Caffeine and a drug used to regulate blood sugar levels for people with Type 2 diabetes wash down the drain every day to become some of the most common unregulated contaminants in Iowa’s public drinking water, an IowaWatch investigation revealed.

The presence of these contaminants is so miniscule that what a drinking water consumer takes in is fairly minimal. But federal government officials are concerned about them because the risks of chronic ingestion of these contaminants are unclear, the result of a lack of research to determine potential health risks for humans.

Prescription drugs and caffeine contaminate rivers and streams treated to become drinking water. Many of these contaminants affect the human endocrine system, which produces hormones that regulate metabolism, growth and development, among other functions.

The East River Station in Davenport, Iowa, pushes water back into the Mississippi River after being treated. Water in the pool on the right is to be mixed with treated water before going back into the river, while water in the pool on the left is to continue through the final stages of treatment.
The East River Station in Davenport, Iowa, pushes water back into the Mississippi River after being treated. Water in the pool on the right is to be mixed with treated water before going back into the river, while water in the pool on the left is to continue through the final stages of treatment. Credit: Brittany Robb/IowaWatch

Chemicals that affect the endocrine system exist in nature, but show up prominently in man-made products such as pharmaceuticals, plastics, detergents and cosmetics that people dump down a drain. These compounds commonly are referred to as emerging contaminants.

“Iowa is in a water quality crisis,” Des Moines Water Works communication coordinator Laura Sarcone said. She cited that facility’s increased use of an expensive nitrogen removal process and a record number of impaired waters as determined by the Iowa Department of Natural Resources as well as a growing concern about the impact of emerging contaminants.

Some of the cities in Iowa most likely to be exposed to emerging contaminants include Des Moines, Davenport, Cedar Rapids, Sioux City, Iowa City and Keokuk. All use a high proportion of surface water, making them more susceptible to pharmaceuticals and endocrine-disrupting chemicals than cities that rely more on underground aquifers for drinking water.

A new national study conducted by the Harvard T. H. Chan School of Public Health analyzed data from the third round of unregulated contaminant monitoring and concluded that millions of Americans may be drinking water with unsafe levels of polyfluoroalkyl and perfluoroalkyl substances. The contaminants come from industrial site, military bases with firefighting training and wastewater treatment plants.

A little less than half of Iowa’s residents get drinking water from systems that use surface water or a combination of surface and groundwater. They are among the nine of 10 Iowans who use public water systems, with the remainder using private well services.

Eight percent of Iowa’s public water systems use surface water, sometimes mixed with water from other sources, but are in the most heavily populated areas.

“Everything we use has the potential to become an environmental contaminant,” Dana Kolpin, a research hydrologist with the U.S. Geological Survey, said. “We use it, we excrete it, we wash it down the drain.”

Guide: CEC -- Contaminants of Emerging Concern
Guide: CEC — Contaminants of Emerging Concern Credit: U.S. Environmental Protection Agency graphic
Guide: CEC — Contaminants of Emerging Concern Credit: U.S. Environmental Protection Agency graphic

Caffeine ends up in water from a number of sources, not limited to coffee and soft drinks. Soap, shampoo and even pantyhose can be caffeinated and it’s this level of dependence on caffeine that makes it such a prevalent contaminant.

Although water from our drains and toilets goes through a wastewater treatment plant, emerging contaminants can survive wastewater treatment and end up in surface water, which then can become source drinking water for communities downstream.

So many potential contaminants to monitor from an array of sources exist that trying to understand each one can be overwhelming for researchers and treatment facilities. It is hard to narrow down what to focus on given the low-priority level of emerging contaminants for most facilities.

Tim Wilkey, superintendent of the Iowa City Wastewater Treatment plant, describes that plant’s treatment process to IowaWatch on June 24, 2016.
Tim Wilkey, superintendent of the Iowa City Wastewater Treatment plant, describes that plant’s treatment process to IowaWatch on June 24, 2016. Credit: Brittany Robb/IowaWatch

Tim Wilkey, superintendent of the Iowa City wastewater treatment plant, said pharmaceuticals and caffeine can pass through the treatment process but only at minute levels. Treated water from Iowa City’s plant washes into the Iowa River, which feeds into the Mississippi River and continues downstream.

