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    Persistent Organic Pollutants

  Corps find PCBs near Bonneville Dam island
New study linking vinyl chloride to dioxin
EPA Urged to Perform Emergency PCB Clean-up - Fox River Green Bay, WI
People of Color Battle Toxics in Communities Across the U.S.
Subject: The American People's Dioxin Report
PCB Health Effects on the Uterus



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This relates to an illegal dump which the Army Corps of Engineers was aware of, but took no action on, for several years, on the Columbia River. The article is from the Portland Oregonian. The Yakama Nation, Umatilla and other Native peoples in the region fish the Colombia River. The Cascade and Klickatat bands of Yakama are the "River People" that still reside along the Colombia River and practice subsistence fishing. - IEN

 

Corps find PCBs near Bonneville Dam island

Three samples taken from sediment off an old Bradford Island landfill show high levels of the cancer-causing chemical



February 1, 2001
By Don Colburn of The Oregonian staff


The U.S. Army Corps of Engineers has found unacceptably high levels of toxic PCBs in sediment samples taken from the Columbia River near Bonneville Dam.

The apparent source of the PCBs is junked electrical equipment dumped over the edges of a small landfill on the eastern end of Bradford Island, just upstream from the dam, officials said. The submerged waste dates as far back as 40 years.

Three of four samples collected by divers in December contained levels of PCBs above the benchmark level set by federal and regional environmental agencies for dredged material. Results above that benchmark are considered potentially dangerous to human and environmental health.

PCBs, or polychlorinated biphenyls, are cancer-causing chemicals that were widely used to insulate electrical equipment and protect against fire. They were banned from use in 1976. PCBs are especially worrisome because of their durability and tendency to work their way up the food chain into plants and animals.

Investigation and cleanup of the Bradford Island site is proceeding under a 1998 voluntary agreement between the corps and the Oregon Department of Environmental Quality.

The latest finding, showing that PCBs leaked from the equipment and settled into the river bed, complicates that effort.

"We've got a local, small area impacted by the PCBs," said Matt McClincy, DEQ's project manager for the Bradford Island cleanup. "How significant that is will take us more testing to figure out. Now we know we have more work to do."

He said authorities may have to conduct tissue samples in freshwater clams, crayfish and fish from the river to determine the extent of possible harm from the PCB pollution.

The December cleanup was curtailed by stormy weather. Divers are scheduled to collect two more sets of sediment samples this month and to remove all the submerged electrical equipment by the end of February, corps and DEQ officials said.

"We need to complete the retrieval in February," said corps spokeswoman Dawn Edwards.

The benchmark for PCBs in dredged material -- the threshold for worry -- is .13 parts per million (ppm). Three of

the sediment samples exceeded that by measuring 8.3 ppm, 5 ppm and .15 ppm. A fourth sample, taken five feet from an electrical capacitor, was clean.

Tests to detect hydrocarbons, a sign of petroleum leakage, showed no contamination.

The Bradford Island landfill, covering less than an acre, was in use from 1942 to 1982. It contains household garbage and industrial waste, according to the corps. That portion of the island is closed to the public.

A survey by divers last fall located additional electrical equipment, including capacitors, lightning arresters, ballasts, relays and miscellaneous pieces of metal and porcelain among the debris along the riverbank near the edge of the landfill. PCBs were found last November in four of six pieces of electrical equipment retrieved by divers.

The corps notified federal and state environmental authorities in 1996 of the existence of a closed landfill on Bradford Island. Corps officials said they had discovered the landfill, for which no permits were issued, during a routine environmental audit.

In January, citing documents obtained under the Freedom of Information Act, The Oregonian reported that the corps had been notified of the landfill's existence by two employees in 1992 -- but had not reported it to environment regulators until four years later.



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New study linking PVC plastics with dioxin when burning. This has important implications for hospital waste management and procurement.



Gary Cohen
GEN SCI:Dioxin:
Test shows vinyl chloride biggest dioxin producer
SAPPORO, June 21 Kyodo

An experiment has found that of three types of plastic, vinyl chloride produces the largest amount of dioxin when burned and nonplastic substances produce more dioxin when burned together with chlorine compounds, according to researchers.

