TDS Meters are often promoted as a simple way to determine the quality of your drinking water, but a low reading should not be used as an indicator of contaminant-free water. TDS stands for “total dissolved solids” which are all the organic and inorganic substances in a water supply. Many of these solids are harmful (environmental run-off, nitrates from pesticides and fertilizers) and can be reduced with a good water filter, but others are essential for health and good tasting water (calcium, magnesium and potassium).
If you are considering a TDS Meter to measure water quality, there are two important things to keep in mind.
1. TDS Meters Don't Measure Lead
Lead, when found in water has shown to have negative health implications, can’t be measured specifically by TDS meters. The Water Quality Association (WQA) calls out the misconceptions about these meters and states that lead concentration is too small to be detected by TDS meters.
Without getting too technical, lead concentration is found at the parts per billion (ppb) level. TDS meters only measure at the parts per million (ppm) level, so if there is lead present, these devices can’t specifically detect it. If you think lead problems are specific to only certain cities, it’s important to know that recent news stories have called lead in our water systems a national problem.
TDS meters are only able to measure the presence of all dissolved solids, so any individual solid, like lead, can’t be detected on its own.
2. "000" Meter Readings are Misleading
Not all dissolved solids in water are bad for you, some are minerals essential for health and good tasting water. TDS Meters report on solids with a 3- or 4-digit number representing the parts per million. The World Health Organization (WHO) states that levels below 500 are completely safe. Anything below 300 is considered “excellent” and above 900 is considered “poor ”.
Some want you to believe that a 000 reading is best, but that’s part of the misconception. Minerals in water may provide clinically important portions of the recommended dietary intake. For example, even healthy beverages like milk and orange juice will have a TDS reading in the 200-250 ppm range. On the other hand, place a TDS meter in something you’d never drink, like acetone used in nail polish remover and paint thinner, and it will give you a 000 reading. A 000 reading may provide a false sense of security.
Understanding filtration and water measurements can help you make the right choices for you and your family. For cleaner, great tasting water straight from your tap, choose PUR Faucet Filtration Systems. PUR Faucet Filters are certified to remove 99% of lead and more contaminants than any other brand – while preserving what makes your water healthy and delicious.