Pharmaceuticals in Waterways Raise Concerns ...
From the Washington Post - 23 June 2005
Effect on Wildlife, Humans Questioned
By Juliet Eilperin
Washington Post Staff Writer
Academics, state officials and environmental advocates are starting to question whether massive amounts of discarded pharmaceuticals, which are often flushed down the drain, pose a threat to the nation's aquatic life and possibly to people.
In waterways from the Potomac to the Brazos River in Texas, researchers have found fish laden with estrogen and antidepressants, and many show evidence of major neurological or physiological changes.
No one has seen evidence of effects on human health, but a number are asking publicly why the federal government is not taking a more aggressive approach to what they see as a looming problem.
In October 2002, Maine's Department of Environmental Protection asked federal scientists to analyze water samples to determine to what extent prescription drugs had seeped into the state's waterways. Worried that discarded birth-control pills, antidepressants and other drugs could affect the state's fishing industry and public health, the department's Ann Pistell hoped the federal Environmental Protection Agency's Northeast office could give her a speedy answer.
It was 2 1/2 years before she received a partial report identifying drugs in the water without a detailed explanation -- it came in the past week -- and she said she is still waiting for a full breakdown.
"We're sort of baffled and frustrated by the lack of a sample analysis," said Pistell, an environmental specialist. "We see this as an emerging issue. The more we find out, the more concerned we are."
Some state officials have started organizing. Raoul Clarke, an environmental administrator in Florida's Department of Environmental Protection, has worked with colleagues to establish a listserv where state and local officials can exchange information with concerned activists.
"There are many unanswered questions, but these things are showing up, and people are taking notice," Clarke said.
EPA officials say they are still gauging the seriousness of the threat. Technological advances in testing make it possible to detect very low levels of hormones and chemical compounds in waterways, they say, and it is unclear whether such levels harm animals and people.
Hal Zenick, who monitors health issues in the EPA's Office of Research and Development, said several agencies are working to determine whether such contaminants "lead to exposures, and do these exposures have implications for health effects."
Others, including drug manufacturers and sewage treatment operators, say that while they are monitoring the contaminants, their threat has been overstated.
Thomas White, an environmental consultant for the Pharmaceutical Research and Manufacturers of America (PhRMA), said industry studies indicate there are "no appreciable human health risks" and no "appreciable impacts on the aquatic environment" linked to drugs in the water.
In recent months, however, scientists have issued a series of findings suggesting that discarded drugs, which pass through municipal wastewater systems and into rivers, lakes and streams, could affect the environment. In 2002, a U.S. Geological Survey (USGS) study found these kinds of contaminants in 80 percent of the 139 streams it sampled in 30 states.
Other researchers suspect that hormones and medicines in the water may be responsible for effects on wildlife that include feminizing male fish and making others sluggish or uninterested in eating.
Rebecca D. Klaper, an ecological genomics scientist at the University of Wisconsin at Milwaukee, recently exposed fathead minnows to a popular anti-cholesterol drug at a level that was only slightly higher than what now occurs in area streams. She had to stop the week-long experiment after 24 hours because the fish were struggling to survive.
"They were sitting at the bottom of the tank, barely moving and barely breathing," Klaper said in an interview. "We're concerned [these pharmaceuticals] are not only having an effect on aquatic organisms, but on human populations as well."
Timothy S. Gross, a USGS toxicologist, has spent several years studying how fish are faring downstream from Las Vegas. He examined three species -- carp, largemouth bass and the endangered razorback sucker -- and detected "a very large and marked decrease in sperm quality and quantity" in all three populations.
There are enough carp and bass to withstand such effects, Gross said, but the razorback sucker may not recover. "When you have a species already on the brink, this may push them over the brink," he said.
Senate Minority Leader Harry M. Reid (D-Nev.), who has secured $2.5 million over the past decade to fund the Geological Survey's water quality studies in the Las Vegas Valley, said the government needs "to do a comprehensive national study to determine how these contaminants might affect our health, our water supplies and our environment. I think it would be irresponsible not to provide funding on this issue. It is a wise, and necessary, investment in our future."
But several rank-and-file EPA employees said senior agency officials have expressed little interest in the subject.
Hilary Snook, an EPA research scientist who has been analyzing pharmaceutical levels in about 45 water samples from Maine, Connecticut, New Hampshire and Vermont, said he has yet to receive funding from headquarters for the project. As a result, he said, his office lacks the money to complete the study quickly.
"I don't think there's much political will at all" to tackle the issue, Snook said. "We should at least look at it. We shouldn't be burying our heads in the sand."
