Water. Good, clean, pure water. What's really in it

Water is about the best thing you can drink. But it's rarely as simple as pure H2O.

This article details the findings of a water report of 28 million American households.

The study found 11 compounds in the water, albeit at low levels. Atrazine was the one that stood out most to me, mostly because I've heard of it before. Here is a smattering of the other 11 compounds:

• Carbamazepine, a mood-stabilising drug used to treat bipolar disorder, amongst other things

• Estrone, an oestrogen hormone secreted by the ovaries and blamed for causing gender-bending changes in fish

• Meprobamate, a tranquiliser widely used in psychiatric treatment

• Naproxen, a painkiller and anti-inflammatory linked to increases in asthma incidence

• Phenytoin, an anticonvulsant that has been used to treat epilepsy

Plus, there were a number of antibiotics.

If you're concerned about what comes out of your tap, you should consider adding a water purification system. My house came equipped with one under the kitchen sink, for drinking water only. It's an Amway brand and it seemingly does a good job, though I must say I've never done a chemical comparison test. I can taste the difference, however.

I replace the filter once a year, at a cost of about $65 a year. A little over a dollar a week for filtered water beats the cost of using bottled water, and it has a much smaller environmental impact.

Do you use a filter for your water? If so, what kind? Have you had your water tested? What chemical surprised you most?