The experiment was conducted by a research group formed jointly by the Gifu Prefectural Institute of Health and Environmental Sciences and the National Institute for Environmental Studies. The results were announced Tuesday to an environmental science conference in Sapporo.

Scientists already know that dioxins, which are cancer-causing chemicals, are produced through burning, particularly of plastics but it is unclear how much dioxin is produced by each substance.

The experiment's results could prove useful in efforts to reduce the amount of dioxins being released into the environment.

The researchers used small incinerators to burn three types of plastic under various conditions. In addition to vinyl chloride, the other substances were polystyrene, used in foam packaging, and polyethylene, which is found in a wide variety of household products.

The experiment measured the amount of the most poisonous dioxin found in a cubic meter of gas emitted from the burning. Measurements were in nanograms, each being one-billionth of a gram.

Vinyl chloride produced 16 nanograms of dioxin per cubic meter, the highest amount of the three plastics. For polystyrene, the amount was 0.28 nanograms, and for polyethylene, 1.2 nanograms.

The numbers increased when the plastics were incinerated together. When vinyl chloride and polyethylene were mixed, the amount rose to 19 nanograms.

The same tendency was observed when nonplastic substances were added.

Newspaper soaked in table salt and newspaper burned with vinyl each produced more than 30 nanograms of dioxins. Newspaper alone, by comparison, produced a mere 0.17 nanogram.

The researchers concluded that even such seemingly innocuous substances such as newspaper can increase the amount of dioxin production when burned together with compounds containing chlorine.

The finding also highlights the importance of separating garbage before it is incinerated, they said.

In recent years, manufacturers have cut back on their use of vinyl chloride, used for containers, wrapping materials and other products, following reports that it produces large amounts of dioxin when burned.



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Note that the Fox River is within the Native lands of the Oneida, Menominee, Stockbridge-Munsee and Ojibwe tribes. Numerous pulp and paper mill plants and paper de-inking processing throughout the years have lead to this devastingt contamination. The Indigenous Environmental Network (IEN) and the Great Lakes Regional IEN recently sponsored a Natives Peoples Dioxin Hearing at Greenbay, Wisconsin. The issue at Fox River was brought up. Stay tune for the report from this hearing. - Indigenous Environmental Network -



March 7, 2000

EPA Urged to Perform Emergency PCB Clean-up




Green Bay, WI --- The equivalent of a major toxic PCB spill has occurred in the Fox River as the result of an incomplete dredging demonstration near the Fort James Corporation in Green Bay.

Citizens urge the U.S. Environmental Protection Agency to step in immediately to clean up the problem to protect public health and wildlife.

Last fall's dredging demonstration at the worst Fox River PCB hotspot, known as "56/57," removed only a fourth of the 120,000 cubic yards of contaminated sediments identified in the hotspot. Sampling results were finally publicized this past week showing the dredging cut into buried layers with more than 280 ppm PCBs and left them exposed to the river currents. 50 ppm PCBs are considered hazardous waste under state and federal laws.

"This hotspot exposure is the equivalent of open barrels of hazardous waste on the river bottom. At any other time, this would be considered an emergency situation, but our government agencies have yet to take action," stated Rebecca Katers, of the Clean Water Action Council.

Clean Water Action Council has publicly opposed this project due to the deliberate poor design and lack of funding for proper remediation. In addition, the state signed a contract last fall with Fort James Corporation relieving the company of further liability if they performed only a partial cleanup.

"We're calling on Frank Lyons, the Regional Administrator for EPA in Region V, to take action. The federal government may now be the only agency able to quickly enforce an emergency cleanup at this hotspot," added Katers. "The state has ignored our concerns, signed contracts limiting their enforcement ability, and allowed money rather than sound science to drive their decisions."

"This project is a fraud. Polluters should not be allowed to use this badly designed project as a precedent for the rest of the Fox river cleanup, or as a nation-wide example of the failure of dredging," stated Katers.

BACKGROUND ON THE 56/57 PROJECT:

This "demonstration" has been flawed since it's inception in January 1997, when Governor Thompson arranged a surprise $10 million contract settlement between the state and the Fox River Group (seven paper Industries responsible for the PCB contamination). The news media, public, federal agencies, and tribes were not informed or consulted until the contract was already signed.

