Air hygiene and management Global warming, depletion of the ozone layer, outdoor and indoor air pollution
Human ecology • Human ecology is an interdisciplinary science studying the two-way relationship of humans and their natural, social and built environment. • It is interdisciplinary because it relies on the use of the following sciences: geography, sociology, psychology, anthropology, zoology, epidemiology, public health, home economics, and natural ecology among others.
The two-way relationship Global warming, climate change, depletion of the ozone layer, weather fronts
Global warming • Global warming is a term used to describe the rise of mean global temperature experienced in the past decades. This process is caused by the increasing concentration of green house gases. • The main effect of global warming is the changing patterns of the climate. • It also leads to major changes in the weather ( not only in temperature but in precipitation, wind patterns as well).
Climate vs. weather • Climate: the composite or generally prevailing weather conditions of a region, as temperature, air pressure, humidity, precipitation, sunshine, cloudiness, and winds, throughout the year, averaged over a series of years. • Weather: the state of the atmosphere with respect to wind, temperature, cloudiness, moisture, pressure, etc.
Climate zones
Greenhouse gases • Gases that are able to trap heat in the atmosphere are called greenhouse gases. Green house gases are not necessarily harmful. Without them, the global mean temperature on the planet would be below zero. Extreme levels on the other hand may have adversary effects on human health. • The most important green house gases are the following: • Carbon dioxide • Methane • Nitrous oxide
Source of greenhouse gases • Carbon dioxide (CO2): from burning fossil fuels, solid waste and wood products. • Methane (CH4): from production and transport of coal, natural gas, oil; and livestock and other agricultural practices. • Nitrous oxide (N2O): from agricultural and industrial activities.
Carbon dioxide emmission
Methane and livestock • There are both natural and human sources of methane emissions. • The main natural sources include wetlands, termites and the oceans. Natural sources create 36% of methane emissions. • Important human sources come from landfills, livestock farming, as well as the production, transportation and use of fossil fuels. Human-related sources create the majority of methane emissions, accounting for 64% of the total
Effect of greenhouse gases
Environmental impact of climate change
Possible impact on human health
Questions 1. What impact will changed seasonality patterns and characteristics have on the occurrence of certain infectious diseases? 2. What impact will climate change have on the occurrence of malaria?
Answer to question No.1 • Increased incidence of GI infections • Increased incidence of infectious diseases that are spread by certain vectors (e.g. ticks) • Decreased incidence of upper respiratory tract infections. • Appearance of certain diseases not typical of the area.
Malaria and climate change • In many temperate areas, such as western Europe and the United States, economic development and public health measures have succeeded in eliminating malaria. However, most of these areas have Anopheles mosquitoes that can transmit malaria, and reintroduction of the disease is a constant risk. • Malaria doesn’t spread: • • • •
At very high altitudes During colder seasons in some areas In deserts (excluding the oases) In some countries where transmission has been interrupted through successful control/elimination programs.
Global distribution of Anophales species
Malaria and climate change • Temperature is particularly critical. For example, at temperatures below 20°C (68°F), Plasmodium falciparum (which causes severe malaria) cannot complete its growth cycle in the Anopheles mosquito, and thus cannot be transmitted. • Colder temperature is crucial in this regard by stopping Plasmodium’s growth cycle.
Risk of transmission in 2020 compared to 1990
Depletion of the ozone layer • Ozone is a triatomic molecule that consists of three oxygen atoms. • The ozone layer (a portion of the stratosphere with a higher concentration of ozone, from two to eight ppm) is beneficial because it prevents damaging ultraviolet light from reaching the Earth's surface, to the benefit of both plants and animals.
Role of CFCs • A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, and fluorine. It is produced as a volatile derivative of methane and ethane. • Many CFCs have been widely used as refrigerants, propellants, and solvents. • The manufacture of such compounds has been phased out by the Montreal Protocol because they contribute to ozone depletion in the upper atmosphere
Effects of the ozone hole
Effect of the Montreal Protocol on the abundance of effective stratospheric chlorine
Air pollution Definitions , sources, effects, smog, pollen allergy, indoor pollution
Definition of air pollution • Air pollution is the introduction of chemicals, particulates, or biological materials into the atmosphere that cause discomfort, disease, or death to humans, damage other living organisms such as food crops, or damage the natural environment or built environment.
