Don't throw turps away after you've cleaned your brushes in it. Simply let it stand and the sediment will fall to the bottom. You can then pour off the clean turps and reuse it.
Paint and chemicals can be hazardous. Try to buy only enough for the job at hand. If you must store them, keep them well out of the reach of children in a secure place. Try to store paint in a smaller container so that the amount of air in the can is minimised.
Like all chemicals, paints, strippers and other products should be disposed of carefully - that means not poured down drains or into the garden.
Water based or acrylic paints can be safely disposed of in household rubbish if they are dry. Take off the lids and let them dry out thoroughly before putting them in the bin.
Oil based paints are flammable and should be put out on special rubbish collection days. If you have any doubt about how to dispose of them safely, ring your local council.
Strippers and other chemicals should be disposed of in the same way as oil based paints.