Creosote (the real one) - what are the dangers please?

I have a large quantity of reclaimed hardwood boards, and many of them have been treated with genuine creosote from the 1950s.

Some of them (that are not being used for construction) will need to go over the jointer, so I'm wondering what precautions I should take. I will use a 3M P2 mask, but is that enough? This particular mask is known to be cat fart proof, FWIW (not sure how fine the particles in a cat fart are compared to creosote dust :D).

The boards that I do use for construction or fencing will have the creosote left on.

Plant and coal creosote were often mixed as the wood creosote was a less effective preservative. Thus it is likely that your timbers were treated at least in part with the coal tar product. That said, creosote is banned or heavily regulated in many jurisdictions. For example used railway sleepers (creosoted) are considered hazardous waste here. Unless you have no alternative I'd recommend leaving the stuff alone, use it for parking blocks or supports for a pier and beam building. If you must however I'd recommend a mask that covers your eyes too and preferably a full body suit to keep the dust off of your skin. Make sure there are no innocent bystanders anywhere downwind as well if you mill it.

Cheers,
Rob

Read the MSDS for yourself.
eg http://kmgchemicals.com/wp-content/u...e_Oil_MSDS.pdf

Have a look about what it says about the type of mask that should be used, certainly a passive type mask is not considered safe enough.

My concern would be that the machining process will heat the wood dust which may produce PAH (Poly aromatic hydrocarbons) gasses which, along with any other gas components, will pass straight through anything except a genuine gas mask.

Even if you use an appropriate mask skin and eye exposure can lead to ongoing problems.

Although not life threatening one of the real PITA effects is ; "May cause photosensitization, evidencedby repeated occurrence of a dermatitic rash on exposure to sunlight. "
If you contract this it means every time you go outside you will have to be covered up agains the sunlight.

Regular creosote is thought to contain around a half dozen suspected carcinogenic compounds but only one is supposedly definitely carcinogenic (Benzopyrene)
FWIW Apart from Benzopyrene and the PAHs (i.e. only when its is heated) the components of common creosote all have HIGHER air exposure limits than ordinary wood dust (which I think is around 10 x higher than it should be).
Benzopyrene has a 1000 times lower exposure limit than wood dust.

P.S. Whatever you do DON'T BURN IT! If you do you'll vaporize a significant fraction of the toxins creating a cloud of nastiness.

Thank you chaps. I thought it was pretty nasty stuff. Will read the MSDS.

I have absolutely no intention of burning it!

FWIW when I was a kid we lived in a 3 bedroom wooden house that had been externally painted with creosote. The house was one of many in the Timber milling town where we lived. When they caught fire they went up up like they had been doused in petrol - very spectacular. I remember one house that burn down and there was nothing left except a small amount of white karri ash the remains of the fireplace chimney. The scariest time was during bushfire season as all it often took was one ember and that was it. I remember filling up buckets and tubs with water when the bushfire started to get close to town.

The MSDS only refers to it in it's liquid form. Now it still has to regarded with the greatest respect, but i would have thought less dangerous when dry for 60 years, at least for giving off vapours etc.

Would it be something that the CSIRO might know about?

The year was 1977 I think.

I, a mere innocent spotty youth spent my summer holidays in Tassie's Forests earning beer money.

One of the tasks was a week spent in a succession of pine plantations holding a large red rubber meteorological-type helium-filled balloon on a string. They didn't have anything else for me to do, and said they kept this particular job for only the cleverest interns.

Actually it was to show flight paths for aerial spraying.

The spray was a special cocktail of 2,4,5T and 2,4D, mixed with a liberal proportion of diesel as a wetting agent. This is basically known elsewhere as Agent Orange, although the actual mix of the cocktail was tweaked so as to be toxic to most if not all woody weeds, but relatively benign to the P. radiata.

The rubber/latex/whatever in the balloons lasted all of about one single overflight before succumbing to the diesel and deflating. We were issued with heavy plasticated bright yellow ponchos and souwesters for protection. These lasted all of about 5 minutes in the summer heat, scrambling and racing to keep ahead of the aircraft. If you recall the summer of '76-'77 was bloody hot.

Instead the raincoats were tied to the end of the largest sticks we could find. We waved these like madmen for the pilot to see while he drenched us with his chemical cocktail.

And drenched we were. Literally dripping with the stuff. All my clothes had to be thrown away, my bedclothes, mattress, the lot. People wouldn't let me in their house, refused to let me ride in their car, for weeks afterwards. I even had to shave my head.

But we were told it was safe! Only poisonous to plants. It was only later that we found about dioxin contamination, of the fact that these chemicals had been banned in many OECD countries, and of the side effects. Of the fuss and protest about toxic chemicals leaching out of these plantations into the ground and surface water.

My wife occasionally looks at me strangely and says that this explains a lot. I wonder what she means?

