Using Canines in Source Detection of Indoor Air Pollutants

Dogs have been used extensively in law enforcement and military applications to detect narcotics and explosives for over thirty years. Dogs are regularly used in arson investigations to detect accelerants since they are much more accurate at discriminating between accelerants and by-products of combustion than field VOC detectors. Controlled laboratory studies have documented accurate detection by dogs of specific compounds associated with explosives and narcotics at air concentrations below 1 ppb. Relatively few applications have taken advantage of this canine capability in the environmental arena.

Dogs could be used to rapidly screen houses for problems such as vapor intrusion of a variety of VOCs, identifying the presence of mildews and toxic molds, or rapidly identifying houses where illicit pesticide use has occurred.

Dogs can also serve as a rapid screen to indicate the presence of a substance in air in a house and are also capable of moving towards the source of volatile materials. Benzene, toluene, ethylene, and xylene (BTEX) are major constituents of gasoline and frequent culprits in vapor intrusion into buildings from contaminated groundwater. Since indoor air contamination can also occur from household sources responsibility is often contested. Canines have the potential to provide an effective approach to screening for the contaminant source location.

A dog and handler team could screen a room for chemical contamination in a matter of minutes and an entire residence in well under an hour. For vapor intrusion investigations, a dog could be used both to cost effectively identify the source location of the air contaminant and do follow up 'sampling' after remediation is implemented.

Dogs' noses are such sensitive chemical detectors they can detect a target compound in the presence of confounding odors at orders of magnitude higher concentration. They are even capable of discriminating between a target compound and closely related ones. They can be trained to detect multiple target compounds (>20) and to move up gradient to the area of highest concentration. The bottom of the purple bars show the equilibrium air concentration over a water sample containing benzene, toluene, ethylbenezene or xylenes (BTEX), all common groundwater pollutants at the allowed drinking water concentration. The top of the bars shows the OSHA eight hour permissible exposure concentrations in the workplace. The lined area in the fifth column is a range of canine detection levels from a laboratory study at Auburn's Canine Detection Research Institute.

Detection Program at ERD Athens, Georgia

The Ecosystems Research Division in Athens, Georgia, a research laboratory under the auspices of EPA's Office of Research and Development, National Exposure Research Laboratory, is focusing on demonstrating the utility of dogs for indoor air quality assessments and evaluating implementation issues including cost effectiveness, animal welfare and quality assurance associated with their use.

The project includes three research phases. In all phases careful planning and monitoring is included to assure the health and safety of the dogs and handlers. First is a series of canine detection limit studies for low concentration aqueous solutions of compounds including test compounds, the BTEX suite of compounds, common contaminants from underground storage tank leaks and other compounds commonly implicated in vapor intrusion problems. In an initial dilution series with one of our training compounds, isopropyl alcohol, Sammy, our first detection dog, detected vapor concentrations below 1 ppb. Testing is done blind, i.e., the handler does not know which are targets and which are blanks. Searches are also done with free hides of samples so we can understand limits likely encountered in the field demonstration phase.

Following laboratory studies, the program will move to a field test phase. Vapor intrusion project researchers are working with the Georgia Environmental Management Authority to identify petroleum sites where the effectiveness of the use of dogs can be evaluated. The final phase of the project will be the development of recommended training and testing protocols for the use of scent detection dogs. Development of 'standard methods' and specific quality assurance protocols are a key component to acceptability of the use of dogs in environmental applications.

Sammy's handler, Sandy, puts him on a down stay prior to starting the search. This lets him know he is about to start a search and gets him focused on Sandy. This starting position also gives the handler the opportunity to get in position since Sammy is much quicker than the humans he works with.

Sammy and Coco: EPA's Research and Development Detecting Dogs

Sammy

Sammy, a three-year old Swedish Vallhund, is the first canine participant in the EPA's pollution detection dog research program. He is friendly, personable and completely toy obsessed. The willingness to use his nose, a quality shared by most dogs, and a strong play drive are two characteristics that make Sammy a good detection dog. In addition, he is comfortable in almost any environment and is not easily distracted from his job.

Sammy's enthusiasm got him in trouble early in life. He was returned to his breeder by his first owners because he would race around the yard and nip at the heels of the family's children. The parents thought he was dangerous and unmanageable. He came to live with Sandy, the project Principal Investigator, when he was nearly a year old.

Sammy holds the AKC's Canine Good Citizen (CGC) certificate and competes in agility trials with a junior handler. The manners he learned preparing for the CGC test and the training to go over, under and through obstacles in agility provided him with an excellent background for his current career.

Sandy shows Sammy the areas to be searched and is responsible for making sure a comprehensive search is performed. He has learned to search on top, under and behind furniture, boxes and anything else in a room.

When Sammy detects a scent that he is trained to detect, he moves to the area of highest concentration and sits to signal a find.

When Sammy alerts on a target compound, he is rewarded with food, a game of tug or a ball to chase. Sometimes he gets to play after he does a good search even if nothing is found.

Coco

Coco is a 3-year old rescue from the Madison-Oglethorpe County, Georgia Animal Shelter and has recently started training to become EPA's Research and Development second canine detection dog.

Coco is learning the search technique.