#175: Dioxin--Part 3: New Evidence That Dioxin Causes Human Cancers And Other Diseases.

=======================Electronic Edition========================

RACHEL'S HAZARDOUS WASTE NEWS #175
---April 4, 1990---
News and resources for environmental justice.
------
Environmental Research Foundation
P.O. Box 5036, Annapolis, MD 21403
Fax (410) 263-8944; Internet: erf@igc.apc.org ==========
RACHEL-4CM = DIOXIN FOCUSED DIRECTORY Remote Access Chemical Hazards Electronic Library. Dioxinnz.com ========================Original Source========================

Two recent studies, published in 1988 and 1989, have indicated a connection between exposure to dioxin and development of cancers in humans. Earlier studies had shown little evidence linking human cancers to dioxins, but these earlier studies have now been challenged by U.S. government officials as fraudulent. (See RHWN #171.) One of the recent studies also reveals a connection between dioxin exposure and a variety of non-cancer health effects, including heart attacks (among men), and digestive diseases, cirrhosis of the liver, gall bladder and biliary tract diseases, and genitourinary diseases (among women).

Seveso, Italy

On July 10, 1976, an industrial disaster occurred at a chemical plant operated by the pharmaceutical giant, Hoffman-La Roche, in the town of Meda, Italy. A visible chemical cloud containing dioxin (2,3,7,8-TCDD and other dioxins) spread over several square miles of populated countryside; most heavily hit was the community of Seveso. More than 200,000 people aged 20 to 74 lived in towns near the accident. Nearly 31,000 people aged 20 to 74 lived in zones contaminated to some degree by the accident and about 200 individuals had such high exposures that they developed chloracne, an acne condition known to be caused by exposure to dioxins.

A team of Italian physicians and researchers has been studying health conditions, including death certificates, of 30,703 people aged 20 to 74 living in areas termed "exposed," comparing people's experience there against a larger population of 167,391 individuals aged 20 to 74 living nearby in non-exposed areas. A recent report in the AMERICAN JOURNAL OF EPIDEMIOLOGY [1] reveals several elevated disease rates among the exposed group.

The report covers the decade 1976 to 1986, which is a short period in which to find cancer occurrences. All cancers exhibit a "latency period" (or delay period) between the time a cancer-causing exposure occurs and a cancer actually develops; the latency period varies from 7 to 40 or 50 years. Thus a study of cancers occurring 10 years after an exposure to cancer-causing chemicals could only reveal the earliest evidence of cancers and should be understood to be preliminary in nature.

The results of the study are reported for people living in three areas, labeled zones A, B and R. Zone A is closest to the accident site and zone R extends several miles distant; zone B is between the two. The assumption is that people's exposure varied with distance from the accident.

In zone A, women had elevated cancers of the gall bladder and biliary tract. They also had elevated occurrences of circulatory diseases and of chronic rheumatic heart disease. Men in zone A had elevated occurrence of cerebrovascular disease (such as stroke). In zone B, men had elevated melanomas (serious skin cancers) and cancers of the lining of the chest cavity (pleura); women in zone B had elevated incidence of soft tissue sarcomas. In zone R, men had elevated incidence of cancers of the lining of the chest cavity (pleura), and they had increased incidence of all blood diseases, and of cerebrovascular disease; women in zone R had increased incidence of cancer of the uterus, as well as hypertensive vascular disease.

The results reported above are averages for the entire decade. In the case of cancers, which would only begin to occur after a latency period, the timeperiod of interest is the second five years of the decade, and, accordingly, the Italian researchers reported results for each half of the decade.

During the second half of the decade: In zone A there were no elevated cancer levels. In zone B, men showed elevated incidence of cancers of the lung, cancers of the lining of the chest cavity (pleura), serious skin cancers (melanoma), Hodgkin's disease (cancer of the lymph nodes), and leukemia. In zone B, women showed increased incidence of soft tissue sarcomas and of the thyroid gland. In zone R, men showed elevated incidence of leukemia, and women showed elevated incidence of cancer of the brain. It is perhaps relevant to note that two previous studies have implicated brain cancer with exposure to dioxins in weed killers. [2, 3]

This study of the people exposed to dioxin during the Seveso accident does not prove that dioxin exposure caused the cancers or the other serious ailments from which these people suffer in abnormally high numbers (mainly diseases of the heart, blood, and arteries). Nevertheless, this study confirms that it is definitely misleading and untrue when anyone says there is "no evidence" of cancer or other serious diseases among humans exposed to dioxins. (In addition, an earlier U.S. government study has shown that Vietnam veterans exposed to Agent Orange [a weed killer contaminated with dioxin] suffer from elevated incidence of cancers, liver damage, cardiovascular deterioration, and degeneration of the endocrine system. See RHWN #73.)

