Dogs vs. Machine for Detecting Explosives

Terminal One at Pearson International Airport is an assemblage of straight lines, shallow curves and smooth surfaces. It looks like the home of technology, a place where things could run smoothly in the complete absence of life.

Inside, an electronic arsenal keeps at bay terrorists, firearms, bombs, narcotics and farm pests. The arsenal includes hi-tech gadgets that detect explosives and drugs, X-ray machines, and biometric iris scanners that identify travellers based on the patterns in their eyes.

It also includes one "no-tech gadget" the domestic dog.

Dogs have been humankind's detection and tracking device of choice for hundreds, if not thousands, of years.

In the past 50 years, police, the military, airports, security and others have used canines to sniff out drugs, bombs, gunpowder, currency, landmines, gas leaks, food and human bodies.

In London, after two rounds of terrorist bombings, the police are using dogs to check backpacks in the London Underground and at train stations.

But in an age when new techno gadgets come online everyday, rendering yesterday's model obsolete faster than you can point and click, how long will it be before technology replaces man's best friend?

"It will happen, and it has to happen because we're living in a very high-tech society right now," says Ron Mistafa, whose Alberta company, Detector Dog Services International, trains and sells German shepherds, giant schnauzers, Labrador retrievers and Belgian Malinois.

Mistafa reckons he has no more than 15 years before his dogs have been replaced once and for all by machines.

In many respects, it has already happened at Pearson.

"We don't use dogs," says Kevin McGarr, vice-president of strategy for Canadian Air Transport Security Authority (CATSA), the Crown corporation that inspects passengers and their baggage before they board (the federal Canadian Border Services Agency handles arrivals).

"We use machines and screening officers... I'm not sure why other agencies would use dogs."

Thirty years ago, airports didn't use anything, says Mark Elliott, director of product management for Smiths Detection (Toronto Ltd.), which makes many of the airport inspection machines. "Then they put in metal detectors because the threat was guns and knives."

Next came X-ray machines, then explosives detectors. "In many cases, it's a matter of a new threat, plus the capability being developed to detect it," Elliott says.

So now airports are full of machines."Every airport in Canada, no matter how big or how small, has one of our Ionscan explosives detectors," Elliott boasts.

With an Ionscan, a security or Customs officer wipes a passenger's baggage, transferring solid particles to a swab that is put into the machine. The device breaks down the molecules into smaller particles, creating a fingerprint that is processed by a computer. The software contains a database of fingerprints for substances such as drugs and explosives.

"The biggest improvement in the last 10 to 15 years was going to trace technology from vapour technology," Elliott explains. This has made it possible to detect vapourless explosives such as C4 and makes it simple to upgrade the Ionscans to detect substances newly recognized as threats, he says.

In recent years, the Ionscan has been reconfigured to detect ecstasy and date rape drugs such as Rohypnol.

Besides arriving passengers, the Canadian Border Services Agency (CBSA) checks cargo and mail arriving by air, rail, sea and sometimes truck. For doing checks in remote places, it has mobile stations.

Ian Falzon, acting superintendent of CBSA's commercial operations at the airport, shows off the prototype "Comet" truck. It's a Swiss Army truck of sorts, with sliding panels, pull-out shelves, extendable ladders, a generator and gadgets including an Ionscan, DVD players and a snake-eye scope for peering inside packed crates and boxes. There's also a machine called a Sabre, resembling a hand-held vacuum cleaner. It can detect powders but also has a sniffer mode for detecting gases.

"If the dog is not here," says Falzon, "this is an excellent replacement."

His comment is telling.

Even at Toronto's state-of-the-art airport, machines haven't completely replaced dogs.

Checking for illegal foods that might carry foot-and-mouth disease, avian flu, mad-cow or any number of insect or microbiological pests falls squarely on the tiny shoulders of the CBSA's corps of beagles.

Drug, firearm and currency dogs patrol the agency's warehouses, the international postal facility and the airport. It's all part of a long tradition.

"Dogs have been used for hundreds, possibly thousands, of years to track animals and track men. It's a very short way to go to check for specific substances," says Stanley Coren, a professor of psychology at the University of British Columbia who has written a bestselling series of books on dogs, most recently How Dogs Think What the World Looks Like to Them and Why They Act the Way They Do.

"For dogs, the sense of smell is really what the sense of vision is for human beings. It's their most important single sense," Coren says.

