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Public Radio's Environmental News Magazine (follow us on Google News)

September 9, 1994

Air Date: September 9, 1994

SEGMENTS

Dangerous Dioxin: An Update

Host Steve Curwood previews a forthcoming 2,000 page E.P.A. report on the harmful effects of dioxin. The new research compiled by hundreds of scientists contains findings which suggest that dioxin is even more hazardous than previously thought. Others, in the chlorine industry, say there is no need to be alarmed. (07:05)

Is the Tijuana River Half Full, or Half Empty? / Bebe Crouse

San Diego County, California has experienced beach closings due to raw sewage outflow from Mexico. Reporter Bebe Crouse visits a prototype sewage plant which treats sewage as a resource rather than a problem. It's being offered as an alternative to a massive treatment plant, towards which the US Government is contributing half a billion dollars. (05:38)

The Bucks Stop Here / David Catlin

Commentator David Catlin tells us why, even as a loyal Missourian who respects Harry S. Truman, he thinks a national park in the late president's honor seems like misspent funds. Catlin feels national park dollars would be better spent on our many declining trails and dispirited old faithfuls. (03:20)

The Listeners Have Their Say

We hear listener comments concerning our recent three-part population series covering a broad range of topics including immigration, illegal abortion and patriarchy. (05:15)

Show Credits and Funders

Show Transcript

Copyright (c) 1994 by World Media Foundation. No portion of this transcript may be copied, sold, or transmitted without the written authority of World Media Foundation.

HOST: Steve Curwood
NEWSCASTER: Jan Nunley
REPORTERS: Stephanie O'Neill, Bebe Crouse
COMMENTATOR: David Catlin

(Theme music intro)

CURWOOD: From National Public Radio, this is Living on Earth.

(Music up and under)

CURWOOD: I'm Steve Curwood.

How dangerous is dioxin? Some call it the world's most deadly pollutant; others say its dangers have been overrated. Now a new EPA study says dioxin is even more hazardous than had been thought.

SCHWARTZ: The current background levels of dioxin are not that far removed from the levels at which we are already seeing harmful effects. This is not some problem that we might face in the future. This is a problem that we're already facing now.

CURWOOD: Also, the US plans to spend millions to clean up waste water from Tijuana, Mexico. But a local engineer has built a pilot plant that he says is cheaper and better.

DE LA PARRA: It's very low technology. This is very low energy. Low cost. Reliability. This has never broken down in 2 years of operation.

CURWOOD: This week on Living on Earth, coming up right after this news.

Environmental News

NUNLEY: I'm Jan Nunley with this summary of environmental news. The CIA says efforts by Iraqi president Saddam Hussein to rid his country of rebels has created an environmental disaster in Iraq's southern marshlands. An agency report says Hussein ordered almost 2,000 square miles of wetlands drained, so that Iraqi troops and tanks could pursue insurgents hiding out there. The report says Iraq used a dam and a canal to divert waters from the Tigris river and turned once rich marshlands into desert, driving almost 100,000 rebels across the border into Iran. Baghdad claims it was trying to create farm land in the region.

DNA tests indicate Japan may be illegally harvesting or importing several species of whales. Researchers involved in a pilot study to determine the usefulness of DNA tests in tracking whaling violations identified 4 different types of whale meat on store shelves in Japan. But under international law only one should have been there: the southern hemisphere minke whale. Researchers writing in the journal Science say the rest came from whales that are either illegal to hunt or were not reported by Japan to the International Whaling Commission as required by treaty. The meat purchased in Japan by whale conservationists included a sample from a humpback whale protected around the world since 1967. Dr. Scott Baker of the University of Auckland in New Zealand conducted the test.

BAKER: Our intent had been to test a system that we thought would be effective for this type of monitoring. It hadn't been intended as a sting; it certainly was a very limited operation. But we felt we did demonstrate that it's potentially effective.

