The Biological significance of dioxins and other organochlorines papers and proceedings from a symposium : Centre for Pharmacology, Medicinal Chemistry and Toxicology, University of Tasmania, Hobart, November 13, 1991

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Published by The University in [Hobart .

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  • Dioxins -- Environmental aspects -- Congresses.,
  • Dioxins -- Toxicology -- Congresses.,
  • Organochlorine compounds -- Environmental aspects -- Congresses.,
  • Organochlorine compounds -- Toxicology -- Congresses.,
  • Pesticides -- Environmental aspects -- Congresses.,
  • Pesticides -- Toxicology -- Congresses.

Edition Notes

Includes bibliographies.

Book details

StatementS.R. McLean, R.M. Lowenthal (eds.).
ContributionsLowenthal, R. M., McLean, S. R., University of Tasmania. Centre for Pharmacology, Medicinal Chemistry and Toxicology.
LC ClassificationsQH545.O72 B56 1992
The Physical Object
Paginationvii, 121 p. :
Number of Pages121
ID Numbers
Open LibraryOL18671811M
ISBN 100859015114

Download The Biological significance of dioxins and other organochlorines

1. Med J Aust. Jan 20;(2) The biological significance of dioxins and other organochlorines. McLean S. PMID: [Indexed for MEDLINE]Author: Stuart McLean.

Polychlorinated dibenzo-p-dioxin (PCDDs) and polychlorinated dibenzofurans (PCDFs) are highly toxic, the most dangerous being 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

Testing study on toxicity of the TCDD is used as a mechanism and reference value for other dioxins [9, 10, 11]. PCDD/Fs and PCB dioxin-like were verified in different Author: Aurel Nuro. The dangers of organochlorines and a proposed solution. Pandora's Poison presents a solution to one of the most insidious environmental problems of our time: the global build-up of toxic chemicals.

Everywhere on the planet, hundreds of industrial chemicals called organochlorines are accumulating in the environment, the food supply, and our bodies. Concentrations of dioxins and other organochlorines (PCBs, DDTs, HCHs) in human milk from Seveso, Milan and a Lombardian rural area in Italy: A study performed 25 years after the heavy dioxin.

Dioxins, which are highly toxic, are created by any kind of burning process. This burning includes some industrial processes, burning of waste, and fires at landfills, backyards and in forests.

The burning of coal and wood and to a lesser extent the combustion of petrol and diesel in motor vehicles are also a source of dioxins. TCDD is the most potent synthetic toxin, second only to venoms, that is, biospherical toxins. Dibenzo-p-dioxin and dibenzofuran can also be substituted with other halogens, that is, fluorine, bromine and iodine.

As a result, there are 75 dioxin congeners and dibenzofuran congeners (Schiavon et. Five organochlorines (polychlorinated biphenyl congener no. a-chlordane, y-chlordane, cis-nonachlor, and aldrin) were detected in other organochlorines were found in % of all participating women (Table 2).

Akovali, in Toxicity of Building Materials, Health and safety concerns related to the inherent chemistry of PVC. PVC is an organochlorine chemical (which is a carbon-based organic chemical with one or more chlorine atoms), which exhibits a number of important attributes shared by the class.

Over three-quarters of about 40 million tons of chlorine produced annually is used in the. The health effects of dioxins have long been a contentious issue.

The Ministry's involvement in dioxins is the health effects in the population, and whether adequate health care is available to those who may be suffering from the effects of dioxins exposure. A basic finding is that many xenochemicals such as PAHs, as well as dioxins, dioxin-like PCBs, and other organochlorines act through a common ubiquitous molecular pathway involving the arylhydrocarbon receptor (AhR).

AhR is a ligand-activated transcription factor known to mediate the pleiotropic effects of many environmental pollutants.

Biological Effects of PCBs Review the discussion on organochlorine pesticides and plants from Chapter 5 because similar relationships pertain to PCBs and plants. Generally speaking, PCBs are not thought to be toxic to plants because the more toxic, highly chlorinated PCBs including those that have dioxin-like properties are not absorbed very.