Composition of air
Air pollution can be: 1. Natural: dust from natural sources, for example: smoke and carbon monoxide from wildfires, volcanic activity, methane, and radon. 2. Anthropogenic: from households, industry, agriculture and transport, mostly related to burning different kinds of fuel Or 1. Outdoor 2. Indoor
Dynamics of air pollutants • Emission: emission of pollutants from source (measured in grams/hour). • Transmission: physical and/or chemical transformation of emitted pollutants in the environment. • Immission: concentration of pollution that is present in human environments at 2m height (measured in mg/m3 or µg/m3).
Sources of air pollution • The three main sources of outdoor pollutants can be grouped as follows: • mobile sources • point sources • non-point source
Mobile sources • Mobile sources: The most important mobile sources are vehicles and off-road equipment (such as boats, airplanes, lawn mowers, leaf blowers, and other agricultural and construction equipment). • The gases usually contain the following: • • • • •
Carbon Monoxide (CO), Particulate Matter (PM), Nitrogen Dioxide (NO2), Ozone (O3) and Volatile Organic Compounds (VOC).
Volatile Organic Compounds (VOC) • Volatile organic compounds (VOCs) are emitted as gases from certain solids or liquids. • VOCs include a variety of chemicals, some of which may have short- and long-term adverse health effects. • Concentrations of many VOCs are consistently higher indoors (up to ten times higher) than outdoors. VOCs are emitted by a wide array of products numbering in the thousands. • Examples include: paints and lacquers, paint strippers, cleaning supplies, pesticides, building materials and furnishings, office equipment such as copiers and printers, correction fluids and carbonless copy paper, graphics and craft materials including glues and adhesives, permanent markers, and photographic solutions.
Point and nonpoint source • Point source of air pollution: Point sources are usually caused by factories and industrial facilities like chemical plants, steel mills, manufacturing plants, power plants, and hazardous waste incinerators. • Nonpoint source of air pollution: Nonpoint source air pollution is smokestacks or car tailpipes. Although these pollutants originate from a point source, the long-range transport ability and multiple sources of the pollutant make them a nonpoint source of pollution. Nonpoint sources contribute to over 50% of all particulate matter (PM) emissions, which is higher than point or mobile sources. They also emit Volatile Organic Compounds (VOC) and nitrogen dioxide (NO2) emissions, which contribute to the formation of ground-level ozone.
Particulate matter • Particulate matter (PM) is an umbrella-term used to describe the very fine particles and droplets found in the air. The number after PM, e.g. PM10, shows the diameter of the particle given in micrometer. • PM categories: • PM-10 • PM 2.5-10 • PM <2.5
Size matters • The larger particles are less dangerous because they are too big to enter the airways. • Inhalable coarse particles, such as those found near roadways and dusty industries, are larger than 2.5 micrometers and smaller than 10 micrometers in diameter. Particles that are smaller than 10 micrometers (PM 10) generally pass through the throat and nose and enter the lungs • Fine particles, such as those found in smoke and haze, are 2.5 micrometers in diameter and smaller. These particles can be directly emitted from sources such as forest fires, or they can form when gases emitted from power plants, industries and automobiles react in the air (VOC). These are the most dangerous particles because they accumulate in the lungs.
Ultrafine particles (UFPs) • UFPs are particulate matter of nanoscale size. • Regulations do not exist for this size class of ambient air pollution particles, which are far smaller than the regulated PM10 and PM2.5 particle classes and are believed to have several more aggressive health implications. • In the lungs they have the ability to penetrate tissue and undergo interstitialization, or to be absorbed directly into the bloodstream. • Exposure to UFPs, even if components are not very toxic, may cause oxidative stress, inflammatory mediator release, and could induce heart disease, lung disease, and other systemic effects n those classes of larger particulates
Source of ozone • Ground level ozone is not emitted directly into the air, but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. • Emissions from industrial facilities and electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents are some of the major sources of NOx and VOC.