Sweden

Phenoxyacetic acids (for example, the weed killers known as 2,4,5-T and 2,4-D) are almost always contaminated with dioxins during manufacture. During the late 1970s, Swedish researchers studied workers who had been exposed to phenoxyacetic acids and found increased incidence of soft tissue sarcomas (rare cancers of the connective tissues). [4, 5] During the mid'80s, several additional studies confirmed the relationship between soft tissue sarcomas and exposure to phenoxy herbicides, while other studies failed to confirm such a relationship. Now a new study has once again shown a three-fold increase in soft tissue sarcomas among workers exposed to phenoxy herbicides. [6]This is the tenth study that we know of showing a positive relationship between exposure to phenoxy herbicides and soft tissue sarcomas. [7] Five studies have failed to confirm such a relationship. [8]

How can one make sense out of conflicting reports, when 10 studies show that certain chemicals cause cancer and 5 studies show that those same chemicals do not cause cancer? How can the public know what policies make sense to pursue?

In our experience, people who make money manufacturing, or using, such chemicals prefer to argue that "we just don't know," and "until all the facts are in, we should not make any changes." Unfortunately, all the facts will never be in. People, including consumers buying phenoxy herbicides at the lawn-care store and politicians making laws, will always have to make decisions based on incomplete information.

From our viewpoint, the key question is this: Is it more important to protect people and the environment from damage, or to protect chemicals from regulation, control and outright bans?

--Peter Montague, Ph.D.

Also see: Dioxin--Part 1: Gauging the Toxicity of Dioxin. #171

Also see: Dioxin--Part 2: Gauging the Toxicity of Dioxin. #173

===============

[1] Pier Alberto Bertazzi and others, "Ten-year Mortality Study of the Population Involved in the Seveso Incident in 1976," AMERICAN JOURNAL OF EPIDEMIOLOGY, Vol. 129 (1989), pgs. 1187-1200.."

[2] A. Bair and others, "Lung Cancer and Other Causes of Death Among Licensed Pesticide Applicators," JOURNAL OF THE NATIONAL CANCER INSTITUTE Vol. 71 (1983), pgs. 31-37.

[3] D. Coggon and others, "Mortality of Workers Exposed to 2-methyl-4-chlorophenoxy-acetic acid." SCANDINAVIAN JOURNAL OF WORK, ENVIRONMENT AND HEALTH Vol. 12 (1986), pgs. 448-454.

[4] Olav Axelson and others, "Herbicide Exposure and Cancer Mortality," SCANDINAVIAN JOURNAL OF WORK, ENVIRONMENT AND HEALTH Vol. 6 (1980), pgs. 73-79.

[5] Lennart Hardell and others, "Malignant Lymphoma and Exposure to Chemicals, Especially Organic Solvents, Chlorophenols, and Phenoxy Acids: A Case-Control Study." BRITISH JOURNAL OF CANCER Vol. 43 (1981), pgs. 169-176.

[6] Lennart Hardell and others, "The Association Between Soft Tissue Sarcomas and Exposure to Phenoxyacetic Acids--A New Case-referent Study," CANCER Vol. 62 (1988), pgs. 652-656.

[7] Nine of the studies are listed in footnotes 1 through 9 of the Hardell study we cited in our footnote 6 (above), and the tenth study is the Hardell study itself cited in our footnote 6 (above).

[8] The five studies are listed in footnotes 10 through 14 of the Hardell study we cited in our footnote 6 (above).

Descriptor terms: seveso, italy; dioxin; gender; male; female; cancers; gall bladder; circulatory; heart disease; herbicides; agent orange; phenoxyacetic; hodgkins; lung; skin; pleural; sarcomas; uterine; leukemiea; brain cancer;

#173: Dioxin--Part 2: Gauging the Toxicity of Dioxin.

