module 6 - air - ambient air pollution/case studies, indoor air quality/case studies, air policy

SBS vs BRI; identifying poor IAQ

BRI (building related illness) - well-defined illnesses (asthma, hypersensitivity pneumonitis, humidifier fever, Legionnaire's disease) occur in a building and they can be traced to specific building problems SBS (sick building syndrome) - when a number of occupants of a given building display acute symptoms without a particular pattern; cannot be associated with a particular source; subjective symptoms, rarely associated with objective clinical findings identifying poor indoor air quality: eye irritation, dry throat, headaches, fatigue, sinus congestion, sun irritation, shortness of breath, cough, dizziness, nausea, sneezing, nasal irritation

formaldehyde - what it is, common sources, PUH relevance

a pungent, flammable, colorless gas; commonly used in water solution as a preservative and disinfectant; basis for major plastics, by-product of combustion (tobacco smoke, vehicle exhaust, fumes from furnaces, fireplaces, and wood stoves) causes irritation to eyes, nose, throat; persistent cough and respiratory distress, skin irritation, nausea, headache, dizziness

lead

air Pb came largely from leaded fuel - not usually used anymore exposure through ingestion or inhalation distributes throughout the body, but mostly accumulates in bones adversely affects many organs, but effects seen mainly as neurological problems (children: behavioral problems, learning deficits, lowered IQ), hearing loss, attention deficit, increased irritability, and kidney damage; CV problems (adults: high blood pressure and heart disease) does not have a threshold for each of its outcomes - no point at which a measurable adverse outcome cannot be observed

why indoor air quality and not pollution

air in which there are no known contaminants at harmful concentrations as determined by recognized authorities and with which a substantial majority (80% or more) of the people exposed do not express dissatisfaction no standards exist for chronic-low level exposures of indoor contaminants

sources of ambient air pollution

biogenic (natural sources); VOCs, pollen, dust, volcanic gases anthropogenic - human activity, NOx

radon - sources, what it is, PUH relevance how it enters homes, how to reduce exposures

colorless, odorless gas that occurs naturally by the decay of radium and uranium estimated that the average person receives 55% of their annual ionizing radiation from indoor radon causes 21,00 lung cancer deaths/year - 2nd leading cause of US lung cancer deaths can accumulate in enclosed spaces like basements and crawl spaces reduce by basement ventilation and sealing cracks, joints, walls, etc

carbon monoxide

colorless, odorless, tasteless, non-irritating gas often produced from the incomplete combustion of fossil fuels toxic to all forms of aerobic life top causes: deforestation and other wildfires, biofuel combustion, road, residential and commercial sector, agriculture waste burning

common sources of indoor air pollutants

combustion from coal, gas, oil, wood cleaning products and pesticides furniture made of pressed wood new carpeting and draperies paints and other materials that off-gas VOCs products for personal care and hobbies; air fresheners cooling and humidification systems radon ETS (environmental tobacco smoke; 2nd hand smoke)

particulate matter

comes from volcanoes, dust storms, forest and grassland fires, living vegetation, sea spray, burning fossil fuels, incinerating wastes, and smelting metals eastern US has high sulfate content, western US has high nitrate content causes decreased lung function, chronic bronchitis, increased respiratory symptoms, cardiac arrhythmias, heart attacks, premature death

regulation of ambient air pollution

criteria pollutants (O3, NOx, SO2, PM, CO, Pb) hazardous air pollutants (VOCs, pesticides, herbicides, radionuclides)

clean air act of 1970

defined outdoor air pollutants - criteria pollutants

pollution

degree of substances in standard air capable of causing harmful effects

clean air act amendments of 1990

does not include ALL known hazardous air pollutants and includes some for which hazard level is unknown 5 main areas: 1. air quality standards 2. motor vehicle emissions and alternative fuels 3. toxic air pollutants 4. acid rain 5. stratospheric ozone depletion

clean air (standard air)

dry atmosphere air found in rural areas or over the ocean far away from air pollution sources 0.1%-3% water vapor/volume (temp dependent) traces: ammonia, sulfur dioxide, formaldehyde, carbon monoxide, iodine, salt; particular matter

molds - identifying molds, how they make us sick; mold remediation issues

endotoxins - respiratory reactions mycotoxins - ingestion and inhaled allergic reactions no exposure limits are available results of sampling are limited due to lack of comparable levels that will induce a measurable effect visual inspection - cannot identify specific types very well removal of affected surfaces remediation or causes - moisture control

health effects of indoor air pollution

eye irritation, dry throat, headaches, fatigue, sinus congestion, sun irritation, shortness of breath, cough, dizziness, nausea, sneezing, nasal irritation

