Air Pollution & Human Health Flashcards
Health Impact of Air Pollution
-Threat for people with preexisting CV & lung disease.
-Cigarette smoke, vaping & motor vehicle traffic exhaust act synergistically to aggravate respiratory diseases.
-Association of motor vehicle exhaust & angina pectoris.
-Association of increased level of CO with acute myocardial infraction.
-Low-income & crowded neighborhoods near heavy traffic roads have higher prevalence of asthma.
-High ambient level of PM2.5 is associated with increased number of emergency room visits due to asthma attacks.
Air Pollution & The Respiratory System
-Chronic Obstructive Pulmonary Disease (COPD)
-Asthma trigger and/or exacerbation
-Lung Cancer
Chronic Obstructive Pulmonary Disease (COPD)
COPD, a slowly progressive disease of the airways is characterized by a gradual loss of lung function.
In the U.S., the term COPD refers to;
-Chronic Bronchitis
-Chronic Obstructive Bronchitis
-Emphysema
~or a combination of these conditions
COPD Risk Factors in the US
1) Cigarette smoking
2) Pipe, cigar, other types
3) Second-hand smoke
4) Occupational dusts & chemicals
5) Outdoor air pollution adds burden with particles inhaled into lungs. (its role is COPD risk is being studied).
Asthma
Asthma is a chronic disorder of the airways.
~Characterized by reversible airway obstruction & nonspecific bronchial hyper responsiveness.
Asthma Epidemiology
~1.8 million emergency room visits/year
~500,000 hospitalized for asthma/year
~ >5,000 die from asthma/year.
Asthma prevalence, morbidity & mortality are increasing.
Asthma Risk Factors
- Genetic Characteristics
- Environmental exposures that lead a person to develop asthma.
- Environmental exposures that lead a person with asthma to have an attack.
(Residents of places located near border areas, heavy traffic, are four times more likely to suffer from asthma).
Asthma Genetic Characteristics
-Some people have a genetic predisposition to react to certain allergens.
*Susceptibility for development of atopic disease appears to have familial associations & genetic components.
Social, Economical, & Cultural Factors of Asthma:
-Prevalent & severity occurs due to differences in socioeconomic or ethnic groups.
-Poverty: Lack of access to health care, geographic location, heavy traffic, etc.
-Economic, environmental, & cultural factors play a role in the disparities between high- and low-income minority children.
Cardiovascular Disease
Cardiovascular Disease, individuals are at a higher risk when they have preexisting metabolic, heart, or lung disease through the effects of air pollutants.
~Arrhythmias & hypertension may rigger angina, a heart attack, or stroke.
PM & Systemic Inflammation
SLIDE 35
Cardiovascular Effects of PM Exposure
SLIDE 36
Air Pollution & Cardiovascular Disease : Morbidity
-0.3% increase of cardiovascular diseases in hospital admissions with PM levels were higher.
-Inflammation due to Pm is stronger in persons with diabetes, obesity, & hypertension.
-Association between PM & blood pressure (stronger in the presence of roadway traffic)
-Association of motor vehicle exhaust &angina pectoris as well as, CO & acute myocardial infarction.
Chronic Exposure to Air Pollutants & Cardiovascular Disease : Mechanism of Damage of Particulate Matter (PM)
LUNG INFLAMMATION
~ PM inhalation causes lung inflammation
~Generating inflammatory molecules (Cytokines), which leak into circulation..
Chronic Exposure to Air Pollutants & Cardiovascular Disease : Mechanism of Damage of Particulate Matter (PM)
LUNG TO BLOOD
~PM translocate into general circulation generating oxygen radicals, lipid oxidation
~Deposit of oxidated lipids in arterial wall (Atherogensis), vascular disfunction & systemic inflammation.
Cardiovascular Disease: Acute Exposure to Air Polluntants
A study was conducted to investigate the adverse respiratory & cardiologic effects of exposure to roadway emissions in healthy, young, non-obese young adults.
~For every 10ug of PM2.5um, increases of 8% of deaths from lung Ca.
~Even short-term increases of air pollutants is associated with heart attacks, mainly in smokers & second-hand smoke.
Reproductive System
~Traffic pollution is associated with damaged sperm & reduction of fertility in men. (Less efficient in reaching & penetrating the sperm).
~Sperm count, volume, & hormone levels were not different between the study groups.
~Higher blood levels of air pollutants in men exposed to air pollutants.
~Wives of men heavily exposed to traffic air
pollutants become pregnant in nearly double
average time of those whose husbands were not
exposed
* Seasonal air pollution affects young men sperm in
terms of its motility, morphology (head shape)
Birth Effects/Outcome
Risk for low birth weight may increase with:
co exposure during 2-5 months.
Particulate Matter <10um in month 2-4 -SO2
PM Translocation into Brain
PM, Soluble & poorly soluble, travel from olfactory mucosa to the olfactory bulb of the brain via olfactory nerve axons.
PM Translocation into the Brain : Route 2
Another possible translocation route is from the mother to fetus via the placenta.
~Immature fetal hematoencephalic brain barrier leaks some pollutants into the brain.
Health impact in correlation to PM Translocation into the Brain
HEALTH IMPACT:
Decreased cognitive function across verbal & nonverbal intelligence & memory.
Air Pollution & Atherogenesis (CIMT) in children that are in Ecuador
SLIDE 46 & 47