Some wastewater and drinking water treatment plants use a treatment process called activated carbon, which is effective in preventing emerging contaminants from permeating drinking water supplies. This treatment process uses carbon to attract unwanted organic compounds such as caffeine through adsorption, leaching those compounds out of the finished water. Activated carbon also is used in air filtration and other purification applications. (see sidebar)

Activated Carbon Treatment Process:

Activated carbon is a porous substance that attracts organic chemicals through a process called adsorption. Adsorption varies from absorption because adsorption uses only a product’s surface area to take in material, while absorption uses the whole of the product.

A carbonaceous substance – often charcoal – is burned without oxygen to create a substance – called “char” – that is chemically treated to develop the pores of the finished product. The network of pores makes for a large surface area for the product to take in organic material. One gram of activated carbon has a surface area that can range from 500 square meters to 1,500 square meters, or 5,382 square feet to 16,146 square feet.

Activated carbon is a cost-effective way for air filtration and water treatment to remove minute levels of organic contaminants. Activated carbon works as a purifying measure through the process of adsorption.

Coal and coke can also be used to create the initial char material and are called activated coal and activated coke, respectively.

Sources: General Carbon Corp., New World Encyclopedia

– By Brittany Robb, IowaWatch

According to findings from the 2013 Survey of Iowa Groundwater, the highest level of acetaminophen found in one sample was 826 ng/L (parts per trillion).

“For perspective, it would take almost 200,000 cups of untreated well water to equal the dose of acetaminophen recommended for infants,” the report said.


The Environmental Protection Agency does not require removal of emerging contaminants from drinking water. To better understand these lesser known contaminants, the EPA developed the Unregulated Contaminant Monitoring Rule, a program designed to monitor and collect data for contaminants suspected to be in drinking water in order to determine whether or not to regulate them in the future.

Public drinking water source testing began at the state level in 1988 and became a national program following the Safe Drinking Water Act amendment of 1996. The first list of contaminants to be monitored nationally was published in 1999 and monitoring ran from 2001 through 2003. The third round of monitoring was the first to include emerging contaminants.

Not all contaminants in the program are considered emerging. Naturally occurring compounds like cobalt and testosterone were included in the third cycle, which ran from 2013 through 2015. Some of the monitored compounds considered to be emerging contaminants were perfluorooctanesulfonic acid – an ingredient in Scotchgard – and perfluoroheptanoic acid – a grease-proof substance used on food packaging.

No more than 30 contaminants can be monitored over a span of five years in the program, which Susan Glassmeyer, an EPA research chemist, said makes selecting which contaminants to monitor an added challenge.

“We only get to monitor 30 at a time so we don’t want to waste one of those slots,” Glassmeyer said in a June 29 EPA webinar.

The contaminants for the fourth round of monitoring have been chosen and include 10 cyanotoxin compounds – produced by blue-green algae – and eight pesticides.

These contaminants are monitored in all municipal supplies serving more than 10,000 people and select smaller systems. In Iowa, 58 public water systems participated in the last round of unregulated contaminant monitoring. Monitoring data is processed by certified labs – including the Iowa State Hygienic Labs in Coralville and Ankeny – and recorded with the EPA.

The final stage of drinking water treatment at the East River Station in Davenport, Iowa, involves pumping the finished product out to service areas. This treatment plant serves Davenport and Bettendorf, Iowa, consumers.
The final stage of drinking water treatment at the East River Station in Davenport, Iowa, involves pumping the finished product out to service areas. This treatment plant serves Davenport and Bettendorf, Iowa, consumers. Credit: Brittany Robb/IowaWatch

Jeff Mitchell, a lab supervisor with Des Moines Water Works, said concern about pharmaceuticals and other emerging contaminants began in the last 10 to 15 years.