State and local officials are growing increasingly impatient. David Galvin, who manages the hazardous waste program in King County, Wash., is coming under pressure from county residents to collect unused pharmaceuticals from hospitals as well as from elderly residents' homes. He is working with the nonprofit Product Stewardship Institute in Boston to start a national dialogue between drug manufacturers and government agencies on how to minimize the environmental impact of discarded medicines.
"Otherwise, we at the local level are going to be stuck with figuring out how to deal with it and having to pay for it," Galvin said. "I'd rather that not happen."
Maine officials hope to establish a program that would encourage consumers to mail back unused drugs to be incinerated, and they want drug manufacturers to pay for it. But in February, according to a letter obtained by the Natural Resources News Service, PhRMA wrote that it was "opposed to the recommendation that manufacturers solely fund this approach."
Pistell and others would like to start taking back medicines, but, she said, "the state is not in a position to pay for it."
See - Pharmaceuticals in Waterways Raise Concerns.
posted by Concerned Ratepayer at 2:41 PM
1 Comments:
An interesting read as well:
Common industrial chemicals in tiny doses raise health issue ...
Advanced Tests Often Detect Subtle Biological Effects; Are Standards Too Lax?
Getting in Way of Hormones
By PETER WALDMAN Staff Reporter
THE WALL STREET JOURNAL
For years, scientists have struggled to explain rising rates of some cancers and childhood brain disorders. Something about modern living has driven a steady rise of certain maladies, from breast and prostate cancer to autism and learning disabilities.
One suspect now is drawing intense scrutiny: the prevalence in the environment of certain industrial chemicals at extremely low levels. A growing body of animal research suggests to some scientists that even minute traces of some chemicals, always assumed to be biologically insignificant, can affect such processes as gene activation and the brain development of newborns.
An especially striking finding: It appears that some substances may have effects at the very lowest exposures that are absent at higher levels.
Some scientists, many of them in industry, dismiss such concerns. But the new science of low-dose exposure is challenging centuries of accepted wisdom about toxic substances and rattling the foundation of environmental law.
Modern pollution restrictions aim to limit exposures to levels past studies have found safe. For example, it's known mercury can cause learning problems in children if it's above 58 parts per billion in the bloodstream. Dividing 58 by 10 to provide a margin of safety, U.S. regulators advise that children and young women not accumulate more than 5.8 parts per billion of mercury, by limiting consumption of certain fish such as tuna.
But what if it turned out some common substances have essentially no safe exposure levels at all? That was ultimately what the U.S. Environmental Protection Agency concluded about lead after studying its effects on children for decades. Indications some other chemicals may have no safe limits have led regulators in Europe and Japan to bar the use of certain compounds in toys and in objects used to serve food. In the U.S., federal scientists are devising new tests that could be used to screen thousands of common chemicals to make sure they're safe at extremely low exposures.
Using advanced lab techniques, scientists have found that with some chemicals, traces as minute as mere parts per trillion have biological effects. That's one-millionth of the smallest traces even measurable three decades ago, when many of today's environmental laws were written. With some of these chemicals, such trace levels exist in the blood and urine of the general population.
Some chemical traces appear to have greater effects in combination than singly, another challenge to traditional toxicology, which tests things individually.
The human body is complex, and effects seen in tests on small laboratory animals and in human cells don't necessarily mean health risks to people. "The question is what do we do about these low levels once we know they're there," says Steve Hentges of the American Plastics Council, a trade association.
For their part, companies and industry groups have attacked low-dose research as alarmist and are challenging the findings with scientific studies of their own. Some industry studies have contradicted the low-dose findings of university and government labs. One reason, says Rochelle Tyl, a toxicologist who does rodent studies on contract for industry groups, is that academics seek "to find out if a chemical has an intrinsic capacity to do harm," while industry scientists try to measure actual dangers to people.
The result is that low-dose research has sparked a number of heated scientific and regulatory controversies:
· Tiny doses of bisphenol A, which is used in polycarbonate plastic baby bottles and in resins that line food cans, have been found to alter brain structure, neurochemistry, behavior, reproduction and immune response in animals. Makers and users of the chemical maintain, citing a Harvard review of 19 studies, that the chemical is harmless to humans at such levels.
· Minute levels of phthalates, which are used in toys, building materials, drug capsules, cosmetics and perfumes, have been statistically linked to sperm damage in men and genital changes, asthma and allergies in children. The U.S. Centers for Disease Control and Prevention has detected comparable levels in Americans' urine. Manufacturers say there is no reliable evidence that phthalates cause any health problems.
