Dioxins (Doc Index)
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Dioxin is both a general, and a specific name. The chemical industry refers to a substance as a dioxin if it is one of the 74 known members of the chemical compound family known as Polychlorinated Dibenzo-para-dioxins (PCDDs). Very closely related and virtually identical in health effects are the 135 known members of the furan family, Polychlorinated Dibenzofurans (PCDFs) and some members of a closely related family of Polychlorinated Biphenyls (PCBs). The similarities are so close that these are collectively referred to in the public literature by the common name of 'dioxins'.
The dangers of dixons emerged following the return of soldiers and airmen from the Vietnam war. The American airforce sprayed 4.5 million acres of land/forest with this defoliant during the war. Different defoliant mixes were known by different Code Colours, and Agent Orange was a powerful mixture defoliants used to eliminate forest cover for North Vietnamese and Viet Cong troops. It also destroyed any crops that might be used to feed them.
This program of defoliation, was codenamed Operation Ranch Hand, and from 1961 to 1972 they sprayed more than 19 million gallons of herbicides over Vietnam. Unfortunately it contained traces of the contaminant dioxin mainly because if was made cheaply with little attention to purity or safety. Incinerators create dioxins, and many chlorine-chemical processes will also produce dioxins if the temperature isn't carefully controlled.
Agent Orange was the most commonly used of the herbicide mixtures, and the most effective: it was a 50-50 blend of 2,4,-D and 2,4,5-T. Almost every soldier or airman handling the defoliant had minor chloracne (chlorine related acne) - varying in intensity from teenage acne to extreme rashes. However it was discovered later that the dioxins caused serious health effects–including tumors, birth defects, rashes, psychological symptoms and cancer. This began to show up among the returned servicemen and their families, as well as among the Vietnamese population who had to continue to live and farm on dioxin-contaminated land.
The efforts of the chemical companies to deny that dioxins were dangerous (partly with the complicity of the American government) delayed recognition of how serious the problem was for decades. The chemical companies used all the same tactics as the tobacco industry -- funding fake research among science-for-sale entrepreneurs, hiring lobbyists and academics to promote the 'unproven danger' line, and bribing officials and politicians. In fact the same cadre of scientists who did the tobacco industry's bidding turn up in the dioxin business.
Documents & Timeline
Base data from Robert Allen's The Dioxin Wars and also from the dissertation of Joe Greene Conley II [2]
1872: German chemists synthesise octachlorinated dibenzo-pdioxin.
1897: Chloracne – a skin disease associated with dioxin exposure – identified.
1900: Herbert Dow, founder of Dow Chemical, credited with modern chlorine chemistry.
1918: Outbreak of chloracne following exposure to chlorinated naphthalenes.
1920–40: Dramatic increase of polychlorinated dibenzo dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) levels in north American lake sediments (reported 1984).
1929: Production of polychlorinated biphenyls (PCBs) begins, in USA.
1936: Production of Pentachlorophenol begins.
1940–47: Synthesis of 2,4,5-T and 2,4-D for US military use.
1949: Explosion at Monsanto trichlorophenol factory in Nitro, Virginia, USA.
1950: Dow begin 2,4,5-T production and discover toxic impurity in the process.
1952: US military contact Monsanto for information on the toxicity of 2,4,5-T.
1953: Explosion at Boehringer trichlorophenol factory in Hamburg, Germany.
1953: Explosion at BASF trichlorophenol factory in Ludwigshafen, Germany.
1956: Explosion at Rhone Poulenc trichlorophenol factory in Pont de Claix, France.
1956: ‘Accident’ at Hooker Chemicals trichlorophenol factory in Niagara Falls, USA.
1957: Tetra chloro dibenzo dioxin (TCDD) – the most toxic dioxin – identified as unwanted contaminant in production of chlorophenols.
1959: ‘Accident’ at Thompson Hayward trichlorophenol factory, New Jersey, USA.
1961: Further research relates TCDD to chloracne and liver damage.
1961: US military and trichlorophenol producers collaborate on production of 50:50 blend of 2,4,5-T and 2,4-D – Agent Orange
1963–70: Agent Orange used in Southeast Asia.
1963: Explosion at Philips Duphar trichlorophenol factory in Amsterdam, The Netherlands.