$7 million of the settlement was earmarked for one Fox River dredging demonstration, and the 56/57 hotspot was chosen as the site. The contract specified DNR would hire consultants and contractors nominated by the Fox River Group for the work.

When it became clear last year that $7 million was not enough, the DNR negotiated another surprise, secret contract which relieved Fort James Corporation of liability in exchange for an additional $2 million in cleanup funding. Under the contract, Fort James was only responsible for removing 80,000 cubic yards of the 120,000 cubic yards at the site.

But because the project was started too late in the year and several suspicious technical problems arose, only 30,000 cubic yards were removed. (... note that most of the technical problems at 56/57 did not occur at the DNR/EPA controlled demonstration project near Little Chute and Kimberly.)

For two years, Clean Water Action Council has warned this project would be a disaster, and felt it was deliberately promoted by the paper industry to portray dredging as a dangerous cleanup option for the Fox River, to build support for their "natural recovery" do-nothing option. Recent publicity from the paper industry reinforces this belief, as they now claim the 56/57 project proves their concerns, they lay the blame on the Wisconsin Department of Natural Resources, and they deny responsibility for the choice of contractors at the site.

Many government agencies have already shown elsewhere that sediment dredging can be conducted safely and effectively, when proper procedures are used. Clean Water Action Council supports the dredging, removal, and detoxification treatment of PCB hotspot sediments.

This project has been used to mislead the public, and to pretend that progress is being made. Yet, it was never a true "demonstration," as DNR staff have admitted many times. No new technologies were used, though citizens had hoped innovative new PCB destruction technologies (such as gas-phase reduction, thermal desorption, etc.) would be used to destroy the PCBs rather than simply landfill them. DNR staff have told Clean Water Action Council members they consider the project the beginning of the actual cleanup and they simply wanted to get started.

If this is the case, the project sets a bad example, and illustrates the failure of the state's emphasis on a "cooperative approach" with polluters.


Rebecca Leighton Katers
Clean Water Action Council of N.E. Wisconsin
East Port Center, 1270 Main Street, Suite 120 Green Bay, WI 54302
Phone: 920-437-7304, Fax: 920-437-7326
E-mail: CleanWater@cwac.net Homepage: www.cwac.net

 



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EJ article in today's Lycos Environmental New Service-Forwarded

People of Color Battle Toxics in Communities Across the U.S.



By Cat Lazaroff

WASHINGTON, DC, February 11, 2000 (ENS) - Ten African American children are visiting Washington, D.C. this week, but they did not come to see the usual tourist attractions. They are here to illustrate the dangerous legacy of hazardous wastes, contaminated manufacturing sites, and polluting industries, placed predominantly in poor, non-White communities.

The concentration of chemical plants near this home in Mossville, Louisiana, have earned the region the name "Cancer Alley." Mossville is a poor, African American community.

The children, from Memphis, Tennessee and Pine Bluff, Arkansas, are here to draw attention to the sixth anniversary of President Bill Clinton's executive order on environmental justice. The order, "Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations," was intended to focus federal attention on the environmental and human health conditions in minority communities and low-income communities.

These children, environmental justice activists say, starkly demonstrate how that order has failed.

"They have major tumors, respiratory diseases, endometriosis from toxins, nervous disorders," says Dr. Mildred McClain, executive director of the People of Color and Disenfranchised Communities Environmental Health Network (PCDCEHN. "The young man from Arkansas went into a coma."

These illnesses were due to exposure to toxic chemicals in the children's homes, schools and playgrounds, McClain says. In the early 1990s, Memphis became infamous as the city with the most uncontrolled hazardous waste sites in the nation. Rates of cancer, chronic respiratory illness, as well as neurological disorders are significantly higher among non-White Memphis residents than among Whites.

This checkpoint guards the entrance to the U.S. Army's Pine Bluff Arsenal, which holds 12 percent of the nation's chemical weapons stockpile - just outside the predominantly African American community of Pine Bluff. Pine Bluff is the site of the Pine Bluff Arsenal, a Cold War era chemical weapons production and storage facility that now holds about 12 percent of the nation's chemical weapons stockpile. A proposed $200 million incinerator under construction in Pine Bluff would be the nation's second chemical weapons incinerator.

