Oil-based paint is commonly made up of linseed oil with pigments suspended within the drying oil. Some oil paints will have different consistencies depending on the type you go for. Some oil-based paints will have an addition of solvents such as turpentine and varnish, these will make the paint have a slightly more glossy effect.
Oil-based paint is not only used for artists' purposes but can also be used on interior and exterior decoration. Due to its hard-wearing nature and brightness of colors, you may see it used on large metal or wood structures such as buildings or bridges.
Oil-based paint is considered hazardous waste and needs to be disposed of correctly. In many cities disposing of most paints is deemed illegal and will need to be disposed of responsibly. Oil-based paint can also last up to 15 years if sealed so if possible try to save the paint for later touch-ups rather than throwing it away.
As there are few ways to dispose of this hazardous waste, in most cases it would be easier to attempt to donate the paint rather than throwing it out. You can donate the paint by asking friends or neighbors, or even in some circumstances, you can ask local facilities such as schools or even theaters will be happy to take it.
If you can't find anywhere to donate the paint you will need to make sure that the paint is fully dried out before it is thrown in the garbage. To dry out the paint you will want to either leave to paint tin open in a well-ventilated area (as long as the leftover paint is only a maximum of 1 inch deep), this will take a few weeks to fully dry up. If you have a larger amount of paint you can try separating the paint into different tins/bowls and added sawdust or cat litter to speed up the drying process.
After drying the paint it can be added to the normal trash. Please remember that this is not an eco-friendly way of disposing of the paint and if possible please try to donate the paint.