“We’re always trying to stay ahead of the emerging contaminants, but money does influence that ability,” he said. The EPA pays for testing systems serving a population under 10,000 for the unregulated contaminant monitoring rule, but for systems over 10,000 the cost ranges from $50 to $470 per sample, per testing method, on average. The EPA estimates the average annual cost to each of these large systems over the five-year rule period to be less than $2,381.

Des Moines Water Works operates six systems that participate in testing for the program and most often saw levels of contamination below or equal to preliminary standards set in the monitoring rule.

Monitoring, however, does not equal treatment.

Medication disposal kiosks

Eight Walgreens locations in Iowa will add medication disposal kiosks by
the end of August, with an additional 500 at other nationwide locations.
Walgreens officials say the program is critical to reducing prescription
drug abuse, but reducing the amount of medications being improperly
disposed of will turn out to be an added benefit.

Chuck Pietscher, superintendent of the Keokuk Water Pollution Control Plant, said his plant does not have a specific treatment process to combat pharmaceuticals or other emerging contaminant endocrine disruptors.

“We can find anything anywhere anymore but we don’t know what it all means,” Pietscher said. “We don’t treat for those contaminants because we aren’t even sure which ones need to be treated for.”

That sentiment of a lack of information about emerging contaminants resounds among water quality specialists like Kolpin and treatment plant officials like Pietscher. While more testing will aid in identifying emerging contaminants, Kolpin said a seemingly endless list of compounds in the chemical universe could end up in drinking water.

“There’s so much going on with drinking water that it’s hard to point at one thing and just start,” Kolpin said. “It’s an ongoing learning process. As we find more in our drinking water, we will have to come up with more and more solutions to those problems.”

Six percent of Iowa’s public water systems violated standard health-based regulations in 2015, according to the DNR’s annual compliance report released in July. About 200,000 of the 2.9 million Iowans served by public water supplies were exposed to some type of health-based violation.

Unlike the emerging contaminants, the contaminants in the DNR report are regulated by the EPA and proved to have some level of health risks if ingested.

While there are no known health risks for humans ingesting emerging contaminants in water, research has shown some emerging contaminants have negative impacts on aquatic life.

Fourmile Creek runs through central Iowa and was tested at various points by Kolpin’s team. The team found that downstream from metro areas, including Ankeny, aquatic creatures responded differently to predators than those upstream. Minnow larvae in particular were found to have been exposed to a range of antidepressants such as bupropion and desvenlafaxine, and ended up responding slower to predators.

While the exposure itself did not directly kill the hatched minnows, Kolpin said the slower response time made them more susceptible to predators, thereby decreasing their survival.


Measures to clean up Iowa’s waterways garnered attention in the last state legislative session. One proposal involved allocating funds from the state’s sales tax for water quality measures, but opponents argued the move would hinder public school construction and improvement projects, which currently receive that funding. Four bills failed in the Legislature, but Gov. Terry Branstad said it doesn’t mean they are dead forever.

“When you have something that is big and bold and is a big change and expensive, it’s not unusual that it might take more than one session,” Branstad said in an interview with IowaWatch. “But there’s a clear understanding that there’s a need for a long-term reliable source for funding for water quality.”

Impaired Waters:

The Iowa Department of Natural Resources is required to submit a survey of Iowa bodies of water to the Environmental Protection Agency every two years. These bodies of water can have a variety of designated uses, from recreation to drinking water or an aquatic life habitat. Each body of water is categorized in one of five ways:

  • It meets its designated need.
  • Some designated uses are met, but there is insufficient data to determine if all are met.
  • More information is needed.
  • It is impaired, but a water quality improvement plan has already been written.
  • It is impaired and has no improvement plan written.

A waterbody is considered impaired until the water quality improves and it passes an assessment to show that improvement.

If one portion of a watershed is deemed impaired – say one portion of the Des Moines River – it does not mean the entire watershed is impaired. Improvements to the overall watershed can, however, have a positive effect on impaired portions of the watershed.

