Cleaning supplies tend to grow in quantity under sinks and in pantries. Perhaps you forgot you already had furniture polish, or you wanted to try out a new stove cleaner. For whatever reason, you may end up with products in cans and bottles that you will never use.

If you hire a new janitorial service to keep your home clean, they will often bring their own cleaning supplies, and your stock of detergents and cleansers will simply collect dust. When it's time to de-clutter your cleaning supply area, follow these rules:

Find ways to get more use from products

If the cleaning products are still good, give them to a friend, family member or local nonprofit that can use the extra supplies. Just be sure products are in their original containers with all of the required use and care information intact.

If you have a large number of cleaning products, consider placing an ad on Craigslist or Freecycle, or in your local paper, offering the items for free. Local homeless shelters, humane societies and churches may also be happy with donations of extra supplies.

Know the shelf life and safety precautions of products to be discarded

Cleaning supplies don't last forever, as special formulations may break down, while other active ingredients lose their effectiveness. For instance, bleach is good for 3 to 6 months, opened laundry detergent is good for around 6 months, and window cleaner is stable for up to 2 years.

If you know your cleaners are past their prime, it's time to let them go. But be careful to read all of the safety precautions for any product you toss. Some products--like bleach and ammonia--will create toxic fumes if you pour them down the drain together.

Water-soluble products are normally safe to pour away

Pour most water-soluble cleaning products down your drain, using plenty of water to flush the drain as you do so. Laundry detergents, bathroom disinfectants and other similar products are designed to be used in your sink and washer and then drained away, so they won't hurt pipes or septic systems or other municipal waste management systems.

The exception would be powdered or very viscous cleaners that might clog your pipes if poured in all at once. Dilute these cleaning products with plenty of water prior to pouring them down the drain.

Oil-based, crystal and other cleaners should be safely disposed of as directed on the package. Many communities hold special collection days where they allow you to safely dispose of paint, thinners, de-greasers and other hazardous materials. Check with your city or county to learn about these dates.

Don't forget to recycle bottles, bins, aerosol cans and other containers. Your local janitorial service may know where you can do so, or you can check with your local officials to learn about recycling centers near you.