Pine Bluff is 53 percent African American, a proportion 341 percent higher than the national average. The town is also very poor, with 28 percent of its residents living below the poverty level, according to the 1990 Census. It is a classic example of the communities that environmental justice advocates say are burdened by the bulk of the nation's polluters.

On Thursday, the children visited Howard University Hospital, one of the nation's first teaching hospitals serving African American doctors. Their meeting with physicians and scientists, organized by Dr. Rueben Warren, associate administrator for Urban Affairs at the Agency for Toxic Substances and Disease Registry, was as much to increase knowledge of environmental illnesses as it was to help the children themselves.

Today, the children were at a press conference hosted by People of Color and Disenfranchised Communities Environmental Health Network (PCDCEHN) and the Interim National Black Environmental and Economic Justice Coordinating Committee (INBEEJCC). These mouthfuls of acronyms spell out a sea change in how people of color are tackling the pollution in their own backyards.

Pine Bluff Arsenal employees wearing Level A protective equipment to monitor the chemical weapons in a storage igloo. A new force for environmental protection is emerging in the United States, gaining strength from a broad network of church groups and citizens groups from the nation's poorest regions. The nation's environmental justice movement has set itself the ambitious agenda of ending decades of environmental racism stemming from the concentration of toxic industries and hazardous wastes located in communities of color.

"We are trying to really get national attention to the critical crisis of health in communities contaminated by toxic pollution," says Ka Flewellen of the Preamble Center. The Center, an independent research and public educations organization based in Washington, DC, is one of dozens of groups cooperating to form the INBEEJCC.

The fledgling coalition was created to harness the combined power of local groups that have been battling pollution and toxic wastes in their communities. In exchange, the coalition offers a unified, national voice against the disproportionate placement of polluting industries in communities of color.

"It's the first time that an effort like this is being launched under the leadership of people of color," said McClain.

Damu Smith of Greenpeace is the interim coordinator for the INBEEJCC, and was instrumental in organizing the coalition's first meeting last December. "I was looking at what was happening nationally," Smith says. "When I looked at what was happening around the country, it became clearer that the forces behind the movement to undermine environmental justice are very organized, very powerful, and are part of a nationally organized strategy to take away protections for people of color."

After a week long tour of polluting industries in Louisiana's "Cancer Alley," Greenpeace activists placed a 100 foot long banner in a dioxin-polluted bayou near the chemical giant PPG Industries.

To battle the "sinister forces in the nation, out to totally dismantle the environmental justice framework that we have worked so hard to achieve," people of color must unite in opposition of environmental racism, Smith said.

At a Washington, DC press conference in January, Smith, McClain and other environmental justice advocates issued a Declaration of a National State of Emergency on Environmental Racism and Economic Injustice.

"We come this day, in this place, in the seat of this nation's government to declare that toxic terrorism is being waged against the descendants of African people," McClain said.

The 14 page Declaration cites numerous reports supporting the activists' claim that Black communities and other communities of color are disproportionately overburdened with nearby hazardous waste sites, incinerators, petrochemical plants, lead contamination, dirty air and contaminated drinking water.

Among the evidence cited: A 1983 Congressionally authorized General Accounting Office study revealed that three out of four off site, commercial hazardous waste landfills in the southeast U.S. are located within predominately African American communities, even though African Americans make up just one fifth of the region's population.

A 1987 study, "Toxic Waste and Race," by the United Church of Christ Commission for Racial Justice - the first national study to correlate waste facilities and demographic characteristics - which found that race was the most significant factor in determining where waste facilities are located.

Among other findings, the study revealed that three out of five African Americans and Hispanic Americans live in communities with uncontrolled toxic waste sites, and that 15 million African Americans live in communities with at least one site.

A 1992 study by the National Law Journal, "Unequal Protection," uncovered significant disparities in the way the U.S. Environmental Protection Agency (EPA) enforces its laws: " There is a racial divide in the way the U.S. government cleans up toxic waste sites and punishes polluters. White communities see faster action, better results and stiffer penalties that communities where Blacks, Hispanics and other minorities live. This unequal protection often occurs whether the community is wealthy or poor."

In 1999, the Institute of Medicine released "Toward Environmental Justice: Research, Education and Health Policy Needs." The report concluded that government, public health officials, and the medical and scientific communities need to place a higher value on the problems and concerns of non-White communities.

