One of the big ideas in healthcare today is preventative medicine. Treat the causes instead of the symptoms, proponents say, and you’ll keep people healthy and avoid expensive procedures down the road. I wholeheartedly agree with this approach. To me, continuously investing in newer, better treatment strategies should be accompanied by a parallel efforts in minimizing and eliminating the potential causative agents.

Take cancer, for example. While some scientists are developing better drug delivery strategies — an effort I would never underestimate — others are exploring the genetic predispositions that make some of us more susceptible and trying to find ways to intervene before the disease appears.

But taking that approach singles out the individual organism for study. What about devising a strategy that addresses the entire system?

The link between environmental exposure and public health has long been recognized, but are we doing enough?

April Gu, a Northeastern University associate professor of civil and environmental engineering, is working on improving the water supply by removing disease-causing contaminants such as pathogens and toxic contaminants that may have various health impacts such as cancer.

It is equally important to invest in the prevention of potential root causes of disease — such as improving water and air quality — as the symptoms they may induce.

Researchers in Gu’s Environmental Biotechnology Laboratory develop biological platforms for testing water quality. Here’s how one of the platforms work: The biosensors use a biological component, such as DNA or protein, to biochemically bind contaminants. Changes to the bio-component result in a fluorescence signal that can be read with a portable device developed in collaboration with Tsing Hua University in Beijing.

Gu’s biosensors can detect contaminants on the micro- and nanogram levels, a capability that should not be overlooked: Long-term exposure to even a very small amount of a given contaminant could be enough to cause damage.

An element of particular interest to Gu’s lab is phosphorous, one of the planet’s most ubiquitous elements, which we strip from rocks and use in fertilizers for food production

Phosphorous in waste-water effluent is required by the Environmental Protection Agency to be kept at very low levels because of its known connection to eutrophication and possible toxic algal blooms. But the standard procedure for removing phosphorous often involves dumping other chemicals into the water, none of which have been regulated. For her part, Gu has been working on developing and optimizing a more sustainable, chemical-free process that removes phosphorous in a biological system.

Gu’s recent research has also shown that low levels of nanomaterials can disrupt the elemental ratios of algae over the long-term. “This may not seem like much,” she says, “but a change at the bottom of the food chain like that may affect the entire ecosystem, which could have major impacts.”

At the current consumption rate, worldwide phosphorous reserves are expected to dry up in 50 to 100 years. But Gu has a plan to help reverse this trend, launching a project to recover the phosphorous obtained through bioremediation efforts, a process that will recover phosphorous from wastewater treatment and products.

The choice is this: We could either treat the symptoms of water contaminants’ impact on our water supply or try to stop it before it wreaks havoc. One of these ideas sounds more appealing and cost-effective to me.