Environmental control of allergens

What is environmental control of allergens?

  • A system of preventative measures to reduce allergic symptoms by limiting exposure to the allergens that cause your immune system to overreact and treat them like they’re dangerous to your health
  • Whether allergic symptoms are mild, seasonal, frequent or debilitating, controlling your environment is critical by following these steps to limit exposure to common allergens such as:
    • Pollen from grass, trees and weeds
    • Animal dander (skin flakes)
    • Dust mites (tiny organisms)
    • Cockroaches
    • Mold

Allergen-specific measures

Dust mites
These microscopic eight-legged creatures live mostly on shed human skin flakes. Because they grow best in warm, humid areas, their levels have increased in energy-efficient homes with limited ventilation, higher indoor temperatures and high humidity. They thrive in mattresses, pillows, bedding, carpet, upholstered furniture and stuffed animals.

  • Bed – Encase mattress, box spring and pillows with allergy-proof covers. Airtight cloth covers are more durable and comfortable than vinyl or plastic but all are sufficient.
  • Bedding – Wash bedding in hot water (130 degrees) at least once every two weeks.
  • Dust collectors – Remove stuffed furniture, wall pennants, cloth hangings, extra pillows, canopies, comforters with down or feathers and heavy drapes. Place stuffed animals in freezer for 12 hours every 10-14 days to kill dust mites.
  • Dust – Damp-dust once or twice a week.
  • Humidity – Avoid using humidifiers or vaporizers in bedrooms. Use dehumidifiers in basement year-round and in rest of house during summer months.
  • Floors – Damp-dust bare floors.
  • Carpeting – Consider replacing carpets with bare flooring since carpets harbor up to 100 times more allergens. Vacuum wall-to-wall carpets using a HEPA or electrostatic filter and tannic acid spray twice a week. Wash throw rugs in Borax.
  • Closets – Limit for clothing use only and not storage of dust collectors.
  • Air cleaners – These offer limited benefit since dust mite allergens are carried on large particles that quickly settle onto surfaces.

Indoor mold
Mold thrives in moist, damp places, often on basement walls and floors, window moldings, shower curtains, bathroom walls, ceilings and fixtures.

  • Humidity – Use dehumidifiers that drain continuously into pipes or sinks instead of needing to be emptied. Paint brick or cinder block basement walls with mold inhibitor.
  • Bathrooms – Wash bathroom tiles and grout frequently. If mildew is present, clean with a mold-specific disinfectant (Pine-Sol, Lysol, Tilex, Clorox, X-14). That pink line along the edge of your shower or tub is mold. Remove excess shower humidity with exhaust fans or open windows.
  • Bedrooms – Encase mattresses and pillows in air-tight covers to reduce dampness.
  • Carpets – Remove basement carpets that have gotten repeatedly wet. Remove carpets from bathrooms.
  • Air conditioners/whole house humidifiers – Examine both for mold and clean filters frequently.
  • House plants – Keep plants clean, minimal and out of bedrooms. Don’t stir up soil.
  • Closets – Dry clothes and shoes before storing in dry, well-lit closets.
  • Kitchen – Check food for mold growth. Use exhaust fan to remove excess humidity when cooking. Clean garbage containers frequently.
  • Firewood – Store outside since mold can be present on wood bark.
  • Windows – Seal tightly and wipe condensation daily.
  • Utility room – Vent clothes dryer to the outside.

Outdoor mold
Mold grows in fallen leaves, soil, moist debris, mulch, wooded areas and barns and thrives year-round in tropical climates. It can be carried by air or activity, peaks in summer/fall and tapers off after first frost.

  • Install proper drainage around home to avoid excess mold growth. Direct down spouts away from home.
  • Remove leaves and debris. Keep compost away from house.
  • Avoid heavily shaded lawn and home if possible.
  • Use high-quality ground cloth and preventive allergy medications when hiking and camping in woods.
  • Avoid raking and playing in leaves.
  • Avoid mowing grass or being around freshly cut grass, which kicks up mold.

Grass and tree pollen allergies are most common in spring, while ragweed pollen allergy symptoms typically occur in late summer to early fall. Since pollens can travel great distances and removing the source is impossible, focus on avoiding pollens at their height and keeping them out of your home.

  • Keep home and car windows closed and use air conditioning if needed to clean, cool and dry air. Avoid fans in open windows.
  • Stay indoors on dry, windy days when pollen counts are highest.
  • Avoid outdoor activities during pollen peak times. Tree pollen counts peak in early morning; ragweed in late morning; and grass pollen in early to mid-afternoon.
  • Shower and wash hair each night before bed to remove pollen.
  • Avoid mowing lawns, which stirs up pollens, and being around freshly cut grass. If you must mow, wear eye goggles.
  • Don’t hang sheets or clothing to dry outside because pollens can collect in them.
  • Wash hands often and avoid rubbing eyes after being outside.
  • Change air filters in HVAC units monthly.
  • Clean pets’ paws and fur when they come indoors to reduce bringing in allergens.

Pet dander
Pet dander, hair and saliva are the most significant sources of pet allergens. Pet dander strongly affects development and severity of asthma and allergies. Children with strong family allergy history are more likely to develop asthma/allergies, even with low levels of allergen exposure. “Allergen-free” or “hypo-allergenic” breeds of cats, dogs, ferrets, birds, rabbits, hamsters, gerbils, guinea pigs or other animals with hair or fur don’t exist; some dander is simply more tolerated than others.

Not having pets in the home (or removing them when allergies are discovered) is the ideal solution when possible. Health benefits may not appear for several weeks due to allergens remaining in the air and settled dust. If pets stay or are introduced anyway:

  • Keep them out of bedrooms and isolate them in rooms with hard surfaces that can be washed regularly.
  • Bathe cats every week and dogs twice monthly to decrease allergen buildup in dust. Wash rugs pets lie on every week or two.
  • Consider male castration to reduce allergen production since male cats shed more allergen than females.
  • Replace carpets with bare flooring if possible since carpets accumulate pet allergens much faster than bare floors.
  • Vacuum wall-to-wall carpets using a HEPA filter with double-thickness bags.
  • Damp-mop hard surfaces to remove 90% of surface pet allergens.
  • Frequently wash bedding, clothing and other materials that come in contact with pet allergens.
  • Use air cleaners to reduce cat and dog allergen levels where pets spend time.

Often found in schools, office buildings and urban areas, cockroaches are common triggers for asthma and allergic rhinitis. Allergens can come from cockroach body parts, feces and other secretions.

  • Exterminate cockroaches with chemicals, roach traps and baits.
  • Clean up thoroughly after extermination.
  • Seal cracks and other entry points.
  • Remove water sources.
  • Clean kitchen after cooking.
  • Store food (including pet food) in sealed containers.
  • Wash dirty dishes immediately.
  • Restrict meals and snacks to one or two areas in your home.
  • Keep trash in tightly covered cans and remove it daily.
  • Get rid of old newspapers, grocery bags, boxes and bottles.
  • Clean cupboards and cabinets regularly.
  • Encase mattresses and pillows in allergy-proof covers.