According to the DNR, the majority of impairments to waters in Iowa are considered minor to moderate. Out of 2,567 bodies of water analyzed in 2014, 765 were considered impaired. Seven met all designated uses while 1,455 had insufficient data to determine whether any designated uses are met.

Sources: Iowa Department of Natural Resources, IowaWatch interview with DNR environmental specialist John Olson

– By Brittany Robb, IowaWatch

None of the failed measures targeted emerging contaminants, but improving Iowa’s water quality needs a solution, according to many conservation groups as well as members of the state legislature. One of the failed bills would have directed funds toward improving more than  700 impaired waters in the state (see sidebar). A proposal to raise taxes garnered hesitation from both Republicans and Democrats in the Legislature.

One measure to increase the state sales tax by 3/8 of a cent would have allocated the additional revenue to protect and enhance water quality and natural areas in the state including parks, trails and fish and wildlife habitats, and conserving agricultural soils.

Branstad told a crowd in Storm Lake on Aug. 2 that he stands by his plan to split state sales tax funding between school improvements and water quality projects with the deadline of 2029. The next day in Anamosa he said neither the Iowa House nor Senate could support a tax increase in order to fund water quality projects.

Kolpin said the U.S. Geological Survey and EPA research showing negative health effects in aquatic life is enough of a reason to investigate if humans could be at risk as well.

“It certainly raises the question that if it’s happening to animals it at least deserves more research to see if there is a risk for us or not,” Kolpin said. “Certainly with pharmaceuticals you can’t deny there are benefits, but do we need to do better in takeback programs or have greener pharmaceuticals that break down quicker?”

One Iowa public water system is funding contamination prevention through environmental grants. Both the East River Station treatment plant for the Davenport area and the Clinton water treatment plant are owned and operated by Iowa American Water, a subsidiary of American Water. The parent company, based in New Jersey, provides drinking water and wastewater treatment services in 47 states and Ontario, Canada.

American Water provides environmental grants to projects in their service areas with a focus on improving and restoring watersheds, surface and groundwater resources. In 2015, Iowa American Water funded a $1,000 grant to Gateway Impact Coalition – a Clinton County-based organization focused on increasing community collaboration and reducing substance abuse – to put pharmaceutical drop boxes in police departments in Clinton County for people to drop off their pharmaceuticals for proper disposal.

Rich Oswald, superintendent of the East River Station drinking water treatment plant in Davenport, Iowa, discusses the plant’s treatment process in an IowaWatch interview on July 12, 2016.
Rich Oswald, superintendent of the East River Station drinking water treatment plant in Davenport, Iowa, discusses the plant’s treatment process in an IowaWatch interview on July 12, 2016. Credit: Brittany Robb/IowaWatch

“A lot of people flush medications down the toilet or discard of them not the right way, so we try to find a way to make sure those are disposed of properly,” Rich Oswald, superintendent of the East River Station treatment plant in Davenport, said in an IowaWatch interview.

Kolpin said takeback programs like the one in Clinton County could prevent some pharmaceuticals from going down the drain but that it will take more to prevent pharmaceuticals from ending up in drinking water.

Instead of focusing on wastewater and drinking water treatment down the line, he said, people should focus on the source: reducing what he viewed as overuse of caffeine and adjusting the way doctors prescribe medications in order to prevent excess medication from piling up in home medicine cabinets.

Kolpin said future research into these contaminants will be important, especially given what scientists know about their effects on aquatic life.

“People aren’t having massive effects but there could be some chronic level multi-generational thing that we just don’t know is happening yet,” he said. “In my mind there is good news, but it’s cautionary news.”


This IowaWatch story was republished by The Iowa City Press-Citizen, Des Moines Register, Sioux City Journal, Quad-City Times, the Hawk Eye (Burlington, IA), Mason City Globe Gazette and under IowaWatch’s mission of sharing stories with media partners.

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