1963: Biologist Rachel Carson’s book Silent Spring is published and becomes a best seller. Carson brought to public attention the insidious impact on wildlife and ecosystems of aldrin, chlordane, dieldrin, DDT, endrin, lindane, pentachlorophenol, 2,4-D and 2,4,5-T. She described how pesticides and related chemicals were infiltrating ecosystems, and how they accumulated in the food chain with devastating results - which must inevitably extend to humans.
1964: Dow identify TCDD in 2,4,5-T.
1965–66: Sixty volunteers at Holmsburg prison in US treated with dioxin experience no immediate ill effects until dosage is increased 1,000-fold.
1965 Dow Chemical conducted a series of dioxin experiments on prisoners incarcerated in Holmsberg Prison PA. Under the direction of V K Rowe of Dow, Dr Albert Kligman was given $10,000 to conduct his experiments—putting a specific amount of pure dioxin on the backs of these human guinea pigs. Dr Kligman even increased the dosage dramatically at one point without Dow's knowledge This is important for two reasons: After the prisoners were released some came to the EPA for help. They were quite sick
The EPA rejected their claims and lost their files - even though major testimony about these experiments came to light. In 1980 EPA hearings, Mr Rowe testified about them. No moral outrage here. Rowe refused to follow up on the state of these prisoners: would not conduct anything close to a medical exam, and the matter was dropped
The result? Dow Chemical could continue to claim that beyond a case of chloracne, there is nothing wrong with anyone exposed to Agent Orange The EPA blew a powerful opportunity to check on a controlled body of men with known exposure—and didn't.
Dow Chemicals invited other manufacturers of Agent Orange and other related herbicides to a meeting in their Midlands headquarters and showed them the evidence of dioxin's cancerous and mutagenic potential in their own laboratory test animals. Dow and some of the other manufacturers agreed to use a new German process which could reduce dioxin levels in their herbicides to under 1 ppm. The other's didn't change. [3]
1965–66: Reproductive and developmental effects noted in North American Great Lakes fish-eating birds.
1966 Old dumped electrical equipment in land-fills began leaking coolants into the environment. This coolantl made by Monsanto had a contaminant known as Polychlorinated Biphenyls (PCBs). A chemist at the University o Stockholm, Soren Jensen, during his investigations into the environmental accumulation of DDT and other chlorinated pesticides in humans and wildlife, discovered that PCBs were also accumulating in Sweden's wildlife. Now PCBs were also becoming a toxic hazard in the environment.
1966: US military demand for Agent Orange reaches limit of industry capacity.
1967: Monsanto analyse their 2,4,5-T for TCDD contamination.
Jensen's finding (which had been largely discounted) that PCBs were now widely distributed in the pristine Swedish environment was confirmed by Shell Chemicals in the UK. Monsanto immediately sent a 'fire-fighting' team from Brussels to Sweden to talk to Jensen and win his cooperation in managing the public debate. [4] However the story leaked out as further investigators discovered PCBs in the environment; it was accumulating in the food chain of birds and threatening certain species.
1968: PCB/PCDF contamination of rice oil in Yusho, Japan. (Polychlorinated Biphenyl/Polychlorinated Dibenzofuran)
1968: Explosion at Coalite trichlorophenol factory in Bolsover, England.
1969: Bionetics Research Laboratories report reveals 2,4,5-T as teratogenic (birth deforming) in mice.
The growing concern over PCB's led Monsanto to implement a strategy to respond to regulatory pressures. The company's "Ad Hoc Committee on Aroclors" (used in electrical equipment) was set up to maintain sales and profits from these PCB-containing chemicals and defeat attempts to regulate them further. They also began to clean up leak problems around plants, and to moving manufacturing to chemicals thought to be less hazardous. However they still had the problem of future liability from past problems.
Monsanto's Chicago BioTest group (a large private testing firm) was asked to establish an animal testing program for PCBs, which would consider the problem "from public relations, DDT Wisconsin hearings, legal actions, and scientific aspects." (Their order of priorities).
1970: English scientists contract chloracne and high cholesterol levels after synthesising dioxin in their laboratory.
1970–71: Thomas Whiteside articles on phenoxy herbicides appeared in the New Yorker.
TCDD found to cause birth defects in mice. Poisoning of Missouri, USA.
