Canada·In Depth

Bacteria myths and misconceptions

We've all heard about the threat bacteria poses lurking in common areas, but that conventional wisdom can sometimes fall flat in the face of science.

A recent CBC investigation in the Vancouver area found an astonishing number of bacteria lurking on seemingly innocuous mall food court trays. Other studies in recent years have found similar microbes in many places we frequent on a regular basis. But what can we actually believe? Here's a look at some common beliefs, and why it turns out sometimes that they aren't true.

The public washroom

Myth: Conventional wisdom, and our mothers, would have us believe the public toilet seat is the dirtiest thing on the planet. To even touch it, let alone sit down, could put us at risk for a plethora of unpleasant diseases.


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Fact: In actuality, the toilet seat is probably the cleanest part of any washroom. A 2002 University of Arizona study showed a public toilet seat has an average of 49 bacteria per square inch, a comparatively low number. There ends up being more bacteria lurking on the flushing handle, the door latch or in the air once the toilet is flushed.

Experts agree it's best to leave the stall right after you flush because it's likely that fecal bacteria will be launched into the air. Oddly enough, sinks in public washrooms harbour the most bacteria because the collected water acts as an ideal breeding ground.

The office

Myth: Most of us spend so much time in the office we may treat it as a second home and assume it's just as clean. With an army of cleaners coming through each evening, what sort of harm could there be?

Fact: Unfortunately, we're living in a state of denial about office cleanliness. According to Discovery Health, most health inspectors will shut down a restaurant when a surface has more than 700 bacteria per square inch, but your telephone, for example, can have upwards of 25,000 bacteria per square inch.

The mouthpiece is the worst offender, with bacteria hiding from your saliva or that of a co-worker. The Arizona study showed a typical desk can be up to 100 times dirtier than a kitchen counter. It's recommended that desks be wiped down with water at the very least, especially if you plan on taking lunch there. 

The grocery store

Myth: The only real health risks at the grocery store, we assume, come from not noting expiry dates on meat and dairy products or from rotting produce. Shopping carts are also understood to be hotbeds for germs to lurk and breed.

Fact: The biggest health threat won't necessarily be so easy to see. The irrigation spigots used to spray down vegetables can be caked with dirt. The water may be recycled through the system, increasing the risk for bacteria. Also, be aware of stagnant water, such as is present to store asparagus, since bacteria can thrive there.

Those shopping carts do not pose as much risk as the conveyer belt at the checkout counter, an NBC Today Show study found in 2006. The belt is not usually cleaned regularly and comes in contact with a variety of items, such as raw meat. It's best to wash your hands once you leave the store and make sure you take proper precautions when preparing your food.

The airplane

Myth: The biggest myth regarding germs and air travel is that you can get sick just by breathing the air because it's constantly circulated through the plane.

Fact: In fact, most planes have meticulous filtration systems and as long as your seatmate isn't coughing profusely, you're not at high risk. Airborne germs don't travel well on planes. Rhinovirus, the bug responsible for the common cold, is transmitted through surface contact so the best bet for avoiding germs is to make sure you wash your hands frequently and avoid touching your nose or eyes.

The bank

Myth: Countless studies over the years have shown that nearly 100 per cent of paper money has a trace amount of cocaine on it. With those results, it's unimaginable what else might be found on our currency.

Fact: The possibility does exist for bacteria to be present on some cash. However, the likelihood for it to linger is low; money is usually quite dry and bacteria thrive in wet environs. ATMs, on the other hand, can pose a substantial risk, especially those with plastic buttons or touch screens since plastic can harbour bacteria better than metal because of its porous nature.

The gym

Myth: It's no secret the equipment at the gym is covered in unwanted bacteria. But as long as you wipe the machine down before you begin your set, everything will be fine.

Fact: It's actually the bacterial variety that is most astounding. Scientists have found staph, E. coli, enterobacter and even bacillus, which is present in soil and probably gets tracked in on a running shoe. Bacteria thrive in a gym setting because most of the equipment is sweaty and the moisture acts as an ideal breeding ground.

While it is important to wipe down equipment, it is also important to properly maintain your gym attire. Polyester, the fabric most commonly found in activewear, can allow bacteria to flourish. Make sure you wash your gear after each workout and try to avoid polyester.

The laundromat

Myth: With everyone's clothes running through the washing machines on a daily basis, it's impossible to ensure your laundry is truly coming clean. If possible, laundry done in your own home will have fewer bacteria.

Fact: The machines in the local laundromat are likely cleaner than your machines at home. Studies show up to 0.1 grams of fecal matter could be lurking in your underwear. Most home washing machines can't get the water hot enough to kill the bacteria. The industrial-strength machines at the coin laundry, however, have higher settings and can get the water much hotter.

Also, these machines are usually cleaned regularly, as are the folding tables and other facilities. If you're set on washing at home, it's best to wash undergarments separately from other clothes. You can also easily clean your machine every two to three loads by running an empty cycle with added bleach to kill lingering bacteria.

The hotel room

Myth: A common concern for hotel guests is the state of the linens on the bed. After all, it's impossible to truly tell when they have been changed and germs could always be lurking.

Fact: Most hotels change their sheets for each new guest. But even if they don't, cloth tends to dry out bacteria so they can't live on sheets or duvets for very long. The biggest risk is posed with items that don't get a regular cleaning such as a TV remote, the thermostat or even the Bible, a 2006 study from the University of Virginia found.

Bacteria can live for upwards of four days on these surfaces, so even the traces of sickness from an ill guest a few days before can stay in the room. It's best to wipe down as many surfaces as you can, no matter how odd it may seem.

Another tip is to avoid frequenting the cheapest hotel you can find since it may be cutting from its cleaning budget in order to save guests a few dollars on the room rate.