Quote:

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Originally Posted by FenceFurniture

The MSDS only refers to it in it's liquid form. Now it still has to regarded with the greatest respect, but i would have thought less dangerous when dry for 60 years, at least for giving off vapours etc.

Would it be something that the CSIRO might know about?

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I know CSIRO will want to cover their behinds so they will definitely say, "Don't re-use it".

Quote:

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Originally Posted by BobL

I know CSIRO will want to cover their behinds so they will definitely say, "Don't re-use it".

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Heh heh, that went through my head about a nanosecond after I posted. Then I thought Master Builders Association. Nah, butt covering again.

There's negligible chance of evaporative vapour contamination of course.

In the machining, however, the stuff could/would become aerosolised into minute particles. Your mask is an absolute must.

I've always found (from concrete chasing and cutting) that unless freshly shaven it's nigh on impossible to achieve an airtight seal around the face. A little barrier cream on hands and face can help to seal against the nasties too, as will wearing a beanie, which prevents settling in the hair for later inhalation.

Quote:

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Originally Posted by Ratbag

....unless freshly shaven....

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Pffft. I'm always freshly shaven. :roll:

From what I understand the major risk involved in creasote is with it in its liquid form and the process of applying it.

The riks various would have to disipate over time as the volotiles disipate.

There is heaps of creasote treated timber arround....the housing commission and others used to routinely slather fence pailings and the pailings & slats arround the outside of houses on stumps.

In short they creasoted everything below the stump caps..and fairly regularly.

If its on an old house and it aint painted..and still standing it was probably slathered in creasote at some time.

Its still available down my local produce and it is still commonly used to treat the bottoms of fence posts and power poles.

I have used it to treat fence posts and power poles as there still is nothing as effective.

mostly it is applied by dipping or pouring these days.

I certainly would not be keen on spending day after day slopping it on fences with a 6 inch brush and a 2 gallon bucket as was practice.

Hell they used to spray the stuff....a common method was the use of a filthy black pressure tank and a spray wand

I can see how those guys could get bad health effects.....staying arround the fresh fumes and getting it spotted all over from the splashing.....long sleves and trousers would be NBG because it would soak straight thru.
A combination of creasote and extended sun exposure....near guarantee of skin cancer.


Now back to the real world of today.

The dumps will clasify almost anything that clearly has not been growing in recent times as treated timber and clasify it as toxic waste.....our old mate Exador took a load of bark edged scantlings to the tip once and they wanted to clasify it as "treated timber".


ANYway.....can you smell creasote in the timber in question?

It soaks in a little way.....but below will be clean timber, particularly if it is hardwood....so have you put a cut thru the material to see how far the creasote has got in.

depending on how you mill and dress the timber you may be able to cut the creasote contaminated portion straight off without machining too much actual creasote.

while a lot of people have made a big deal about creasote.....if what you have is old and not been treated in decades....its probably no more hazardous than many other things you have machined.

You have to treat any wood from an old house with some caution.....most of the houses in the area I grew up in where drenched underneath and in the cieling space with dieldrin every 12 months for decades.....that stuff is persistent....ya don't wnat to be breathing that.

Maybe on step further with the PPE, a little more care and don't leave the waste lying around and don't put it in the garden.


As far as burning it.....well I would not cook over it and I'd keep out of the smoke.......UM how do ya think they make creasote.....they burn wood.

Its not like it will leave heavy metals arround like burning CCA treated timber.

cheers

Hi All,
Back in the 50's the SEC of Vic. received these new Black looking Poles. Great, until you touched them with a bare hand. Then came the rather Warm Days, & the Boys working up in the air, came down & were a Red as Beetroot, of course Burnt by the Creosote in the Poles.

Can't remember how we got over them, but nobody liked working with them at all.

In fact there are still some in the ground, to this day.

The other use was by the Pole Inspectors, who wood dig around a pole, pour Creo into the hole & mix it up, to preserve the pole from whatever.

Brett

The primary problem with creosote is that both the liquid and the fumes from the liquid (no actual contact required with the liquid) remove the skin's natural protection to ultra violet. Consequently, any time spent in the hot Australian sun following exposure or contact with creosote gives a good insight to purgatory. As the victim of this more than 30 years ago I can vouch for this being the case.

The question remains as to how the product performs after many years. I would suggest that all the volatiles have long since gone. The dust from sawing or planing operations should be treated as if it were one of the worst woods for producing allergic reactions. If the surface of the timber can be removedby sawing to a few millimeters that would be preferred. The cresote doesn't penetrate very far into heartwood. It is the reason Spotted Gum is a preferred power pole timber. The wide sapwood absorbs the creosote to the full depth. Creosote penetration can be increased by heating the creosote as there is a vacuum process that occurs as the liquid cools.

There is also the question of how much you will be doing with this treated wood. I am surmising that it will not be for the rest of your life.

Regards
Paul