Battle Looms on Chemicals That Disrupt Hormones : Science: Research finds threats at levels once thought safe. Cleanup of DDT off Palos Verdes is part of debate.
After waiting nearly two decades to cleanse their lake-shore harbor of a million pounds of toxic waste, the people of this working-class suburb of Chicago were ready to party.
Setting sail on Lake Michigan aboard a cruise ship aptly named Celebration, local, state and federal dignitaries proclaimed the elaborate $21-million cleanup of Waukegan Harbor officially complete this summer. The marina--for years stigmatized as the PCB contamination capital of the world--was declared safe for everyone who works and plays there.
But the celebration may have come too soon.
Compelling new scientific evidence has emerged indicating that low concentrations of pesticides and industrial chemicals once thought to be harmless can alter the hormones of wild animals, confusing their sexual identities and rendering them infertile.
The threat from these decades-old chemicals--most notably massive amounts of polychlorinated biphenyls (PCBs) in the Great Lakes and DDT off the shore of Los Angeles--has stoked a long-smoldering environmental debate: How clean is clean?
For years, how much pollution to remove from severely contaminated spots has been based largely on a single target--reducing the cancer risk to humans. But that may not be enough to defend bald eagles, trout, alligators and other animals from chemicals that imitate estrogen or block testosterone in the womb. Humans who eat contaminated fish and other food harvested from these areas also could be passing subtle reproductive problems such as low sperm counts to their children.
“In spite of government regulations and testing--which we all thought was adequate in all honesty--we are now finding effects that are much more subtle and much more intergenerational than we thought,” said Tim Gross, a University of Florida endocrinologist who discovered part-male, part-female alligators and turtles in a Florida lake contaminated with DDT from a 1980 spill.
The concern over environmental hormones comes at a crucial time. In Southern California, federal officials are grappling with how to eliminate--or more likely contain--4 million pounds of the pesticide DDT dumped several decades ago in ocean waters off the Palos Verdes Peninsula.
Nationally, dozens of waterways from Washington’s Puget Sound to South Florida’s canals remain polluted with PCBs, compounds used as industrial insulators and lubricators, or DDT, even though they were banned in the United States in the 1970s.
“We have to address this enormous legacy,” said Michael Gilbertson, a biologist with the International Joint Commission, a U.S.-Canadian government panel helping guide cleanup of the Great Lakes. “How are we going to come to terms with all these dump sites? What this work on estrogens shows us is we have a very long way to go.”
Eliminating the potential for hormone-like effects is shaping up to be a political struggle.
The cost of even a basic cleanup job runs in the tens of millions of dollars and the projects take years. Expanding the scope to tackle lower concentrations of chemicals would push the price up and take even more time. Beyond that, raising new health and ecological concerns could cast a pall on a community’s businesses and recreation, especially sport fishing.
“It’s a legitimate question to ask how much it is going to cost and what are the benefits,” said John McCarthy, vice president for science and regulatory affairs at the American Crop Protection Assn., which represents Dow, Monsanto and other major pesticide producers. “I know it’s not popular to talk about economics when you’re talking about health risks, but you’ve got to get real too.”
Dealing with the legacies of the past, however, is only one contentious aspect of the battle emerging over environmental hormones.
To avoid saddling future generations with new problems, the U.S. Environmental Protection Agency and the chemical industry are wrestling with whether to restrict some of today’s chemicals. About 25 popular insecticides, herbicides and fungicides--applied on millions of acres every year in the United States--have been shown in laboratory tests to imitate estrogen or inhibit testosterone.
Included are many pesticides, such as atrazine, endosulfan, EBDCs, parathion and dicofol, that help farmers protect and grow bountiful harvests of fruits, vegetables, grains and other crops worth billions of dollars annually. Some also are widely used for eliminating garden pests and weeds.
Seven industrial compounds--such as nonylphenol, used in plastics and detergents; styrene, an ingredient of rubber; and dioxins, a widely dispersed pollutant from paper mills and other manufacturing plants--are suspected of causing problems as well.
“One of the lessons we learned from DDT is that it is very hard to correct an error once you make it,” said Dr. Lynn Goldman, assistant EPA administrator, who heads the Office of Prevention, Pesticides and Toxic Substances. “If you allow the use of a harmful compound . . . even after you take corrective action, you can see harmful effects for many years.”