=======================Electronic Edition========================

RACHEL'S HAZARDOUS WASTE NEWS #173
---March 21, 1990---
News and resources for environmental justice.
------
Environmental Research Foundation
P.O. Box 5036, Annapolis, MD 21403
Fax (410) 263-8944; Internet: erf@igc.apc.org ==========
RACHEL-4CM = DIOXIN FOCUSED DIRECTORY Remote Access Chemical Hazards Electronic Library. Dioxinnz.com =================================Original Source========================

[Continuing our series on dioxin. Page numbers in parentheses refer to the ATSDR (the federal Agency for Toxic Substances and Disease Registry) Toxicological Profile for dioxin, cited in our last paragraph, below.]

It has become fashionable to pooh-pooh dioxin. We believe there are two reasons why this is occurring. First, some scientists have been publishing studies indicating that humans exposed to dioxin do not have an increased risk of cancer. As we saw in RHWN #171, some of the most important of these studies have now been exposed as fraudulent. The second reason is that dioxin is so toxic that it is difficult to express its potency in normal terms; therefore the media frequently print scary claims without offering much evidence, leading some people to conclude (incorrectly) that there isn't much substance to any claims about the extreme toxicity of dioxin.

In this series, we hope to lay the groundwork for an understanding of dioxin, to help people put dioxin into perspective. Some of what follows may seem a bit more technical than you are accustomed to reading in this newsletter; but stick with it, and you'll see why we have taken this approach.

The scientific and medical evidence presented by ATSDR forces us to conclude that dioxin deserves our greatest respect. It seems to be one of the two or three most toxic chemicals ever discovered, and it is produced as a byproduct of several different industrial processes. For years, industry has been dumping dioxin into the environment in large quantities without paying attention to the consequences. This does not mean there have been no consequences; it just means no one has made any systematic effort to tally them up.

Dioxin is a family of chemicals (75 in all) that does not occur naturally, nor is it intentionally manufactured by any industry (pg. 1). The most toxic dioxin is called 2,3,7,8-TCDD. Dioxins are produced as byproducts of the manufacture of some herbicides (for example, 2,4,5-T), wood preservatives made from trichlorophenols, and some germicides (for example, hexachlorophene). Dioxins are also produced by the manufacture of pulp and paper, by the combustion of wood in the presence of chlorine, by fires involving chlorinated benzenes and biphenyls (e.g., PCBs), by the exhaust of automobiles burning leaded fuel, and by municipal solid waste incinerators.

ATSDR says, "2,3,7,8-TCDD is highly toxic to all laboratory animals tested...." (pg. 11). Even the most conservative of toxicologists says, "TCDD has been called the most toxic synthetic chemical known to man. If its acute toxicity to the guinea pig, and even the rat and mouse, is the criterion, the statement is probably correct.... TCDD is unquestionably a chemical of supreme toxicity to experimental animals. Moreover, severe chronic effects from low dosages have also been demonstrated in experimental animals. Therefore, the concern about its effects on human health and the environment is understandable."[1]

In cases of high exposure of humans through industrial accidents, 2,3,7,8-TCDD causes a severe acne (called chloracne) which is not just a skin ailment; chloracne is a systemic disease that is more disfiguring than teenage acne and its effects last for years (in some cases, decades) after exposure (pgs. 3, 39).

There is "suggestive evidence" that 2,3,7,8-TCDD causes liver damage in humans (pgs. 3, 52-53). It definitely causes severe liver damage in animals.

In animals, 2,3,7,8-TCDD is toxic to the immune system; such effects have not been proven in humans (pgs. 3, 40, 54-56). In animals, 2,3,7,8-TCDD causes reproductive disorders, including spontaneous abortions. Monkeys are particuarly sensitive to reproductive effects from exposure to 2,3,7,8-TCDD. Such effects have not been proven in humans (pgs. 3, 17, 58-59). In animals, dioxin causes genetic damage (pgs. 60-61).

Both the U.S. Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC) have concluded that dioxin is a "probable human carcinogen" (pgs. 7, 61-68, 94). As we saw in RHWN #171, scientists within EPA have asked that this question be reviewed again because some of the key studies of dioxin and cancer were fraudulent, and EPA has relied on these fraudulent studies to set current standards.

How can we judge the toxicity of dioxin (or of any chemical, for that matter)? One way is to look at the standards that have been set by regulatory agencies.