Evidence from sources like these, indicating that people of color are still exposed to higher levels of pollution that Whites, and experience certain diseases in greater number than more affluent white communities, prompted African American leaders to question the effectiveness of Clinton's Environmental Justice order.

Peabody Coal Company's Kayenta mine covers over 10 miles on the Navajo Indian reservation in northeast Arizona.

"We're calling for some assessment by Clinton administration, which wants to appeal to voters with environmental concerns," said Flewellen. "What has been the record? What has actually been done?"

The INBEEJCC seeks a status report on the Executive Order, and wants particular attention to be paid to toxic pollution from federal facilities like the Pine Bluff Arsenal. To that end, the newly formed environmental justice coalitions met this week with White House officials, the Congressional delegations from Georgia and Tennessee. Recent meetings with EPA and Department of Energy (DOE) officials representatives have helped the groups lobby for federal action.

In December, the National People of Color and Disenfranchised Communities Environmental Health Network met with the EPA and the DOE for the first time to present a united message. "It was the first time we were able to get an audience with senior level officials from DOE and EPA," said McClain. "People of color have no significant input on decisions that are being made regarding national security and nonproliferation," she continued. "These decisions, we will be living with the consequences for a very long time."

The DOE and Department of Defense signed a Federal Facilities Environmental Restoration Dialogue Committee Final Report in April, 1996, which was to serve as a guidance for the involvement of communities in federal facility cleanup.

"Neither agency has adhered to it," said McClain.

These Water Treatment Units at the Savannah River Site can remove some radioactive contaminants, but not all Savannah.

"There's somebody living next to these places other than business people," McClain said, noting that her own home in Savannah, Georgia lies downstream of the DOE's Savannah River Site, where millions of gallons of highly radioactive wastes are stored. "There's regular folk, and they have not had a voice."

Throughout the year 2000, the environmental justice movement plans to mobilize action from non-White communities, and from the poorest White communities, which also often lack a voice in the siting of toxic facilities. Activities organized around Earth Day 2000 will help bring national attention to environmental justice issues. The groups also hope to encourage high voter turnout from people of color, and high participation in the 2000 Census.

Next year, they plan significant participation in the United Nation's World Conference against Racism, Racial Discrimination, Xenophobia and Related Intolerance in South Africa, to help raise the visibility of environmental racism worldwide.

"White people have the insulation of resources," said McClain. "We come home and get beat up." Pollution from federal facilities is an "issue we have not taken on head on before. Well, the hell with being poor. They're going to be trucking this stuff through our communities, we don't know anything about it. It's time to take a stand."



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Subject: The American People's Dioxin Report



November 4, 1999

Dear Dioxin Activist,

We are thrilled to announce that we have just released America's Choice: Children's Health or Corporate Profit, the American People's Dioxin Report. Many community leaders and scientists, as well as the staff of CHEJ, have spent untold hours since last January helping prepare this report. Now the grassroots network not only has a comprehensive study of the sources and heath effects of dioxin, but an important tool to use to establish strong protective policies to eliminate dioxin from our communities.

America's Choice: Children's Health or Corporate Profit consists of two documents. The first portion is the report itself, which summarizes the newest scientific research findings on the health effects of dioxin. The report also includes policy recommendations for twelve sources of dioxin. These recommendations provide clear workable solutions to eliminating dioxin sources without hurting our economy. The second portion is the Technical Support Document (TSD), which provides a comprehensive report on the health effects of dioxin. Copies of the report are available by contacting CHEJ and are also available on our web site (www.essential.org/cchw). The Technical Support Document will be made available exclusively on our web site as it is quite long and detailed.

The American People's Dioxin Report is intended to accomplish three goals:

Provide up-to-date scientific information and research on the effects of dioxin on human health.

Provide the American people with suggested protective policies which they can ask their elected officials to enact to prevent this life-threatening chemical from harming our families.

Engage the American people in a national debate, community by community, on the nature of government in our society -- how people become powerless as the corporations become powerful -- and why our government protects the right to pollute more than it protects the American people's health.

