Module 7 EnvFactors

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Formaldehyde in your home

--building materials and insulation --cigarette smoking --household products --un‐vented, fuel‐burning appliances •gas stoves, kerosene space heaters•ambient indoor air levels is 0.03 to 0.04 ppm --smoking section in a room can be 0.16 ppm •the most significant sources of formaldehyde are likely to be pressed wood products --made with adhesives containing urea‐formaldehyde (UF) resins --new carpet/cupboards in homes ‐air with 0.16 -0.3 ppm

components of air

-78% nitrogen -21% oxygen -1% argon -0.035% CO2 -0.0001% CO

Nitrogen Oxide (NOx)

-a category of highly reactive gases with nitrogen and oxygen, such as nitrogen dioxide (NO2) and nitrogen monoxide (NO) -produced through combustion, including fossil fuel combustion, when the nitrogen that constitutes almost 80% of air is oxidized --major sources: car and truck engines, electric utilities and industry --also comes from unventilated stoves and heaters, side stream tobacco smoke (indoor air pollution) -major determinant in O3formation

Nitrogen Oxide Health Effects

-can reach deep lungs -irritation of the eyes, nose, and throat at higher concentrations•short‐term decreases in lung function -increased respiratory infections and symptoms for children -in epidemiological studies has been linked to increased morbidity and mortality

hazardous air pollutants (air toxics)

-defined by the Clean Air Act Amendments of 1990 -does not include ALL known hazardous air pollutants and includes some for which hazard level is unknown -these are known to cause cancer or some other significant disease

Health indicators of indoor air pollution

-eye irritation -dry throat -headaches -fatigue -short breath -coughing -nausea -sneezing

Criteria Pollutants

-key outdoor air pollutants defined by the Clean Air Act 1970 -6 specific, ubiquitous pollutants regulated by EPA to protect human health and welfare as they have known health effects

Health effects of lead

-lead can be harmful even at low doses --distributes throughout body; accumulates (mostly) in bone -exposure can damage to the nervous system and kidneys and can interfere with red blood cell formation, reproductive function, and gastrointestinal function --children: neurological ‐behavioral problems, learning deficits, lowered IQ --adults: cardiovascular high blood pressure and heart disease

standard air contains

0.1% to 3% water vapor depending on the temperature

Six "Criterion" pollutants

1. Carbon monoxide (CO) 2. Lead (Pb) 3. Nitrogen dioxide (NOx) 4. Ozone (O3) 5. Particulate matter (PM) 6. Sulfur dioxide (SO2)

4 ways to classify ambient air pollution

Formation Source State Regulation

Formation

How do pollutant molecules form? --primary pollutant: a pollutant that is directly emitted; carbon monoxide (CO) --secondary pollutant ‐formed in the atmosphere through the physical and chemical conversion of precursors; ozone (O3)

Regulation

How is the pollutant regulated? --criteria pollutants: the major pollutants, including O3, NOx, CO, Pb, PM, SO --hazardous air pollutants (aka air toxics): include a number of volatile organic chemicals, pesticides, herbicides, and radionuclides

Source

Is it natural or man-made? --biogenic-natural sources; volatile organic compounds (VOCs) from vegetation, pollen, dust, volcanic gases --anthropogenic‐result of human activity; NOx

standard air may contain traces of

ammonia, sulfur dioxide formaldehyde, carbon monoxide, iodine, sodium chloride, and particular matter such as dust and pollen

Temperature inversion

an atmospheric layer where the temperature increases with height Temperature inversion9

air pollution/air quality

degree of pollution in clean air

standard air

dry atmosphere air found in rural areas or over the ocean far from air pollution sources

Lead (Pb)

historically lead in ambient air came from leaded fuel -lead was added as an anti‐knocking agent -most countries have already phased out leaded gasoline -non‐airborne sources of lead, such as ingestion of leaded paint, are now a larger health concern than airborne lead -other sources: smelters, metal processing, battery recycling centers, waste incineration, contaminated soil (dust)

Carbon Monoxide (CO)

s a colorless, odorless, tasteless, non‐irritating gas (hard to detect) produced from the incomplete combustion of fossil fuels -gasoline, natural gas, oil, coal, tobacco, and other organic materials -toxic to all forms of aerobic life -motor vehicles are major source

State

what is the physical form? -gases -particles --aerosol: relatively stable suspension of solid particles or liquid droplets in a gaseous medium

