A simple way you can reduce the toxins in your environment is to switch to all-natural cleaning products. Many common household cleaning products contain toxins that may increase risk of cancer. According to the American Lung Association, VOCs (volatile organic compounds) in cleaning products can irritate your eyes or throat, cause headaches, and may cause cancer. They encourage everyone to read labels and avoid these harsh chemicals. Using natural cleaners, will leave your home smelling fresher, feel cleaner, and makes cleaning enjoyable if you don't have to breath in the chemical fumes.
There are also a number of online DIY recipes for household cleaners that are very effective. The Real Simple magazine has compiled a great list of DIY cleaners for everything in your house, from glass cleaner, to disinfectant, making your own cleaners with basic ingredients and essential oils will not only make your home feel fresher, but it will actually be much cheaper. See their list here.
If you prefer to buy cleaning products than make your own, there are a number of quality natural cleaners on the market now. From brands like Ecos, Method, Seventh Generation, Green Works, to Mrs Meyers, there are natural cleaners available for everything in your home.
If you have a favorite cleaning product, that contains chemicals that you really want to keep using, just be sure to open the windows to air out the space you're cleaning. The important part is not to let chemicals build up in the air you breath. Letting in fresh air is good to do frequently anyway - it helps radon escape, and freshens the air for a healthy home.