NUNLEY: Baker presented his findings to the International Whaling Commission, which is considering DNA testing as a monitoring tool. An official at Japan's Washington Embassy says he hasn't seen the Science report, but the whales could have been caught before the current moratorium, since it's not unusual for whale meat to be stored for many years.

A black market for CFCs may be slowing the transition to ozone-friendly coolants. England's Financial Times reports that many big companies have adapted cooling systems to handle new refrigerants mandated by an international treaty. But an executive of a British company which makes a substitute chemical says many smaller firms won't pay the price to convert. Michael Harris, an executive of the chemical giant ICI, says thousands of tons of CFCs are finding their way into western Europe, probably from eastern Europe or Asia. He called on governments to step up monitoring of the CFC phase-out.

For the first time a shrimp industry group in Texas is offering a reward for tips on the deaths of endangered sea turtles. It matches a similar prize from the Federal Government offered after turtle deaths increased 4-fold this year along Texas coast. Federal officials say intensive patrolling has cut turtle deaths, but up to 5% of shrimpers still don't use the required turtle excludedrdevices. Officials also say pollution may be playing a part in this year's record toll of dead turtles.

Don't eat fatty foods and don't breathe them, either. That's the word from southern California clean air officials who are moving to cut air pollution from restaurant kitchens that grill or fry meats. As they try to get auto and factory emissions under control, clean air officials say less obvious sources of air pollution are also part of the problem. From Los Angeles, Stephanie O'Neill explains.

O'NEILL: Southern California restaurants spew out 33 tons of pollution every day. That's the same amount of hydrocarbons emitted from oil refineries in the area, and 9 times more soot particles than is produced by all the buses in the region. The proposal by the South Coast Air Quality Management District would require restaurants that cook more than 50 pounds of meat and 25 pounds of other foods each day to cut the emissions from their charbroilers, griddles, and deep fat fryers. But owners of fast food chains that serve high volumes of burgers say finding the technology to meet those emissions standards may be difficult and expensive. The plan, which is thought to be the first of its kind in the nation, could take effect by next year and would join other clean air standards in the region that, among other things, regulate emissions from bakeries, as well as charcoal and starter fluids used in backyard barbecues. For Living on Earth, I'm Stephanie O'Neill in Los Angeles.

NUNLEY: Fears that the world's last mountain gorillas would be wiped out in the Rwandan civil war apparently haven't come true. Some observers worried that refugees fleeing the bloodshed would either kill the gorillas for food or destroy the primates' habitat. But wire service reports say park officials in neighboring Zaire report only one gorilla fatality, and that the Rwandan park rangers who fled during the massacre have already contacted the new government about returning to work. There are only about 600 mountain gorillas remaining in the world, all in protected habitat in Rwanda, Zaire, and Uganda.

Meanwhile, the London Observer reports that a group of scientists has petitioned the United Nations to issue a human rights declaration for gorillas and other apes. The declaration would guarantee life, liberty, and freedom from torture to our closest animal relatives.

That's this summary of environmental news. I'm Jan Nunley.

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(Theme music up and under)

Dangerous Dioxin: An Update

CURWOOD: This is Living on Earth. I'm Steve Curwood. Dioxin has been called the most toxic chemical compound ever produced. The presence of tiny amounts has been enough to empty entire towns. And for many environmental activists, it's Public Enemy Number One. But in recent years, some scientists and interested businesses have questioned the dangers of dioxin, claiming that public fear of the substance and government efforts to eliminate it are overreactions. Now, a new draft report by the Environmental Protection Agency is reaffirming the dangers of dioxin, and suggesting that it could be even more harmful than had been thought. And it contains a chilling warning. It says that many of us may already harbor enough dioxin in our bodies to affect our health. Possible problems, the draft says, range from cancer to reducing our ability to fight disease, to disrupting our ability to have healthy children.

BIRNBAUM: Levels that are fairly close to levels that the average person in the US or in Europe or in Canada might have in their bodies are very close to the levels where adverse effects have actually been reported in experimental animals, and even in some human studies.