The media now begins treating PCBs as "DDT-like compounds" The New York Times headlines its article (Sep 26 1971) "If You Think DDT's a Problem, Meet PCB" Both chemicals were being treated like radioactive fallout. Congressman William Ryan of New York proposed a total ban on PCBs.
1972–76: An acceptable hypothesis as to how dioxin reacts in the body through AH receptor was developed.
1973: Poly brominated biphenyls (PBBs) accidentally added to cattle feed in Michigan, USA.
1973The EPA defeated Dow Chemical's court challenge to their restrictions on 2,4,5-T and announced that it was totally banning the herbicide including its use on rice crops and for forest management.
1974 The EPA now postponed its total ban on 2,4,5-T because it didn't have the analytical capability of detecting minute levels of dioxins. However TCDD was found in breast milk from South Vietnam.
1976 July 10: Seveso Incident: An explosion at the Hoffman La Roche trichlorophenol factory in Meda (Seveso), Italy proved devestating.
A much later report from one of the field investigators.
The accident liberated kilogram amounts of TCDD near Seveso, Italy, and contaminated a wide area (whose population had been examined several times previously). Because of a lack of technology for measuring concentrations of dioxin in people we could only guess the levels by relating them to concentrations of TCDD in soil
The A-zone (736 people) was more contaminated than the B-zone (4737 people). Starting from 1988 we have been able to measure TCDD in serum samples which have been kept frozen at -30 C in the Desio Laboratory since 1976.
To review indirect with direct dose-effects we have examined children bom in the A-zone after 1977. In the 74 total births that occurred from 9 months after the accident (April, 1977) to December, 1984 (corresponding to about one TCDD half-life in adults), there was an excess of females (26 males vs 48 females) X' test; p<0-001).
This ratio declined (60 males vs 64 females) in the years from 1985 to 1994 and was no longer significant. In families with both parents from the A-zone, we have investigated the TCDD serum concentration in samples drawn in 1976. Our results show that high TCDD exposure in both parents is associated with an excess of female offipring (table).
[University Department of Clinical Pathology. Hospital of Deslo, 20033 Dealo-Mllan, Italy; and Division of Environmental Health Laboratory Sciences. Center for Envionmemal Health and Injury Control, Center for Disease Control and Prevention, Atlanta, Georgia. USA] [5]
1977–79: Lennart Hardell and Olav Axelson health studies of phenoxy herbicide exposed workers in Sweden.
1977: TCDD found to cause cancer in rats.
1978: TCDD found in emissions from domestic waste incinerators.
1978 Local Michigan representatives informed FDA's Detroit District that they had presumptively detected dioxins in the Tittabawasse and Saginaw Rivers which take the outflow from Dow Chemicals factory. The EPA estimated about 300 ppt parts per trillion -- very high! -- total dioxin in the river water. The EPA obtained 21 fish samples from the Michigan Department of Natural Resources taken from both rivers They found high levels of TCDD from 11 to 153 ppt and did nothing about their findings.
1978 When the Department of Defense decided there was no legitimate domestic use for Agent Orange, they decided to burn thousands of barrels left over from the war at sea off Johnson Island, a Pacific atoll. Enter the EPA with major advice for taking care of the personnel on board the incineration ship Vulcanus. Agent Orange was to be burned there at 1,000 degrees C. The EPA 1978 manual said.
The highly toxic contaminant present in Herbicide Orange is 2,3,7,8-tetrachlorodibenzo-p-dioxin The US Air Force has analyzed Herbicide Orange stocks and found TCDD concentrations ranging from 0.05 to 47 ppm [parts per million] Times Beach was evacuated at 2 ppb—parts per billion Pooled stocks would have an estimated average TCDD concentration of 1.9 ppm
The principal Herbicide Orange constituent of concern TCDD has been found to be highly embryotoxic teratogenic tending to cause developmental malfunctions and monstrosities, and acnegenic and is lethal in the microgram-per-kilogram of body weight range [emphasis added] The effects observed on workers are summarized below—to emphasize the need for personnel hygiene: chloracne moderate to severe skin irritation with swelling hardening blackheads pustules and pimples; hyperpigmentation skin discoloration); muscular pain; decreased libido fatigue nervous irritability intolerance to cold destruction of nerve fibers and nerve sheaths
In addition effects on exposed test animals...may be considered possible effects on the human system especially when the metabolism of the animal is similar to that of man These effects include toxicity to embryos birth defects possible carcinogenity and even death It should also be noted that the greatest hazard is to pregnant females and their fetuses especially in the first third of the pregnancy period
The manual then spoke of the ways of entry of TCDD into the body: through mouth—ingestion; through the skin—percutaneous; through the lungs and eyes.
