What Is Secondhand Smoke?


Secondhand smoke comes from both the smoke that smokers exhale (called mainstream smoke) and the smoke floating from the end of the cigarette, cigar, or pipe (called sidestream smoke).
It may seem pretty harmless, but secondhand smoke actually contains thousands of chemicals — from arsenic and ammonia to hydrogen cyanide — many of which have been proven to be toxic or to cause cancer (called carcinogens). High concentrations of many of these chemicals are found in secondhand smoke. In fact, secondhand smoke significantly increases a person's risk for:
  • respiratory infections (like bronchitis and pneumonia)
  • asthma (secondhand smoke is a risk factor for the development of asthma and can trigger attacks in those who already have it)
  • coughing, sore throats, sniffling, and sneezing
  • cancer
  • heart disease
So secondhand smoke doesn't just impact a person in the future. It can cause problems right now, like affecting someone's sports performance or ability to be physically active.

What Can You Do?

Chances are, you know someone who smokes. Maybe it's your Grandma or the guy you hang out with at your job at the mall. Whether you smoke or you're regularly around someone who does, it's never healthy to breathe in tobacco smoke. Even occasional or short-term exposure can take a toll on the body.
If you smoke, try to quit. Quitting isn't easy because smoking is highly addictive. But plenty of programs and people can help you make the brave effort to becoming smoke free. And just consider the benefits: You'll look, feel, and smell better, not to mention you'll have more money saved to go out and show off the newer, healthier you! Who knows — maybe knowing that you're protecting the people you love by quitting will help give you even more willpower to kick the habit.
If you don't smoke, ask the smokers you know to observe these two practical habits:
  1. Take all their smoke breaks outside — away from other people, especially kids and anyone who's pregnant. Smoke lingers in the air hours after cigarettes are put out. That means if a smoker is puffing away anywhere inside, other people are inhaling that smoke, too. Because smoke sticks to people and their clothing, when smokers come back inside, they should wash their hands and change their clothing, especially before holding or hugging children.
  2. Never smoke in a car with other people. Even exhaling out the window does little, if anything, to reduce smoke exposure.
It's been scientifically proven that secondhand smoke is dangerous. So, hopefully the smokers in your life will be willing to take these simple steps.
Just as a person who smokes chooses to light up, nonsmokers have a choice, too — to walk away from other people's smoke at home, school, work, restaurants, even friends' and family members' houses. New laws are making it easier all the time for nonsmokers to lead smoke-free lives.
Taking a stand on secondhand smoke will keep you much healthier and possibly even help someone you love think twice about their own unhealthy habit, too.

 Dust Mite Allergy

 Definition

Dust mite allergy is an immune system reaction to a certain dust mite protein. This reaction triggers inflammation in the lining of the nasal passages (allergic rhinitis), causing sneezing, runny nose and other signs and symptoms associated with hay fever. 

For some people, dust mite allergy may be the primary cause of inflammation and contraction of airways of the lungs (asthma), resulting in wheezing, shortness of breath and other breathing difficulties. 

Dust mites, relatives of the spider, are too small to see without a microscope. Dust mites eat skin cells shed by people, and they thrive in warm, humid environments. In most homes, bedding, upholstered furniture and carpeting provide an ideal environment for dust mites. 

Steps to reduce the number of dust mites in your home can often control dust mite allergy. Medications or other treatments may be necessary to relieve symptoms and manage asthma. 

Symptoms

Dust mite allergy symptoms caused by inflammation of nasal passages include:
  • Sneezing
  • Runny nose
  • Itchy, red or watery eyes
  • Nasal congestion
  • Itchy nose, roof of mouth or throat
  • Postnasal drip
  • Cough
  • Facial pressure and pain
  • Frequent awakening
  • Swollen, blue-colored skin under your eyes
  • In a child, frequent upward rubbing of the nose
If your dust mite allergy contributes to asthma, you may also experience:
  • Difficulty breathing
  • Chest tightness or pain
  • An audible whistling or wheezing sound when exhaling
  • Trouble sleeping caused by shortness of breath, coughing or wheezing
  • Bouts of coughing or wheezing that are worsened by a respiratory virus such as a cold or the flu
A dust mite allergy can range from mild to severe. A mild case of dust mite allergy may cause an occasional runny nose, watery eyes and sneezing. In severe cases, the condition is ongoing, or chronic, resulting in persistent sneezing, cough, congestion, facial pressure or severe asthma attack. 

