I earned a Ph.D in Chemistry in 1966. My thesis involved a new (at that time) scientific instrument, a mass spectrometer. After I graduated, I got a job with the Dow Chemical Company in the Chemical Physics Research Lab running their new high resolution mass spectrometer. I had never seen one before. It was the start of a magical career for me.

I am a living pioneer (almost 73 years old). I have done things no-one had done before. I have received the recognition of my peers in the form of publications, invitations to speak at scientific meetings in the US and Europe, and served on a committee for the Government of Canada (invited by the Minister of the Environment and the Minister of Health and Welfare) to assess the impact of dioxins in that country. I was the only US citizen on the committee.

All this was in the area of the detection and quantification of Dioxins in the environment, animals (including humans), and in chemical processes. I have developed methods (with others) to measure organic compounds at levels never before achieved at the time (water: 1-5 parts per quadrillion; human and bovine milk: 10 parts per billion; human fat: 20 parts per billion;...).

The intangible rewards have been infinitely gratifying and satisfying. The monetary compensation was enough to live comfortably (but not extravagantly). My pension and Social Security benefits allow me to enjoy my 'golden years' and still leave a legacy to my children.

Since all vehicles have both an odometer and a fuel gauge, a simple microprocessor can measure miles traveled and fuel consumed from the signals to the car's gauges. The gas tax at the gas pump can then be eliminated, and paid along with the mileage tax.

One effect of this is a reduction of gas prices. That's a damn fine sales point for the legislation.

VOTE FOR MONITORING; LOWER GAS PRICES!!!

We live South of Houston, 7 miles from the Gulf of Mexico. It is part of the culture here to be prepared to evacuate since the probability is rather high that we will be running from a hurricane [ http://goo.gl/Z9KbJ ].

The local government can require mandatory evacuation. Evacuation routes were formalized a few years ago, and supporting services are available along all the routes.

Thank you. I stand corrected.

I should have written that I discovered the site during the Bush, Jr. administration from press coverage at the time.

A search of Google Scholar yields this. The only such study I am familiar with was done at Michigan State University on the degradation of dioxins in soil. It comprises my total knowledge in this area 8^)

Dioxins are degraded by sunlight/UV. Thus the use of dioxin-containing herbicides (e.g. Agent Orange, 2,4,5-T) does not leave long-lasting dioxins on the foliage. However, any material which lands on the ground is bound to the soil. In a way this is good since the dioxins will not migrate down to the water table.

In the lab, standard solutions must be checked at least weekly since the room light slowly degrades the dioxins. It is a PIA.

Since man (and every other animal) has had dioxin in their system at very low levels during their evolution, these low levels are natural to the species. However, the ambient levels of dioxin have risen in recent time due to the activities of man, in most part due to combustion processes. No studies that I know of have addressed whether this has had a deleterious effect and if so, to what extent. Common sense, however, tells me that it probably is not a good thing.

To reduce ambient levels would require either curtailing man-made combustion, or treating all man-made combustion products before they are emitted. I don't think this is a possibility in the near future. However, the efforts to curtail global warming are a step in the right direction, IMHO.

Fortunately, plants to not take up dioxins. I was involved in an early study to determine this. We synthesized radiolabeled tetrachlorodioxin for the US Department of Agriculture for use in a study they did on uptake of dioxins in several plants. Since the analytical methods did not exist at that time to chemically determine dioxins at low levels, they could track the radioactivity to find the answer. They found that corn kernels, for example, contained no detectable dioxin. Root plants, however, had dioxin on the surface of the roots which could be washed off. My advice is to thoroughly wash root vegetables before eating.

Since animals bio-concentrate dioxins they are exposed to, limiting certain of these in the diet would be beneficial. Fish live in water which contains dioxins at very low levels. Their bodies trap a portion of them in their fatty tissues raising the level in their bodies about a factor of 3000. This takes time. Fish which are long-lived in general contain higher levels of dioxin. The US government has advisories on certain waterways against eating more than a specified number of fish per month. Also, large game fish likely have higher levels. Plant-eating animals are not exposed to equivalent levels of dioxin.

