Healthy-Again, Your Path To Health and Recovery

Natural Non-Drug Cures - Therapies - Treatments - Remedies for Cancer, Heart Disease, AIDS, and other Chronic Illness


Let thy food be thy medicine, and thy medicine be thy food.
Hippocrates, Father of Medicine, 400 B.C.

Jonathan Campbell

Helping people take charge of their health

 


Introduction
Covid-19 Protection and Treatment
Covid-19 Supplement Protocol
Long Covid Treatment/Cure
Natural Therapies
How to Prevent/Stop Influenza
Natural Cancer Therapy
Natural Cardiovascular Disease Therapy
Natural Cholesterol Control Therapy
Natural Statin Injury Therapy
Type II Diabetes
What Is AIDS?
Natural AIDS Therapy
Natural Chronic Fatigue Therapy
Natural Hepatitis C Therapy
Natural Mental Disorders Therapy
Natural Sexual Dysfunction Therapy
Patient Empowerment
Menopause Naturally
Poverty In America
About Jonathan Campbell
Home Page

 

The 1994 EPA Dioxin Reassessment

Health Assessment, Volume III: Risk Characaterization

9.2. CHEMICAL STRUCTURE AND PROPERTIES

Polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) are chemically classified as halogenated aromatic hydrocarbons. The chlorinated and brominated dibenzodioxins and dibenzofurans are tricyclic aromatic compounds with similar physical and chemical properties, and both classes are similar structurally. Certain of the PCBs (the so-called coplanar or mono-ortho coplanar congeners) are also structurally and conformationally similar. The most widely studied of these compounds is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). This compound, often called simply dioxin, represents the reference compound for this class of compounds. The structure of TCDD and several related compounds is shown in Figure 9-1.

For purposes of this document, dioxin-like compounds are defined to include the subset of this class of compounds, which are generally agreed to produce dioxin-like toxicity. These compounds are assigned individual toxicity equivalence factor (TEF) values as defined by international convention (U.S. EPA, 1989). Results of in vitro and in vivo laboratory studies contribute to the assignment of a relative toxicity value. TEFs are estimates of the toxicity of dioxin-like compounds relative to the toxicity of TCDD, which is assigned a TEF of 1.0. All chlorinated dibenzodioxins (CDDs) and chlorinated dibenzofurans (CDFs) with chlorines substituted in the 2,3,7, and 8 positions are assigned TEF values. Additionally, the analogous brominated dioxins and furans (BDDs and BDFs) and certain polychlorinated biphenyls have recently been identified as having dioxin-like toxicity and thus are also included in the definition of dioxin-like compounds. Generally accepted TEF values for chlorinated dibenzodioxins and dibenzofurans are shown in Table 9-1 A recent World Health Organization/International Program on Chemical Safety meeting held in The Netherlands in December 1993 considered the need to derive internationally acceptable interim TEFs for the dioxin-like PCBs. Recommendations arising from that meeting of experts (Ahlborg et al., 1994) suggest that in general only a few of the dioxin-like PCBs are likely to be significant contributors to general population exposures to dioxin-like

 

 

compounds. Dioxin-like PCBs may be responsible for approximately one-fourth to one-half of the total toxicity equivalence associated with general population environmental exposures to this class of related compounds. Both the refinement of the toxicity equivalence factors for dioxin-like PCB congeners (DeVito et al., 1993) as well as a compilation and analysis of all available data on relative toxicities of dioxin-like PCBs with respect to a number of end points (Ahlborg et al., 1994) support these findings. Although these findings have been published recently, additional review and data collection will be needed. In addition, this panel urged investigation of companion TEFs for ecotoxicological use, based on data from ecotoxicological studies.