Source of nitrogen dioxide • Nitrogen dioxide forms when fuel is burned at high temperatures, and come principally from motor vehicle exhaust and stationary sources such as electric utilities and industrial boilers. • It is a strong oxidizing agent that reacts in the air to form corrosive nitric acid, as well as toxic organic nitrates. • It also plays a major role in the atmospheric reactions that produce ground-level ozone (or smog).
Effects of air pollutants
Source of sulfur dioxide and effect • About 99% of the sulfur dioxide in air comes from human sources. • The main source of sulfur dioxide in the air is industrial activity that processes materials that contain sulfur, eg the generation of electricity from coal, oil or gas that contains sulfur. • Some mineral ores also contain sulfur, and sulfur dioxide is released when they are processed. In addition, industrial activities that burn fossil fuels containing sulfur can be important sources of sulfur dioxide • Sulfur dioxide affects human health when it is breathed in. It irritates the nose, throat, and airways to cause coughing, wheezing, shortness of breath, or a tight feeling around the chest. The effects of sulfur dioxide are felt very quickly and most people would feel the worst symptoms in 10 or 15 minutes after breathing it in.
Outdoor air pollution - caused deaths • WHO reports that in 2012 around 7 million people died - one in eight of total global deaths – as a result of air pollution exposure • Main causes of death are: • • • • •
40% ischaemic heart disease; 40% stroke; 11% chronic obstructive pulmonary disease (COPD); 6% lung cancer; and 3% acute lower respiratory infections in children.
Air quality guidelines • PM2.5: 10 µg/m3 annual mean; 25 µg/m3 24-hour mean • PM10: 20 µg/m3 annual mean 50 µg/m3 24-hour mean • Ozone: 100 µg/m3 8-hour mean • NO2: 40 µg/m3 annual mean; 200 µg/m3 1-hour mean • SO2: 20 µg/m3 24-hour mean; 500 µg/m3 10-minute mean
Smoke and Fog= Smog
London-type smog • London-type smog is relatively rare nowadays with decreasing reliance on coal as a source of energy. London-smog has a historical value. • The 1952 severe smog episode in London was directly linked to a surplus of 4000 deaths and 100,000 illnesses. This proved to the world that pollution has hands on effects on human health.
Los Angeles type smog • Los Angeles (L.A.) type smog is a significant public health problem in specific regions of various developed and developing countries. • The most important factors associated with the occurrence of L.A. type smog are: heavy traffic, high UV irradiation levels, high temperatures and little air movement or temperature inversion (warm air is trapped at ground level instead of rising as normal)
Questions 1. What would you do to decrease air pollution? 2. What should be advised to the general population when a smog alert is called?
Answer to question No.1 • Prevention of the adversary effects of air pollution: Emission and immission limits Continuous monitoring Regular prediction of pollutant levels and information of public Smog-alert plans (coordinating efforts of public health authorities and local municipal governments, decreasing traffic, informing the public to stay indoors etc.) • Reducing biological sources (ragweed etc.) • • • •
Successful policies I. • For industry: clean technologies that reduce industrial smokestack emissions; improved management of urban and agricultural waste, including capture of methane gas emitted from waste sites as an alternative to incineration (for use as biogas); • For transport: shifting to clean modes of power generation; prioritizing rapid urban transit, walking and cycling networks in cities as well as rail interurban freight and passenger travel; shifting to cleaner heavy duty diesel vehicles and low-emissions vehicles and fuels, including fuels with reduced sulfur content;
Successful policies II. • For urban planning: improving the energy efficiency of buildings and making cities more compact, and thus energy efficient; • For power generation: increased use of low-emissions fuels and renewable combustion-free power sources (like solar, wind or hydropower); cogeneration of heat and power; and distributed energy generation (e.g. mini-grids and rooftop solar power generation); • For municipal and agricultural waste management: strategies for waste reduction, waste separation, recycling and reuse or waste reprocessing; as well as improved methods of biological waste management such as anaerobic waste digestion to produce biogas, are feasible, low cost alternatives to the open incineration of solid waste. Where incineration is unavoidable, then combustion technologies with strict emission controls are critical.