There have been several incidences of animals being contaminated with dioxins due to contaminated food. One incident mentioned in the comments above was chicken found to be contaminated with dioxin during a routine food analysis supermarket survey by the US government. The source of the contamination was due to the presence of contaminated clay which is put in the food to facilitate its ability to flow easily in the machinery which transfers it (usually via augers) from place to place during the feed's manufacture.

I was involved as a consultant to a Houston law firm in the litigation surrounding this incident. The clay contamination was of natural origin. Clay is made during the deposition of silt in lakes. It is thus stratified and can act as a 'time machine' for determining substances in the water at the time of the deposit by analyzing core samples. The deeper the sample, the older it is, and the time period can be back to prehistoric ages. The pattern of dioxins in the clay, mined from a depth of about 30 feet, was unusual. It did not match any known source.

It was found that a species of algae could manufacture dioxins. The algae were deposited, along with the silt, in a layer 30 feet below the top of the clay deposit. Since the contamination was of natural origin, and the possibility that clay could be contaminated in this way was was unknown, there was no culpable party, and the law suits evaporated. We are fortunate that our government had the foresight to monitor the food we eat for dioxin contamination.

Personally, I do not worry about dioxins in my diet. Man has evolved in the presence of dioxins and can handle the 'normal' exposure encountered in his daily life. What the government study is trying to do is to determine the level of concern for unusual exposure to dioxins. This, in turn, allows them to control the populace's exposure to dangerous levels of dioxins.

I hope this answers your questions.

If you want daily updates about dioxins try Google News

I am an analytical chemist and a pioneer in the development of analytical methods to measure dioxins at extremely low levels in a wide variety of environmental and industrial matrices from 1967 through 1994 as an employee of the Dow Chemical Company. I have published many of these seminal studies in peer-reviewed scientific journals. One of these studies was the first to establish that dioxins are formed in natural processes (such as forest fires) which produces a natural background of dioxins (at very low levels) which existed before man evolved from the apes through modern times.

As an expert in this area, I have served on an Expert Advisory Committee formed by the Canadian government to assess the impact of dioxins in that country. I was the only US citizen on the committee. The report of our findings was published by the Canadian government in 1983.

I have presented papers of my work at American Chemical Society meetings, Annual Dioxin Conference Meetings, and sat in on early meetings of toxicologists to discuss methodology and the significance of dioxin levels found in the environment and industrial settings.

I was an informal advisor to Italian government laboratories in Milan and Rome which analyzed for dioxins associated with the Seveso incident, advising them on how to calculate findings from raw data and how to present the data for interpretation by the toxicology community. This was during a time I was training Dow laboratory personnel in Germany to perform dioxin analyses.

I was involved in developing methods for analyzing Agent Orange (used as a defoliant in Vietnam) for the US Government .

With this background, I have developed informed opinions about dioxins and their hazards.

• There are many chlorinated dioxins, but only a few are toxic; the ones with chlorine in the 2,3,7, and 8 positions.
• If an animal is exposed to a wide range of dioxin isomers (such as fly ash from combustion), the body retains and concentrates the toxic isomers in fatty tissues. This implies that there is a receptor which binds the 2,3,7,8-dioxin isomers. This receptor has another purpose, but the dioxin molecule happens to fit.
• The bioconcentration factor in fish is approximately 3000 (the fish end up with 3000 times more dioxin than the water they live in).
• Dioxin acute toxicity (high single doses) is very species dependent. e.g. Mice are more sensitive than rats, and man is on the low end of the sensitivity scale.
• Long term low level exposure produces an increased risk for some kinds of cancers, and affects the immune system.
• All humans have a natural low level of dioxins (generally less than 1 part per trillion).

My dioxin web site