Meet Louie, WSP’s newest pollution dog

As a member of our Environment team, this beautiful, six-year-old Labrador Retriever may look like your average dog, but this former explosive detection dog is now trained to find the sources of chlorinated solvents that are wasted or improperly disposed of in natural and built environments. 


Snout to the ground and unleashed, he calmly saunters across a field… on a mission. With every inch of bush and grass that crosses his path, he sniffs incessantly… stopping momentarily, looking around, and sniffing some more as he moves on. He suddenly comes to stop, indicating that the hunt may be indeed over. He digs a little, points his paw toward the hotspot, then sits like a well-behaved dog and looks up at his owner and dog handler, Mette Algreen Nielsen, PhD and Project Leader, Contaminated Soil and Groundwater at Orbicon|WSP, for positive reinforcement. His mission is accomplished.

Meet Louie, WSP’s newest four-legged collaborator and Denmark’s first pollution detection dog. As a member of our Environment team, this beautiful, six-year-old Labrador Retriever may look like your average dog, but after an intensive six-month training this former explosive detection dog is now trained with one specific task in mind: finding the sources of chlorinated solvents that are wasted or improperly disposed of in natural and built environments.

Louie and dog owner

Detection or sniffer dogs have long been used across various sectors, such as military and law enforcement, fire departments, search and rescue units, medical teams, hospitality industry, and more. They are trained to identify specific odours and detect anything from illicit drugs, contraband and explosives, to missing persons, sewer pipeline leaks and bed bug infestations, through to diseases like cancer, diabetes and malaria.

Today, it is not uncommon to find sniffer dogs working in environmental spheres, performing ecological monitoring work for the protection of endangered species or helping manage biological threats of invasive species or diseases. As for Louie, he might possibly be the first pollution detection dog in the world trained to detect chlorinated solvents—chemical compounds that are readily used for commercial and industrial purposes, including metal cleaners/degreasers, paint thinners, pesticides, glues, and dry cleaning applications. When handled, stored and disposed of improperly, these compounds and their waste can release vapours into the air, seep into soils and groundwater and even end up in homes or workplaces, potentially posing environmental or health risks.

“As chlorinated solvents are often invisible, they can be located using traditional methods such as photoionization (PID) detectors, a sensor tool that screens for the presence of gases, reads volatile organic compounds (VOCs) concentration levels, indicating too-high levels, but not necessarily by product type,” says Mette.

This is where Louie steps in with his acute sense of smell, working on all types of projects to find the sources of chlorinated solvents in surface water, groundwater, soil and air. His ability to smell and react on the smallest concentrations of chlorinated solvents is truly extraordinary, something that would be quite impossible to do using other tools.

Louie can find many kinds of pollution with his extremely sensitive measuring device, which makes tracking the sources of pollution very efficient. For example, instead of drilling in different spots to search for pollution, through his keen sense of smell he can determine the spot that will be most successful for drilling. Furthermore, Louie can even find the sources of polluted water or toxic gases within a building, if built on a polluted plot.

There is a myriad of other benefits. With the use of Louie’s nose, sources of pollution can cover more space, in less time and with more accuracy. Detection dogs hold big potential within the pollution field, as they save both time and costs.

The Prowess of the Nose

The effectiveness of this non-traditional, yet innovative method to protecting the environment and human health is truly remarkable. For skeptics out there, consider the following. Mette recounted a story about working on a project where the client’s house was contaminated. Before the house would be taken down, the client requested that photos be taken and suggested taking them from the garden. As the client, Mette and Louie walked through the garden, Louie went through his detection motions, making a mark on the grass. Though surprised, the client was adamant that his garden was not polluted. But Mette knew better. When the bulldozer arrived the following week, it never had a chance to reach the house. The ground gave way in the garden, swallowing the bulldozer and exposing a well that was contaminated with chlorinated solvents at the spot where Louie had pointed out.

“In other cases,” Mette adds “we’ve found exposure in parts of houses that weren’t flagged by traditional methods.” In all evidence, she says that “we actually get better site investigations when we add in this sniffer dog method. And, this is very important when we must do remediation, we have all possible sources for this indoor problem to consider.”

Louie has been an asset to the team and clients alike. So much so, that the team has hired a new dog who is currently in training. As Mette notes, “having two dogs provides a more effective method. For one, the dogs will motivate each other to search better. While one dog rests, the other can search, and lastly two dogs making the same marking allows for double indication.”

Pollution detective dogs and dog owner

Safety First

For those concerned with Louie’s welfare while on duty, Mette affirms that he is very much engaged in finding the pollution, enjoys every minute of it and has a great bill of health that is maintained through routine annual veterinary visits.

“A dog’s nasal cavity is much longer when compared to humans. And due to this, Louie will not take in chemicals into his system as would humans. In addition, exposure to these solvents is time restrained and minimal, and the concentrations are too low to cause him any harm. These solvents cause issues when exposed over long-term, like many years. A dog’s lifespan is very short in comparison… passing away due to natural causes. To date, no reports have yet to indicate a negative impact on dogs involved in this line of work,” says Mette.

Louie’s work has been turning heads in Danish media, making front-page news in national newspapers and TV appearances on national television, and regional media.