When to see a doctor
Some signs and symptoms of dust mite allergy, such as a runny nose or sneezing, are similar to those of the common cold. Sometimes it's difficult to know whether you have a cold or an allergy. If symptoms persist for more than one week, call your doctor.

If your signs and symptoms are severe — such as severe pain, difficulty sleeping or wheezing — call your doctor. Seek emergency care if wheezing or shortness of breath rapidly worsens or if you are short of breath with minimal activity.

Causes

Image showing dust mite    Dust mite

Dust mites eat skin cells people shed, and rather than drinking water, they absorb water from humidity in the atmosphere. They thrive in temperatures around 70 F (21 C) and a relative humidity around 70 percent. 

Household dust contains all kinds of tiny particles, but a large portion of it is made up of human skin cells. This dust is easily trapped in the fibers of bed linens, furniture cushions and carpeting. These materials also hold moisture well. Consequently, bedrooms are ideal habitats for dust mites.
Dust also contains the feces and decaying bodies of dust mites, and it's a protein present in this dust mite "debris" that's the culprit in dust mite allergy. 

What causes the allergic reaction
An allergic reaction is somewhat like a case of mistaken identity within your body's immune system. Normally, your immune system generates antibodies to protect your body against bacteria, viruses or toxic substances. 


If you have dust mite allergy, your body generates an allergy-causing antibody to a protein found in the dust mite debris. In other words, it's mistakenly identified this protein as something that could harm you. Once your body has developed an allergy-causing antibody to a particular agent (allergen) — in this case, the dust mite protein — your immune system will be sensitive to it. When you inhale dust mite debris, your immune system responds and produces an inflammatory response in your nasal passages or lungs. 

The dust mite allergen can cause two kinds of immune system responses in the airways of your lungs. An allergen can prompt inflammation in air passages. Therefore, prolonged or regular exposure to the allergen can cause the ongoing (chronic) inflammation associated with asthma. Exposure to an allergen also may cause sudden, severe constriction of air passages (bronchospasms). 

Risk factors

The following factors increase your risk of developing a dust mite allergy:
  • Family history. You're more likely to develop a sensitivity to dust mites if allergies run in your  family.
  • Exposure. Being exposed to high levels of dust mites, especially early in life, increases your risk.
  • Age. You're more likely to develop dust mite allergy during childhood or early adulthood.

Complications

Ongoing (chronic) inflammation of tissues in the nasal passages caused by dust mite allergy can obstruct your sinuses, the hollow cavities connected to your nasal passages. These obstructions may make you more likely to develop infections of the sinuses (sinusitis).
People with asthma and dust mite allergy often have difficulty managing asthma symptoms. They may be at risk of asthma attacks that require immediate medical treatment or emergency care.

Preparing for your appointment

If you're experiencing runny nose, sneezing, wheezing, shortness of breath or other symptoms that may be related to an allergy, you'll probably start by seeing your family doctor or general practitioner. Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to prepare for your appointment. 

What you can do
  • Write down any symptoms you're experiencing, including any that may seem unrelated to allergy-like symptoms.
  • Write down your family's history of allergy and asthma, including specific types of allergies if you know them.
  • Make a list of all medications, as well as any vitamins or supplements that you're taking.
  • Ask if you should stop any medications, for example, antihistamines that would affect the results of an allergy skin test.
Preparing a list of questions will help you make the most of your time together. For symptoms that may be related to dust mite allergy, some basic questions to ask your doctor include:
  • Are my symptoms most likely an allergic reaction, or are they the result of a cold?
  • Will I need any allergy tests?
  • Should I see an allergy specialist?
  • What is the best treatment?
  • Is there a generic alternative to the medicine you're prescribing me?
  • Are there any brochures or other printed material that I can take home with me? What Web sites do you recommend visiting?
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something. 

What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:

  • When did you first begin experiencing symptoms?
  • Are symptoms worse at certain times of day?
  • Are the symptoms worse in the bedroom or other rooms of the house?
  • Do you have pets, and do they go in the bedrooms?
  • What kind of self-care techniques have you used, and have they helped?
  • What, if anything, appears to worsen your symptoms?
  • Is there dampness or water damage in the home or workplace?
  • Do you have an air conditioner in the home?
Issues for people with asthma
If you already have been diagnosed with asthma and are having difficulty managing the disease, your doctor may talk to you about the possibility of allergies. Although allergies are a major contributing factor to asthma, the influence of allergy on asthma severity isn't always obvious.
The impact of a pollen allergy may be noticeable because the allergy is seasonal. For example, you may have more difficulty managing your asthma for a short time during the summer. Dust mite allergy, on the other hand, is due to something to which you're constantly exposed to some degree. Therefore, you may not recognize it as a factor complicating your asthma when, in fact, it may be a primary cause. 