CURWOOD: Linda Birnbaum is Director of Environmental Toxicology at the Health Effects Research Laboratory of the EPA, which has just completed a 3-year reassessment of dioxin. Hundreds of scientists were involved in producing the 2,000-page document. The findings are dramatic. Dr. Birnbaum says the report affirms the risk of cancer from exposure to dioxin. But it goes much further. It suggests, for instance, that minute amounts of dioxin, its chemical relatives, and related compounds like furans and PCBs, may cause a drop in the male hormone testosterone, which is necessary for normal sexual development. Other possible effects include the aggravation of age-related diabetes and the weakening of our ability to fight diseases.

BIRNBAUM: It's clear that we need to pay more attention to these non-cancer effects. Some of the effects that we're seeing in experimental animals at levels that are not very different from the background level in the population are effects on the immune system and effects on the developing reproductive systems.

SCHWARTZ: That's, I think, the most intimidating piece of the reassessment.

CURWOOD: Joe Schwartz is Director of Policy for the group Physicians for Social Responsibility.

SCHWARTZ: What this reassessment shows is none of us, whether we live in a major city, whether we live near a factory, whether we live in the North Pole, we've been exposed to dioxin in the environment. And the current background levels of dioxin are not that far removed from the levels at which we are already seeing harmful effects. This is not some problem that we might face in the future. This is a problem that we're already facing now.

CURWOOD: But Bill Carroll of the Chlorine Chemistry Council says we should not be alarmed.

CARROLL: It's not an emergency, it's not time for panic in the streets. It's time for some serious evaluation and some work on the problem.

CURWOOD: Dr. Carroll's industrial employers are especially interested in the EPA's reassessment of dioxin. Dioxin is produced as a by-product in many industrial processes which use chlorine, especially the manufacture of paper products. Chlorine is also used in making pharmaceuticals and plastics. Dr. Carroll calls the EPA's reassessment important, but says it's too early to draw conclusions from it.

CARROLL: Most of this stuff is very new, and most of the study of the effects is very new. And so there's probably more that we don't know about this than what we do. What we're relatively sure of, I think, is that the dose still makes the poison.

CURWOOD: In other words, Dr. Carroll says, it's the exposure level that's key. But Linda Birnbaum of the EPA says government scientists have found biological effects of dioxin even at the smallest detectable levels.

BIRNBAUM: These can be very, very potent chemicals. And you don't need much of a potent chemical to bring about an effect. The amounts, for example, which are currently regulated in fish or food supplies are in the parts per trillion range.

CURWOOD: But Bill Carroll of the Chlorine Chemistry Council says there may be a difference between finding a biological response in the laboratory and an actual health risk in people.

CARROLL: The discussion that the EPA has is that they feel that doses that are as small as they can measure show some biochemical response. Whether that response is harmful or not is another story.

CURWOOD: So, no matter how small the dose, there is a biochemical response to dioxin.

CARROLL: That's what the EPA suggests. But whether there is a direct cause and effect relationship at low doses to those effects is still unshown.

CURWOOD: One of the reasons for the hair-splitting on the cause and effect is that the EPA assessment of dioxin uses a relatively new and controversial method of calculating its risk. It's called TEQ, the Total Equivalency Approach. Traditionally, the EPA determines the hazards for one chemical at a time. But since there are dozens of chemicals with dioxin-like properties, Linda Birnbaum of the EPA says the report deals with them as a group.

BIRNBAUM: That's one of the major new steps in this risk assessment. That instead of looking at a single chemical, we are looking at a family of chemicals. And we are basically saying that if there's concern with one, there needs to be concern with all. Since they all do the same thing. Basically, some of these other compounds are really dioxins in disguise. Very few of them are as toxic as dioxin; but while some of them aren't as toxic as dioxin, there may be a lot more of them out there in the environment.

