View topic - Burning plastic in the campfire - how it is harmful

I suppose some of us realized it was a bad thing to do, but didn't exactly know why. I was in this camp until someone challenged me to say why it was harmful beyond "pollutes the air and introduces harmful stuff into the environment". It took about 5 minutes of research to learn why.

Sorry if I'm preaching to the choir, but the summary is that it releases dioxins and furans. Below are some quotes I cut and pasted from various web-sites, posted below each. Hardly academic, but maybe of interest to someone:

What are Dioxins and Furans?

“Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), commonly known as dioxins and furans, are toxic, persistent, bioaccumulative, and result predominantly from human activity. Due to their extraordinary environmental persistence and capacity to accumulate in biological tissues, dioxins and furans are slated for virtual elimination under the Canadian Environmental Protection Act, the federal Toxic Substances Management Policy and the CCME Policy for the Management of Toxic Substances.”
(http://www.ccme.ca/ourwork/air.html?category_id=91)

Where do they come from?

Six priority sectors accounting for about 80% of Canadian emissions in a 1999 inventory were identified as priorities for early action. These are waste incineration (municipal solid waste, hazardous waste, sewage sludge and medical waste); burning salt laden wood in coastal pulp and paper boilers; residential wood combustion; iron sintering; electric arc furnace steel manufacturing; and conical municipal waste combustion. Canada-wide Standards for Dioxins and Furans were developed for all but residential wood combustion, which is being dealt with through the PM and Ozone process.
(http://www.ccme.ca/ourwork/air.html?category_id=91)

How do they get into our bodies?

Dioxins are linked to many serious health concerns including increased risk of cancer, developmental problems in children, diabetes, cardiovascular disease, harm to the immune system, endometriosis and hormonal disruption.
The health risks do not come so much from breathing the air containing the pollutants as they do from eating food. Poisons released into the air by garbage burning eventually fall back to earth and contaminate plants, soil and water. Animals consume them and they make their way up the food chain. Dioxins accumulate in the fat of animals and fish and are passed on to people when we consume their flesh or milk. It is this long-term, gradual exposure in the fat of the human body that is the problem.
(http://www.realaction.ca/backyardburning.htm)


What are the health hazards associated with these
chemicals according to Health Canada?

The studies show that dioxins and furans have the potential to produce a range of effects on animals and humans. Health effects associated with human exposure to dioxins include:
• skin disorders, such as chloracne
• liver problems
• impairment of the immune system, the endocrine system and reproductive functions
• effects on the developing nervous system and other developmental events
• certain types of cancers
(http://www.hc-sc.gc.ca/hl-vs/iyh-vsv/en ... in-eng.php)



Some other interesting links about burning plastic:

Illegal, too:
http://nfuontario.ca/upload/files/userf ... lastic.pdf

Campfires aren’t hot enough:
http://www.gov.pe.ca/environment/burning-plastic)

"Most toxic chemicals known to science":
http://www.ejnet.org/dioxin/

Sources of Dioxins and Furans:
http://www.newmoa.org/prevention/topich ... e_from.htm

Here’s a nice brocure:
http://www.calgaryhealthregion.ca/publi ... in-eng.pdf

So better question is not: "why is it bad?" but "why is it worse than burning wood?"

Wood also releases plenty of dioxins and furans. If you pack it out and dispose of it, the municiple incinerator will release these compounds.

Serious question...

_________________
I like canoes

Thanks for the research. I normally reuse my plastic bags unless they contained meat or cheese so I did a little research of my own and found that Baggies, Saran wrap and Ziploc bags are dioxin free according to their websites. I wonder if other food type packaging wouldn't be the same. I burn all my cigarette butts rather than pack them out so there's probably an associated plume of dioxins involved with that but hey, I'm on vacation!

The question that remains in my mind is along the lines of, isn't burning a speedy form of oxidation? Wouldn't rotting wood, plastic, whatever still release, everything they are made of, (mostly carbon in the case of wood) given enough time?

No clue. Just lobbing it out there for curiosity's sake.

_________________
Enjoy the Journey

Well, I'm no expert, but I read that those municipal incinerators run at around 1800 degrees F with plenty of oxygen, which somehow more completely combusts the toxic emissions. That is from:http://www.gov.pe.ca/environment/burning-plastic

In my city we don't have municipal incinerators that I know of. Much plastic can be recycled also.

As to the wood issue, I also read that core samples show insignificant levels of these compounds prior to 1940. That is from: http://www.newmoa.org/prevention/topich ... e_from.htm

Like I said - the chemistry here is above my level, and no doubt there are arguments to be made. However, it seems that there is considerable credible evidence against burning plastic trash in a campfire or burning barrel. My thinking is that if I was strong enough to carry it in I can carry it out.

Like you, I'm not an expert. But I am inclined to agree with you.

This report seems to be conclusive .



http://www.dhs.wisconsin.gov/eh/HlthHaz/fs/WoodBrn.htm

I've been reading a bit more, and it seems that the dioxin that is the persistent, bio accumulative pollutant is created when plastics are burned, not in the plastics themselves. Put another way, burning does not release dioxins, it produces them.

