Indoor Environmental Quality: Health Effects, Asthma, and

Asthma Triggers

John W. Martyny, Ph.D., CIH

Tri-County Health Department

Sources of IAQ Pollutants

Outdoor pollution Indoor pollution Building material off-gassing Inadequate ventilation

Forms of Indoor Pollutants

Particles Liquids Fumes Mists Gases Vapors Physical Agents

Dose Response

The higher the dose the greater the response.

Exceptions: Allergens Carcinogens

Chronic vrs. Acute Effects

Acute Immediately after exposure May disappear quickly

Chronic May appear months or years after initial

exposure Symptoms may slowly appear and not be

reversible.

Examples of specific pollutants

Carbon Monoxide Sources:

forklifts, floor polishers, combustion sources

Health Concerns: headache, fatigue, poor vision, lack of

coordination, CNS problems, coma, death.

Normal Concentration: Less than 10 ppm

Accepted Limits: ACGIH - 25ppm (lower at altitude)

Nitrogen Oxides Sources:

Fossil fuels, welding, outside air

Health Concerns: Upper respiratory irritation, pulmonary edema,

asthmatic reactions.

Normal Concentration: Less than 0.1 ppm

Acceptable Limits: Nitrogen dioxide - 2 ppm

Fibrous Particles Types - Asbestos & Fiberglass Sources:

Insulation, duct lining, etc.

Health Concerns: Dermatitis, respiratory disease, cancer

Normal Concentration: Varies

Acceptable Limits: Asbestos - 0.1 f/cc Fiberglass - 1 f/cc

Formaldehyde Sources:

Insulation, pressed wood prod., textiles, etc.

Health Concerns: Mucous membrane irritation, chest tightening,

asthmatic reactions, cancer.

Normal Concentration: Less than 0.01 ppm

Acceptable Limits: 0.3 ppm

Suspended Particles

Sources: Smoking, printers, building materials

Health Concerns: Eye Irritation, upper resp. irritation, etc.

Normal Concentration: Less than 0.01 mg/m3

Acceptable Limits: 5 - 10 mg/m3

Volatile Organic Compounds Sources:

Glues, carpeting, copy machines, cleaning compounds, paints, etc.

Health Concerns: Odors, headache, mucous membrane irritation,

nausea, dizziness, etc.

Normal Concentration: Not well defined (TVOC = < 1mg/m3)

Acceptable Limits: Varies with compound

Lead Sources:

Lead paint, lead products, indoor firing ranges.

Health Concerns: Children - Decreased learning, neurotoxicity. Adults - neuotoxicity, joint pain, weight loss, CNS

damage

Normal Concentration: <1 ug/m3

Acceptable Limits: < 50ug/sq.ft. floor space

Radon

Sources: Soil, building materials

Health Concerns: Lung cancer

Normal Concentration: 1.5 pci/l

Acceptable Limits: 4 pci/l

Ozone Sources:

Copiers, air cleaners, outside air.

Health Concerns: Upper resp. irrit, pulmonary edema, asthmatic

reactions.

Normal Concentrations: Less than 20 ppb

Acceptable Limits: 50 -100 ppb

Environmental Tobacco Smoke

AKA

Passive Smoking Involuntary Smoking Side-Stream Smoke Secondhand Smoke

ETS Components

Composed primarily of sidestream smoke and exhaled mainstream smoke

complex mixture of >4,000 compounds Contains: > 40 carcinogens (e.g., benzene, nitrosamines,

polycyclic aromatic hydrocarbons),

respiratory irritants (e.g., ammonia, formaldehyde,

sulfur dioxide),

reproductive toxicants (e.g., carbon monoxide,

nicotine).

Why Focus on Children?

Need is the greatest Children particularly

susceptible Exposure is involuntary Most children of smokers are exposed in the home

What’s the Problem 27% of homes with children age 6 &

under, regularly allow smoking 9-12 million children under 5 are

exposed in the home 38% of children 2 mos. - 5 yrs are

exposed in the home

What’s the Problem

Up to 1 million children have their asthma worsened (costing $200 million annually)

Estimated 700,000 - 1.6 million doctor

visits for ear infections 150,000 - 300,000 cases of

bronchitis and pneumonia

annually in toddlers

Lower Respiratory Tract Infections

e.g., pneumonia, bronchitis, bronchiolitis very strong, consistent evidence for infants

and young children (up to about 3 years) strongest effect from maternal smoking, but

also evidence from paternal smoking increased risks of about 50 to

100% for young children;

higher for young infants

Respiratory Symptoms

Chronic cough, phlegm, and wheezing strong consistent evidence, especially

for preschool children increased risks of about 20 to 40% Asthma exacerbations

Middle Ear Disease

strong evidence for acute and chronic middle ear disease

fluid in the middle ear is the most common reason for operations in young children in the U.S.

increased risks of up to

about 20 to 40%

Other Health Effects

Decreased lung function – small (<10%), but significant reduction in lung growth/function

Decreased Fetal Growth– consistent evidence of small effect for nonsmoking mothers during pregnancy

Emerging Science

Cognitive and Behavioral Effects– Poor performance in school and standardized and behavioral tests

Cardiovascular Effects– Adults and Children (stronger for adults)

Childhood Cancer– Suggestive evidence of leukemia & brain tumors

SIDS - Suggestive evidence of association

Conclusions

Strong international scientific consensus that ETS exposure causes increased risk of a variety of health effects in children

Increased risks of common ailments, coupled with widespread exposure, result in large public health impacts and financial costs

ETS exposure and resultant health effects in childhood may also increase the risk of further adverse effects in adulthood

Hypersensitivity Illnesses

Types of Hypersensitivity Illnesses

Allergies Allergic Rhinitis Hypersensitivity Pneumonitis Asthma

Allergies

An immune-mediated state of hypersensitivity that results from exposure to an allergen.