Several environmental groups already are demanding a phaseout of chlorinated pesticides and other compounds, many of which are identified as man-made hormones. But manufacturers are urging the government to await clear scientific findings, which could take the National Academy of Sciences several years.
“There is a fair amount of advocacy science going on out there on this subject, and a lot of dueling Ph.Ds. Let’s take a look at the science and do this right,” said McCarthy of the crop association.
This fall, the EPA plans to propose new rules requiring manufacturers to test pesticides to determine their potential for disrupting the endocrine system that controls hormones, Goldman said. For example, manufacturers may have to check the testosterone of exposed rodents, or use a newly developed method of checking whether breast cancer cells, which are sensitive to estrogen, grow in test tubes when exposed to a pesticide.
But when it comes to non-pesticide chemicals--including some used in plastics--the government has much less authority, Goldman said. Under federal law, the EPA must first prove a chemical poses a likely public health risk before companies can be ordered to enhance testing. That, Goldman said, is a Catch-22 that could allow most industrial chemicals that alter hormones to escape tougher restrictions.
“We don’t have a very good ability to predict which chemicals are likely to be endocrine disrupters,” said Goldman, a former California epidemiologist and pediatrician. “That puts us at a great disadvantage. There are 70,000 chemicals on the inventory and of those, about 18,000 are of potential concern because they are in commerce to a significant extent.”
Today’s pesticides must be screened by their manufacturers on laboratory mice to gauge their risk of cancer, birth defects and reproductive effects. But they are not subjected to specific tests detecting hormonal changes. “Things can slip through the net,” Goldman said, “and one of those things that can easily slip through are endocrine disrupters.”
Each pesticide undergoes a “two-generation reproduction study,” which exposes rats to various doses of chemicals in their food and then examines the offspring, and their offspring. But chemical industry officials acknowledge that the test is not sensitive enough to detect all troubling side effects.
For instance, in the case of a fungicide named vinclozolin, tests by the manufacturers, BASF Corp. and Grace-Sierra Crop Protection, did not discern reproductive defects in rats. But when the EPA performed more thorough tests, it found that the fungicide blocks the formation of testosterone in rodents and that offspring were born with half-male, half-female sex organs.
Toxicologist Chris Chaisson of TAS Inc., which designs tests for chemical manufacturers, said traditional two-generation studies often cannot detect malformed genitalia because the rats are exposed to fairly low doses of chemicals. She said the search for more reliable methods “is a huge issue internationally.”
After testing pesticides, the EPA decides on a case-by-case basis whether the risk is great enough to impose new restrictions--”from changing instructions about how they are used all the way to suspension and cancellation,” Goldman said.
Manufacturers say they will not oppose new testing requirements. But they are bracing for battle if such tests lead to new bans or severe restrictions on chemicals that they say are necessary to protect the nation’s food supply from pests and weeds.
“This is not like a situation where we have to shut whole industries down because something terrible is happening to the environment,” McCarthy said. “It doesn’t mean that we should be insensitive, and it doesn’t mean we shouldn’t be vigilant. But I don’t think the environment is unraveling.”
Some pesticides have been indicted as hormone disrupters on the basis of results in test tubes or, as in the case of vinclozolin, fairly large doses fed to mice. But the true test, said pesticide industry consultant James Lamb, is to learn if the chemicals harm people or animals in amounts now in the environment, and if the risk is great enough to outweigh the benefits.
“Just because something causes a problem in a test tube doesn’t mean it poses a significant risk,” said Lamb, a reproductive toxicologist formerly with the EPA. “That kind of test is very limited.”
While a ban on all hormone disrupters is highly unlikely, some could face new restrictions or reformulation.
“We’re not going to get rid of pesticides or plastics in our society,” said David Crews, a zoologist at the University of Texas, Austin. “We will not allow loss of our quality of life. So we need to find out how to deactivate them or contain them so they don’t have these impacts.”
Generally, wildlife experts and industry agree on one point: No chemicals used today are as dangerous as DDT and PCBs, which accumulate in the environment and in body tissues and can reach poisonous levels.