Answer to question No.2 • People with respiratory or cardiac disorders should take their medication and minimize strenuous outdoor activity on smog alert days. • Avoid driving where possible. Consider public transport, cycling or walking. • Do not burn off outdoors or light incinerators (most local councils have restrictions on burning off). • If an alternative source of heating is available, don’t use solid fuel heaters. • Check the latest air quality readings and forecasts. • It is also important to make sure that: • vehicles are well maintained • wood heaters are used correctly.
What is the air quality like now? • http://www.idokep.hu/szmog • http://www.kvvm.gov.hu/index.php?lang=2 • http://www.nasa.gov/topics/earth/features/health-sapping.html
Pollen allergy • Pollen: a fine powdery substance produced by the anthers of seed-bearing plants, consisting of numerous fine grains containing the male gametes • Data on the presence and prevalence of allergenic airborne pollens, obtained from both aerobiological studies and allergological investigations, make it possible to design pollen calendars with the approximate flowering period of the plants in the sampling area. • Aerobiological and allergological studies show that the pollen map of Europe is changing also as a result of cultural factors (for example, importation of plants such as birch and cypress for urban parklands), greater international travel (e.g. colonization by ragweed in France, northern Italy, Austria, Hungary etc.) and climate change.
Pollen calendar
Ragweed allergy • Symptoms of ragweed allergy include runny or stuffy nose, sneezing and itchy, watery swollen eyes. Severe allergies can also cause headaches, chronic sinusitis, asthma attacks and impaired sleep. Sleep problems can lead to fatigue, trouble concentrating, and even depression. • Ragweed allergy can also cause oral allergy syndrome (OAS). • Ragweed allergy is a seasonal allergy that sometimes worsens after the sufferer consumes fresh fruits (especially cantaloupe and banana) or vegetables.
Questions • A patient asks you what he should do in order to decrease his allergic symptoms? What can he do if he must be outside?
Answer • Close your windows and outside doors. • Avoid using window and attic fans during pollen season. Use airconditioning to cool your home. • Roll up your car windows when driving. Use the air-conditioning, if you need it. • Dry clothing and bedding in the dryer. Don't hang them outside. • Remember that pets can bring in pollen on their fur, too. Don't allow pets that spend time outdoors in your bedroom.
Answer • Check pollen counts before planning outdoor activities. • Avoid being outdoors in the early morning, when pollen is most widespread. • Wear sunglasses to protect your eyes from pollen. • Have someone else mow your grass. Don't rake leaves during pollen season. If you must do yard work, wear a mask. • Going on vacation? Look for a place where pollen is low, such as the beach, or take your medications with you. • Change your clothing when you come indoors. Shower and wash your hair first.
Indoor air pollution Source and effects
Indoor air pollution and key facts • Around 3 billion people cook and heat their homes using open fires and simple stoves burning biomass (wood, animal dung and crop waste) and coal. • More than 50% of premature deaths among children under 5 are due to pneumonia caused by particulate matter inhaled from household air pollution. • 3.8 million premature deaths annually from noncommunicable diseases including stroke, ischaemic heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer are attributed to exposure to household air pollution.
Most important indoor pollutants • Asbestos containing insulation • Radon gas from the globe’s crust. • Toxic combustion products: ETS (Environmental Tobacco Smoke), CO, CO2, NOX, SOX • Lead (Pb): lead-based paint, water (plumbing), outdoor air, dust • Volatile organic compounds (VOC): formaldehyde, paints, varnishes, solvents, air-fresheners, wood-preservatives, etc. • Biological, allergenic or infectious agents: mold, house-mites, pets and farm animals, rodents, arthropods, pollen, Legionella, M. tuberculosis, E. coli.
Impacts on health • Over 4 million people die prematurely from illness attributable to the household air pollution from cooking with solid fuels. • Among these deaths: • • • • •
12% are due to pneumonia 34% from stroke 26% from ischaemic heart disease 22% from chronic obstructive pulmonary disease (COPD), and 6% from lung cancer.
What can you do to decrease indoor pollution? • Ventilate home in the morning and before going to sleep by simply opening the windows or installing a ventilating system. • Ventilate your home after cooking inside.
Sick building syndrome • Term that refers to a set of symptoms that affect a large number of building occupants during the time they spend in the building and diminish or go away during periods when they leave the building. • Cannot be traced to specific pollutants or sources within the building.
Thank you for your attention!