Formaldehyde & FEMA trailers

•140,000 FEMA trailers were used-meant to be temporary housing --2005 Katrina along Gulf Coast --Hurricane Andrew, Rita, and gulf oil spill •as early as 2006 FEMA workers complained of various symptoms, consistent with formaldehyde exposure -FEMA suppressed information and further testing citing liability issues and hindering rescue efforts (>5X concentration found in the average home) •Sierra Club pushed the EPA and CDC to investigate the thousands of complaints --Sierra Club found levels of 0.34 ppm in 44 trailers they tested

A brief history of air pollution events in USA

•1948 -Donora, PA: pop. 14,000 --6 day temperature inversion blocks dispersal of pollution from zinc and blast furnaces •1,400 seek medical attention (10% of town) •600 become ill •20 die

A brief history of air pollution events in USA

•1954 -Los Angeles, CA --in an especially dense smog, 2,000 car accidents in a single day from decreased visibility --students at USC watched a tie change color due to pollutants in the air, which reacted with dye in the tie

A brief history of air pollution events in USA

•1966 -New York City, NY --3 day temperature inversion over Thanksgiving was blamed for the deaths of 168 people •1969 -Gary, IN and East Chicago, IL --same weekend Neil Armstrong walked on moon, high levels of SO2 lead to acid rain so strong it burned lawns, destroyed tree leaves and caused birds to loose their feathers •1970 -the first Earth Day •1978 -Wheeling, WV --acid rain of pH 2 fell (5,000 times more acidic than normal)

Defining indoor air quality...

•Acceptable IAQ (ASHRAE*) "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 exists for chronic-low level exposures of indoor contaminants !!!

FEMA complaints

•FEMA resisted testing for years •angry activists; many complaints •CDC finally tested in winter 2008 -500 trailers --found most units registered high levels of formaldehyde --emitted from plywood and other construction materials --poor ventilation played a major role •CDC recommended families with children, the elderly and those with chronic diseases like asthma should move out of the temporary trailers as soon as possible --spend as much time outdoors, open windows •FEMA began auctioning off trailers as "scrap" in 2008 --meaning not fit for human habitation

Current situation in Birmingham

•First time in 30 years EPA reports Birmingham in attainment of the six primary air quality standards -Carbon Monoxide -Lead -Nitrogen Dioxide -Ozone -Particle Pollution -Sulfur Dioxide

Impacts of pollution in Victorian England

•In 1851 50% of Great Britain lived in cities --first country in history to achieve this --cities/towns offered better chance of employment and higher wages than the countryside --but the countryside was healthier

Public health emergency in Birmingham

•November 16: particulate matter counts hit 771 mcg/m3 •G.A.S.P. organized protests and demonstrations •State, local health officials ask federal government for help •EPA stepped in and the pollution was ordered to stop for two days

PRE‐CLEAN AIR ACT BIRMINGHAM

•Strong coal and steel industry built Birmingham •One of the most polluted cities in the nation •1970 -Clean Air Act passed •Week of November 15th, 1971 •Public health crisis •EPA arrives

China's Industrial Revolution... more bad air

•World Bank: --16 of the world's 20 cities with the worst air are in China --1% China's 560 million city dwellers breath air considered safe by EU standards •coal is the number one source of air pollution --80% of its electricity and 70% of its total energy is from coal --much of it polluting high‐sulfur coal- -~6 million tons is burned every day •smog‐filled cities are ringed with heavy industry, metal smelters, and coal -‐fired power plants •air pollution and smog in Beijing and Shanghai are sometimes so bad that the airports have shut down because of poor visibility •air quality in Beijing is 16 times worse than NY City •the northeast industrial town of Benxi is so polluted that it once disappeared from satellite photos --its residents have the highest rate of lung disease in China

Volatile organic compounds (VOCs)

•a category of organic chemicals with a high vapor pressure --readily evaporate at normal temperature and pressure --benzene, chloroform, formaldehyde, isoprene, methanol, and hundreds of additional compounds •originate from --natural sources (primarily vegetation such as oak and maple trees) --industrial processes: chemical processing; use of solvents; power generation; transportation including motor vehicles and off‐road transportation sources such as aircraft, construction equipment, and lawn mowers •VOCs are precursors of ozone but also have independent health effects, including irritation of the respiratory tract, headaches, and carcinogenicity

Radon

•a colorless, odorless gas that occurs naturally by the decay of radium and uranium --very high in soils that are rich in granite, shale, phosphate and pitchblende, although most soils do not contain amounts high enough to be dangerous --outside, radon dilutes in the open air and is harmless, but accumulates in enclosed spaces like basements and crawl spaces •estimated that the average person receives 55% of their annual ionizing radiation from indoor radon --estimated to cause 21,000 lung cancer deaths a year --2ndleading cause of US lung cancer deaths

Sulfur Dioxide (SO2)