In the case of dioxin, EPA has calculated a "safe" dose, taking into consideration dioxin's ability to cause cancer. The "safe" dose is expressed in extremely small units: femtograms. There are 28 grams in an ounce, and one femtogram is 0.000,000,000,000,001 grams, or one quadrillionth of a gram, or 10**-15 (or, 10 raised to the power of negative 15) grams.

EPA believes that ingesting (eating) 6.4 femtograms (6.4 x 10**-15 grams) of 2,3,7,8-TCDD per kilogram of body weight per day would cause cancer in one in a million people so exposed (pg. 95). Since an average adult weighs 62 kilograms or 137 pounds (average men weigh 70 kilograms [154 pounds] and average women weigh 55 kg [120 pounds]), the EPA is saying that 397 femtograms of 2,3,7,8-TCDD consumed in food each day would kill one-in-a-million humans so exposed. Over a year's time, 397 femtograms per day add up to 145,000 femtograms; over a 70-year lifetime, this would add up to 10.1 million femtograms, so 10.1 million femtograms (or 0.01 micrograms) is the maximum amount you could safely get into your body during your entire lifetime, EPA believes.

How can we express this in terms that people can grasp?

Let's compare it to one single aspirin tablet. One aspirin tablet weighs 5 grains (or 325 milligrams, or 325 trillion femtograms), so to express one "safe" lifetime dose of 2,3,7,8-TCDD, you would take a single aspirin tablet and divide it into 32 million (actually 32,172,218) miniscule pieces. Then one of those tiny pieces would represent one "safe" lifetime dose of 2,3,7,8-TCDD.

Another comparison: A single grain of table salt weighs approximately 0.1 milligrams or 100 billion femtograms, so to get an amount of table salt that weighs the same amount as one "safe" lifetime dose of 2,3,7,8-TCDD, you would divide a single grain of table salt into 9,900 microscopic pieces. One of those tiny pieces would represent a "safe" lifetime dose of dioxin.

The U.S. Food and Drug Administration (FDA) has its own way of calculating the same one-in-a-million cancer risk and they believe the EPA has overestimated the hazard by a factor of 10. In other words, FDA believes you could represent a "safe" dose of 2,3,7,8-TCDD by dividing a single grain of table salt into 990 pieces, with one of those pieces representing a safe lifetime dose. The federal Centers for Disease Control (CDC) in Atlanta has done its own calculation, concluding that the cancer hazard from dioxin is about half-way between the EPA's estimate and the FDA's estimate. EPA says 6.4 femtograms per kilogram of body weight per day is the safe dose; CDC says the correct number is 27.6; FDA says it's 57.2 (pg. 95). No matter which agency does the calculation, there's no escaping the fact that dioxin is considered supremely toxic.

One other way to understand the toxicity of dioxin is to compare the dioxin "reference dose" established by EPA to the "reference dose" they have set for other common toxic materials. The "reference dose" is the highest amount they believe you could eat regularly without incurring any disease (not considering cancer).

The reference dose for dioxin is 0.000,000,001 milligrams per kilogram of body weight per day (mg/kg/day) (pg. 94); the reference dose for the toxic metal cadmium[2] is 0.001 mg/kg/day and the "reference dose" for the toxic metal arsenic[3] is the same as for cadmium.[2] Thus we can see that EPA considers dioxin in food 1,000,000 times (one million times) more toxic than cadmium or arsenic[3], not counting the cancer hazard from dioxin. Yes, dioxin is toxic, no doubt about it.

[Part 3 continued issue #175 ]

--Peter Montague, Ph.D.

Also see: Dioxin--Part 1: Gauging the Toxicity of Dioxin. #171

===============

[1] Fred H. Tschirley, "Dioxin," SCIENTIFIC AMERICAN Vol. 254 (February, 1986), pg. 34."

[2] Agency for Toxic Substances and Disease Registry, TOXICOLOGICAL PROFILE FOR CADMIUM (Springfield, VA: National Technical Information Service [NTIS], 5285 Port Royal Rd., Springfield, VA 22161; phone (703) 487-4650), pg. 76.; NTIS number PB89-194476. $21.95.

[3] Agency for Toxic Substances and Disease Registry, TOXICOLOGICAL PROFILE FOR ARSENIC (Springfield, VA: National Technical Information Service [NTIS], 5285 Port Royal Rd., Springfield, VA 22161; phone (703) 487-4650), pg. 92.; NTIS number PB89-185706. $21.95.

