Safe from Source to Sip
Something as simple as a drink of clean water is beyond the reach of more than a billion people around the world. Even in the U.S., safe drinking water is becoming less certain every year.
At the Center for Water and Health, researchers are trying to figure out how to bring basic safe water and sanitation to developing countries; at the same time, researchers at the Center study emerging contaminants that affect even developed countries. Some 2.4 billion people don't have access to improved sanitation, which increases the risk that their drinking water will become contaminated, notes Kellogg Schwab, a microbiologist who directs the Center.
In the U.S., part of the problem is underinvestment in maintaining the 500,000 miles of drinking water pipes in the country, as well as sewage lines. "They're underground," Schwab says. "Out of sight, out of mind. In the U.S., people take water and waste removal for granted." When sewage pipes leak, they risk contaminating groundwater and other water supplies. A leak in a water pipe could also lead to contamination, Schwab says.
“In the United States people take water and waste removal for granted. We assume high quality, potable drinking water will come out of the tap. We’re assured that if we drink the water, we’re not going to die in a couple of days. In many areas of the world, that’s not case.” —Kellogg Schwab
Aside from aging infrastructure, the U.S. and other industrialized countries face problems with emerging contaminants, such as endocrine disruptors, which can potentially cause harm in very small doses. Endocrine disruptors such as PCBs and DDT can cause health problems by interfering with normal hormonal functions. Some have been implicated in developmental problems in children, or in some types of cancer.
Schwab says that more work needs to be done in detecting emerging contaminants, and in designing and building water treatment plants that can deal with them. Schwab's own research concentrates on detecting and tracking pathogenic microorganisms in food, water and the environment. He is currently working on better detection methods for noroviruses, which are the leading cause of non-bacterial gastroenteritis worldwide.
In the developing world, he says, the challenge is to provide basic sanitation in a way that is acceptable to people and can be sustained.
Melissa Opryszko, a PhD student at the Center for Water and Health, is studying a water treatment system being used in Ghana for rural communities that don't have access to piped water. An Irvine, California, company called WaterHealth International markets stand-alone "kiosks" that treat water from nearby lakes or rivers. The technology was originally developed by researchers at the University of California, Berkeley. People pay the equivalent of about 3 cents per 20 liters of water.
Opryszko is investigating five villages in Ghana that are using the kiosks. So far she has found that the water being produced by the kiosks is, in fact, safe. Unfortunately, it is often contaminated after people take it home, by being mixed with untreated water, or exposed to contaminants from unwashed hands, animals, or other sources. Opryszko says that more education, or possibly the addition of chlorine, will probably be needed.
"It's one thing to produce high quality water. It's another to maintain it until it's consumed," Schwab says. "It has to be safe from source to sip."