•a gas that is produced from the combustion of sulfur -‐containing fuels and materials, such as coal and metal ores --power plants are the major source-removal of sulfur from fuels before burning prevents SO2 formation •SO2can be converted to sulfuric acid -‐contributes to acid rain, which harms vegetation, wildlife and other materials •also contributes to the formation of particulate matter

Particulate Matter (PM)

•a generic class rather than a particular, individual pollutant with a specified chemical structure •PM includes solid or liquid particles suspended in air, regardless of their chemical composition •the composition of PM differs by geographic area and can vary with season, source, and weather --Eastern US: PM has high sulfate content --Western US: PM has high nitrate content --the particles can also carry on them other contaminants, and can be a vehicle by which other toxins can reach the depths of the lung

Formaldehyde

•a pungent, flammable, colorless gas •commonly used in water solution as a preservative and disinfectant •a basis for major plastics, including durable adhesives •used to bond plywood, particleboard, carpets and fabrics --contributes to "that new house smell" •also a by product of combustion --tobacco smoke --vehicle exhaust --fumes from furnaces, fireplaces and wood stoves

Air toxics

•also known as hazardous air pollutants (HAP) •includes mostly organics, metals, etc. •known or suspected to cause cancer or other serious health effect•EPA how has 187 pollutants on the HAP list •sources include cars, trucks, buses, industry, power plants-biogenic sources includes volcanoes, forest fires

Generators/sources of indoor air pollution

•coal, gas, oil, wood -combustion products from these •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; 2ndhand smoke) •moisture -growth of molds, other biological contaminants

Ozone (O3)

•colorless, insoluble gas •secondary pollutant •formed in troposphere through complex, nonlinear chemical reactions •precursors include NOx, volatile organic compounds (VOCs) in the presence of sunlight

Biological contamination

•common biological contaminants include molds, mildew, viruses, bacteria, dust mites, cockroaches, pollen, animal dander, and cat saliva --most of these are strong allergens --can weaken the immune system and aggravate asthma --"toxic molds" can release mycotoxins -often inhaled but can be ingested or absorbed through skin •headaches, memory loss, immune suppression, fatigue •the major threat to the biological contaminant of the home is moisture --damp carpets (basements), high humidity in south

"Big Smoke" -1952 Great Fog in London

•considered the worst air pollution event in the history of Great Britain •Friday 5 Dec 1952 -Tuesday 9 Dec 1952 --very cold and no wind --dispersed when weather pattern changed •initially no one thought much of it •medical reports in the ensuing weeks reported 4,000 deaths and over 100,000 illnesses •more recent research indicates 10,000 to 12,000 deaths

Microbial agents and molds

•endotoxins --respiratory reactions •mycotoxins --ingestion and inhaled •allergic reactions •Leviticus 14:33‐45 (Frumkin, xxii‐xxiii)

Other air toxics

•hundreds of other ambient air pollutants exist •include hydrochloric acid, captan, parathion, naphthalene, biphenyl, vinyl bromide, methyl bromide, dioxin, and cadmium•exposure to these pollutants can occur through inhalation, but they also enter other environmental media such as water and food •health effects include damage to the neurological, immune, respiratory, and reproductive (for example, reduced fertility) systems, as well as developmental problems and some cancers

Impacts of pollution in Victorian England

•in a city of 100,000 residents or greater: --1820s baby: life‐expectancy of 35 years --1830s baby: life‐expectancy of 29 years •comparing a 1850s dirty city to a rural market town: --Liverpool -life‐expectancy of 26 years --Okehampton-life‐expectancy of 57 years

Particulate matter health effects

•increased hospital and emergency room admissions•respiratory symptoms, decline in pulmonary function •susceptible populations include people with underlying cardiovascular and respiratory diseases •time‐series studies indicate acute exposures associated with increased mortality •longitudinal studies indicate chronic exposures also associated with increased mortality

Radon detection

•indoor radon concentrations are measured in pCi/L --purchase alpha track detectors to measure -ambient levels are 0.4 pCi/L --average home is 1.3 pCi/L --4 pCi/L or above calls for action ‐ 6% of US homes >4 -->20 pCi/L is a serious concern and requires abatement •mitigation/abatement --basement ventilation --sealing cracks, joints, walls, etc.