Get: Agency for Toxic Substances and Disease Registry, TOXICOLOGICAL PROFILE FOR 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (Springfield, VA: National Technical Information Service [NTIS], 5285 Port Royal Rd., Springfield, VA 22161; phone (703) 4874650); NTIS number PB89-214522. $21.95.

Descriptor terms: dioxin; atsdr; herbicides; wood preservatives; trichlorophenols; hexachlorophene; pulp and paper; pcbs; msw; incineration; skin disorders; liver; fda; health effects; sudies; reproductive disorders; miscarriages; genetic disorders; cancers; risk assessment; chloroacne;

#171: Dioxin--Part 1: Dioxins And Cancer: Fraudulent Studies.

=======================Electronic Edition========================

RACHEL'S HAZARDOUS WASTE NEWS #171
---March 7, 1990---
News and resources for environmental justice.
------
Environmental Research Foundation
P.O. Box 5036, Annapolis, MD 21403
Fax (410) 263-8944; Internet: erf@igc.apc.org ==========
RACHEL-4CM = DIOXIN FOCUSED DIRECTORY Remote Access Chemical Hazards Electronic Library. Dioxinnz.com ========================Original Source========================

For years, industry scientists have been claiming there's no evidence that dioxins cause cancer in humans. Now there is mounting evidence that such claims rely heavily on studies that are fraudulent. Two companies recently accused of producing fraudulent dioxin-and-health data are Monsanto and BASF.

Monsanto

A scientist with U.S. Environmental Protection Agency (EPA) says Monsanto falsified data in important studies that Monsanto used to support its claim that dioxin does not cause cancer in humans. Dr. Cate Jenkins, a chemist in EPA's Office of Solid Waste and Emergency Response, says EPA itself relied upon Monsanto's fraudulent data in setting health standards for dioxin, and Jenkins has asked the EPA's Science Advisory Board to reopen the matter of EPA's dioxin standards, to take a fresh look at available data.[1]

Two important sources of dioxins in the environment are old chemical dumps and the incineration of municipal solid wastes,[2] which is why EPA is concerned about allowable levels of human exposures to dioxin.

BASF

The British technical journal, NEW SCIENTIST, says, "A new analysis by a West German epidemiologist may have established the first clearcut evidence of a direct link between exposure to dioxins and cancer in humans. Friedemann Rohleder, an independent specialist, has produced a report detailing an unexpectedly high incidence of cancer among workers exposed to dioxins during an industrial accident at a chemicals plant in 1953.[3]

"The plant, operated by the West German company BASF, made trichlorophenol. Rohleder claims the company presented the data in a way that disguised the cancers," says NEW SCIENTIST.

Background

Each of these claims of fraud relates to an industrial accident in which workers were exposed to dioxins; follow-up medical studies funded by the responsible companies have been published in mainstream scientific journals, claiming to show that no excess cancers have occurred in the dioxin-exposed workers. In fact, excess cancers have occurred, but it appears that the data have been manipulated to hide the facts.

The Monsanto Case

In 1949, an explosion occurred at a Monsanto chemical factory in Nitro, West Virginia; as a result, many workers in the plant were exposed to the herbicide 2,4,5-T, which was contaminated with dioxin. (This herbicide was later the principal component of Agent Orange, the chemical defoliant used by the U.S. in Viet Nam.) In subsequent years, two Monsanto scientists, J.A. Zack and R. W. Gaffey, studied the exposed workers, comparing their health against the health of a similar group of workers who were not exposed to dioxin or 2,4,5-T.[4]

According to court documents attached to the EPA memo,"Zack and Gaffey deliberately and knowingly omitted 5 deaths from the exposed group and took four workers who had been exposed and put these workers in the unexposed group, serving, of course, to decrease the death rate in the exposed group and increase the death rate in the unexposed group."

Other studies of this same accident were also fraudulent, according to the same court documents, including a study by R.R. Suskind published in the JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION:[5] "This published study of the workers exposed in the 1949 accident reported only 14 cancers in the exposed group and 6 in the unexposed group (a smaller cohort). However, the medical records produced [by Monsanto] to the Plaintiffs conclusively prove gross miscalculations and omissions... there were 28 cancers in the group that had been exposed to dioxins in 1949 as opposed to only 2 cancers in the unexposed group." Mr. Suskind published two other reports [6,7] on the same accident, using his same data, to reach the conclusion that dioxin does not cause cancer.