The science has been written and peer reviewed by leading dioxin experts including Dr. Beverly Paigen of Jackson Laboratories and Dr. Arnold Schecter at the University of Texas School of Public Health (writers), and Dr. Linda Birnbaum, US EPA and Dr. George Lucier, National Institute for Environmental Health Sciences (reviewers). The policy recommendations were written by more than 50 community leaders from across the country who participated in person and via phone, fax and e-mail, in twelve workgroups. Since there are so many sources of dioxin, we were unable to develop recommendations for all of them. The policy recommendations we came up with are a starting point for developing policies for your community. Our aim was to make the recommendations brief, yet comprehensive.

So what next, you ask. The answer is state-wide mobilization. It is time to take this report to our elected officials. Over the next six to eight months, public meetings and other gatherings will take place in cities across the country. These meetings will begin the public discussions about how to safeguard the health of the American people and launch efforts to establish protective policies to stop dioxin exposure. Elected officials need to enact -- and enforce -- health protections that will get tough on dioxin-spewing industries and prevent this life threatening chemical from harming our families. An event calendar is included in this email. If you'd like to get involved in one of the listed events, or organize an event in your state, please contact our office.

This is an exciting time for all of us working to stop dioxin exposure in our communities. Thank you for your continued efforts. We look forward to working with you over the coming year.

                For a dioxin-free future,

                Monica Rohde
                Dioxin Campaign Coordinator






STUDY SHOWS DIOXIN EXPOSURE RELATED TO ADVERSE CHILDHOOD BEHAVIOR AND LEARNING CAPABILITIES


Contact: Paul Cates
Pro-Media Public Relations
212-245-0510

(Washington, D.C.) - Scientific findings released today in a report by the Center for Health, Environment and Justice (CHEJ) revealed that nearly all Americans are exposed to unhealthy levels of dioxin through normal daily consumption of food. According to the report, America's Choice: Children's Health or Corporate Profit, children exposed to dioxins in utero during critical periods of development appear to be the most sensitive and vulnerable to the toxic effects.

Dioxin exposure has been associated with IQ defects, increased prevalence of withdrawn/depressed behavior, adverse effects on attentional processes, an increase in hyperactive behavior in children, disrupted sexual development, birth defects and damage to the immune system.

"Dioxin is a terribly lethal substance that can be eliminated from our environment by making simple changes in manufacturing and waste disposal processes," said CHEJ's Executive Director Lois Gibbs. Gibbs uncovered the toxic poisoning, including dioxin, of families at Love Canal twenty years ago, and has since become a leader in safeguarding the health of America's families.

"President Clinton recently called dioxin one of the most dangerous chemicals known when he announced that industry will now be required to report their releases of dioxin," Gibbs continued, "It's time for government to go beyond talking towards elimination."

Dangerous levels of dioxin are found in such common "healthy" foods as milk, cheese and beef, giving almost all of us a higher concentration of dioxin in our bodies than would be considered safe.

The report, compiled by CHEJ, reflects a decade's worth of research by leading scientists and respected community leaders. The report was peer reviewed by some of the nation's most respected scientists and health policy experts.

In addition to the medical findings, the report provides recommendations for ridding our environment of dioxins. Affordable, safe alternatives now in use can, if adopted more widely, replace the chlorine in paper mills and the incineration of medical waste that currently spew toxic levels of dioxin into our food supply.

 

 

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SBRP "Research Brief" - Number 62

Understanding the Effects of Polychlorinated Biphenyls on the Uterus


Regulation of uterine contractility is vital to successful reproduction. During a full-term pregnancy, the uterus remains relatively inactive from conception until the initiation of labor -- a period of about 280 days for humans. As the time of delivery approaches, the uterus becomes highly active with muscular contractions that increase in frequency and intensity until the fetus is forced out of the womb.

Fine-tuned control of uterine contractions is imperative not only for an effective labor at the end of pregnancy, but also for preventing premature labor. However, for reasons that are poorly understood, the regulation of uterine contractions appears to be susceptible to interference by certain environmental contaminants.

Some studies suggest that polychlorinated biphenyls (PCBs), a group of widespread, persistent environmental contaminants, may disrupt the natural termination of pregnancy by stimulating premature uterine contractions. Both PCB mixtures and individual congeners can stimulate contractions in isolated segments of uterus. Yet the cellular and molecular events underlying this form of reproductive toxicity are relatively unknown.

