Lecture 4 Part 1 Air Pollution PDF

UNIT - 4 Environmental Pollution and Health Dr. Sunita Varjani, PhD, FSAB Sr. Associate Professor, School of Engineering Jointly with SoHST Cabin 3, Block B, 2nd Floor, Hubble UPES, Dehradun, India Adjunct Professor: Korea University, Seo...

UNIT - 4 Environmental Pollution and Health Dr. Sunita Varjani, PhD, FSAB Sr. Associate Professor, School of Engineering Jointly with SoHST Cabin 3, Block B, 2nd Floor, Hubble UPES, Dehradun, India Adjunct Professor: Korea University, Seoul, Republic of Korea Contact: +91-9909828684 (Mobile); 0135-2770137 (Ext: 1321) (Office) Highly Cited Researcher 2022 (Top 1% in the world), Clarivate’s Web of Science Highly Cited Researcher (Top 2% in the World), Stanford University and Elsevier Citation Report (2019-Continue) Important Air Pollutants Volatile Organic compounds (VOCs) Peroxy acetyl nitrate (PAN) Polycyclic aromatic hydrocarbons (PAHs) Persistent organic pollutants (POPs)  Volatile Organic compounds (VOCs) VOCs are substances that evaporates at room temperature and are commonly found in household products and building materials. Volatile – something that can change quickly Organic – anything that contains the element carbon Compound – having more than one element  Here are some common smells most of us LOVE that are actually a result of potentially harmful VOCs Fuels New Car smell Glues Cleaning Products New Air Sneakers Fresheners Paints  HOW VOCs AFFECT HUMAN HEALTH  Health Effects Eye Irritation Throat Irritation Causes Headaches and Dizziness Nose Irritation Visual impairment & Memory loss Health Effects Breathing VOCs can irritate the eyes, nose and throat, can cause difficulty breathing and nausea, and can damage the central nervous system and other organs. Some VOCs can cause cancer. Details on specific health effects of each specific VOC can be found in the Agency for Toxic Substances and Disease Registry Toxic Substances Portal. Outdoors, VOCs can cause similar health effects, but also can react with nitrogen oxides to produce ozone pollution, the nation's most widespread outdoor air pollutant. Peroxy acetyl nitrate (PAN) It is a Secondary pollutant Formed by the reaction of NO2 with VOCs Can form naturally in some environments Health Effects (Humans/Plants) Respiratory and Eye irritants Mutagenic – Skin Cancer Effects growth of plants Blocks stomata opening after getting deposited on leaves Skin Cancer Polycyclic aromatic hydrocarbons (PAHs) Polycyclic aromatic hydrocarbons (PAHs) are widely distributed and relocated in the environment as a result of the incomplete combustion of Organic Matter (fossil fuel combustion). Many PAHs and their epoxides are highly toxic, mutagenic and/ or carcinogenic to microorganisms as well as to higher systems including HUMANS.  Polycyclic aromatic hydrocarbons (PAHs) are hydrocarbons- organic compounds containing only carbon and hydrogen- that are composed of multiple aromatic rings (organic rings in which the electrons are delocalized).  Environmental Effects Mammals can absorb PAHs by various routes e.g. inhalation, dermal contact and ingestion. Plants can absorb PAHs from soils through their roots and translocate them to other plant parts. PAHs are moderately persistent in the environment, and can bio-accumulate.  Persistent organic pollutants (POPs) GLOBAL CONCERN – POPs are of global concern because there is evidence of global transport of these substances by air and water to regions where they have never been produced. Tendency to persist in the environment Bio-accumulate in the food chain Adversely affect human and animal population Harmful Effects Cancer Birth defects Even Deaths INDOOR AIR POLLUTION Around 2.4 billion people worldwide cook using open fires or inefficient stoves fueled by kerosene, biomass (wood, animal dung and crop waste) and coal, which generates harmful household air pollution. Household air pollution exposure leads to noncommunicable diseases including stroke, ischemic heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer. The combined effects of ambient air pollution and household air pollution are associated with 6.7 million premature deaths annually. Adverse Health Impacts of Air Pollutants  Both short- and long-term exposure to air pollution can lead to a wide range of diseases, including stroke, chronic