CURWOOD: Scientists believe that the banning of dioxin-like PCBs, tighter pollution controls, and changes in manufacturing processes, have already cut dioxin production over the last 20 years. But the draft EPA report is likely to prompt a new round of calls for tighter restrictions, or even outright bans on dioxin. For now, EPA officials will open the document up to public comment and scientific review over the next few months. Any new regulations that do emerge would likely focus on getting dioxin out of our food. It's estimated that 95% of our exposure to dioxin comes from what we put in our mouths. It accumulates in the food chain and becomes more concentrated at every step. Even if it's too early for the government to make new recommendations, Joe Schwartz of Physicians for Social Responsibility says there are things people can do to minimize the dangers of dioxin. Chief among them is cutting down on fat.

SCHWARTZ: Reducing the amount of fat in people's diet would be a good idea, because fat is where dioxin bioaccumulates in the environment. And reductions in fat in the diet should have some impact on reducing the average human's exposure to dioxin from the food chain.

CURWOOD: The final version of the EPA's dioxin reassessment is scheduled to be released next spring.

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(Music up and under)

Is the Tijuana River Half Full, or Half Empty?

CURWOOD: San Diego County in California has been plagued in recent years with beach closings stemming from untreated sewage that flows north from neighboring Tijuana, Mexico. US officials are working with their Mexican counterparts to build a massive sewage treatment plant to address the problem, but as Bebe Crouse reports from Mexico, there may be a more effective and more affordable way.

CROUSE: It's a brilliant blue sky day at Imperial Beach, a long stretch of sand just north of the Mexican border. But despite the weather, the beach is virtually empty. That's because the ocean here is unfit for swimming due to colIform contamination. Dave Schlesinger is director of San Diego's Metropolitan Waste Water Department.

SCHLESINGER: Last year, the summer of 1993, the beaches were quarantined for over 200 days, and now this is a major impact upon the tourism, the business of the coastal beach cities. But even more important than that, it's a health issue.

(Sound of running water and traffic)

CROUSE: Part of the problem is simply geography. At the boundary between Tijuana and San Diego, a broad coastal plain rises up into steep hills on the Mexican side. The water from those hills drains into the Tijuana River, which, oblivious to fences and customs agents, reaches the ocean on the US side of the border. And since perhaps 50% of the homes in Tijuana are not connected to sewers, much of what the river brings north is raw sewage.

JACOBS: This is Stewarts Drain, and this is what we call Stewarts Bridge, and this is a natural drainage from Mexico into the US. So when it rains...

CROUSE: Chuck Jacobs is an engineer with the International Boundary and Water Commission, the IBWC. And what he's pointing to is a stream of murky water flowing from beneath a busy street that skirts the Tijuana side of the international border. As the smelly rivulet dumps into the US, it's channeled toward a concrete pipe.

JACOBS: This pipe does not come to the US; it goes toward Mexico. This is one of our defensive works areas, and we collect the sewage, the minimal renegade flows that come across here.

CROUSE: Through a system of pipes and pumps, the IBWC tries to capture this so-called renegade sewage and send it back south to a Mexican sewage treatment plant. But that plant often operates at capacity. And when it rains, both it and the IBWC'S elaborate defenses break down and raw sewage spills into US waters. After years of haggling over the problem, both countries agreed to build a binational sewage treatment plant on the US side of the border, with an ocean outfall off the San Diego coast. And though it's still unclear how much Mexico will chip in, the US share of the project cost is nearly half a billion dollars.

DE LA PARRA: Government thinks that throwing money will be the solution to pollution.

CROUSE: Tijuana-based engineer Carlos De La Parra thinks that money could be better spent. For a fraction of what the big binational plant will cost, De La Parra's team has built a small scale alternative plant that not only treats Tijuana sewage but has the added benefit of reclaiming the water and using it to irrigate the city's drought-plagued hillsides.