“The new chemicals are entirely different,” said McCarthy of the pesticide industry group. “Most are biodegradable. That’s going to be a key difference in this whole debate.”
Although many of the nation’s waterways have improved since the banning of DDT and PCBs, wildlife officials say buildup in many harbors, rivers and other hot spots remains severe enough to maim, kill or sterilize wild animals, especially fish-eating birds.
Along many Great Lakes’ shorelines, bald eagles--a threatened species--still fail to reproduce and some cormorants are born with malformed, twisted beaks.
Beyond the political and financial ramifications, performing adequate cleanup has proved to be technically difficult.
In the case of Waukegan Harbor--on the nation’s Superfund list of toxic sites named priorities for cleanup--the EPA took 12 years to reach agreement with Outboard Marine Corp. to pay for removing 1 million pounds of PCBs the boat manufacturer had dumped into the lake in the 1960s. It took five more years for the agency to design a strategy, remove and treat some waste, and bury the rest in a boat slip walled off from the rest of Lake Michigan.
Despite the $21-million effort--which the EPA says removed 96% of the PCBs--a sister federal agency, the U.S. Fish and Wildlife Service, maintains that the water is at least 100 times too contaminated to safeguard fish and birds, including some endangered and threatened species.
“A safe level of contamination? We’re light-years away from that in any of the Great Lakes,” said David Best, a biologist for the wildlife agency’s Midwestern region who is exploring the impact of Great Lakes contamination on bald eagles. “There is no biologist that would say (Waukegan) harbor is clean enough to ensure the health of fish and wildlife.”
The EPA allowed PCBs to remain in the harbor’s sediments in concentrations as high as 50 parts per million, far greater than the 4 p.p.m. that kills a bald eagle’s eggs. The Fish and Wildlife Service recommended cleaning the harbor to a level of 0.05 p.p.m., but the EPA rejected that option as impractical.
“A lot of times EPA and state regulatory agencies feel if they get it up to human health standards, that’s enough for wildlife,” said Donald Steffeck, chief of contaminants for the wildlife service’s western region. “But those cormorants or ospreys or eagles are out there 100% of the time eating those fish.”
Returning to Waukegan Harbor to dredge more waste is considered unlikely, given the realities of money, politics and public sentiments.
Local residents generally are pleased and their harbor is more popular than ever because the water looks dramatically cleaner after the dredging and PCB concentrations have dropped. “Nobody worries about PCBs anymore,” said one local Coast Guard auxiliary officer.
“People just don’t want to know the truth,” said Charles Facemire, an environmental toxicologist with the wildlife agency. “It scares the pants off them, especially this issue of endocrine disruption and how your children could be born with reproductive problems.”
Gilbertson of the International Joint Commission said the EPA and state regulators overseeing cleanups have been “terribly slow” in realizing that potential reproductive damage to wildlife and people is important when setting cleanup goals. The EPA is much more focused on reducing human cancer risk from eating fish and on the outright mortality of animals.
“If the only consideration was to protect wildlife, that (harbor cleanup) would not be enough,” said John Giesy, a Michigan State University fisheries and wildlife professor. “But that was purely a societal decision, a risk management decision. EPA felt it was a decision they could live with.”
Goldman, one of the highest-ranking officials at the EPA, acknowledges that her agency should focus more on protecting the health of natural resources when regulating chemicals and cleaning up toxic waste. But she blames the failing on a need for better science to predict ecological impacts.
“The criticism is well-taken,” she said. “In the absence of better tools, we go with the things we do know, like cancer. What is new is this general recognition of the connection between risks to wildlife and the risk to human health.”
Goldman warned, however, that excavating old pollutants such as DDT and PCBs from the bottom of waterways sometimes can lead to more contamination of the fish. “It may be that the best possible thing is to leave them buried,” she said.
When it comes to tackling these hormone-disrupting pollutants, the nation’s most massive problem lies in Los Angeles’ own back yard.
From 1950 to 1970, DDT manufacturer Montrose Chemical Corp. of Torrance dumped several million pounds of the pesticide into county sewers that flow into the ocean off the Palos Verdes Peninsula. Due to a human cancer threat, warnings already have been posted on the peninsula and at Los Angeles Harbor advising against eating croaker and other fish caught close to shore.
