “Don’t eat large carnivorous fish.” Salmon are the exception, he says, but choose wild over farmed if possible because farmed salmon contain other contaminants.