The BASF Case

On the night of November 17, 1953, a runaway chemical reaction spewed dioxin-contaminated chemicals over workers and community residents of two small German cities, Mannheim and Ludwigshafen. Subsequently, an epidemiological study was used to deny workers any compensation for ailments they claimed they suffered as a result of exposure. In keeping with German law, the workers retained their own expert to review the data. Their expert, Friedemann Rohleder, received the data from the German government but found, to his surprise, that all the data actually came from the BASF company itself. He analyzed the data and found that some workers suffering from chloracne, which is universally acknowledged to be evidence of high exposure to dioxin, had been placed in the low-exposure or non-exposed group. He found evidence of "diluting" the exposed group with 20 plant supervisory staff who, Rohleder believes, were not exposed. When Rohleder omitted the 20 supervisory staff, his analysis revealed statistically significant increases in two groups of cancers: cancers of the respiratory organs (lungs, trachea, etc.), and cancers of the digestive tract. "This analysis adds further evidence to an association between dioxin exposure and human malignancy," Rohleder told NEW SCIENTIST.

[continued see issue #173 ]

--Peter Montague, Ph.D.

===============

[1] Cate Jenkins, "Memo to Raymond Loehr: Newly Revealed Fraud by Monsanto in an Epidemiological Study Used by Epa to Assess Human health Effects from Dioxins," dated February 23, 1990. Jenkins is a chemist with the Waste Characterization Branch (OS 332), Characterization and Assessment Division, U.S. EPA, 401 M St., SW, Washington, DC 20460. Loehr is Chairperson of the Executive Committee of the Science Advisory Board (A-101), Office of the Administrator, U.S. EPA, 401 M St., SW, Washington, Dc 20460. The Jenkins memo has attached to it 25 pages of a brief filed in Case No. 5-88-0420, in the Appellate Court of Illinois, Fifth District by attorneys suing Monsanto on behalf of plaintiffs who say they were harmed when a Norfolk and Western railroad tank car derailed, spilling 19,000 gallons of a Monsanto chemical called "ocp-crude" into the community of Sturgeon, Missouri the night of January 10, 1979. Chief attorney for the plaintiffs is Rex Carr, 412 Missouri Avenue, East St. Louis, Il 62201; phone (618) 274-0434. Our thanks to Margo Blackwell, People Against the Incinerator (pati), Bloomington, Indiana, and to Epa official William Sanjour, both of whom independently sent us the information about Monsanto. We can mail copies of the Jenkins memo and attachments (28 pages) for $14.00, which covers our actual costs of photocopying, handling and mailing.

[2] Oak Ridge National Laboratory. TOXICOLOGICAL PROFILE FOR 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN [ATSDR/TP-88/23; PB89-214522] (Springfield, VA: National Technical Information Service, June, 1989), pg. 22, identifies dumps and incinerators as "the important sources of 2,3,7,8-TCDD exposure to the general population." This is the Agency for Toxic Substances and Disease Registry [ATSDR] toxicological profile for dioxin (See RHWN #169.)

[3] Stephanie Wanchinksi, "New Analysis links dioxin to cancer," NEW SCIENTIST October 28, 1989, pg. 24. Thanks to Paul Connett of Work on Waste USA, we have a copy of Friedemann Rohleder's paper, which he presented in late September at a dioxin conference in Toronto, Ontario; Rohleder's paper is entitled "Dioxins and Cancer Mortality-Reanalysis of the BASF Cohort." We can mail you the 14-page Rohleder paper for $7.00, or you can request a copy directly from the author: Friedemann Rohleder, Friedrich Hebel Str. 13, 1712 Werne, West Germany.

[4] Zack, J.A., and W. R. Gaffey, "A Mortality Study Of Workers Employed At The Monsanto Company Plant In Nitro, West Virginia," ENVIRONMENTAL SCIENCE RESEARCH, Vol. 26 (1983), pgs. 575-591.

[5] R.R. Suskind, and V.S. Hertzberg, "Human Health Effects Of 2,4,5-T And Its Toxic Contaminants," JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION, Vol. 251, No. 18 (1984), pgs. 2372-2380.

