Many countries, including the US, have a comprehensive set of guidelines to make sure that the harmful chemicals in your water, and your overall water quality, are being examined and regulated.

In the US, the EPA has legally enforceable standards for all different types of pollutants in your drinking water, as well as secondary concerns that may cause skin irritation or affect your hair. Your local water supplier should produce a new Consumer Confidence Report each year, and the EPA has a public database designed to let you easily look up the most recent tap water report for your area. You can read the report and see if there are any worrisome pollutant levels in your water, but you can also rest safe in the knowledge that if any water contaminants are over their legal limit, your community will certainly be notified.

If you're especially worried about lead, one easy way to mitigate that risk is to simply run the tap water a few minutes before using it. The most dangerous amounts of lead accumulate when the water has been sitting in your home's pipes overnight, so if you flush that water out of the lines, you'll be in better shape.

Lead and chlorine in drinking water

Even if your water smells and tastes fine, that doesn't mean your tap water is free of harmful chemicals. Water pollutants fall into different categories, but the ones of primary concern in your shower water are toxic metals, chlorine (used as a disinfectant) and the byproducts that chlorine creates with other chemicals in the water. Any of these can put a major crimp in your shower experience.

The main toxic metals that often hide in water are arsenic, lead, cadmium and mercury, all of which made the World Health Organization's Top 10 list of "chemicals of major health concern."

Lead is often deemed the biggest contaminant offender, even if your water supply is pure, water slowly corrodes the lead in home plumbing systems, and the toxic metal seeps into the water. Children are at a particularly high risk for harsh chemicals and have been reported to absorb up to 50% of their lead through drinking water. Even at relatively low levels, the WHO reports, lead exposure can cause irreversible neurological issues. This is why water quality must always be a consideration.

Another main issue is connected to the chlorine that's used as a disinfectant in our drinking water. The major health concern is actually the byproducts created when chlorine reacts with natural organic matter in the water, creating harmful chemicals called THMs. You've probably heard of chloroform, which is just one common THM, and high levels of THMs act as carcinogens.

One study found that people absorbed more THMs from a 10-minute hot shower than from drinking a liter of water, so if you're concerned about this, a shower filtration system that actively removes chlorine can be helpful.