If this weren't enough the manual was put together with the cooperation of Dow Chemical's Rowe who had been Dow's point man in telling all the customers that there were no problems with their herbicides, while secretly writing to all Dow management that TCDD is the most toxic material we've ever studied. Add the Department of Defense and the US Air Force Environmental Health Labs to the committee
The manual then goes on to describe in great detail just what kind of precautions the workers on board the Vulcanus must take to ensure safety and then what to do should a worker become exposed: Decontaminate him immediately; speed is essential.
1979 The problem of Times Beach returned. The EPA was tipped off that the pesticide company Northeastern Pharmaceutical and Chemical Co (NEPACCO) had buried toxic wastes in the area. They uncovered 90 corroded and leaking drums of waste with very high levels of dioxins (up to 2000 ppm). However little was done other than removing the waste.
Thomas Whiteside, who had kept studying the birth-deforming effects of 2,4,5-T now published, "The Pendulum and the Toxic Cloud: The Course of Dioxin Contamination" (New Haven: Yale University Press.
A Class action was filed against seven US manufacturers of Agent Orange, including Dow and Monsanto, and the US EPA suspends use of herbicide 2,4,5-T.
1979: PCB/PCDF contamination of rice oil in YuCheng, Taiwan.
1979: Association of rare cancers – soft tissue sarcomas – with TCDD and phenoxyacetic acids.
1979: TCDD found to modulate hormones and their receptors.
1980: Toxic contamination of Love Canal community revealed.
1980 Oct The Dioxin Wars by Robert Allen (Sunday Times, UK) says:
Monsanto tacitly acknowledged the importance of the Gaffey/ Zack study when, in October, 1980, three years before the study was published, the company issued a press release headlined, "Study Fails to Link Agent Orange to Deaths of Industrial Workers."
[Bill] Gaffey’s study was important to Monsanto because the company had gotten itself into serious trouble at the time. In the early 1980s, Monsanto was facing hundreds of millions, possibly billions, of dollars in lawsuits by tens of thousands of Vietnam veterans, and by former Monsanto workers, all claiming they had been harmed by exposure to Agent Orange, or to the dioxin that it contains. If all such claims had been sustained in court, it seems likely that Monsanto would have been bankrupted.
Bill Gaffey admitted under oath that he knew he had been hired in 1979 partly to help defend Monsanto against lawsuits over dioxin. Gaffey [was] a mathematician who retired in 1989 as director of epidemiology for Monsanto and died of a heart attack on Oct 6 1995.
Gaffey’s work was also important to the federal government. The Veterans Administration relied in part on Gaffey’s work to deny medical benefits to tens of thousands of Vietnam veterans exposed to Agent Orange. (Not until 1992 did the VA reverse its position on this.) U.S. Environmental Protection Agency (EPA) relied in part on the Gaffey study to set generous limits on dioxin exposures for the American public, thus providing minimal regulation for politically powerful industries such as paper, oil, and chemicals.
EPA now acknowledges that dioxin is a devilishly potent growth dysregulator and ‘environmental hormone,’ but in large measure the agency still regulates dioxin by rules set during the era of Bill Gaffey’s work.
During a worker lawsuit against Monsanto in 1984, plaintiffs’ lawyers discovered that Gaffey and [Judith] Zack had classified four workers as ‘unexposed’ to dioxin when the very same four workers had been classified as ‘exposed’ to dioxin in a previous Monsanto study co-authored by Zack. Reluctantly, Zack confirmed this fact under oath. Thus was it discovered that Gaffey’s data had been cooked.
When an official of U.S. Environmental Protection Agency (EPA), Cate Jenkins, learned of this in 1990, she immediately sent a memo to her superiors, attaching a portion of a legal brief about the Gaffey study (and other studies sponsored by Monsanto), indicating she believed there was evidence of fraud.
1981: An electrical capacitor fire in Binghampton, New York, contaminates state office building with PCBs and PCDFs.