Researchers at the University of Michigan -- a partner in the Michigan State University Superfund Basic Research Program -- recently elucidated a possible mechanism for PCB-induced uterine contractions. In a series of experiments they discovered that the PCB mixture Aroclor 1242 can affect several cellular events known to be involved in the development of contractions in uterine muscle cells.

In one set of studies, Aroclor 1242 increased levels of the cellular messenger arachidonic acid in cultured uterine muscle cells. Enzyme inhibition experiments revealed that this activity was mediated by an enzyme known as phospholipase A2. Thus, the Aroclor 1242-induced release of arachidonic acid likely occurred through activation of phospholipid cell signaling pathways. Other experiments showed that Aroclor 1242 both increased the influx of intracellular calcium and activated voltage-operated calcium channels in uterine muscle cells, a significant finding because calcium is an essential stimulus for initiating uterine muscular contractions. Based on these findings, the scientists report "it is possible that arachidonic acid liberated by Aroclor 1242 activates voltage-operated calcium channels of [uterine muscle cells] and thus stimulates uterine muscle contraction."

PCBs have been associated with spontaneous abortion and shortened gestation length in women, wildlife and laboratory animals exposed to these industrial chemicals. Because premature birth is a considerable health problem in this country -- it accounts for 75% of newborn deaths not related to malformations -- it is important to determine how and to what extent PCBs may disrupt normal uterine functioning . The mechanistic understanding acquired in these studies is providing much needed insight into reproductive risks that may arise from PCB exposures.


For more information please contact:
    Rita Loch-Caruso, Ph.D.
    Toxicology Program
    Department of Environmental & Industrial Health
    University of Michigan, 1420 Washington Heights
    Ann Arbor, MI 48109
    Phone: (734) 936-1256, Email: rlc@umich.edu
To learn more about this research please refer to the following sources:
  • Bae, J., M. Peters-Golden, and R. Loch-Caruso. 1999. Stimulation of pregnant rat uterine contraction by the polychlorinated biphenyl (PCB) mixture Aroclor 1242 may be mediated by arachidonic acid release through activation of phospholipase A2 enzymes. J Pharmacol Exp Ther 289: 1112-1120.
  • Bae, J., E.L. Stuenkel, R. Loch-Caruso. 1999. Stimulation of oscillatory uterine contraction by the PCB mixture aroclor 1242 may involve increased [Ca2+](i) through voltage-operated calcium channels. Toxicol Appl Pharm 155: (3) 261-272.




    Susceptibility to infections and immune status in Inuit infants exposed to organochlorines.


    Dewailly, E., Ayotte, P., Bruneau, S., Gingras, S., Belles-Isles, M., Roy, R.
    Source: Environ Health Perspect 108:205-211 (2000).
    Abstract

    We investigated whether organochlorine exposure is associated with the incidence of infectious diseases in Inuit infants from Nunavik (Arctic Quebec, Canada). We compiled the number of infectious disease episodes during the first year of life for 98 breast-fed and 73 bottle-fed infants. Concentrations of organochlorines were measured in early breast milk samples and used as surrogates to prenatal exposure levels. Immune system parameters were determined in venous blood samples collected from infants at 3, 7, and 12 months of age. Otitis media was the most frequent disease, with 80.0% of breast-fed and 81.3% of bottle-fed infants experiencing at least one episode during the first year of life. During the second follow-up period, the risk of otitis media increased with prenatal exposure to p,pī-DDE, hexachlorobenzene, and dieldrin. The relative risk (RR) for 4- to 7- month-old infants in the highest tertile of p,pī-DDE exposure as compared to infants in the lowest tertile was 1.87 [95% confidence interval (CI), 1.07-3.26]. The RR of otitis media over the entire first year of life also increased with prenatal exposure to p,pī- DDE (RR, 1.52; CI, 1.05-2.22) and hexachlorobenzene (RR, 1.49; CI, 1.10-2.03). Furthermore, the RR of recurrent otitis media ( 3 episodes) increased with prenatal exposure to these compounds. No clinically relevant differences were noted between breast-fed and bottle-fed infants with regard to immunologic parameters, and prenatal organochlorine exposure was not associated with immunologic parameters. We conclude that prenatal organochlorine exposure could be a risk factor for acute otitis media in Inuit infants.



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