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Bedding down your immune system -

An old or uncomfortable mattress can affect your health, and we're not just talking about sleepless nights. A poor mattress can throw your immune system off-kilter because without sufficient sleep the body makes fewer cytokines, the protein responsible for kicking in your immune response. Other consequences of a bad mattress range from allergies to chronic back pain.

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Your kitchen towels are dirtier than you think -

Your kitchen towel may harbor a number of different bacteria. Multi-use of kitchen towels can put households at risk of food poisoning, as they can spread germs through the cross-contamination of potential pathogens.

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House dust can induce asthma -

House dust is mostly made up of a cringe-worthy concoction of human hair and shed bits of skin, dead microscopic bugs, dirt, food debris, and organic fibers from clothes and bedding. Everything, in fact, a dust mite worships. And house dust mites are one of the most common causes of airborne allergens worldwide. That's bad news for anyone with asthma. Keep the dust to a minimum in your home by vacuuming and dusting every few days.

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Plaque attack! -

Toothbrushes become contaminated with pathogenic bacteria from dental plaque by the very fact they are used to clean a dirty mouth. Storing a toothbrush in a dirty environment only serves to promote the transmission of diseases. After use, keep it dry and covered.

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Soiled goods -

Houseplants lend room interiors a natural and organic look, and are generally known to enhance the air quality inside your home. But beware! Houseplants may also induce your allergy symptoms if over-watered. Damp soil can promote the growth of microorganisms, which can trigger allergic reactions.

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Hose pipe ban -

The water in a garden hose is not generally safe for drinking. Polyvinyl chloride (PVC) hoses contain dangerous contaminants, including lead, bromine, tin, and phthalates. Your body can be exposed to these contaminants if you drink or use water from PVC hoses. And it should be noted that lead is especially hazardous for young children.

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Smelling good can damage your health -

Perfumes and fragrances are actually highly toxic. The numerous chemicals used in their manufacture include acetone, benzyl alcohol, ethanol, and methylene chloride. Directly inhaled, fragrance chemicals can cause irritation to the mouth, throat, eyes, and skin, among other debilitating symptoms.

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Watch out for those volatile chemical compounds -

Oil, gas, and paint—chemicals used frequently around the house—are often stored in a garage or outhouse. And the chances are you've come away feeling dizzy or with a headache after using or storing them! That's because these household products contain a volatile organic compound (VOC). Anyone sensitive to VOCs often complains of nausea and experiences eye, nose, and throat irritation. In rare cases, you can suffer damage to the liver, kidney, and central nervous system.

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Full of gas -

Quite apart from the risk of an explosion, a malfunctioning gas appliance—stove, water heater, etc.—can make you feel sick. If it's not functioning properly, your home may be exposed to carbon monoxide, nitrogen, and sulfur dioxides. Warning symptoms include headaches, nausea, and fatigue.

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A cut below the rest -

Chopping boards and food poisoning can come hand in hand. A potential breeding ground for harmful bacteria like E.coli, a dirty chopping board can spread dangerous germs to food. Preventative measures include thoroughly washing cutting boards after use, and having several boards in the kitchen for different foods.

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Coffee can do more than keep you awake -

Mold and fungus thrive in moist and dark places—and that includes your coffee maker. Failure to clean the reservoir after use can promote the growth of many types of harmful bacteria, including yeast, staphylococcus, and coliform. if you have a weak immune system, mold sickness can be particularly virulent.

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Wash and brush up -

Frequently used makeup brushes act as breeding grounds for germs. Without being washed, they can end up being contaminated with bacteria and skin pathogens such as staphylococcus, streptococcus, and E.coli. In extreme cases, these contaminants can lead to infections in the body, including life-threatening conditions such as sepsis.

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Food storage issues -

Did you know that your refrigerator vegetable tray can contaminate your food? This is because the trays are very likely to harbor salmonella, listeria, yeast, and mold. Reduce the risk of cross-contamination by making sure your refrigerator temperature is under 5°C (41°F), and that you're keeping washed vegetables away from unwashed vegetables.

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Cancer warning -

The dangers of asbestos are well documented. But despite today's stringent safety measures regarding new build housing, older homes (typically built before 1980) may feature cancer-causing lead or asbestos building materials, products that often include insulation, floor tiles, ceiling tiles, siding, and roofing. Before purchasing an older home, learn how to spot, avoid, and safely deal with asbestos. And always call in an expert if you're unsure.

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Problems with plastic -

Plastic containers used for storing food appear innocuous enough. But some can contain bisphenol A (BPA), a hazardous chemical that can be filtered in food if stored in these type of boxes when still hot.