· A chemical used in munitions, called perchlorate, is known to inhibit production of thyroid hormone, which children need for brain development. The chemical has been detected in drinking-water supplies in 35 states, as well as in fruits, vegetables and breast milk. The EPA has spent years mulling what is a safe level in drinking water. The Defense Department and weapons makers maintain it is harmless at much higher doses than those that Americans ingest.
· The weed killer atrazine has been linked to sexual malformations in frogs that were exposed to water containing just 1/30th as much atrazine as the EPA regards as safe in human drinking water. The herbicide's main manufacturer, Syngenta AG, says other studies prove atrazine is safe. The EPA favors more study.
With so much still unknown, regulators are proceeding on different tracks in different countries. Japan's government designates about 70 chemicals as potential "endocrine disruptors" -- substances that may, at tiny doses, interfere with hormonal signals that regulate human organ development, metabolism and other functions. Japan has just completed a $135 million research push on endocrine disruptors, including setting up a national research center. The Japanese government also has banned certain phthalates in food handlers' gloves and containers, after detecting them in food. One manufacturer, Fujitsu Ltd., has pledged to phase out its use of most suspected endocrine disruptors over coming years.
The European Union has banned some kinds of phthalates in cosmetics and toys, and it is considering a ban on nearly all phthalates in household goods and medical devices. The EU also is planning to require new safety tests for thousands of industrial chemicals, many of which already exist in people's bodies at trace levels. Industry, which would have to bear the cost of proving countless current products safe, is fighting the measures, calling them a massive unnecessary burden.
In the U.S., there are divisions within the government. The White House plays down the issue, saying the low-dose hypothesis is unproved. But many federal scientists and regulators at the EPA and Health and Human Services Department are forging ahead with new methods for assessing possible low-dose dangers. Legislatures in two states, California and New York, are considering bills that would ban use of certain phthalates in toys, child-care products and cosmetics, while a California bill would restrict bisphenol A.
Earliest Concerns
One of the early scientists to focus on possible low-dose risks was biologist Theo Colborn of the World Wildlife Fund. Studying the decline of certain birds, mammals and fish in the upper Midwest, Dr. Colborn spotted some patterns: Species that struggled to survive in the industrialized Great Lakes thrived in inland areas that were less polluted. And some offspring in more-polluted regions had gender abnormalities, such as feminized sex organs in males. She theorized that trace amounts of chemicals in the environment were disrupting hormones.
Dr. Colborn and colleagues popularized low-dose concerns in a series of conferences, articles and a best-selling 1996 book called "Our Stolen Future." That year the EPA asked an outside advisory panel to consider ways of screening industrial chemicals for hormonal effects, a process still incomplete.
In 2000, a separate EPA-organized panel, after reviewing 49 studies, said some hormonally active chemicals affect animals at doses as low as the "background levels" to which the general human population is subject. The panel said the health implications weren't clear but urged the EPA to revisit its regulatory procedures to make sure such chemicals are tested in animals at appropriately small doses.
The EPA hesitated. It responded in 2002 that "until there is an improved scientific understanding of the low-dose hypothesis, EPA believes that it would be premature to require routine testing of substances for low-dose effects."
The Bush administration's regulatory czar, John Graham -- administrator of the Office of Information and Regulatory Affairs at the White House Office of Management and Budget -- later publicly dismissed as unproven the idea that the hormonal system could be disrupted by multiple low-dose exposures to industrial chemicals. For the past two years, the administration has proposed funding cuts for EPA research on suspected endocrine disrupters, but Congress has kept the funding roughly level at about $10 million a year.
Since the review panel met in 2000, scientists have published more than 100 peer-reviewed articles reporting further low-dose effects in living animals and in human cells. These findings are generating some early insights in the thorny process of translating laboratory data into conclusions about human health.
Less Is More
One of the most provocative is that some hormonally active chemicals seem to have more effects at extremely low exposures than at higher ones. This challenges an axiom of toxicology stated by the Swiss chemist Paracelsus nearly 500 years ago: The dose makes the poison.
Toxicologists traditionally derive risk by exposing rodents to chemicals to find the lowest dose that leads to tumors, birth defects or other readily observable effects. Regulators then divide the highest "no-observable-effect" dose by an "uncertainty factor" -- anywhere from 10 to 1,000 -- to set a maximum human exposure they can be confident is safe.
But now researchers have found chemicals that have hormonal effects on lab animals and on human cells in much tinier amounts than their standard no-observable-effect levels. And with some of these chemicals, as the tiny doses given to animals are increased, the effects recede. Then, at much higher levels, broad systemic impacts appear, such as reduced body weight.