Hypersensitivity is an exaggerated or inappropriate immune response.

Examples: hay fever, food allergies, horse serum

Common Indoor Allergens

Pollen grains and fungal spores Bacteria, protozoa, and fungi House dust mites Cockroaches Birds Mammals

Immune System Responses Depend Upon

Source material Host factors Duration of exposure Intensity of exposure

Source Material

Can it be allergenic? Will it penetrate into the lungs? Will it be removed quickly? Have there been prior exposures?

Antigens

Must be recognized by the body as foreign.

Typically are relatively large molecules or are attached to larger molecules.

Plant and animal proteins are potent antigens. Chromium, beryllium, etc.

Single amino acids and simple sugars are usually not antigenic.

Host Factors

??????? Is the person atopic? Do other family members have

hypersensitivity diseases? IgM, IgG, and IgE levels. IgE is primarily responsible for release of

histamine (Clinical allergy symptoms).

Duration and Intensity of Exposure

Will the allergen be in the lungs for a long period of time?

Can the respiratory tract remove the material? Will the exposure be constant?

Allergic Rhinitis

Prevalence rate of 10% - 20% of population.

Sympt. - Runny and congested nose, inflamed throat and eyes, sneezing, etc.

Caused by IgE mediated inflammation and histamine release.

Allergens - dust mites, fungi, pollen, cats and dogs.

Hypersensitivity Pneumonitis

Caused by repeated or continuous exposure to antigenic substances.

Flu symptoms - chills, fever, malaise, cough, difficulty breathing.

Granulomatous lesions within the lung. Easily misdiagnosed.

Sarcoidosis

Hypersensitivity Pneumonitis (Cont)

Frequently named after exposure: pigeon-breeders disease, farmers lung.

Attack rate may vary from 15% to >50%.

Examples: Hot tubs, Pools, Mold exposure.

Asthma

www.epa.gov/iaq/asthma/index.html

What is Asthma? Chronic Inflammatory Disorder of Airways Characterized by:

Recurrent Episodes of Airflow Limitation Airway constriction

- Usually Reversible * Spontaneously, or * with Appropriate Treatment

What Happens During Attack?

Airways Narrow

Mechanism:

- Tightening muscles surrounding airways

- Swelling of inner lining of airways

- Increase in mucus production &/or

inflammation

Asthma Symptoms

Coughing

Wheezing

Chest Tightness

Shortness of Breath

Asthma Facts

Over 27 million Americans have been diagnosed with asthma

Approx. 11 million Americans had at least 1 asthma attack in the past year

On average, 14 people die each day from asthma

Asthma Facts $6.2 billion spent on asthma in 1990 Self-reported prevalence rate increased

75% from 1980-1994 National asthma-related hospitalizations

increased 80,000 between 1979-1980

and 1993-1994

Rise in atopic diseases

Allergies, eczema etc

Atopy [familial tendency to certain hypersensitivities] also on increase

Why? Research is ongoing…

High-Risk Populations (for asthma)

Children Low-income, urban residents Minorities Those with hereditary predisposition Allergic individuals

Emerging Science

Overweight = Possible risk factor

# of Siblings = Possibly protective

# of Early Life infections = Possibly

protective

Children and Asthma

In 1980, 2.3 million American children had asthma. By 1995, the number of children with asthma had risen to 6 million.

7.3% of children under age 18 have asthma Asthma is the most common chronic illness in

childhood & the leading cause of missed school days due to chronic illness

Asthma mortality for children is 5X higher than adults

Low-Income, Urban Residents and Asthma

Likely contributing factors:

- poverty

- exposure to higher levels of

allergens & air pollution episodes

- limited access to medical care

Minorities and AsthmaAfrican-Americans Children are 4X more likely to die from asthma than

Caucasian children (in 1995) Children have 3X greater hospitalization rate than

Caucasian children

Some Hispanics Prevalence of asthma is 11.2% in Puerto Ricans

compared to 3.3% for non-Hispanic whites

Hereditary Predisposition and Asthma

Children with one asthmatic parent have ~25% greater risk of developing asthma than children of non-asthmatic parents

Children with two asthmatic parents have ~50% greater risk of developing asthma than children of non-asthmatic parents

Common Asthma Triggers

Allergens

- molds

- dust mites

- cockroaches

- animal dander

- pollens

- foods

Irritants

- ETS

- strong odors

- aerosols

- VOCs

- ozone

- particulate

matter

Common Asthma Triggers Other - viral respiratory infections - emotional expressions (stress, crying, laughing) - changes in weather (cold air, wind, humidity) - exercise - medications - endocrine factors (pregnancy, menstrual cycle, thyroid disease)

EPA Targeted Triggers

Irritants (e.g. ETS) Dust Mites Cockroaches And Rodents Animal Dander Molds