People’s couches are laced with carcinogenic flame retardants, but that seems to be ok. 
I would suppose any nasties in wood vinegar are fairly short lived, probably evaporate fast in the open.
Besides, we smoke foods, sit by fires, etc, shouldn’t be a real hazard.
I know some years ago the EU was talking about listing pine tar, had sail boaters upset, not sure if that went through.
I think we have a lot of other chemicals in our daily world to worry about first.
And we have done these kinds of things since we invented fire. 
And there are many instances were ancient corpses have shown signs of lung cancer.
Rindert
Be cautious here. Some town gas engines will only run on town gas and town gas is not wood or char gas. I learned this first hand from people that run these engine. Took them a long time to figure that out. I am sure some will run on wood gas but why bother with the sea of ic engines all around. How about derating a modern engine? Slower rpm? How about taking a 6cyl and running it on only two jugs? When that wears install the other pair of cylinders, still one more left.
The Black Tar Water that I dump out of my gasifier condensation tank is the best free weed killer I have seen, and you can see where you have used it. The gravel dirt road be side us and the cherry orchard has goathead thistle plant or puncher weeds. A flat growing weed with yellow flowering blossoms and very sharp puncher seed. Tough on small tires, bicycle, wheel borough, yard tractor mowers.
That black juicy kills the weeds dead.
Bob
We have goatheads around here too. Good to know. Thanks.
Rindert
I would like to retract the statement about wood vinegar being studied to treat cancer . and add statement about what I actually meant but forgot I meant something else .
Phytochemicals are naturally occurring plant chemicals (phyto means plant in Greek). They provide plants with color, odor and flavor. Once we eat them, however, research shows they can influence the chemical processes inside our bodies in helpful ways.
Thousands of phytochemicals have been identified so far, and scientists have only begun to investigate their promise.
Phytochemicals are chemical compounds produced by plants, generally to help them thrive or thwart competitors, predators, or pathogens. The name comes from Greek, Modern φυτόν (phyton), meaning ‘plant’. Some phytochemicals have been used as poisons and others as traditional medicine.
As a term, phytochemicals is generally used to describe plant compounds that are under research with unestablished effects on health and are not scientifically defined as essential nutrients. Regulatory agencies governing food labeling in Europe and the United States have provided guidance for industry limiting or preventing health claims about phytochemicals on food product or nutrition labels.
In regards to chemicals or dust stuff in our lives. I think of it as playing Russian roulette. Sure would be nice to start out with no bullets in the revolver and say we do. So we play with automobile stuff like brake cleaner or what ever. That is like placing the first bullet in the revolver. So we pull the trigger, see no bang. This is fun! Now we smoke or grind on nasty stuff with no mask. Add one more bullet, click. See, no bang. More fun and games. Lets account for industrial pollution. One more bullet, click. See, no bang. The fun never ends. Now lets add the distillation chemicals with no regard to your well being or what ever you play with next. Add one more bullet, ???
Just a view from an old fart.
And then we can’t figure out why the high incidence of cancer, lung disease heart disease, etc.
Pine Tar Shampoo and Pine Tar Conditioner
Only a limited amount of research has been done in recent decades on the efficacy of pine tar to treat skin conditions. The studies I did discover showed pine tar had little or no medicinal value. Based on this, the US FDA has determined pine tar is not an effective drug. That means pine tar soap cannot be legally sold to consumers in the United States as a medicinal product. If a seller makes an outright claim or even implies that pine tar soap is a drug (a medicine), the FDA can take disciplinary action.
Amazon review
It’s been great for psorasis of the scalp. Recommended to me by my dermatologist who has not steered me wrong.
The U.S. FDA recognizes coal tar as “generally recognized as safe and effective” (GRASE) for use as an over-the-counter topical medication for skin conditions such as dandruff, seborrheic dermatitis, or psoriasis.
Coal tar has been used to treat psoriasis for more than 100 years. You can find it in shampoos as well as creams, oils, and lotions.
Shampoos with coal tar help with scaling, hardening, and thickening of the skin on your scalp by slowing down the growth of skin cells. They also can ease itching and make your scalp look better overall.
Occupational exposure to coal tar or coal-tar pitch increases the risk of skin cancer. Other types of cancer, including lung, bladder, kidney, and digestive tract cancer, have also been linked to occupational exposure to coal tar and coal-tar pitch.
In California, you’ll find cancer warnings on some coal tar products you can use to treat psoriasis. This warning was added to products in California due to:
Animal studies (where the animals were exposed to a lot more coal tar than we would use to treat psoriasis)
Occupational studies (where a person works with industrial coal tar)
To date, studies fail to show an increased risk of cancer in people who use coal tar to treat psoriasis or atopic dermatitis (eczema). People who work with industrial coal tar, however, have an increased risk of developing cancer of the lungs, scrotum, and skin.
I am wondering if this could be related to the safe disposal of chemical waste by injection well from Kingsford Charcoal ?
In 1995, a house in Kingsford, Michigan, developed explosive levels of methane (CH4) that was degassing from the aquifer below the house. Methane built up in the basement, and eventually an explosion occurred. The methane was likely the result of the microbial degradation of organic compounds in a plume of contaminants emanating from nearby industrial areas. The operation of charcoal production and other industrial facilities led to the release of organic compounds, such as pyroligneous acid, creosote, and tar into the subsurface. As the organic compounds migrated away from the industrial areas, microorganisms converted the organic compounds to methane and carbon dioxide, creating plumes of methane in the subsurface. The methane moved with the natural ground-water flow system and escaped to the surface.
To help determine the source of the methane-generating ground water, USGS scientists used compound-specific carbon-isotope analysis. The isotopic signature of the contaminants was used to help identify if there was one or more sources of contamination and to help understand the natural degradation of the contaminants.
spending ridiculous amount of time boiling down gallon of wood vinegar . In a pot on sheet metal over a fire boiling for hours .
Acetic acid is a compound that, when pure, is water clear and freezes just above room temperature. Pure acetic acid will seriously burn you if it contacts the skin or eyes,
Vinegar is 5% acetic acid.
When it comes to cleaning, vinegar is the jack of all trades. Use our powerful vinegar in your home or garden for hundreds (yes, hundreds!) of different tasks. And it’s certified for organic use so you won’t feel guilty using it around your home. Sounds like a natural fit to us, but maybe we’re biased.
Green Gobbler’s 30% Vinegar is great for everyday cleaning, gardening and laundry. Using vinegar is a more natural way to eliminate everything from mildew to rust. Our vinegar is 6 times more powerful than standard vinegar, so it packs a punch.
Whether you’re using it as a handy garden helper or a powerful bathroom cleaner, you can trust Green Gobbler’s 30% vinegar to get the job done. Remember to dilute the vinegar accordingly for the task at hand.
I just want to get rid of this stuff . yes it is dangerous .
ashes are alkali and should neutralize acid , after a rain it will be gone .
Just trying to burn brush .