Ipe and Lapachol

[Paul K. Murphy]

This can be viewed as a PSA of sorts.
Ipe, and some other woods contain a chemical irritant called lapachol. Central and South American woods seem to be the principal offenders.
Lapachol is a greenish yellow powder. It's moist. It will stick to your clothing, irritate your nostrils and eyes. The tiniest splinter will slowly administer the offending irritant like a nicotine patch. I've learned to get even the tiniest splinter of ipe wood out of my flesh tout de suite.
It is strange to saw a walnut colored wood, only to be treated to a stream of greenish-yellow, moist sticky dust.
Take precautions! It's like the wood of the Poison Oak Tree.
A photograph to drive home the point:


https://en.m.wikipedia.org/wiki/Lapachol

[JR1]

I've done a fair amount of work with Ipe. The amount of lapachol in a given sample varies widely. Hand tools liberate much less than power, particularly the table saw. An N95 dust mask is advisable, as are gloves and clothing to be washed separately. Lapachol was trailed as an anti cancer drug but it proved to be too toxic.

It can interfere with glue and some finishes. Wilpping the wood with alcohol or MS eliminates the problem. It is not absorbed through the skin; but ingestion or inhalation are inadvisable.

[deeno]

I lived in Brazil for 4 years and learned the hard way to be very careful when working with IPE and wood in general. Some people never have problems with it. I used to watch the guys that worked in the lumber mill by my house and they would be around this dust all day long. I built a workbench and a winetable out of IPE and by the time I was finishing the winetable I was exibiting astma like symptoms. After months of racking my head as to what could have caused this I could only point it back to my woodworking. Then I researched the woods toxicity and learned a lot. It did not take long to develop an intolerance for this wood. I used to be covered in dust when running large stock in my band saw and table saw to get it to manageable size for hand tools. I worked outdoors so I tought that there was no need for a mask since there was a lot of fresh air. More than once my eye would be inflamed, almost like pink eye. Be careful and wear a mask and rubber gloves and wash your clothes after your done. I do this now for any type of wood I work. Protective equiptment is very cheap compared to your health. Not trying to sound negative just trying to help avoid somebody going through what I had to go through.

[Bob10]

While I don't like the dust I have worked with lots of Ipe with no reactions. The first time blowing my nose after working with it was a bit alarming but not much else. I am starting to use my dust mask more as I get older so I imagine in the future I will be masked while working with Ipe but I find it strange how it effects people so differently

[Bill Holt]

I have a fair amount of reclaimed Ipe and have worked some of it without any reaction to the dust so far. But like Paul said, the smallest splinter causes a very "distracting" pain if not removed immediately!

[Bob10]

it is almost like getting a metal sliver and it doesn't seem to want to leave once it's dug in

[Paul K. Murphy]

Ipe splinters I've gotten are like little splinters of broken glass. Even two or three days later, they're like that. Most woods soften, just like a moistened or cooked noodle will, but not Ipe. Bear in mind, I've worked in this trade for thirty six years. Complaining about splinters isn't what I do; it seems alien to me.
I knew I was having problems with the stuff, remembered something I read, and did my research. My eureka moment was when I saw it in black and white. "That's why those splinters are so painful", I said to myself.
Not every specimen of wood has the same concentration. The worst examples are really remarkable. Here I am cutting a walnut colored wood, and everything around me has a profuse, fine dusting of fragrant yellow powder.
At least it isn't the Manchineel tree. Before my Ipe experiences, I might not have believed the stories I'd heard about that one. "The Little Apple of Death" tree. Be glad you're not working with that one.
https://en.m.wikipedia.org/wiki/Manchineel
I have read accounts of people who have ingested the fruit of that tree, and it isn't pretty.

[Boatman53]

I made a 16' X 16' deck from Ipe. It went well but near the end I developed a rash. The next time I cut some Ipe (one small cut) I had a really bad reaction that took weeks to clear up. I had to give my shop a cleaning like it never had before and don't go near the wood at all. I won't even touch it.
Be careful out there.
Jim

[Curlycherry]

This is interesting because I have worked with IPE a lot and have gotten the slivers of death. My screened in porch floor is IPE and my wife loves it. In the future we were planning on using IPE for the floor of our 3-Season porch, but now that has me wondering. Can IPE be used in an "inside" location, ie one that is not a deck or screened in porch?

[Bill Holt]

Curlycherry said:

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Can IPE be used in an "inside" location, ie one that is not a deck or screened in porch?

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I used it on a small cabinet and a box; it finishes beautifully with oil base wipe-on.