1981 A Review Panel on Agent Orange is established through the Office of Technology Assessment (OTA) by the US Congress.
1981 June 15: New York State Governor to sign a bill which
"Authorizes actions to recover damages for personal injury caused by exposure to Agent Orange for veterans who served in Viet Nam between January 1, 1962 and March 29, 1973. "[6]
1981 Aug 22: A National Journal article on the Graying of the VA (Veteran's Administration) -- and the possibility that some veterans will be denied health care. They expect to be swamped when the vets turn 65 and automatically become eligable for free health care. Some will be those
Vietnam War veterans who may medical problems stemming from exposre to Agent Orange, a controversial defoliant widely used in the Southeast Asian conflict. [7]
This causes Dow to begin phasing out challenges to EPA restrictions on the agricultural use of 2,4,5-T, and concentrate their efforts on defending against Agent Orange cases and the constant demands for clean-ups of dioxins from the country surrounding their Michigan plant. They hired PR firm Hill & Knowlton (previously the advisor to the tobacco industry) and launched a massive media campaign.
1982–87: US Centers for Disease Control begins to study Agent Orange and Vietnam veterans health effects.
1982 The Reagan Administration's political appointee, Rita Lavelle, now the EPA's Assistant Administrator for Solid Wastes and Emergency Response, was in charge of the Superfund Office. She established the levels of contamination that would qualify for clean-up action under the Superfund program. Her Scientific Advisory Board (with heavy industry input) advised her to set the levels high to "buy time" until the EPA risk assessment forced it lower.
1982 Nov Times Beach crisis begins. This was a cheap weekend holiday-home area for St Louis residents. A reporter had been leaked a Superfund document which listed suspected dioxin sites across Missouri and Times Beach was at the top of the list. Chemical waste from a nearby plant at Verona, had been mixed with used motor oil by a haulage contractor, Russell Bliss, then sold to farms and towns as a dust suppressant.
Both the town council and the EPA decided to test for dioxins. But on December 5 the area became flooded with the entire town submerged. The town's test results arrived just as the they began to be rebuilt: the soils were loaded with both PCBs and dioxins. The later EPA report confirmed that dioxins were 100-times the hazardous level. The residents petitioned President Ronald Reagan asking for a buyout under the Superfund scheme.
1983 Jan-Feb Reagan's "Times Beach Dioxin Task Force" worked with the WhiteHouse and had representatives from the EPA, CDC, FEMA (Federal Emergency Management Agency) and the Army Corps of Engineers (Tozzi's old outfit). The Task Force under Anne Gorsuch Burford (the do-nothing administrator of the EPA) finally announced that the government would buy-out 800 residential properties at Times Beach for $36.7 million. The general public now had clear evidence of what happens with lax chemical regulation.
A month later Burford resigned over allegations of mismanagement of the Superfund program. Her Deputy Rita Lavelle was also forced out over misleading Congress.
The EPA halts production of 2,4,5-T and the first Agent Orange class action begins.
1983–85: General industrialised populations found to be contaminated with PCDFs and PCDDs.
1983:After a fierce battle between residents over whether the dioxin levels justified abandoning the town, the majority decided on evacuation of Times Beach, Missouri, USA. They then had prolonged negotiations over the prices to be paid from the Superfund
1983 Dec 19 Report that Judge Weinstein certifies class of claimants. It seems as if he has instructed those supporting the injured vets to create a single class action available to all US, New Zealand and Australian members of the Armed Forces in Vietnam between 1961 and 1972. They are automatically in this class action, unless they opt out - and if they do opt out they retain their rights to a share in any punitive damages.
He was also considering reinstating the US Government as a defendant (they had been dismissd earlier by a US Circuit Judge George Pratt) [8]
1984: Judge forces $180m settlement in Agent Orange action.
1984 May [From March 10 1985 New York Times article. It reports on radiation hazard litigation:
Thousands of similar atomic radiation claims are pending.
In a somewhat similar case, seven manufacturers of Agent Orange agreed last May to pay $180 million to settle a class action by Vietnam veterans allegedly harmed by the defoliant. Some 200,000 claims have been filed for a share of the fund.
Later, Federal District Judge Jack B. Weinstein, of Manhattan, who had pushed for a settlement, questioned whether the case should have been brought at all.