Another chemical class known as polychlorinated dibenzodioxins (PCDDs),or dioxins, are also classified as organochlorines. Tree frogs have an organochlorine alkaloid in their skin. With rare exceptions, organochlorine substances do not occur naturally in isolation, but are found in biological hosts like bacteria and various marine organisms.

Organochlorines are ubiquitously present as a mixture of mother compounds and metabolites in the environment and are characterized by high lipid solubility, environmental persistence, bioaccumulation (Agency for Toxic Substances and Disease Registry ), and long biological half-lives in human tissue (Wolff et al.

The significance of the strongest dynamic associations, among those identified by PCA and co-inertia analysis, involving clinical-biological parameters and POP contamination levels, was further evaluated by building linear mixed-effects (LME) models to test for intervariable redundancies and to adjust for potential confounding factors.

An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalently bonded atom of chlorine that has an effect on the chemical behavior of the chloroalkane class (alkanes with one or more hydrogens substituted by chlorine) provides common examples.

The wide structural variety and divergent chemical. Furthermore, as these chemicals are relatively volatile, of low molecular weight, and readily degraded by natural physical, chemical, and biological processes, they do not meet the criteria to be considered persistent or bioaccumulative.

All organochlorines are equally "bad" in a toxicological sense and all should be banned. Other countries have replaced organochlorines with the less persistent and more effective organophosphorus compounds. Pyrethrins and Pyrethroids are non-persistent pesticides used worldwide as insecticides in agriculture, forestry, households, public health and stored products [ ].

Organochlorines are extremely stable, sometimes taking hundreds of years to break down. When dioxin is taken into the cell nucleus, it works like a "turn on" valve which begins the production of enzymes.

Enzymes cause a vast amount of bodily activity. The huge number of enzymes do two things: start and stop biological activity. Of these other classes of organochlorines, there was the most evidence of an association between dioxins and non-Hodgkin's lymphoma.

The most potent dioxin congener, 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD), has been declared a human carcinogen by the IARC for all cancer sites based on sufficient evidence in animals, a convincing.

@article{osti_, title = {Chemical carcinogens. Second edition}, author = {Searle, C E}, abstractNote = {This book looks at the latest research in chemical carcinogenic agents. To gain an understanding these agents and their importance in identifying the occupational and environmental causes of cancer.

Amon organic pollutants 2,3,7,8-TCDD is one of the most potent carcinogenic chemical, able to elicit a wide spectrum of biological effects following specific cellular pathways (Mandal, ;White.

Agonists of CAR/PXR group include the environmentally persistent non-coplanar PCBs and other non-planar organochlorines (Kopec et al., ) and can play a critical role in the disposition and toxicity of environmental chemicals, primarily by altering their metabolism to less toxic or more toxic metabolites (Stanley et al., ).

Keynote Address at the Second Citizens Conference on Dioxin, St. Louis, Missouri, J The Political History of Dioxin.

by Barry Commoner, Center for the Biology of Natural Systems. Note: The term 'dioxin' is used to connote the group of similar substances—polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans. Certain types of polychlorbiphenyls (PCBs) have.

In fact, these and other organochlorines are part of a group of “persistent organic pollutants” (POPs) that are being phased out globally in accordance with the United Nations‐sponsored Stockholm Convention, signed on 54 The driving concerns for this phaseout are ecosystem effects, effects on nonhuman species, and human.

Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and p,p′-diphenyldichloroethene (DDE) are widespread persistent environmental gh human body burdens of these chemicals have been decreasing over time (Hagmar et al.

; Schecter et al. ), they remain detectable in most of the. Alternatives to Organochlorines. Finding effective alternatives to pesticides—organochlorines, in particular—is a major global challenge.

Much of modern agriculture depends on pesticide use for reliable crop production, and officials struggle to contain public threats such as malaria without the use of organochlorines such as DDT.

In the exposure analysis, tri- to penta-chlorinated CB, CB and CB, with no dioxin-like biological activity, were grouped together (CB 28+52+) because serum levels of these compounds showed low correlations with serum levels of the other organochlorine compounds (Spearman's r =.

Second, workers who work with organochlorines might also be exposed to other potential chemicals, such as dioxin, which was not measured in our study. In a meta-analysis (Van Maele-Fabry et al. ), workers engaged in manufacturing of phenoxy herbicides contaminated with dioxins and furans were shown to have an increased risk of prostate cancer.