Throughout this document, concentrations of dioxin and related compounds will be presented as TEQs. TEQs are determined by summing the products of multiplying concentrations of individual dioxin-like compounds times the corresponding TEF for that compound. At times, levels will be presented as concentrations of TCDD because many past studies monitored this congener alone. At most times, TEQs for CDDs and CDFs will be discussed. When TEQ values include the dioxin-like PCBs as well, this will be specifically mentioned. Readers of this chapter are encouraged to review previous chapters in the Health Assessment Document and the Exposure Document for more details on estimates of TEQ presented in this chapter. The strengths and weaknesses as well as the uncertainties associated with the TEF/TEQ approach are discussed later in this chapter.

There are 75 individual compounds comprising the CDDs, depending on the positioning of the chlorine(s), and 135 different CDFs. These are called individual congeners. Likewise, there are 75 different positional congeners of BDDs and 135 different congeners of BDFs (see Exposure Document, Table 2-1). Only 7 of the 75 congeners of CDDs or of BDDs are thought to have dioxin-like toxicity; these are ones with chlorine/bromine substitutions in, at least, the 2, 3, 7, and 8 positions. Only 10 of the 135 possible congeners of CDFs or of BDFs are thought to have dioxin-like toxicity; these also are ones with substitutions in the 2, 3, 7, and 8 positions. While this suggests 34 individual CDDs, CDFs, BDDs, or BDFs with dioxin-like toxicity, inclusion of the mixed chloro/bromo congeners substantially increases the number of possible congeners with dioxin-like activity. There are 209 PCB congeners. Only 13 of the 209 congeners are thought to have dioxin-like toxicity; these are PCBs with 4 or more chlorines with just 1 or no substitution in the ortho position. These compounds are sometimes referred to as coplanar, meaning that they can assume a flat configuration with rings in the same plane. Similarly configured polybrominated biphenyls are likely to have similar properties; however, the data base on these compounds with regard to dioxin-like activity has been less extensively evaluated. Mixed chlorinated and brominated congeners also exist, increasing the number of compounds considered dioxin-like. The physical/chemical properties of each congener vary according to the degree and position of chlorine and/or bromine substitution. Very little is known about occurrence and toxicity of the mixed (chlorinated and brominated) dioxin, furan, and biphenyl congeners.

In general, these compounds have very low water solubility, high octanol-water partition coefficients, and low vapor pressure and tend to bioaccumulate. Volume II of the Exposure Document presents congener-specific values for water solubility, vapor pressure, partition coefficients, and photo quantum yields and discusses other physicochemical characteristics of the chlorinated dioxins and dibenzofurans. These physicochemical properties result in the environmental fate and transport discussed below. Expanded discussions will be required in future documents to account for dioxin-like PCBs and for brominated or mixed halogenated congeners.

Continue to 9.3



Payment/Donation Request

If you find that the information on this site has provided you  with useful health information, or you would like to contribute to help the cause of providing this kind of service to people, please consider a modest payment for these information services.

I use my Healthy-Again PayPal account for the payment button, and you can use your PayPal account or any credit or debit card for payment. I have programmed the button to be a payment for information services, so you will not be charged any extra transaction fees. Select the amount you would like to pay. Any amount will be gratefully received.

If you don't have a PayPal account, PayPal will allow you to use any credit or debit card. PayPal is a completely safe, data secure funds transfer and payment service. Look for the lock symbol next to the PayPal URL (https://www.paypal.com), which guarantees that your payment is secure and encrypted.

Payment Options

Natural Therapy Home Page

Download A Natural Therapy Guide

©Graphics, Web design, and content Copyright 2003-2024 by Jonathan L. Campbell.
HealthyAgain and HealthyHomes are trademarks of Jonathan L. Campbell of Massachusetts, as of June 1, 2010
 

Healthy-Again, Your Path To Health and Recovery
124 Metropolitan Ave.
Roslindale, MA 02131-4208

https://www.healthy-again.net


Could Vitamin C stop the Ebola epidemic?

