Eleminating ordinary paint odours
Are you tired of the smell of paints and finishes? There are now several products on the market that you add to your paint and when it starts to dry on the wall, this chemically reacts with those molecules that cause the odour and stop those odours.
It works with many different products, including latex paint and oil based paints but doesn't work with a couple of things, so always read the label carefully before even buying it. Of course no paint manufacturer recommends using other manufacturer's additives in their product. You could void any warranty.
Some latex paints leave a stronger smell than usual, even after dry on the wall. This can sometimes be removed by "painting on" a thin mixture of water and baking soda, let it dry, then rinse it off. You will have to rince a couple of times because it tends to leave a chalky film. This is the same stuff that takes smells out of the refrigerator.
If you really need to cover up a smelly paint, use white shelac as it is the best odour shield available.
Can mixing silica sand into paint create a toxic gas?
One radio listener got a very disagreeable odour when he added silica sand to his paint to give it a texture for his walls. Chat on the web got him worried that it was some kind of a toxic reaction with the paint. I ran this by the Technical Services of AkzoNobel Paints and learned some very interesting things.
Silica sand, even silica dust, is often added to paints of all kinds without any reaction. Sand, in and of itself is inert. But occasionally there can be odours. Why?
Water based paints always contain an additive designed to protect against the growth of algae, bacteria and other micro-organisms. This generally protects the water in the paint from going stagnant as it sits and against normal every day yeast and other spores in the air that can get into the paint can as soon as it is opened.
If some silica sand had become contaminated, perhaps left open for some time, it is possible that this addition of micro-organisms might over challenge the paint additive and the micro-organisms take over in the can. The odour has been described as rotten eggs, to stagnant water, to a manure smell.
This can all be avoided by:
-using sand from a freshly opened package;
-sprinkling the sand over the paint as is commonly done for anti-skid use;
-if you want to mix the sand into paint, do it in limited batches that will be used that same day. This will avoid giving the micro-organisms time to grow.
As to the original question -- no there is no nasty chemical reaction between silica sand and any type of paint; in fact clean sterile silica is often used as a paint pigment.
Disposing of paint
Left over solvent based finishes should be sealed tightly and taken to the hazardous waste dump, although some paint stores will accept well sealed cans -- (well sealed means they don't leak and make a mess).
If you want to get rid of latex paint, you could always just leave the can open until it got hard, then throw it away in the regular garbage. To speed up this process you can buy a latex paint hardener, for solidifying waste paint quickly. Don't accidentally stir this stuff into your new gallon of paint!