He said no factual coniiection of any substance had been shown between the diseases and Agent Orange. Now he is weighing a proposed plan to distribute the money without requiring the claimants to prove Agent Orange caused their maladies. [9]
1985: USEPA assessment of TCDD.
1985–88: Kemner–Monsanto trial.
1986: Chlorine-bleached paper mills found to produce dioxin.
1988: First USEPA reassessment of dioxin.
1989: Study of Seveso population reveals high levels of soft tissue sarcoma.
1989–90: Monsanto’s manipulation of health studies revealed in court.
1990: Monsanto’s flawed studies publicly exposed.
1990 Aug The EPA, US Surgeon Genera,l and the Centers for Disease Control jointly announced that new scientific data indicated a lower level of risk should be assigned to dioxins than had been used in 1983 with Times Beach (characterised as the most dangerous known human toxin)
1991: US (Fingerhut) cancer mortality study of 5,172 workers in twelve trichlorophenol factories reveals elevated cancer levels and high incidence of soft tissue sarcoma.
1991: German (Manz) cancer mortality study of 1,583 workers reveals elevated cancer levels among long-term employed and high levels of breast cancer among women.
1991: Second USEPA reassessment of dioxin begins.
1991: Scientists announce link between hormone-disrupting chemicals and falling sperm counts in human males.
1991: Second Agent Orange class action begins.
1992: (North American) Great Lakes Commission calls for ban on persistent toxic substances ‘whether or not unassailable scientific proof of acute or chronic damage is universally accepted.
1993: American Public Health Association calls for a ‘gradual phase-out’ of most organochlorines, to be replaced by safer alternatives.
1993-4 The chemical industry began a $5 million public relations campaign with the release of a 1994 report entitled "Scientific Principles for Evaluating the Potential for Adverse Effects from Chlorinated Organic Chemicals in the Environment" written for the Chlorine Institute by the
Canadian consulting firm CanTox. [A tobacco and EMF science-for-sale operation run by lobbyist Ian Munro.]
It argues that concerns about organochlorines must be addressed within the current regulatory framework. According to CanTox, since organochlorines vary in their chemical and biological behavior, they must be addressed only on a chemical-by-chemical basis.
Risk assessments must be performed for each chemical; these assessments must then determine the appropriate pollution control and disposal methods to "ensure that environmental release rates of specific chemicals are maintained below those that would result in adverse effects."
Evidence of large scale damage to human health and the environment should be considered valid only when scientists can prove "the specificity of the associations between specific chlorinated organic chemicals and reported adverse effects."
1994: USEPA release 2,400-page draft report on dioxins.
1997: International Agency for Cancer Research (IARC) declare dioxin a human carcinogen.
1997: International cancer mortality study of 21,863 workers exposed to phenoxy herbicides, chlorophenols and dioxins in twelve countries reveals a slight general cancer risk and a high risk to specific cancers, significantly soft tissue sarcoma.
1998: 30 years after the war with the USA, Vietnamese people still exposed to dioxin via their food chain. ‘Concentrations of dioxin applied during the Vietnam war era persist in the Vietnamese environment today. Persistent dioxin contamination is present, and is suspected to be related to medical problems being experienced by some Vietnamese born after the war,’ Hatfield, Canadian consultants, state in their report. ‘Dioxin concentrations in Agent Orange were in the range of a billion times more than that found in some Canadian industrial effluent’.
1998: A $200 million US Air Force study on the effects of Agent Orange on exposed military was tampered with. Scientists, who drafted two reports, withheld information on high rates of birth defects and infant deaths among children of Vietnam vets in the first report and altered the second report to give the impression that vets’ cancers were not unusual. The data from the first report was finally released in 1992.
1999: 500 tons of animal feed contaminated with approximately 50kg of PCBs and 1g of dioxins distributed to animal farms in Belgium, the Netherlands, France, and Germany.
2000: Scientists from the USA and Vietnam meet in Singapore to explore the possibility of launching a joint research programme to study the human and environmental health effects resulting from spraying Agent Orange and other herbicides during the Vietnam War.
2003: US court allows Vietnam veterans to sue Agent Orange manufacturers.
2004: Vietnamese workers file civil action in US courts against manufacturers of Agent Orange.