What you can do in the meantime
If you suspect that you may have a dust mite allergy, take steps to reduce house dust, particularly in your bedroom. Keep your bedroom clean, remove dust-collecting clutter and wash bedding in hot water that is at least 130 F (54.4 C). 


Tests and diagnosis

Your doctor may suspect dust mite allergy based on symptoms, an examination of your nose and your answers to his or her questions. He or she may use a lighted, instrument to look at the condition of the lining of your nose. If you have an allergy to something airborne, the lining of the nasal passage will be swollen and may appear pale or bluish. 

Your doctor may suspect a dust mite allergy, based on your comments. For example, if your symptoms are worse when you go to bed or while cleaning — when dust mite allergens would be temporarily airborne — you may have dust mite allergy. If you have a pet — another common source of allergies — it may be more difficult to determine the cause of the allergy, particularly if your pet sleeps in your bedroom. The source of your allergy may be clearer after you take steps to reduce levels of the possible allergens from your home. 

Allergy skin test
Your doctor may suggest an allergy skin test to determine exactly what you're allergic to. You may be referred to an allergy specialist (allergist) for this test.
In this test, tiny drops of purified allergen extracts — including an extract for dust mites — are pricked onto your skin's surface. This is usually carried out on the forearm, but it may be done on the upper back.
The drops are left on your skin for 15 minutes before your doctor or nurse observes your skin for signs of allergic reactions. If you're allergic to dust mites, you'll develop a red, itchy bump where the dust mite extract was pricked onto your skin. The most common side effect of these skin tests is itching and redness. This usually goes away within 30 minutes. 

Blood test
In some cases a skin test can't be performed because of the presence of a skin condition or because of interactions with certain medications. As an alternative, your doctor may order a blood test that screens for specific allergy-causing antibodies to various common allergens, including dust mites. This test may also indicate how sensitive you are to an allergen. 

Treatments and drugs

The first treatment for controlling dust mite allergy is avoiding dust mites as much as possible. When you minimize your exposure to dust mites, you will have allergic reactions that are less often or less severe. However, it's impossible to completely eliminate dust mites from your environment. You may also need medications to control symptoms. 

Allergy medications
Your doctor may tell you to take one of the following medications to improve nasal allergy symptoms:

  • Antihistamines reduce your body's production of a chemical that is active in an allergic reaction. These drugs relieve itching, sneezing and runny nose. Prescription antihistamine tablets include desloratadine (Clarinex) and fexofenadine (Allegra). Azelastine (Astelin) is a prescription antihistamine taken as a nasal spray. Over-the-counter antihistamine tablets (Claritin, Zyrtec), as well as antihistamine syrups for children, also are available.
  • Corticosteroids delivered as a nasal spray can reduce inflammation and control symptoms of allergic rhinitis. These drugs include fluticasone (Flonase) and mometasone furoate (Nasonex). Nasal corticosteroids provide a low dose of the drug and are not associated with the long-term risk of oral corticosteroids.
  • Decongestants can help shrink swollen tissues in your nasal passages and make it easier to breathe through your nose. Some over-the-counter allergy tablets combine an antihistamine with a decongestant. Oral decongestants can increase blood pressure and shouldn't be taken if you have high blood pressure or cardiovascular disease. In men with an enlarged prostate, the drug can worsen the condition. Talk to your doctor about whether you can safely take a decongestant.
    Over-the-counter decongestants taken as a nasal spray may briefly lessen allergy symptoms. If you use a decongestant spray for more than three days in a row, it can contribute to congestion.
  • Cromolyn sodium prevents the release of an immune system chemical and may reduce symptoms. You need to use this over-the-counter nasal spray several times a day, and it's most effective when used before signs and symptoms develop. Cromolyn sodium doesn't have serious side effects.
  • Leukotriene modifiers block the action of certain immune system chemicals. Your doctor may prescribe this prescription tablet, montelukast (Singulair), if you can't tolerate corticosteroid nasal sprays or an antihistamine nasal spray. Possible side effects include headache. Less common side effects include abdominal pain, cough, dental pain and dizziness.
Other therapies
  • Immunotherapy, a series of allergy shots, can "train" your immune system not to be sensitive to an allergen. One to two weekly shots expose you to very small doses of the allergen, in this case, the dust mite protein that causes an allergic reaction. The dose is gradually increased, usually during a three- to six-month period. Maintenance shots are needed every four weeks for three to five years. Immunotherapy is usually used when other simple treatments are not satisfactory.
  • Nasal lavage is the use of a saltwater (saline) rinse for your nasal passages. Your doctor may suggest a saline rinse to help lessen congestion, sneezing and postnasal drip. You can purchase over-the-counter saline sprays or nasal lavage kits with devices, such as bulb syringes, to administer a rinse. You can make your own solution by mixing 1/4 teaspoon (1.2 milliliters) of salt with 2 cups (0.5 liter) of warm water. 

