William van der Schalie and his team at an Army research laboratory in Maryland have developed a unique and innovative way to detect chemical contamination of drinking water supplies and keep millions of Americans safe in large metropolitan areas including San Francisco, New York City and Washington.
To fight this serious public health threat, they have joined forces with an uncommon ally: fish.
In a process that combines both science and the wonders of nature, the researchers are using bluegill as indicators of water toxicity levels. Originally developed for use by the military, the system has been commercialized and is now being used to protect some large city water supplies from dangerous pollutants and the possibility of foul play.
“It’s a novel approach that departs from looking at each possible contaminant, but rather uses a screening technology for raw water sources,” said Robert Ryczak of the U.S. Army Public Health Command. “There are only 132 chemicals that are regulated nationally, but there are over 900 water-borne toxins globally. This screening doesn’t care what the chemicals are, it detects contaminants.”
There are many ways to test for toxicants, but none provide the unique capability of bluegills for rapidly identifying emerging water toxicity threats.
The creative sentinel system monitors fish behavior using pairs of electrodes mounted above and below each of eight bluegills that are confined to a chamber submerged in a body of water.
As the fish move in the chamber and ventilate their gills, muscle contractions generate electrical signals in the water that are monitored by a computer. Scientists look at fish behavior, including ventilation rate, the strength of ventilation, gill purge (cough) rate and body movement rate.
The monitoring system was developed by the Environmental Sentinel Biomonitor (ESB) team headed by van der Schalie. The team, part of the Army Center for Environmental Health Research at Fort Detrick in Maryland, likens its unusual monitoring system to the canary in the coal mine.
In addition to San Francisco, New York City and Washington, the fish alarm system has been used to detect harmful water quality conditions in tributaries to the Chesapeake Bay, at Cherry Point, N.C., and by the U.S. Environmental Protection Agency in Cincinnati, as well as other locations.
This monitoring system is part of an ongoing research project, with a cell-based toxicity sensor now in the works for evaluating Army field water supplies.
Instead of using fish, the Army team is studying which biological systems most react in a way a human would when exposed to contaminants. The goal is to have this technology stored on a credit card-sized device that can be carried by military members in the field so they can easily determine which raw water sources are safe to drink.
The success of this ongoing research could have major implications. Toxic industrial chemicals are a potential threat to field drinking water supplies, but capabilities for rapid field testing of water are limited to relatively few chemicals. This new system could significantly augment current detection methods.
Such challenges are nothing new to van der Schalie, who has researched aquatic toxicity throughout his 31-year career working for the Army and the Environmental Protection Agency (EPA).
“Bill was involved with basic biomonitoring research as a graduate student at Virginia Tech years ago. He took the research approach into a very useful application that’s made a tremendous difference for the military, but also for municipalities,” said Maurice Zeeman, a senior scientist at the EPA.
Hank Gardner, a professor at Colorado State University said van der Schalie has been “the guiding star on scientifically sound research that is relevant to the public and furthers environmental health technology.”
“Science comes first for him, but intimately coupled with sound science is useful science. He always asks, ‘Does it benefit the public at large?’” said Gardner.
Van der Schalie credits the Army’s Small Business Innovation Research program for making the sentinel system possible. His team has been matched with small business partners that have leveraged knowledge and expertise toward different stages of the team’s projects.
Lt. Colonel Andrea Stahl attributes the success of van der Schalie’s team to a long-term approach.
“They have a commitment to addressing these issues over time, and their persistence has made a tremendous difference. Much of their success is due to the leadership of Dr. van der Schalie,” said Stahl. “He is the model federal employee. He’s incredibly hard working, is organized and plans well across his team. You couldn’t ask for a better employee.”