[6] R.R. Suskind, "Chloracne, 'The Hallmark Of Dioxin Intoxication,'" SCANDINAVIAN JOURNAL OF WORK, ENVIRONMENT AND HEALTH, Vol. 11, No. 3 (1985), pgs. 165-171.

[7] R.R. Suskind, "Long-Term Health Effects Of Exposure To 2,4,5-T And/Or Its Contaminants," CHEMOSPHERE, Vol. 12, No. 4-5 (1983), pg. 769.

Descriptor terms: dioxins; monsanto; basf; cancers; trichlorophenol; occupational safety and health; nitro, wv; va; herbicides; studies; chloracne; skin disorders; lung cancer; respiratory cancer; digestive tract;

#219: Dioxin--Part 4: New Study Links Dioxin to Human Cancer. (dioxin)

=======================Electronic Edition========================
RACHEL'S HAZARDOUS WASTE NEWS #219
---February 6, 1991---
News and resources for environmental justice.
------
Environmental Research Foundation
P.O. Box 5036, Annapolis, MD 21403
Fax (410) 263-8944; Internet: erf@igc.apc.org ==========
RACHEL-4CM = DIOXIN FOCUSED DIRECTORY Remote Access Chemical Hazards Electronic Library. Dioxinnz.com =======================ORIGINAL SOURCE========================

A new study published last month provides fresh evidence that dioxin [TCDD] causes cancer in humans. Dioxin is not a commercial product but is created as an unwanted byproduct of many industrial processes; significant quantities of dioxin are released from the smoke stacks (and the ash landfills) of incinerators that burn chlorine-containing items--such as medical wastes (RHWN #179), sewage sludge, and municipal solid wastes. Once it is released into the environment dioxin persists for a very long time, enters food chains, and accumulates; when humans eat dioxin contaminated food, such as milk or fish, the humans themselves accumulate dioxin in their blood and fatty tissues. [1]

Scientists have known since the mid-1960s that dioxin is an extremely powerful promoter of cancer in laboratory animals, but industry researchers have recently been claiming that humans somehow are exempt from the dioxin danger. The question of dioxin's hazard to humans took on real urgency in the early '80s when 15,000 veterans sued Dow chemical and other producers of Agent Orange (a dioxin-contaminated herbicide widely used to defoliate the jungle in Vietnam from 1962 to 1971); the vets sought money damages for health effects (cancer, defective offspring, and so forth) they said they were experiencing. Lawyers for the Vietnam vets offered documentary evidence that Dow chemists convened a private meeting of their competitors in 1965 to share new information that impurities [dioxins] in the herbicide 2,4,5-T (principal component of Agent Orange) caused severe liver damage in rabbits. According to court records, a chemist at Hercules Powder Company who attended the private Dow meeting in 1965, received a phone call from a Dow executive who "warned him to keep the findings away from the federal government," according to a reporter for Nature, the British science journal. [2] If this is true, it would not be the first time, nor the last, that money has influenced the outcomes, and the uses, of scientific studies.

In any case, as a result of these lawsuits, during the 1980s the question of dioxin's effects on humans became subject of bitter controversy--with enormous sums of money riding on the outcome of the debate. As the 1980s drew to a close and it became known that all incinerators create and release dioxin into the local environment, industry felt enormous pressure to "prove" that dioxin was harmless to humans. From 1980 onward, industry researchers published several studies of dioxin-exposed workers, claiming to show that they suffered no more cancer than the general public. Last year, however, evidence began to accumulate indicating that the industry-funded studies of dioxin dangers to humans were badly flawed or were simply fraudulent (see RHWN #171, #173, #175).

The latest study is not by industry researchers but by Dr. Marilyn Fingerhut of the federal National Institute for Occupational Safety and Health (NIOSH); Fingerhut looked at the health of 5172 workers at 12 chemical plants that manufacture (or formerly manufactured) products contaminated with dioxin such as the herbicides 2,4,5-T, Silvex, Ronnel, Erbon, and pentachlorophenol (which has also been used as a fungicide, algicide, and wood preservative for telephone poles and pilings), and the bacterial cleansing agent, hexachlorophene--until the 1970s, a leading bactericide in hospitals.

