MDF Sawdust

[Bob Eustace]

Can some kind Botter who is also into gardening tell me if it is safe to plonk MDF moisture resintant grade sawdust into the compost bin? I have an idea it has formaldehyde in it??? We never put treated pine in the compost as out here it contains arsenic and copper sulpate. Would like to use the MDF though if possible as we make a lot of the stuff.

[Shane]

The normal MDF you can compost and the formaldehyde breaks down completely. Not sure about the Moisture resistant stuff. There have been scientific testing to confirm the formaldehyde does break down and is safe in compost.

Shane.

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CDAQFjAA&url=http%3A%2F%2Fportal.ncdenr.org%2Fc%2Fdocument_ library%2Fget_file%3Fuuid%3D75559bcd-1518-4873-a6eb-39fea773c614%26groupId%3D38322&ei=EIl_UZ7fCK7xiAez-4GYCg&usg=AFQjCNGLovgca1H6BFTVfTeRwYiCfskjIw&sig2=hWBtYZDjhaOOmpTJky_YvQ&bvm=bv.45645796,d.aGc&cad=rja

[steve_g]

I'm not sure what "brand" of moisture resistant MDF you have but the MEDEX brand by SierraPine I use has "no added Formaldehyde". Because it's 100% post industrial recycled wood fibers there my be existing formaldehyde containing products in the mix.

SG

[Bob Eustace]

Thanks Steve and Shane. If I drop off the radar in 12 months you'll know why! It will solve a waste disposal problem for s though.

[davidp]

Hi Bob,

MR MDF has a higher level of resins than STD MDF. I have composted it in the past. The biggest problem is that it takes some time to breakdown.

At Kinglake you should have lots of room to establish a large compost heap. Keep turning it and add lots of green material (leaves grass clippings etc) and don't let it dry out and it will be fine.

The amount of formic acid created from the saw dust from a sheet of MDF in a compost bin is about the same amount created from two cans of Diet Coke or Pepsi Max at 30 deg C and people actually drink that stuff!!

David

[Brady Watson]

There are a lot of different brands and types of MDF out there...clearly. For instance Trupan Ultralight MDF is made out of Radiata Pine, where 'standard' big box store MDF isn't.

Sierra Pine makes a great moisture-resistant MDF, called Medex. You can check out the info here - and note that they are coining the phrase SDF - or Sustainable Design Fiberboard. You may also want to take a peak at the MSDS (http://www.sierrapine.com/Media/MSDS-SierraPine-MDF-NAF.pdf).

Personally, unless the dust or chips came from real wood with visible grain, it isn't going anywhere in the compost heap or even flower beds. I don't want to be eating, drinking or showering in any by products that seeped into my soil or well. It would be nice to compost the stuff FOR SURE...but until there are regulations or a more steady supply of the SDF stuff, scraps will unfortunately be going in the trash.

-B

[Bob Eustace]

Thanks David - we are indeed on acreage and do have heaps of compost. After the Black Saturday fires we also got tons of wood chip from all the cleaning up. Still getting them today 3 years down the track. Please oh please come and stay if you are ever in Melbourne - wife could get pregnant though as its a very romatic house almost all timber. And yes it snows up here! Never did that when I lived in Cromer/Wheeler Heights!!!!! Three bots down here an hour away from each other.

[Bob Eustace]

Thanks Brady. The trend here is to go for Enviro Grade. Supposed to have minimal light ends releasing. However yiou can no longer cut MDF on a building site unless in a room with dust ectraction. Personally I hate the stuff but if you need to eat you gotta cut it!

[davidp]

Hi Brady,

In Oz we basically only have two brands of MDF Laminex and Austral. There are several other smaller companies but they are usually only found in their local area. Both Austral and Laminex MDF is mostly Radiata Pine with various amount of eucalyptus hardwoods as well. The Laminex MDF is all PEFC & FSC certified and is what is known as E0 ie it does not give off any VOC's even when cut. The MR has a lower formaldehyde content and a slightly higher resin content than standard MDF. In both cases the amount of Formaldehyde is minimal and as I said earlier it is certainly less than the amount that can by synthesised from a couple of cans of Diet Coke or Pepsi Max.

The problem with MDF is not the chemical content but the particulate size when it has been machined. A lot of the dust particles are small enough to pass through most of the "hobby" dust collectors, and most certainly the bag type collector filters. However the particles are large enough to get caught in the airways and cause cancers and other lung diseases. That is why it is important, even with good dust collection, to wear a mask.

Bob,

I know Kinglake, it is a beautiful part of the world. I am trying to convince "she who must be obeyed" that we should visit the Vic High Country again sooner rather than later and there is no fear that we would become too amorous. After almost 40 years, three kids and two grandkids that is not going to happen soon and not especially if I dragged her off on some vague excuse just to visit a shopbotter!!!


Regards,
David.
Sydney

[Bob Eustace]

Wonderfully informative post David - thank. You know more about the subject than my customer. Show the wife this pic on a stinking hot humid day in Dee Why and she will want to come down SAP!