PCB levels are often monitored because they could also reflect exposure to several other chemical contaminants such as other organochlorines. Other highly toxic compounds such as polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were found in the blubber from arctic ringed seals caught near the west coast of Spitzbergen.

Biological mechanisms of dioxin action. [Cold Spring Harbor, N.Y.]: Cold Spring Harbor Laboratory, (OCoLC) Material Type: Conference publication: Document Type: Book: All Authors / Contributors: Alan Poland; Renate D Kimbrough. Defunctionalization of organochlorines through reductive dechlorination (also known as hydrodechlorination—replacement of chlorine atoms by hydrogen—is one of the main methodologies used in the detoxification of these harmful compounds.

Most of the published papers on this particular matter focused on specific reagents, reaction conditions, and mainly result efficiency. Barry Commoner's keynote address at the Second Citizen's Conference on Dioxin (St.

Louis, July ) Generations: Reproductive & Developmental Effects of Organochlorines Eric Weltman summarizes new evidence on the biological dangers of these chemicals.

Dioxin's Toll on Wildlife Vicki Monks describes the effects of dioxins on Great Lakes birds. A reduction in birth weight and other measures of size was observed for dioxin-like PCBs, but these results were not statistically significant.

A study by Van Tung et al. () of residents of a dioxin hot spot area in Vietnam 4 reported on 58 mother–infant pairs who were compared with 62 pairs from a region thought to be uncontaminated.

Vinyl is a major dioxin source. Vinyl is the predominant chlorine donor and therefore a major and preventable cause of dioxin forma-tion in most of the leading dioxin sources that have been identified.

When its entire lifecycle is considered, vinyl appears to be associated with more dioxin formation than any other single product. Agent Orange, an herbicide used by the United States during the Vietnam War, contained dioxins (most importantly, 2,3,7,8-tetrachlorodibenzo-p-dioxin [TCDD], the most toxic and extensively researched dioxin) as contaminants.

Some PCBs have biological activity similar to that of dioxins and are identified as “dioxin. Dioxins are called persistent organic pollutants (POPs), meaning they take a long time to break down once they are in the environment.

Dioxins are highly toxic and can cause cancer, reproductive and developmental problems, damage to the immune system, and can interfere with hormones. Explores the latest science on dioxins and other POPs, and their impact on human health. Now in its third edition, Dioxins and Health is the most respected reference of its kind, presenting the latest scientific findings on dioxins, dibenzofurans, polychlorinated biphenyls and related compounds, and their impact on human health.

The book fully examines the many toxicological effects Reviews: 3. Thornton gives the graph of dioxin deposition to the Great Lakes sediment (page ), but stops inso that there is a good correlation with chlorine production. But he omits the data which show that with steady chlorine production (and a tripled PVC production), dioxin deposition has fallen dramatically back to the pre levels.

No significant feature was observed in the other targeted chemical families (dioxins, ndl-PCB, OCPs, BFRs and PFAS). Further biological investigations are required ex vivo to determine if this discrete but recurrent signature could be associated with the etiology and pathogenesis of breast cancer subtypes, or appears as a marker without a role.

Coplanar PCBs in human milk in the province of Quebec, Canada: Are they more toxic than dioxin for breast fed infants. The researchers tested whether cytokine production by immune cells collected from cord blood was impaired in newborns that had been exposed to PCBs and other organochlorines in utero.

As expected, mean concentrations of p,p'-DDE, HCB, and PCBs were significantly higher in the subsistence fishing group than in the reference group. The effects of organochlorines on thyroid hormone homeostasis have been studied in humans, but results have not been consistent.

Most investigations of endocrine disruption by PCBs, PCDDs, PCDFs, and DDE in humans have focused on populations with higher exposures due to occupation or residence near areas contaminated by industry (Calvert et al.

; Langer et al.and related organochlorines (e.g. chlordane, aldrin, dieldrin, endrin and mirex) saw increasing use as agricultural insecticides. However, growing concerns over environmental impacts culminated in the pub- lication of Rachel Carson's landmark book Silent Spring inwhich led to a large public outcry and an eventual ban on DDT for agricul.

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