obstructive pulmonary disease, trachea, bronchus and lung cancers, aggravated asthma and lower respiratory infections. Particulate matter (PM10, PM2.5) Particulate matter (PM) is made up of small airborne particles like dust, soot and drops of liquids. The majority of PM in urban areas is formed directly from burning of fossil fuels by power plants, automobiles, non-road equipment and industrial facilities. Other sources are dust, diesel emissions and secondary particle formation from gases and vapors. Coarse particulate matter (PM10, particles less than 10 microns in diameter) is known to cause nasal and upper respiratory tract health problems. Fine particles (PM2.5, particles less than 2.5 microns in diameter) penetrate deeper into the lungs and cause heart attacks, strokes, asthma, and bronchitis, as well as premature death from heart ailments, lung disease and cancer. Studies show that higher PM2.5 exposure can impair brain development in children. Black carbon (BC) Black carbon is one of the components of particulate matter and comes from burning fuel (especially diesel, wood, and coal). Most air pollution regulations focus on PM2.5, but exposure to black carbon is a serious health threat as well. Populations with higher exposures to black carbon over a long period are at a higher risk for heart attacks and stroke. In addition, black carbon is associated with hypertension, asthma, chronic obstructive pulmonary disease, bronchitis, and a variety of types of cancer. Nitrogen oxides (NO and NO2) Nitrogen oxide (NO) and nitrogen dioxide (NO2) are produced primarily by the transportation sector. NO is rapidly converted to NO2 in sunlight. NOx (a combination of NO and NO2) is formed in high concentrations around roadways and can result in development and exacerbations of asthma and bronchitis, and can lead to a higher risk of heart disease. Ozone (O3) Ozone high in the atmosphere can protect us from ultraviolet radiation. But ozone at ground level (where it is part of what is commonly called smog) is a well-established respiratory irritant. Ozone is formed in the atmosphere through reactions of volatile organic compounds and nitrogen oxides, both of which are formed as a result of combustion of fossil fuels. Short-term exposure to ozone can cause chest pain, coughing and throat irritation, while long term exposure can lead to decreased lung function and cause chronic obstructive pulmonary disease. In addition, ozone exposure can aggravate existing lung diseases. Sulfur dioxide (SO2) SO2 is emitted into the air by the burning of fossil fuels that contain sulfur. Coal, metal extraction and smelting, ship engines, and heavy equipment diesel equipment burn fuels that contain sulfur. Sulfur dioxide causes eye irritation, worsens asthma, increases susceptibility to respiratory infections and impacts the cardiovascular system. When SO2 combines with water, it forms sulfuric acid; this is the main component of acid rain, a known contributor to deforestation.  National Ambient Air Quality Standards An air quality standard defines the maximum amount of a pollutant averaged over a specified period of time that can be present in outdoor air without harming public health, and thus, it defines clean air. The Clean Air Act Amendments of 1970 instruct the U.S. Environmental Protection Agency (U.S. EPA) to set primary National Ambient Air Quality Standards (NAAQS) to protect public health, and secondary NAAQS to protect plants, forests, crops and materials from damage due to exposure to six air pollutants. The WHO Global air quality guidelines (AQG) offer global guidance on thresholds and limits for key air pollutants that pose health risks. These guidelines are of a high methodological quality and are developed through a transparent, evidence-based decision-making process. In addition to the guideline values, the WHO Global air quality guidelines provide interim targets to promote a gradual shift from high to lower concentrations. The guidelines also offer qualitative statements on good practices for the management of certain types of particulate matter (PM), for example black carbon/elemental carbon, ultrafine particles, and particles originating from sand and dust storms, for which there is insufficient quantitative evidence to derive AQG levels. Thank you !!!