Of the 5172 exposed workers (all of whom were male), 1520 met two key conditions: they had been exposed for at least a year, and their exposure had begun at least 20 years previously. The onset of cancer is always delayed by 7 to 40 years (or more) between the time of initial exposure and the time disease appears; therefore, the "latency" period of at least 20 years is important in studying cancer that may be related to a particular chemical exposure. This group ("cohort," to use the language of medical researchers) had nine times (900%) the normal amount of soft tissue sarcoma--malignant cancer of the soft connective tissues. The same group also had 42% more cancers of the respiratory tract (trachea, bronchus and lung) than would be expected among males in the general public; by various means, Dr. Fingerhut examined and tried to eliminate the possibility that tobacco smoking explained the increase in respiratory cancers.

Among the entire cohort of 5172 men, the occurrence of all cancers was significantly increased, by 15%; in the high-exposure group of 1520 men, the "all cancers combined" increase was even more pronounced--46%; furthermore "all cancers combined" were increased among workers at nine of the 12 plants studied. Even when cancers of the respiratory tract were omitted in an attempt to eliminate smoking as a possible the cause, "all cancers combined" was increased among the 5172 and even more so among the high-exposure 1520.

Dr. Fingerhut says correctly that her results do not prove that dioxin causes cancer in exposed workers. The workers she studied were exposed to many other chemicals, in addition to dioxin, on the job, and these other chemicals could explain the cancer increases she observed.

Nevertheless, the Fingerhut study makes it ever more difficult for the purveyors of dioxin-creating machines (such as incinerators for solid waste, hazardous waste, or sewage sludge) to claim that their dioxin emissions are negligible or harmless. Because dioxin accumulates in the food chain, even small amounts can build up to significant levels as time passes.

An editorial in the NEW ENGLAND JOURNAL OF MEDICINE tried to shed light on the meaning of the Fingerhut study the day it appeared. [3] The well-known Canadian biostatistician, John Bailar, wrote, "This evidence is short of proof, as the authors explain, but it must be taken seriously as a flag of a probable human risk. If one accepts the best estimate of excess risk given here (3 deaths observed among the 1520 workers minus 0.3 expected deaths equals 2.7), the lifetime risk of death from TCDD-related soft-tissue sarcoma is already approaching 2 per 1000 workers, and it may increase with additional follow-up study. This estimate falls in a range that is widely considered unacceptable for occupational hazards, and it is far in excess of the usual limits for lifetime risk to the public of 1 per 100,000 or 1 per million. "Despite the problems, which Fingerhut et al. carefully note, this work is a model of its kind. Occupational cohort studies are inherently difficult and uncertain, and we are likely to wait a long time for appreciably better or broader evidence of the effects of TCDD [dioxin] on human health....

"The hypothesis that low exposures [to dioxin] are entirely safe is distinctly less tenable now than before," Dr. Bailar said.

--Peter Montague, Ph.D.

===============

[1] Bengt-g"ran Svensson and others, "exposure to Dioxins and Dibenzofurans Through the Consumption of Fish." NEW ENGLAND JOURNAL OF MEDICINE Vol. 324 (Jan. 3, 1991), pgs. 8-12.."

[2] Peter David, "Dioxin--When was the Danger Known?" NATURE Vol. 303 (May 12, 1983), pg. 104.

[3] John C. Bailar III, "How Dangerous is Dioxin?" NEW ENGLAND JOURNAL OF MEDICINE Vol. 324 (Jan. 24, 1991), pgs. 260-262.

And get: Marilyn A. Fingerhut and others, "Cancer Mortality in Workers Exposed to 2,3,7,8-Tetrachlorodibenzo-p-dioxin," NEW ENGLAND JOURNAL OF MEDICINE Vol. 324 (Jan. 24, 1991), pgs. 212-218. Reprints free from Dr. Fingerhut at: Industrywide Studies Branch, Division of Surveillance, National Institute for Occupational Safety and Health, Centers for Disease Control, 4676 Columbia Parkway, Cincinnati, OH 45226.

A more complete report of this research is available under the title MORTALITY AMONG U.S. WORKERS EMPLOYED IN THE PRODUCTION OF CHEMICALS CONTAMINATED WITH 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD). Springfield, VA: National Technical Information Service (NTIS), Dec., 1990. Available from NTIS, 5285 Port Royal Rd., Springfield, VA 22161; phone (703) 4874650); NTIS number PB91-125971. $15.00 + shipping.