4 categories of ambient air pollution

formation, source, state, regulation

sulfur dioxide

gas produced from the combustion of sulfur-containing fuels and materials, such as coal and metal ores also comes from volcanoes and hot springs, oil production, coal combustion, chemical manufacturing, and fossil fuel processing and burning highly soluble in water - absorbed by mucous membranes in upper airways reduced lung function, bronchoconstriction, respiratory symptoms hospitalizations from CV and respiratory causes, eye irritation, and adverse pregnancy outcomes

state of ambient air pollution

gases, particles (aerosol) - relatively stable suspension of solid particles or liquid droplets in a gaseous medium

air pollution control act of 1955

identified air pollution as a national problem and announced that research and additional steps to improve the situation needed to be taken

hazardous air pollutants

known or suspected to cause cancer or other serious health effects EPA monitors 187

ventilation

natural ventilation - opened windows and doors infiltration - outdoor air flows into the house through openings, joints, and cracks in walls, floors, and ceilings, and around windows and doors mechanical ventilation - air is drawn out of the house with vented fans and air exchange systems

mercury

occurs naturally but can be released into the atmosphere, soil, or water through human activities exposure can occur through inhalation, skin contact, or ingestion, and the health effects of mercury depend on its chemical form target organs: CNS, kidney, PNS clinical sign: lung irritation systemic effects: kidney - proteinuria, CNS - mood change, PNS - tremors

origins of VOCs

originate from natural sources (vegetation - oak and maple trees) and industrial processes (chemical processing, use of solvents, power generation, transportation) precursors of ozone but also have independent health effects, including irritation or the respiratory tract, headaches, and carcinogenicity

6 criterion (common) pollutants

ozone (O3), nitrogen dioxide, sulfur dioxide, particulate matter, carbon monoxide, lead

air toxics: number, examples, how defined

pollutants known or suspected to cause cancer or other serious health effects 187 volatile organic compounds (VOCs) polycyclic aromatic hydrocarbons (PAHs) heavy metals carbonyl compounds increased risk of cancer or other health effects (damage to immune system, neurological, reproductive, developmental, respiratory, and other health problems)

formation of ambient air pollution

primary pollutant - directly emitted (CO) secondary pollutant - formed in the atmosphere through the physical and chemical conversion of precursors (ozone - O3)

nitrogen oxides

produced throughout combustion; major sources include car engines, electric utilities, and industry causes smog, reduced visibility, global warming, forms acid vapor and particles, and found in acid rain acute toxicity: irritation of respiratory tract, toxic edema, emphysema, increased breathing resistance chronic toxicity: fibrosis, secondary bacterial infections, damage of collagen and elastin fibers

to decrease exposure to organic gases, pesticides, and HAPs, users should:

properly dispose of un-needed products, follow instructions on label and only use in well-ventilated areas, use nontoxic alternatives where possible

air exchange rate

rate at which outdoor air replaces indoor air when exchange rate is low, pollutant levels can increase

National Ambient Air Quality Standards

set by EPA

clean air act of 1963

set emissions standards for stationary sources (power plants and steel mills) - NOT mobile sources of air pollution

ozone

short-term exposure associated with: temporarily deceased lung function, acute epithelial injury, inflammation, increased respiratory symptoms (coughing, wheezing)

important factors to pay attention to for indoor air pollution

the time and place that symptoms occur

FEMA trailer PUH issue

trailers used for hurricane katrina victims found to have high ppm's of formaldehyde

PUH relevance of indoor air quality

typical urbanites spend an average of 90% of their time indoors some at-risk subgroups spend nearly all there time indoors (elderly, very young, chronically ill) previous studies focused almost exclusively on ambient air but evidence now suggests that indoor air may be more polluted than ambient air - poses a greater health risk

magnitude of poor indoor air quality

with the exception of O3 and SO2, all air pollutants regulated under US laws occur at higher concentrations indoors than outdoors indoor air pollution now in the top 4 environmental risks to PH