Analysis of Dioxins
Dioxins have existed since ancient times. The dioxin is produced when chloride compounds and saline matter are burned together. Trees and grasses have almost no saline matter, and hardly any dioxin is produced when these are burned in mountain fires.
Since ancient times, when magma and seawater are mixed as a result of fires and volcanic eruptions, dioxin has been produced from the mixing of chlorine from the seawater and oxygen from the air. However, until now, dioxins have not remained.
Actually, it is because the trace amounts of dioxin that arise from trees and grasses all decompose by ultraviolet rays from the sun. Further, dioxins in the soil also have decomposed gradually.
A volcano is a storehouse of chloride compounds, but dioxins do not arise from volcanoes. New types of garbage incinerators have been developed which use volcanic ash.
However, in modern society, we are living in the midst of chloride compounds. Plastic materials are a representative example. It is because everything around us is based on chloride compounds. So, the problem is the various types of dioxin that arise from plastics.
Chloride compounds are also in printing ink, so when newspaper is burned, the amount of dioxin that arises is many hundreds of times the dioxin in wood materials.
Of the various materials, the largest quantity of dioxin arises from waste plastic incinerators. People who smoke probably do not want to hear this, but in Japan in one year, 16000000000000 picograms of dioxin are released from cigarettes. (Note: Please count how many zeroes in that figure.)
A lot of dioxin is released from broiling fish with salt, but did you know that the most dioxin is released from burning household garbage? Although there may be no smoke, dioxin is produced. However, at high temperatures above 1000 degrees C, dioxin decomposes. Self-governing areas in Japan that have their own high temperature incinerators probably do not separate the collected garbage into the various types of garbage. At high temperatures, nitrogen oxides increase so it is necessary to attach equipment for denitration reaction.
As for automobiles, since the quality of diesel fuel is poor in Japan, a large amount of black smoke is produced from engines with a mechanical pump, but less black smoke is produced from engines that have a new electronic fuel control system. Since compared to diesel engines, gasoline engine automobiles produce a relatively large amount of CO2, in Europe, many people are switching to diesel automobiles for environmental conservation. Why is this so? The reason is that in Europe, the sulfur content is lower in diesel and the efficiency is higher than for gasoline engines.
In Japan, sulfur-free gasoline has come on the market.

Notes and Precautions:
From the year 2003, the sulfur limit for diesel (light oil) will be 50 ppm, or 1/10 of the present amount. In 2005, it will become less than 10 ppm, and decrease like the sulfur content for gasoline.
Engines designed for the 8 metropolitan cities in Japan will not be able the meet the year 2000 regulations. The engines have improved in terms of environmental measures compared to gasoline engines. The air in the Tokyo metropolitan area might become cleaner than in the rural areas (because the older type of polluting automobiles are being sold in rural areas instead of the metropolitan areas). In the future, unless we can make things that do not consume oxygen humans might die from suffocation.
Gasoline and light oil sold after January 2005 will have sulfur content of less than 10 ppm.
The new model diesel injection produced by Japan Bosh injects at a pressure of 2000 bar, and after combustion, by passing through a catalyst and filter, the exhaust gas is clean compared to new gasoline engines.

Environmental engines that have passed the 4 specifications for Euro diesel have begun to be sold. Further, the Minister of Foreign Affairs has reduced ODA to China and said that funds given to China must be routed to environmental measures, and acid rain and other environmental pollution that comes to Japan must be stopped. I think the Minister has changed quite a bit.

Regarding dioxin:
To make bamboo charcoal, about 20 kg of material is burned. The amount of dioxin produced is probably less than that from one pack of cigarettes. In the beginning, at low temperatures, the amount of dioxin produced is small. In my kilns, the temperature reaches 1100 deg C. The ashes in the firewood chamber go into the kiln with the air that is blown in, reach high temperature, and the dioxins are decomposed.
So, why is there more dioxin from cigarettes? It is because of the residual chlorinated pesticides. If there were no agricultural chemicals, good quality tobacco leaves could not be produced. The main constituent in the pesticides is composed from chlorinated compounds. It can be considered that the dioxin that falls on the ground is decomposed in the soil. But, when leaves are used, such as for tea, the chemicals that fall on the leaves go directly into the consumerfs mouth. So, it is necessary to be careful about tea that is grown in areas where dioxins are in the air.
Polyvinyl chlorides are chlorinated compounds so when these are burned, a large amount of dioxin is produced. But there is no chlorine in the plastic drink bottles (PET) that everyone uses. Further, there is no chlorine in styrofoam (foam polystyrene) so if it is incinerated, dioxin is not produced. The smoke from making charcoal is from the dry distillation of the bamboo or wood and does not produce dioxin. If you dilute the wood charcoal vinegar and put it on dried fish, it will become smoked fish.
If bamboo vinegar is collected from the smoke, and left to rest for more than 6 months, it will separate into 3 layers. The middle layer is taken and purified. It is about 3500 yen ($30) for 100 ml for vinegar from mountain cherry tree wood.
If there is no minute toxic constituent in bamboo charcoal vinegar, afflicted parts of the body will not improve (This is according to the late Dr. Kishimoto.) If animals and plants are carbonized and the mineral constituents are compared, the constituents will be exactly the same. (Also, according to the late Dr. Kishimoto).
These days, it has become more difficult to burn fallen leaves in Japan. The regulations on burning have become more stringent because people were burning plastics (containing vinyl chloride) along with the leaves, and this produces toxic dioxins. From the past, people have been burning leaves. A minute amount of dioxin is produced but it is not a problem in daily life. The alkaline ashes from burning leaves can neutralize acidic soil.
It seems odd to compare exhaust from automobiles and smoke from burning fallen leaves, but they are given similar treatment under government regulations since both produce smoke.
It is economically more effective to decompose dioxins by using ultraviolet rays from the sun. Ashes from burning fallen leaves are alkaline, so if the ashes are spread into crop fields, acidic soil will become neutralized.
Airborne acidic substances from mainland China, and tiny particles in black smoke from Southeast Asia are more of a concern. I hope that everyone will take more interest in chemical climate information from Tsukuba (scientific research area in Japan).
Everyone, letfs produce a lot of smoke from making charcoal, and envelope the surrounding people in smoke. The ashes that remain are alkaline and valuable. The ashes can be spread in crop fields or flower gardens to give the plants vitality.

This text was based on discussions with Dr. Teiko Oomori, former professor of Toho University, with some modifications and additions.