chemical-free blackout fabric

[momster]

I'm making curtains for all the bedrooms and trying to avoid poly fabrics because they often have more chemicals in them. Would love organic cotton, but don't know if I can afford.

I need to make them blackout curtains though. I have a new baby and I'm having a hard time going back to sleep at night because of the streetlights.  Is there some type of non-poly fabric that would blackout the light?

Thanks.

[here we are]

Deleted
Edited by here we are - 11/9/12 at 3:00pm

[here we are]

Deleted
Edited by here we are - 11/9/12 at 2:59pm