A new testing procedure developed at the State Hygienic Laboratory can lower costs and simplify methods to analyze water for antibiotics, pharmaceuticals and other chemicals.

John Vargo, Ph.D.

John Vargo, Ph.D., program manager for the lab in Coralville, and his team developed the new procedures and utilized them in a recent study, “Determination of Emerging Contaminants in Iowa Surface Water.”

The Hygienic Lab is one of the few state laboratories in the United States to test for these chemicals. The new testing procedure is more precise, faster and less expensive than conventional methods.

Though they are typically very low in concentration, the chemical contaminants are a source for the potential ecological and cumulative effects on aquatic organisms found in surface water, including the possibility of contributing to antibiotic resistance, Vargo said.

The chemicals are considered emerging contaminants because they are newly recognized for their potential threat to the health of people and to the environment. Amphibians, for example, are particularly sensitive to endocrine-disrupting chemicals that can interfere with the production of hormones. The EPA does not mandate testing or set exposure levels for most of these contaminants.

Vargo said while the tiny quantities of the compounds might not have an immediate effect -- someone would have to drink an Olympic-sized pool of water containing caffeine at the low levels that are often found in drinking water to get the same amount of caffeine as in one serving of coffee from Starbucks -- whether or not these drugs have a cumulative effect is under study.

There is increased interest in testing for these chemicals, but existing analytical methods have tended to be expensive and labor-intensive.

"We recognized there was a need to simplify the procedure," Vargo said of the methods.

About 10 years ago, the lab developed a generic solid-phase extraction method, in which compounds are concentrated and isolated for analysis. More recently, Vargo developed a procedure that directly injects and analyzes the water sample, by-passing the time-consuming and labor-extensive extraction process.

"We're taking the water and pretty much analyzing it directly," he said, adding that in doing so, testing costs can substantially decrease.

The direct aqueous injection procedure, or DAI, eliminates issues with extraction efficiency and lessens the staff time needed for the tests. This cuts costs and also decreases expenses because extraction solvents are not needed.

The study is based on information derived from water samples gathered from the Cedar and Iowa rivers. Limnologists from the Hygienic Lab collected these samples during January 2014.

Vargo is presenting some of the findings at the American Society for Mass Spectrometry Annual Conference in Baltimore this month.

"The emphasis is on the methodology and comparing how well the [DAI and solid-phase extraction] procedures work," he said. The data itself is of interest because it quantifies the levels of caffeine, acetaminophen and more than a dozen other compounds found in the water.

Water samples from both rivers, taken upstream and downstream from Iowa City and Cedar Rapids, detected the presence of carbamazepine, an anti-seizure drug that was in noticeably higher quantities downstream from Iowa City.

Vargo noted that the chemicals not only enter the water through improper disposal of medications, such as flushing them, but through urine and feces, as the body does not completely metabolize the products.

Another source, particularly for antibiotics, comes from the livestock industry, he said.

In one of the more well-known cases, the lab tested samples for the Chicago Tribune, which investigated several issues, including whether or not chemicals were present in water from public sources, including drinking fountains at schools and bottled water.

More recently, Vargo said the lab has been working with the Iowa Department of Natural Resources on a two-year study to test surface water for the presence of chemicals at numerous sites across the state. It is also joining with Purdue University to study the effectiveness of wastewater treatment plants in the removal of these chemicals from wastewater influent.

In addition to the June conference in Baltimore, Vargo said the results of the Iowa study will be presented in September at EmCon 2014, an international meeting on emerging contaminants that will be held in Iowa City.