London's "Pea Soupers"

•industrial revolution impacted air •steam power from burning coal and wood or coal fires to heat homes released particulates •particles combine with mist/moisture from the Thames river •higher levels of pollution during winter months

Sulfur dioxide health effects

•is highly soluble in water, so most inhaled SO2 is absorbed by the mucous membranes of the upper airways with little reaching the lung (scrubbed) --it an immediate irritant and easy to detect •SO2exposure has been associated with reduced lung function, bronchoconstriction (increased airway resistance), respiratory symptoms, hospitalizations from cardiovascular and respiratory causes, eye irritation, and adverse pregnancy outcomes •linked to increased morbidity and mortality, although difficult to establish causality because it occurs with PM

Air exchange rate

•is the rate at which outdoor air replaces indoor air •when there is little infiltration, natural ventilation, or mechanical ventilation, the air exchange rate is low and pollutant levels can increase --average American home is 0.7 to 1 per hour-tightly sealed homes can be 0.2 per hour •in buildings, before 1973 were required to have 15 ft3/min (CFM) per person of fresh air; now only required to have 5 CFM --may be insufficient to provide a safe and healthy work environmentAir exchange rate

Growing problem of indoor air quality (IAQ)

•justifiable concerns over energy conservation have lead to the construction of homes and buildings that allow much less natural air flow (or offer fewer air exchanges) --thick insulation, triple‐glazed windows, magnetically sealed doors •the overall effect then is to retain and accumulate air toxins in the home (indoors)

Mercury (hg)

•naturally occurring, but can be released into the atmosphere, soil, or water through human activities •mercury commonly contaminates coal --coal‐fired power plants are largest US source of airborne Hg •exposure can occur through inhalation, skin contact, or ingestion, and the health effects of mercury depend on its chemical form •can be deposited into water bodies and consumed by fish, presenting the problem of exposure through food intake

Mold remediation problems

•no exposure limits available for mold •results of sampling are limited due to lack of comparable levels that will induce a measurable effect --lack of a reference value •visual inspection-cannot identify specific types very well •removal of affected surfaces •remediation of causes‐moisture control

Particulate matter sizes

•particles are generally categorized according to their size, pretending it is spherical --PM2.5-2.5 microns (m) in diameter --PM10-10 microns (m) in diameter --Nanoparticles: one dimension is no more than 10 nm

Ozone Health effects

•short‐term exposure in healthy adults associated with --temporarily decreased lung function (bronchoconstriction) --acute epithelial injury --inflammation-increased respiratory symptoms, such as coughing and wheezing --asthmatics are particularly susceptible to health problems associated with ozone exposure

Common health effects of formaldehyde

•small amounts of formaldehyde are harmless but it is an irritating and toxic gas in significant concentrations •symptoms of overexposure to include: -irritation to eyes, nose and throat -persistent cough and respiratory distress -skin irritation -nausea -headache -dizziness

Health indicators of indoor air pollution...

•some acute effects are similar to those from colds or other viral diseases so it can be difficult to determine if the symptoms are a result of exposure to indoor air pollution •it is important to pay attention to the time and place symptoms occur --if the symptoms fade or go away when a person is away from home, an effort should be made to identify indoor air sources that may be possible causes --inadequate supply of outdoor air, increased heating or high humidity conditions can increased acute symptoms

Building‐related illnesses (BRI)

•this term is used when well‐defined illnesses occur in a building, and, they can be traced to specific building problems •well‐defined illnesses often include: -asthma -hypersensitivity pneumonitis •inflammation of the lung tissue -humidifier fever -Legionnaire's disease --caused by a bacteria, Legionella

The public health importance of indoor air

•typical urbanites spend an average of 90% of their time indoors •some at‐risk subgroups spend nearly all their time indoors --elderly, very young, and chronically ill --the most susceptible have the most exposure •previous studies focused almost exclusively on ambient air but evidence now suggests that indoor air is often more polluted than ambient air --and poses a greater health risk

Ventilation and indoor air pollution

•ventilation is an effective way to reduce indoor concentrations of contaminants •three major ways air enters a building: 1. Natural Ventilation- outdoor air flows through opened windows and doors 2. Infiltration- outdoor air flows into the house through openings, joints, and cracks in walls, floors, and ceilings, and around windows and doors 3. Mechanical Ventilation- air is drawn out of the house with vented fans and air exchange systems

Sick building syndrome (SBS)

•when a number of occupants of a given building display acute symptoms without a particular pattern and the varied symptoms, cannot be associated with a particular source the phenomenon is often referred to as SBS •subjective symptoms, rarely associated with objective clinical findings -typically present in some occupants of all buildings at some time •attributed to exposure to VOC, low relative humidity, endotoxin, house dust, inadequate supplies of fresh air-may not be caused by indoor air ‐may be related to: psychological stress, inadequate lighting, excessive heat or cold, noise

Magnitude of poor indoor air quality

•with the exception of ozone (O3) and sulfur dioxide (SO2), all air pollutants regulated under US laws occur at higher concentrations indoors than out‐of‐doors •the EPA now classifies Indoor Air Pollution among the Top 5 Environmental Risks to Public Health


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