In late January 2017, the Department of Environmental Quality released a study of pockets of groundwater outside of Medford and Central Point, Oregon. Among the 107 wells tested, 21 percent had higher levels of nitrates, while four percent had higher than recommended health levels. Twenty-two percent of the wells contained arsenic and six percent had unhealthy levels. While the findings were lower than expected, the presence of nitrates and arsenic in drinking water raises a red flag for local residents.
According to the Oregon Health Authority, nitrates, which are found in fertilizers and other agricultural products, can cause chronic and acute effects particularly in infants. Nitrates in drinking water may cause blue baby syndrome, which can lead to death. Exposure to arsenic “can lead to skin lesions, damage to the circulatory and nervous systems and can cause some forms of cancer.”
The study by the DEQ establishes a baseline that can be used for future testing. There is no plans for future testing, nor is there previous data to establish trends. The study also does not consider sources of the contamination. The study area included the Rogue River from Shady Cove to Grants Pass and along the Bear Creek Basin from Central Point to southeast of Ashland.
Among the other DEQ findings were the following:
- At least one pesticide or chemical resulting from the breakdown of a pesticide was detected in 38 percent of the wells –though all of the readings were well below the level considered a threat to human health.
- Coliform bacteria were detected in 43 percent of wells tested, which may indicate contamination of the aquifer or problems with individual well construction or sealing.
In 2001, the Environmental Protection Agency released a new standard for arsenic in public drinking water supplies. The acceptable level went from 50 parts per billion to 10 parts per billion. The goal of the EPA is zero parts per billion, a level at which no adverse health effects are expected.
Other areas of the country are testing for arsenic in drinking water, including Iowa. Tests conducted in the summer of 2016 on wells across the state found no wells with the maximum EPA public standard, but “a handful showed detectible levels of arsenic at two or three parts per billion.”
Concerns in Iowa came about in the early 2000s when Cerro Gordo County found arsenic in the public water supply at rates of 540 pars per billion.
From May 2006 through December 2008, the second phase of the Iowa Statewide Rural Well Water Survey by the University of Iowa Center for Health Effects of Environmental Contamination “found arsenic in 48 percent of the 473 private drinking water wells sampled across 89 counties. Eight percent of wells had levels of arsenic above the EPA’s standard for public water supplies.”
Cerro Gordo County in Iowa tested more than 50 private wells from July 2011 to June 2014 for arsenic. Each well was tested twice a year.
“Half of the county’s wells showed detectible levels of arsenic. One-third showed unsafe levels above the EPA drinking water standard.”
Pete Weyer, interim director of the University of Iowa Center for Health Effects of Environmental Contamination, stated, “Arsenic is highly toxic and it would be best not to have any arsenic in your water, not because it’s necessarily going to cause any health problems for you but just to be safe.”
Health experts in Missoula County Montana are encouraging private well owners to test their water. A study in Hunterdon County, New Jersey has found higher levels of arsenic in 16 percent of wells while California recently reported that nearly 300 public water systems across the state are out of compliance with violations including unsafe levels of arsenic and nitrates.
Arsenic is odorless and tasteless, so unless tests are run, people will not be aware that it is in their drinking water.
CETAC offers sample introduction accessories that improve the transport efficiency of a liquid sample to an ICP-AES, leading to enhanced analyte sensitivity (such as for arsenic) by the host detection system (the ICP-AES).
The two CETAC accessories that improve sample transport efficiency to an ICP-AES are:
- The U5000AT+ Ultrasonic Nebulizer
- The HGX-200 Hydride Generator
With the U5000AT+ Ultrasonic Nebulizer, detection limits for arsenic with ICP-AES are in the range of 0.1 to 1.0 ppb, with 0.5ppb a typical limit.
With the HGX-200, detection limits for arsenic with ICP-AES are usually lower, with detection limits of 0.1ppb or less.
For more information on these products, please contact us.