Diabetes, Pre-diabetes, and Severe Hypoglycemia are 100% corellated to Cardiovascular Disease

All health guides are now free for download

Now Available For Free Download: The Looting of Social Security by economist Alan Smith, http://www.thebiglie.net

Japan Nuclear Emergency and Worldwide Fallout - What To Do? http://www.healthy-again.net/japannuclearemergency.htm

Has your doctor prescribed Lipitor or another statin drug? Just say no! http://www.healthy-again.net/lipitor.htm

You don't need to take statin drugs...please don't take them! http://www.healthy-again.net/lipitor.htm

Muscle aches, weakness, numbness, brain fog - have you been harmed by Lipitor? http://www.healthy-again.net/lipitor.htm

Can 40 million people be wrong on Lipitor? Yes they can! http://www.healthy-again.net/wrongonlipitor.htm

Lipitor may ruin your health! http://www.healthy-again.net/lipitor.htm

Read about Lipitor side effects - http://www.healthy-again.net/lipitor.htm

If you are seeking a natural therapy, treatment, remedy, or cure for cancer, heart disease, AIDS, or other chronic illness: go to http://www.healthy-again.net

Swine Flu Vaccine Causes Miscarriage: http://www.healthy-again.net/swinefluvaccine.htm

Effective Natural Treatment for cancer: http://www.healthy-again.net/cancertherapy.htm

Cure - Reverse - Heart Disease: http://www.healthy-again.net

Effective Natural Treatment for heart disease: http://www.healthy-again.net/cvd.htm

Effective Natural Treatment for hepatitis: http://www.healthy-again.net/hepatitis.htm

30-60 Million People Are Being Harmed By Statin Drugs. Are You One Of Them? http://www.healthy-again.net/lipitor.htm

Miracle Mineral Supplement (MMS) Is A Toxic Fraud - Please Don't Take It! http://www.healthy-again.net/mms.htm

Colloidal Silver is Toxic - Don't Take It! http://www.healthy-again.net/silver.htm

Alternative "treatments" and "cures" to avoid:
Protocel (also called Cancell, Cantron, Sheridan's Formula)
Poly-MVA
Infrared sauna (especially far infrared, which actually causes cancer)
Cesium therapy
Miracle Mineral Supplement (MMS)
Zeolite liquid (NCD)
Essiac Tea
Alkaline pH
Coral Calcium
Colloidal Silver
Any treatment that specifies not to take Vitamin C
Fasting
"Fruit-only" regimens

http://www.healthy-again.net/therapiestoavoid.htm

Thinking about getting an HIV Test? Don't! http://www.healthy-again.net/aidtests.htm

Sudden Infant Death Syndrome (SIDS) Can Be Avoided! http://www.healthy-again.net/sids.htm

What's Wrong With Dricore: http://www.healthy-again.net/homeqa/dricore.htm

Reliable Concrete Cutting Massachusetts: http://www.healthy-again.net/homeqa/bcd.htm

Looting Social Security - How Reagan and Greenspan Stole the Trust Fund: http://www.thebiglie.net

How to Buy Siliver and Gold - An Economic and Health Survival Guide - Navigating Through Economic Turmoil: http://www.healthy-again.net/community-alert/survivalguides.htm

Bauman Remodeling of Dedham, a review: http://www.healthy-again.net/homeqa/contractorfrom.htm

Stop Spam - Subscribe to SpamCop - http://www.spamcop.net

Reduce The Burden of the HIV and AIDS diagnosis - http://www.reducetheburden.org

Quitting AIDS drugs is hard to do - http://www.healthy-again.net/quittingaidsdrugs.htm

Danger - Never Get An HIV Test - Ever! http://www.healthy-again.net/aidstests.htm

What Is AIDS? http://www.healthy-again.net/aids.htm

Conventional Medicine Does Not Provide Answers - http://www.healthy-again.net/conventionalmedicine.htm

Healthy-Again Computers - Buying And Maintaining Computer Equipment

Why My HP Printer Stopped Working - HP's Business Model

How To Avoid The HP "Firmware Update"

HP Printer Firmware Downgrade Links