If this interpretation is correct, it means that the plastics will not be a source of dioxins as they break down in a landfill, unless they are exposed to very high temperatures. If so the fast/slow oxidation argument may be invalid.

Any chemists want to chime in and let me know if this is the case or not?

I'm not a chemist either, but I work in a pollution control related field. I have done some web surfing on this issue. But I may not totally know what I'm talking about.

As far as I can tell, chlorine has to be present during the combustion process for dioxins and furans to form. That is why one of the reports cited above talks about burning of salt-laden wood as a source. Salt is NaCl which is the source of the chlorine. I'm not sure where the chlorine comes from in burning non-treated, non salt-laden wood. Maybe there is a small amount of chlorine in normal wood structure, or tree roots suck up chloride ions from the soil. Anyone know?

PVC seems to be the most problematic plastic. PVC is polyvinyl chloride, which is a source of chlorine. However, this U.S. Forest Service study
http://www.fs.fed.us/t-d/pubs/htmlpubs/ ... /index.htm
seems to show that burning plastic bags (which I'm gonna guess is a polyethylene, but hard to say) is a source of furans. Polyethylene does not have chlorine in the pure polymer, so maybe there's chlorine in the plasticizers, or dye. I don't know.

I share your concerns about this, mr_c18, mainly because the fire pit is often a food prep area. Who wants toxic ash blowing onto the bannock? If you look at the Forest Service study, several different packaging materials significantly increased the lead level of the ash over that of pine wood.

I wish someone would sample ash from some well used campsites and see just what pollutants are there. Short of such info, I prefer to act with caution.

So don't pee in the fire pit (salt), burn salty food, or burn garbage, and you can feel good about leaving a clean site for the next person.

As far as plastics in landfills, I don't think they are going to break down fast enough to be an issue any time soon. Unless the landfill is on fire, which does happen.

Here's a method that proves out plastics can be safely recycled.

http://www.plastic2oil.com/site/home

One thing I know from 20 years working in the environmental field is that few things involving the environmental and toxicological effects of our actions can be dissolved down to a simplicity of a discussion group posting (incuding the posting I am currently typing). But, I can tell you that here in Michigan our air quality department views the residential burning of trash as significant contributer to air pollution. We all can understand that efficient combustion produces the least pollution. As we all know, a pile of wood smoldering on the ground is the least efficient way to burn wood, so it carries that that same stinky fire is probably the least efficient way to burn plastic too. In addition, I have sampled the soil in hundreds of backyard campfire circles where trash has been burned. Nearly every burnpile, or campfire circle contains compounds in the soil that would make the property technically an environmental site according to our state rules. So I have little doubt that nearly every campfire pit contains what amounts technically to environmentally contaminated soil in addition to the air emissions from incomplete combustion of any waste that was burned in the fire.

But, that is not to say that hauling your trash our of the bush, and properly disposing of it in a landfill has zero environmental impact either. Landfills are currently constructed in a way to preclude the decomposition of the matter in the landfill. Materials that regularly decompose in a season or so in the natural environment (like untreated paper) require centuries to decompose in a landfill, and plastics, and other hydrocarbon based materials will take much longer to decompose. While scientific studies have been done regarding the decomposition of trash in landfills, the reality is that Landfills are simple ways to concentrate our waste in location where they can be monitored, but create an untrue persepctive that the waste will never create further environmental problems for future generations.

So in summary, trying to find the most environmentally defensible method of disposing of plastics within the the economic realities that we are all currently living is a fools game.

PK

Maybe there will be a rush to extract resources from landfill in 50 years time when resource prices get high enough!

It has been depressing to see how waste (both solid and liquid) is dealt with in Canada compared to Europe.

I used to think the episode of the Simpsons where they moved the town when the landfill became too full was just a joke. Now I'm not too sure...

_________________
http://www.canoepaddler.net

PK, I'm curious what kinds of contaminants you have found in the backyard campfire circles.

When Gail used to post here, she described burning baby diapers in the campfire... that was about the same time I got my twig stove.

...the howwah... the howwah...

_________________
><((((º>

Obviously most organic compounds combust. Although I have seen some of the non-volatile organic compounds (dioxins and polycyclic aromatic hydrocarbons, PCBs) in burn areas within the soil. Most organics are emitted in some modified form...from water vapor and CO2 to more complex organic vapors and smoke (particulate) into the atmosphere. But we see elevated concentrations of any contaminant that doesn't burn at relatively low temperatures... so metals are quite common, there are some relatively non-combustible organics, as well as inorganics to a lesser degree.

PK

I also find it discouraging to know that local waste isn't ever just a local problem. We have ways of sharing our pollution worldwide through the atmosphere and hydrosphere. It provides very little incentive for any local government to take action. I think this might be a moral hazard, in economic terms.

I used to think that I could escape the pollution we have created by just going back in the country a bit. Then I learned that the Greenland Inuit have some of the highest concentrations of PCB's in their livers and realized there is nowhere on earth untouched by our industrial pollutants.

Something I thought was somewhat joke-like... people buying homes next to an airport, then after living with the jet noise for a few years, they form a community and demand that the airport be moved.

Modern consumerist society will encourage it's mainstream residents to produce plenty of garbage... those not members of that sweating herd, producing little or no garbage, will be seen as very strange.

_________________
><((((º>