Their eggs poisoned by DDT, populations of brown pelicans, eagles and other birds plunged in the 1970s. Although most now appear to be recovering, scientists say fish and wildlife still are suffering some lingering reproductive effects.
Specific scientific evidence of the damage, however, has been kept confidential by U.S. Justice Department attorneys, who are suing Montrose and other industries to seek compensation for wildlife and habitat losses. The federal government is soon expected to announce a proposal for restoring the coastal resources that is bound to be costly.
Today, no one wants to repeat the mistakes that left such enduring environmental dilemmas.
“Industry has suffered greatly from DDT and other things that have come back to haunt them,” said Glen Fox, a Canadian government biologist who has studied the impacts of Great Lakes pollution for two decades.
“They cannot afford to ignore a problem with a chemical that could affect your reproduction or your children’s reproduction. They are so scared spitless of that sort of thing. If there was ever an issue industry would probably act on, it’s this one.”
Anatomy of a Cleanup
Cleaning up Waukegan Harbor, on Lake Michigan 35 miles north of Chicago, illustrates the difficulty of handling sites contaminated with toxic chemicals. After years of dumping by Outboard Marine Corp., the harbor had the worst contamination from polychlorinated biphenyls, or PCBs, in the United States. The $21-million cleanup, a high priority in the Superfund program, began in 1988 and was completed in 1993. Here is a look at how the process was accomplished.
1. One million pounds of PCB-laced sediment and soil were dredged from Slip 3--the main source of PCBs in the harbor--as well as Crescent Ditch and North Ditch.
2. The materials were pumped into a holding pond and dried in West Containment Cell.
3. Almost 13,000 tons were cooked at high temperatures in a mobile processor at the West Containment Cell that separated the PCBs from the sediment and concentrated them the PCBs in an oil-based liquid. The liquid was hauled to an incinerator in Texas.
4. Slip 3 was turned into a huge containment cell to permanently hold untreated soils and sediments dredged from the harbor. The idea is to prevent lake water from flowing in.
SLIP 3 CONTAINMENT CELL
* A 290-foot cutoff wall was built at the mouth of the slip to cut it off from the rest of the harbor. The wall consists of two steel sheets 20 feet apart and anchored 7 feet deep into the clay layer.
* A large slurry wall, 3 feet thick, was connected to the cutoff wall to enclose the remainder of Slip 3.
* An underwater layer of hard, silty clay was added between the steel sheets.
* Steel braces were placed every 30 feet along the wall.
* A rock berm was constructed diagonally to the cutoff wall, extending 40 feet along the floor of the harbor.
5. Hydraulic dredging removed 32,000 cubic yards of contaminated sediments from the upper harbor floor. The material was pumped into an intake pipe and discharged into the containment cell at Slip 3.
6. Two smaller containment cells were built to permanently hold wastes from the North Ditch and the treated sediment from the mobile cooking process.
7. Water in the cells was continuously monitored by wells. A water-treatment plant was built to clean any polluted water extracted from the cells.
8. A new boat slip was constructed in the harbor to replace the old one.
9. Once the sediments settle, Slip 3 will be sealed.
Disruptive Potential
About 45 pesticides and industrial chemicals disrupt hormones in laboratory tests, which means they have the potential to cause reproductive disorders in wildlife or people. Here are some in volume produced annually in the United States.
CHEMICAL HERBICIDES
2,4-D Weed killer 40 million to 65 million pounds Alachlor Corn, peanuts, soybeans, 55 million sorghum to 70 million pounds Atrazine Corn 70 million to 80 million pounds INSECTICIDES Carbaryl Lawns, corn, soybeans 10 million to 15 million pounds DDT, DDE Banned in United States in 1973 because of severe impact on birds and fish INDUSTRIAL ELEMENTS Cadmium Batteries, metal plating 1,700 tons pigments, plastics Dioxins Industrial byproduct Lead Batteries, ammunition, paints 1.1 million tons Mercury Thermometers, batteries 160 million tons PCBs Banned in 1977. Were used as insulating material in electrical equipment and as hydraulic fluid
Sources: U.S. Environmental Protection Agency, Tufts University