(Sound of water sprinklers)

CROUSE: Instead of a centralized system in which sewage is pumped for miles, and at considerable cost, to a massive treatment plant, De La Parra advocates a series of smaller, less costly local plants like this prototype.

DE LA PARRA: This is raw sewage coming in.

CROUSE: This is a passive system of filters and clarifiers with virtually no moving parts and hardly any need for maintenance.

DE LA PARRA: It's very low technology. This is very low energy. Low cost. Reliability. This has never broken down in 2 years of operation. We must be breaking a record in terms of wastewater treatment plants in developing nations.

CROUSE: Aside from claiming the treated water, solid waste is composted and used at a small greenhouse and nursery on the site. And plans don't stop there.

(Footfalls on gravel, birdsong)

DE LA PARRA: These are the future wetlands.

CROUSE: Artificial wetlands will further cleanse the water to a level that De La Parra hopes will make it safe enough for swimming and showering. At the very least, the water could help reforest the barren city and stop severe erosion.

DE LA PARRA: The key question is, right at the start, is sewage a problem or is it a resource?

CROUSE: So far, the people dealing with Tijuana's sewage see it only as a problem. Washington and Mexico City have rejected the idea of reclamation as too expensive. But they're only looking at part of the balance sheet. It's the city of Tijuana that has to buy the water in this parched region, and De La Parra says they see the project differently.

DE LA PARRA: Because they have to pay the state to use the water to irrigate the urban greenery in the city. We can sell the water at half the price. That attracts their attention.

CROUSE: Calls to the city went unreturned but De La Parra says Tijuana's mayor has agreed to buy some of his reclaimed water. In a city whose population has quadrupled in a little more than a decade, the demand for both water and sewage treatment will only increase. And in time, De La Parra believes the city and Mexican government will come to see these small plants as a logical way to meet both those demands and help solve a problem with its neighbors in San Diego. For Living on Earth, this is Bebe Crouse in Tijuana, Mexico.

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(Music up and under)

The Bucks Stop Here

CURWOOD: If you had a chance to visit one of our US national parks this summer, you may have found the facilities overtaxed by the crowds. Commentator David Catlin has some pointed thoughts as to why.

CATLIN: Missourians revere Truman as an almost mythical figure, right up there with Mark Twain and George Brett. So the neighbors hereabouts are shocked at my reaction to this development involving his house. I think it stinks. I think it stinks because our existing national parks are coming apart at the seams, and the last thing their managing agency needs is to spend its meager monies on another pet project of local boosters who have the ear of their Congressman.

Ironically, about the same time the Truman transaction hit the news, the National Parks and Conservation Association released the results of a survey of national park superintendents. The word was uniformly gloomy. The condition of park infrastructures - the roads, trails, visitors' centers, bathrooms, and other basic facilities - was given Cs and Ds virtually across the board.

So I don't believe we should be spending money on anything as dubious as Truman's Grandview home. Now don't get me wrong; I think Truman was a great guy, too. But how many of his lodgings rate as national treasures? We already own one: the Harry S. Truman National Historic Site in Independence, Missouri. Other Truman memorabilia worth saving is protected, as it should be, by local entities. His birthplace in Lamar, Missouri, is a state historical site. The privately-administered Truman Library in Independence houses his artifacts and papers. And the Grandview home was, until now, run by the county.

I think the memory of Harry Truman is already pretty well provided for. But this is park barrel politics, and it's nothing new. Call me a purist, but it saddens me to think that places like Gateway National Recreation Area, Steam Town National Historic Site, and the Thaddeus Kosciusko National Memorial, are sucking up Federal tax money while Yosemite, Grand Canyon, and Gettysburg go begging.

And how much is Truman's Grandview house going to cost? Nobody has the exact figure yet, but there will be inspection dollars and research dollars and restoration dollars, and dollars to staff the place and et cetera. Compared to the national debt, this may not seem like a lot of money. But it would repair plenty of gullied trails in the Smokies, or replace the archaic plumbing in the Badlands.

