If you own a private well that means you and you only are responsible for the safety of your water. Testing is the key to knowing what you are drinking. The largest concerns on private wells are nitrates, bacteria, and even pharmaceuticals. Nitrates (pesticides) are carcinogens (toxins) that have been linked to cancer. So as you can imagine drinking it is not a good idea! Bacteria as well can be dangerous as well and can lead to illness and even death if the amounts are large enough. As for the pharmaceuticals, these are new. It seems what we have been throwing away is coming back to haunt us. Anything disposed into the ground eventually can end of in our water systems. So the farmer down the road spraying his crops, and fertilizing his soil could potentially be poisoning your drinking water.
Remember that even if the results you find from testing show safe drinking water today, that may not be the case later. Well water conditions can change depending on several factors so it is vital that you test your water annually if you do not have a filtration system in place. Below is a link to show you all the potential contaminants that may be found in your private well. This information will definitely make you want to test your water! The goal is always to protect your family from unsafe environmental factors, and having safe drinking water is important to you and your family.
Information for this blog was gathered from the following links:
http://water.epa.gov/drink/info/well/upload/2003_06_03_privatewells_pdfs_household_wells.pdf
http://water.epa.gov/drink/info/well/health.cfm another great link on pesticides: http://waterquality.montana.edu/docs/homeowners/pesticides.shtmlwater