DIOXIN

The DIOXIN Conference is a online bulletin board for scientists to exchange information on dioxins and related compounds. Free registration is required. Maintained by the Department of Hygiene, Social- and Environmental Medicine of the Ruhr-University Bochum, Germany, the site is in English. The conference has 18 forums: 12 for general aspects of dioxins; analytical methods, ecotoxicology, emission control, environmental levels, epidemiology, formation and sources, human exposure, human levels, quality control, risk assessment and management, toxicology , and transport and fate; five for related compounds; endocrine disrupters, polyhalogenated biphenyls, short chain aliphatic halocarbons, toxaphenes, other halogenated compounds; and one for announcements.

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5/2000:

REASONABLY ANTICIPATED TO BE A HUMAN CARCINOGEN NINTH REPORT ON CARCINOGENS

2,3,7,8-TETRACHORODIBENZO-p-DIOXIN (TCDD); DIOXIN *

CAS No. 1746-01-6

First Listed in the Second Annual Report on Carcinogens

CARCINOGENICITY 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (2 3 7 8-TCDD or TCDD) is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals (IARC V.5 1977; NTP 201 1982; NTP 209 1982; IARC S.4 1982; IARC S.7 1987). When administered by gavage TCDD increased the incidences of thyroid follicular cell adenomas in male rats and neoplastic nodules of the liver in female rats. When administered by the same route TCDD increased the incidences of hepatocellular carcinomas in mice of both sexes and thyroid follicular cell adenomas in female mice. When administered in the diet the compound induced hepatocellular carcinomas and squamous cell carcinomas of the lung and hard palate nasal turbinates in female rats. It also induced squamous cell carcinomas of the tongue and hard palate nasal turbinates in male rats (Kociba et al. 1978a; idem. 1978b). When administered topically TCDD induced fibrosarcomas of the integumentary system of female mice. When administered by intraperitoneal injection TCDD induced thymic lymphomas and liver tumors in infant mice. In a two-stage skin carcinogenesis study TCDD was a weak tumor initiator in mice when applied topically before application of 12-O-tetradecanoylphorbol-13-acetate. TCDD was also effective as a promoter increasing the incidences of hepatocellular carcinomas in rats treated subcutaneously with TCDD and intragastrically with N-nitrosodiethylamine. An IARC Working Group reported that there are no adequate data to evaluate the carcinogenicity of 2 3 7 8-tetrachlorodibenzo-p-dioxin in humans (IARC S.7 1987). .....

Searched for 2,3,7,8-TCDD at: http://www.niehs.nih.gov/external/search.htm

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3) Environmental Health Perspectives, Volume 106, Supplement 2, April 1998

PCDD/PCDF Indoor Exposure in Day-Care Centers and PCDD/PCDF Blood
Concentrations of Female Employees
Sabine von Manikowsky,1 Helmut Sagunski,1 Olaf Päpke,2 Karl-Rainer
Fabig,3 Hermann Neus,1 Michael Schümann,1
Karen Spannhake,1 Wilfried Karmaus,4 Nadia Osius,4 and Bernd Zier2

1 Hamburg State Department of Labor, Health and Social Affairs, Hamburg,
Germany; 2 ERGO-Forschungsgesellschaft mbH,
Hamburg, Germany; 3 Practice Fabig, Hamburg, Germany; 4 NORDIG,
Institute for Health Research and Prevention, Hamburg, Germany

Abstract

We determined blood concentrations of polychlorinated dibenzo-p-dioxins
(PCDDs) and polychlorinated dibenzofurans (PCDFs) in
41 female employees with previous exposure to pentachlorophenol-based
wood preservatives from 10 day-care centers in the
Hamburg, Germany, area. We compared the blood concentrations with
estimated age-dependent reference values and analyzed the correlation between PCDD/PCDF indoor air exposure and blood concentrations............................

Environ Health Perspect 106(Suppl 2):707-714 (1998).
Dioxins and Furans: Epidemiologic Assessment of Cancer Risks and Other
Human Health Effects

http://ehpnet1.niehs.nih.gov/docs/1998/Suppl-2/707-714manikowsky/abstract.html

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June/2000:

''Dioxin, a highly toxic environmental pollutant, is a byproduct of the manufacturing processes for paper, chemicals, paint, steel and pesticides. A member of the same group of compounds as PCBs known as halogenated aromatic hydrocarbons, dioxin has been shown to be extremely resistant to biological and chemical cleanup processes. ''

source:

http://www.enn.com/

For more about dioxin and dioxin-related compounds, visit the EPA's Dioxin and Related Compounds information page. http://www.epa.gov/ncea/dioxin.htm

EPA also has a lot of information on their web site about their dioxin toxicity reassessment process.

http://www.epa.gov/ncea/pdfs/dioxin/dioxreass.htm

The U.S. Federal Register account of the release of the documents has details about the review process.

http://www.epa.gov/fedrgstr/EPA-SAB/2000/June/Day-12/sab14853.htm

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10/04/00 - Scientists track dioxin from U.S. smokestacks to remote Arctic villages

NEW YORK (AP) -- For the first time, scientists say they have pinpointed many of the industrial polluters responsible for the dioxin that is ending up in the Arctic. http://www.cnn.com/2000/NATURE/10/04/dioxin.sources.ap/

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October 4, 2000, Post Tribune..com: NWI plants toxic to world? By Dave Orrick

A study released Tuesday ranks two local steel mills among the top 10 sources of dioxin pollution in an arctic region of Northeast Canada. The study's authors pointed to it as the first time science has pinpointed the source of dioxin pollution half a continent away. To perform the study, scientists at New York City's Queens University modified a computer program originally designed to track fallout in the event of a nuclear accident.

Full story.. http://www.post-trib.com/news/index.html

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10/2000:

a summary of work by Barry Commoner et al. showing that dioxin in the Canadian arctic territory of Nunavut is mostly from a relatively limited number of sources in the United States. Their results suggests that a focused effort on these sources could reduce exposures dramatically. Citing one example (Coral Harbour, Nunavut), they observe that "total exposure to dioxin could be reduced by 35 percent if only 19 individual source--most of them in the United States--could be induced to virtually eliminate their emissions."

http://www.ourstolenfuture.org/NewScience/ubiquitous/2000commoneretal.htm