An example is bisphenol A, or BPA, the ingredient in polycarbonate baby bottles and food-can linings. It evidently is widespread in the environment. In the U.S., the CDC has found traces of it in 95% of urine samples tested. In Japan, researchers have detected BPA in fetal amniotic fluid and the umbilical cords of newborns.
Studying BPA in rats in 1988, the EPA concluded the lowest exposure with an "observed adverse effect" was 50 milligrams a day per kilogram of body weight (one kilogram = 2.2 pounds). Dividing 50 by an uncertainty factor of 1,000, the agency set a daily safe limit for humans of 0.05 milligrams of BPA per kilogram of body weight. Since then, however, academic scientists in several countries have done more than 90 studies that have found BPA effects on animals and human cell cultures from exposures well below this level.
The EPA used a relatively crude measure of the chemical's effects: changes in rodents' body weights. The new studies looked at subtler, hormone-related effects. Some studies found changes in rodents' reproductive organs and brains at doses as low as 0.002 milligram per kilogram of body weight per day. That is just one-25,000th the dose that the EPA said was the lowest exposure having an observable adverse effect.
Disrupting Hormones
Seeking to explain this pattern, scientists cite the endocrine system's exquisite sensitivity. Animals and humans secrete infinitesimal amounts of various hormones, such as estrogen, that trigger responses when they occupy special receptors on the cells of various organs. BPA is among numerous chemicals that can mimic estrogen by occupying cells' estrogen receptors. When they do this at critical phases of development, the chemicals can trigger unnatural biological responses, such as brain and reproductive abnormalities.
At higher doses, however, BPA and other endocrine disruptors -- instead of triggering the unnatural responses -- appear to overwhelm the receptors. That explains, scientists say, why some chemicals seem to have more potent hormonal effects at very low doses than at higher ones.
Mr. Hentges of the American Plastics Council says studies show BPA is harmless at the tiny levels to which humans are exposed. In 2001 the plastics council agreed to pay Harvard's Center for Risk Analysis, part of the Harvard School of Public Health, $600,000 to review BPA studies. The 10 panelists found "no consistent affirmative evidence of low-dose BPA effects" on the basis of 19 studies that were selected by April 2002 for review.
However, many more BPA studies kept coming out, and when the center published its report last fall, three of the 10 panelists declined to be listed as authors. "There are other papers published after the 'cut-off' date that the panel did not review that may have altered their conclusions," says one of the three, Paul Foster of the National Institute of Environmental Health Sciences. A fourth, Claude Hughes of Quintiles Transnational Corp., a pharmaceutical consulting firm, signed but made the same point in a journal commentary criticizing the report and calling for a new EPA risk assessment. The Harvard risk center's executive director, George Gray, acknowledges that a "torrent of new papers on BPA" may have made it impossible for the panel to review everything by its deadline.
The plastics council's Mr. Hentges says his group reviews all studies on BPA and believes none have changed the basic conclusion of the Harvard report. "We continue to believe that the weight of evidence indicates BPA poses no risk to human health," he says.
Chemicals in Combination
Environmental chemicals don't exist in isolation. People are exposed to many different ones in trace amounts. So scientists at the University of London checked a mixture. They tested the hormonal strength of a blend of 11 common chemicals that can mimic estrogen.
Alone, each was very weak. But when scientists mixed low doses of all 11 in a solution with natural estrogen -- thus simulating the chemical cocktail that's inside the human body today -- they found the hormonal strength of natural estrogen was doubled. Such an effect inside the body could disrupt hormonal action.
"In isolation, the contribution of individual [estrogen-like chemicals] at the concentrations found in wildlife and human tissues will always be small," wrote the scientists, led by Andreas Kortenkamp, who directs research on endocrine disruptors for the EU. But because such compounds are so widespread in the environment, the researchers concluded, the cumulative effect on the human endocrine system is "likely to be very large."
To test chemicals, toxicologists traditionally dose animals with a single substance and then dissect them. But this method can't spot the subtle effects associated with today's multiple exposures to low-dose chemicals, says John Bucher, of the National Institute of Environmental Health Sciences.
Now he and his boss, Christopher Portier, are revamping the federal government's National Toxicology Program, which sets standards for how chemicals are tested. Over about seven years, they hope to develop a series of lab tests that will ultimately screen some 100,000 industrial compounds, individually and in mixtures, for biochemical "markers" such as effects on specific genes.
The chemicals then will be ranked by mechanism of action and suspected toxicity, and assigned priorities for further study. "It's taken us 25 years and $2 billion to study 900 chemicals," Dr. Portier says. "If this works, we can study 15,000 in a year."
11:17 AM, January 13, 2006
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