So, if you flatten a tire or lose a hub cap in a national park pothole, don't jump the superintendent. He didn't have the funds to fix it. Why not? The answer may be found in my home state of Missouri. The bucks stopped here.

CURWOOD: Commentator David Catlin is a naturalist who worked for the National Park Service for 6 years. His comments come to us from member station KSMU in Springfield, Missouri.

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The Listeners Have Their Say

CURWOOD: We received a great deal of response to our recent programs on population issues. Our features on the debate over the environmental impact of immigration to the United States and our own high teen birth rate brought a number of calls including these.

CALLER: My name is Major Tillman. I'm calling you from El Paso, Texas. I certainly echo the comments that we don't need to consume 5, almost 6 times more resources per individual in the United States than persons who live abroad. I think we have space and time to share. We just need to look at the best ways to do that. Thanks.

CALLER: I think we should begin at once both to limit immigration and to severely control our own population growth. We need to reintroduce fear, guilt and shame to our teenage population to have a child out of wedlock. At the same time we can begin to put people, immigrants, at the top of the list if they will have themselves vasectomized or undergo tubal ligation.

CURWOOD: Chris Curry wrote us over the Internet, calling for a national discourse on population. And for more encouragement for those of us who decide not to have children. And a listener to Maine Public Broadcasting had this suggestion.

CALLER: The current tax system and Welfare system favors having more and more children. What policy makers must do now is to end that free lunch. Tax deductions should only be allowed for up to 2 children in a family, and thereafter the third, the fourth and the fifth child in the family shouldn't be allowed a tax deduction unless those children are legally adopted.

CURWOOD: Our phone lines were jammed after our interview with Tufts University professor Pat Hynes on the role of patriarchy in the population question. We received this call from a listener to Oregon Public Broadcasting.

CALLER: Hi, this is Amy Curry. I certainly do believe that the key to solving the ecology problems of the Earth is the feminist revolution. And the reason for that is that as we empower women and girls, they will not need to worry about whether their children will survive, and they won't have to define themselves by having children. And every country where the women and girls are empowered in that way, the population is leveling off.

CALLER: Hi, my name is Scott Newland, from Albuquerque, New Mexico. I listen to you on KUMN. Regarding the impact of men on world population, I think she's absolutely right. Given that men control the institutions primarily throughout the world, they are the ones that have to answer for the population expansion. The fact that poor people think they have to have more children in order to ensure their own survival is sad testimony to the inequitable resource distribution across the world.

CURWOOD: And we got a number of calls from men who were angry about our interview with Professor Hynes. This one came from Davenport, Iowa, from a listener to WVIK.

CALLER: Hello. That woman who was blaming men for reproduction? She's dead wrong and she knows it, and she's using the big lie technique. The truth of the matter is that female of any mammalian species (laughs) would have control, not the male, except in cases of rape. She's so crazy that, you know, what can you do but laugh, which is I suppose cry.

CURWOOD: And this from a listener to KPBX in Spokane, Washington.

CALLER: I traveled in Mexico in the 70s. A man took me aside and asked me what I could tell him about birth control. He and his wife had 8 children; he wanted to know what American women knew that helped them prevent having children. Now there's men out there who are interested in this, and I hope they will speak up. Thank you.

CURWOOD: Finally, we asked listeners whether they thought high consumption in the rich countries, or booming population in the poorer countries, was more of a threat to the future. Michael Bertsch, who listens on KCHO in Chico, California, sent an e-mail message saying it was a ridiculous question. "We in the north must reduce our consumption," Mr. Bertsch writes, "and those in the south must reduce population growth. Plus, we in the north must show the south how our consumption patterns have caused great hardship, so they can industrialize sustainably. And those in the south must show us in the north how to live happily and comfortably on less. Only then can we call ourselves civilized.

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(Music up and under)

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Living on Earth is a project of the World Media Foundation, and recorded at the studios of WBUR, Boston. I'm Steve Curwood, executive producer.

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