Dogs have 300 million olfactory cells in their noses, while humans have 5 million, Coren explains. And the part of the brain processing smell is 40 times larger in dogs than in people.

Detector dogs have shut out machines for a lot of police work.

On "common detector dog day" at the Air Canada Centre, canine teams from Toronto's police dog services are taking turns practising their skills. The dogs specialize in drugs, firearms, explosives or cadavers.

Their officers work different shifts, but once every three months Sgt. Paul Caissie gathers them to train together. Caissie's own floppy-eared sidekick, Bandit, is a drug dog. "Most people look at my little springer spaniel and say, 'That's a police dog?' "

But the choice wasn't random. Bandit is compact and able to search small spaces. His cuteness helps, too. Offenders searched by Bandit have a hard time convincing the court that excessive force was used.

Const. John Gerrits strides down the fifth-floor hallway of the ACC. Alongside him is Buster, a yellow Labrador retriever trained to detect gunpowder and drugs such as heroin, hash and ecstasy.

Gerrits dons a pair of leather gloves as Buster looks on expectantly, his tail wagging in anticipation. Gerrits leads him by a leash onto a series of balconies overlooking the stadium floor.

"Come, come, come," the strapping officer urges in the high, lilting voice that people use with babies. Buster's nose sweeps to and fro and so does his tail, only faster. Gerrits directs him, moving chairs out of the way, until Buster pauses at a damaged part of the wall, sniffing intently. He sits down and scratches at it. That's where a bag of white powder has been concealed.

Caissie tosses Buster a small knot of towel, his favourite toy. The dog leaps and rolls, pawing and gnawing at the toy, his wagging tail a blur.

"A machine could not do what we (police dog services) do now," Caissie says firmly.

A machine can't subdue a suspect, for instance.

"When you find him, then what?" Caissie asks.

Though the police use dogs to hunt for bullet casings, forensics specialists use metal detectors. Those turn up various metal objects, Caissie says, "but I've never seen them find what they're looking for."

There are things dogs can't do. For instance, the Ionscan identifies substances while most detector dogs respond the same way to gunpowder and crack cocaine.

And dogs can only detect substances that release a vapour, says Ulli Krull, a professor of chemistry at the University of Toronto in Mississauga who does research and teaches on biosensors.

Machines, he says, can detect compounds that don't "smell."

"A dog has to go to the bathroom. A dog is distracted. A dog can only work for an hour or two before it needs a rest," Krull adds. "I've never seen one of these instruments sit down and say, 'Aw, give me a coffee break.'"

But Coren says dogs trump technology in significant ways. First, they do what's called gradient detection - they can lead you to the source of a scent.

"Dogs do that automatically. Human beings (with machines) have to cast around. It's slow. You might catch it, you might not catch it."

Secondly, relative to their level of sensitivity, dogs are very portable. "If you give me a room-sized station, I can probably develop something that can sniff as well as a dog," Coren says. "But portable? Um, no, I don't think so."

That's what makes dogs indispensable for police searches. Caissie estimates one dog searches more effectively than 10 officers.

"We can cover more area in less time," agrees Marty, one of CBSA's dog masters at the airport. He and Ozzie, a border collie cross, have made so many drug seizures that he doesn't want his last name used, lest those he has caught come looking for him.

Last year at Pearson, the CBSA made more than 760 drug seizures worth $140 million.

Still, the police and CBSA agree that machines and dogs both have their place in detection work.

"One can't replace the other. They're both very valuable tools," says Caissie.

The Toronto police also use devices such as portable X-ray machines for bomb detection.

Officers at CBSA say they use dogs and machines as independent tools that complement one another. And they're quick to point out that neither dog nor machine is much use on their own. It takes intelligent, well-trained humans to produce meaningful results.

Says CBSA superintendent Falzon, "The tools are only as good as the officer operating them."

For now, that's true, but the next step for machines is to make operators obsolete. Automation cuts out the expense of the operator and removes human error, says Elliott of Smiths Detection.

But, he adds, "I still to a certain extent think that machines will never replace everything, and I just have a sense that dogs may be one of those things."

Elliott recalls hearing recently about dogs sniffing out cancerous moles on human skin.

"Now how does that work?" he asks in a tone of awe.

"It may be one of those things that we always have trouble explaining and we can never copy."

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