Lifestyle and home remedies

Avoiding exposure to dust mites is the best strategy for controlling dust mite allergy. While you can't completely eliminate dust mites from your home, you can significantly reduce their number. Use these suggestions:
  • Use allergen-proof bed covers. Cover your mattress and pillows in dust-proof or allergen-blocking covers. These covers, made of either vinyl or tightly woven fabric, prevent dust mites from colonizing the mattress or pillows. Encase box springs in vinyl or plastic covers.
  • Wash bedding weekly. Wash all sheets, blankets, pillowcases and bedcovers in hot water that is at least 130 F (54.4 C) to kill dust mites and remove allergens. If bedding can't be washed hot, put the items in the drier for at least 20 minutes at a temperature above 130 F (54.4 C) to kill the mites. Then wash and dry the bedding to remove allergens. Freezing nonwashable items for 24 hours also can kill dust mites, but this won't remove the allergens.
  • Keep humidity low. Maintain a relative humidity between 30 and 50 percent in your home. A dehumidifier or air conditioner can help keep humidity low, and a hygrometer (available at hardware stores) can measure humidity levels.
  • Choose bedding wisely. Avoid wool or down bedcovers that trap dust easily and are difficult to clean frequently.
  • Buy washable stuffed toys. Wash them often in hot water and dry thoroughly. Also, keep stuffed toys off beds.
  • Remove dust. Use a damp or oiled mop or rag rather than dry materials to clean up dust. This prevents dust from becoming airborne and resettling.
  • Vacuum regularly. Vacuuming carpeting and upholstered furniture removes surface dust — essentially the dust mites' food supply — but vacuuming isn't effective at removing most dust mites and dust mite allergens. Use a vacuum cleaner with a double-layered microfilter bag or a high-efficiency particulate air (HEPA) filter to help decrease house-dust emissions from the cleaner. If your allergies are severe, leave the area being vacuumed while someone else does the dirty work. Stay out of the vacuumed room for 20 minutes after vacuuming.
  • Cut clutter. If it collects dust, it also collects dust mites. Remove knickknacks, tabletop ornaments, books, magazines and newspapers from your bedroom.
  • Remove carpeting and other dust mite habitats. Carpeting provides a comfortable habitat for dust mites. This is especially true if carpeting is over concrete, which holds moisture easily and provides a humid environment for mites. If possible, replace wall-to-wall bedroom carpeting with tile, wood, linoleum or vinyl flooring. Consider replacing other dust-collecting furnishings in bedrooms, such upholstered furniture, nonwashable curtains and horizontal blinds.
Air purifiers
Air purifiers collect airborne dust in your home and can help with controlling dust if you also maintain vigorous cleaning practices. But purifiers won't remove dust mites because the mites are too heavy to remain airborne long enough to be filtered through an air purifier. Some dust mites may be airborne right after cleaning, but they quickly settle again onto surfaces.


Reference :   Mayo Clinic



Question No 1

Will an air purifier remove cigarette smoke?

I'm thinking about buying an air purifier. Do any of them work on cigarette smoke?

 

Answer

from Richard D. Hurt, M.D. ( Mayo Clinic )
If you're considering buying an air purifier, you have a multitude of choices. But if you want an air purifier that will eliminate cigarette smoke, you're out of luck. Tobacco smoke particles are so energized that even the most efficient ventilation systems will not reduce the exposure. Further, most air purifiers, also called air cleaners, are not designed to remove gaseous pollutants, which are a major component of cigarette smoke. 

Mechanical air filters, such as HEPA filters, and electronic air cleaners, such as ionizers, target particles, but tobacco smoke particles are designed to be small enough to be inhaled into the outer reaches of the lungs and, thus, are not trapped by such devices. Other air cleaners generate ozone, which is actually a lung irritant. At levels that don't exceed public health standards, ozone has little ability to remove air contaminants such as cigarette smoke.
The best way to protect nonsmokers from secondhand smoke is to not allow smoking in your home. If you smoke, this is another good reason to stop.