Water Quality of Potential Concern in US Private Wells

[amyrose2712]

More than 20 percent of private domestic wells sampled nationwide contain at least one contaminant at levels of potential health concern, according to a study by the U.S. Geological Survey (USGS).

About 43 million people - or 15 percent of the Nation's population - use drinking water from private wells, which are not regulated by the Federal Safe Drinking Water Act.

USGS scientists sampled about 2,100 private wells in 48 states and found that the contaminants most frequently measured at concentrations of potential health concern were inorganic contaminants, including radon and arsenic. These contaminants are mostly derived from the natural geologic materials that make up the aquifers from which well water is drawn. Complete findings are available online.

(snip)

Other contaminants found in the private wells were man-made organics, including herbicides, insecticides, solvents, disinfection by-products, and gasoline chemicals. Few organic contaminants (7 out of 168) exceeded health benchmarks, and were found above health benchmarks in less than 1 percent of sampled wells. Organic contaminants were detected at lower concentrations in more than half (60 percent) of sampled wells, indicating that a variety of contaminant sources-including agricultural, residential, and industrial-can affect the quality of water from private wells. The study measured organic chemicals at very low concentrations-often well below human-health benchmarks-in order to assess occurrence and sources; detections do not necessarily indicate human-health concerns.

Contaminants found in private wells usually co-occurred with other contaminants as mixtures rather than alone, which can be a concern because the total combined toxicity of contaminant mixtures can be greater than that of any single contaminant. Mixtures of contaminants at relatively low concentrations were found in the majority of wells, but mixtures with multiple contaminants above health benchmarks were uncommon (about 4 percent). The USGS report identifies the need for continued research because relatively little is known about the potential health effects of most mixtures of contaminants, and the additive or synergistic effects on human health of mixtures of man-made chemicals at low levels are not well understood.

http://www.usgs.gov/newsroom/article.asp?ID=2173&from=rss

[ensho]

1. this is hugely important - I can see a new business of testing well water

long ago and far away well water was tested for hardness/softness. nowadays testing has to include all kinds of toxins including hormones and antibacterial stuff.

so scientific labs are needed to do the tests.

we are so far behind the curve its shameful.

[kestrel91316]

2. This is the logical outcome of our wasteful, polluting ways.

[amyrose2712]

3. Yeah...

I just thought I would post, so many people still think if they have a private well that the water is clean.

[RockaFowler]

4. We have a well

I wouldn't drink that water if you paid me. We use it strictly for irrigation.