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Not such a warm welcome -

Have you any idea what you bring into your home on the bottoms of your shoes? Bacteria as well as fecal matter can be tracked by shoes over a long distance before ending up wiped on a doormat. But all that does is contaminate the very item designed to clean soles and heels. Purchase a doormat made from material that's easily cleaned, and wipe it down using an antibacterial cloth at least once a week.

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Stub it out! -

A no-brainer really: smoking in the house is not only bad for the smoker, it's bad for everyone. There is no risk-free level of exposure to secondhand smoke, and it's especially dangerous to children whose lungs are still developing. Best solution? Stub out the habit!

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Getting under the skin -

Shaving is often a daily necessity for men and women who use a razor to remove unwanted hair. The problem is staphylococcus aureu—a bacterium that can cause infections—often finds its way onto razors. After colonizing the skin, these bacteria induce frequent outbreaks of pustules and boils. Reduce the risk of colonization by leaving razors in an upright position and in a dry atmosphere after use.

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Age-proofing your home -

If you're elderly, it's a good idea to equip your home with stabilizing bars in areas where a fall is likely, typically the bathroom, a hall, or a stairwell. In other words: age-proof your house to avoid fall-related injuries.

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Don't slouch on the couch -

Attention all those who lead a sedentary lifestyle: maintaining an inactive way of life can promote a host of bad health problems, including the unholy trinity of obesity, heart disease, and diabetes.

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Sponge grunge -

The workhorse of culinary cleanups, the kitchen sponge can collect, incubate, and spread pathogenic bacteria, meaning they could cause infections like salmonella in humans, leading to symptoms such as diarrhea, chills, dehydration, fatigue, and fever.

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Look under the surface -

Swimming is one of the most rewarding forms of exercise, but lurking in the water of swimming pools is a cocktail of chemicals that include chlorine, bromide, and algaecides. These can lead to eye and skin irritations and, in some cases, respiratory illnesses. The double whammy is that if you don't disinfect your pool at all, dangerous bacteria can form.

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Feline woes -

Think carefully before deciding to keep a house cat. Indoor felines will quickly overrun your home with pet dander—microscopic flecks of skin shed by animals with feathers or fur. These bits of skin can cause reactions in people who are specifically allergic to these triggers, and may experience congestion, sneezing, watery eyes, and skin rashes, among other adverse effects.

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Open and shut case -

Contrary to conventional wisdom, a refrigerator doesn't keep bacteria at bay. Its chief duty is to slow the growth of bacteria such as salmonella, E.coli, and botulinum in food. But here's the kicker: the more times you open and close the door of your refrigerator, the more it's exposed to warm and humid air—an operation that makes mold and bacteria grow faster. To counter this, make sure you clean your fridge at least once a month, preferably using a vinegar solution to wipe down all surfaces, including the racks, shelves, and drawers.

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Can the bacteria -

It's one of the most useful kitchen implements of the modern age. But by reusing a can opener without washing it, you run the risk of spreading germs to your food. Over time, food particles can attach themselves to the implement, which in turn allows harmful bacteria to take hold.

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Pet problems -

Pet accessories—items like food bowls, treats, and toys—are magnets for microorganisms, which may contain particles of fecal matter that can spread infection and cause human illness: diseases like campylobacter or salmonella that affect the intestines. Remember to always wash your hands after handling your pet. And wash your pet's food and water bowls every day with soap.

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Stay in the mix -

Few people bother to check a blender gasket: the small rubber part that goes between the jar and cutter. This component is generally moist, so it tends to attract contaminants like salmonella and E.coli. The problem is the blender gasket comes in direct contact with the food you eat. Skip on cleaning it and you could ingest enough of these harmful bacteria to fall ill.

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Room for improvement -

Wood stoves and fireplaces enhance any interior. Besides warming up the room, they provide a comfortable and romantic aesthetic. But remember: when lit, these emit carbon monoxide, nitrogen, and sulfur dioxides, and greatly reduce the air quality in the room. This can cause negative short-term effects, including dizziness, headaches, and fatigue. The rule of thumb? Remember to keep rooms well-ventilated when using these kinds of fires.

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Change of habit -

Most of us watch television, which means we all tend to share the remote control. Unfortunately, this can unwittingly channel a high percentage of bacteria between hands and fingers. Get into the habit of using sanitizing tissues to wipe down remote units.

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In the bag -

Cleaning the house using a vacuum cleaner is a commonplace chore—and replacing a full vacuum cleaner bag a necessary evil. But while in operation, a vacuum bag can emit all sorts of bacteria, molds, endotoxins, and allergens, even though it's housed in a sealed casing. These particles become airborne and can trigger allergic reactions in some people. At its worst, these bacteria can induce a variety of ailments, including gastrointestinal infections.

See also: Unexpected things that are dirtier than your toilet.

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