Environmental Biotechnology Lecture Notes PDF

Environmental Biotechnology Prof. Dr. Khadiga Abou-Taleb Prof. of Microbiology, Agric. Microbiology Dept., Fac. of Agric. Ain Shams University E. mail: [email protected] Prof. Khadiga Abou-Taleb  Any visible or invisible particle or gas fo...

Environmental Biotechnology Prof. Dr. Khadiga Abou-Taleb Prof. of Microbiology, Agric. Microbiology Dept., Fac. of Agric. Ain Shams University E. mail: [email protected] Prof. Khadiga Abou-Taleb  Any visible or invisible particle or gas found in the air that is not part of the original, normal composition.  Chemicals added to the atmosphere by natural events or human activities in high enough concentrations to be harmful. Prof. Khadiga Abou-Taleb  with Rapid industrialization Civilization caused human health problems such as ophthalmic, respiratory and cardiovascular diseases Types of treatments of contaminants including microbial bioremediation Prof. Khadiga Abou-Taleb phytoremediation  I-divided into according to their sources Natural pollutants Unnatural pollutants forest fires, pollen, dust man-made; coal, wood and other fuels storm used in cars, homes, and factories for energy II- divided into two categories according to their types Primary Air Pollutant Secondary Air Pollutant Harmful substance that is Harmful substance formed in the released directly into the atmosphere when a primary air atmosphere pollutant reacts with substances normally found in the atmosphere or with Prof. Khadiga other air pollutants Abou-Taleb Prof. Khadiga Abou-Taleb  Major Air Pollutants The most common air pollutants, their possible health effects from exposure, and how to limit or avoid exposure. The common air pollutants are: Particulate matter, ozone (O3), nitrogen dioxide (NO2), carbon monoxide (CO) and sulphur dioxide (SO2) (Table 1 and 2). Prof. Khadiga Abou-Taleb Major Air Pollutants Prof. Khadiga Abou-Taleb  Particulate Material Solid or liquid matter that is suspended in the air. To remain in the air, particles usually must be less than 0.1-mm wide and can be as small as 0.00005 mm. Thousands of different solid or liquid particles suspended in air – Includes: soil particles, lead, asbestos, sea salt, and sulfuric acid droplets Dangerous for 2 reasons – May contain materials with toxic or carcinogenic effects – Extremely small particles can become lodged in lungs Prof. Khadiga Abou-Taleb The size of particles affects their potential to cause health problems: PM10 (particles with a diameter of 10 micrometres or less): these particles are small enough to pass through the throat and nose and enter the lungs. Once inhaled, these particles can affect the heart and lungs and cause serious health effects. PM2.5 (particles with a diameter of 2.5 micrometres or less): these particles are so small they can get deep into the lungs and into the bloodstream. There is sufficient evidence that exposure to PM2.5 over long periods (years) can cause adverse health effects. Note that PM10 includes PM2.5. Prof. Khadiga Abou-Taleb  Particulate matter Sources can be divided into two types Coarse particles Fine particles formed when fuel is formed from sources burned in like road dust, sea automobiles and spray, and construction. power plants. Prof. Khadiga Abou-Taleb  Nitrogen and Sulfur Oxides Nitrogen Oxides – Gases produced by the chemical interactions between atmospheric nitrogen and oxygen at high temperature – Problems can give people coughs and can make them feel short of breath (difficulty breathing). Nitrogen dioxide reacts in the atmosphere to form acid rain, which can: - harm plants and animals Prof. Khadiga Abou-Taleb Sources: Nitrogen dioxide mostly comes from power plants and cars. Nitrogen dioxide is formed in two ways-when: - nitrogen in the fuel is burned - nitrogen in the air reacts with oxygen at very high temperatures. Nitrogen dioxide can also react in the atmosphere to form ozone, acid rain, and particles. Prof. Khadiga Abou-Taleb  Sulfur Oxides Gases produced by the chemical interactions between sulfur and oxygen. Sources:  Sulfur dioxide mostly comes from the burning of coal or oil in power plants.  It also comes from factories that make chemicals, paper, or fuel.  Like nitrogen dioxide, sulfur dioxide reacts in the atmosphere to form acid rain and particles. Effects: Sulfur dioxide exposure can affect people who have asthma or emphysema (swelling lungs) by making it more difficult for them to breathe. It can also irritate people's eyes, noses, and throats. Sulfur dioxide can harm trees and crops, damage buildings, and make it harder for people toProf. see long Khadiga distances. Abou-Taleb  Carbon Oxides and Carbon Oxides Hydrocarbons – Gases carbon monoxide (CO) and carbon dioxide (CO2) – Greenhouse gases Effects: -Carbon monoxide makes it hard for body parts to get the oxygen they need to run correctly. -Exposure to carbon monoxide makes people feel dizzy and tired and gives them headaches. In high concentrations it is fatal. Elderly people with heart disease are hospitalized more often when they are exposed to higher amounts of carbon monoxide. Hydrocarbons – Diverse group of organic compounds that contain only hydrogen and carbon (ex: CH4- methane) – Some are related to photochemical smog and greenhouse gases Prof. Khadiga Abou-Taleb  Ozone (O3) A gas that can be found in two places.  Bad ozone (Tropospheric ozone ) is a harmful pollutant, it is found in the troposphere, the layer nearest the ground, which forms when sunlight alters various chemicals emitted by humans.  "Good" ozone forms in the stratosphere, the next higher layer where some jet planes fly. the protective layer of ozone in the upper atmosphere (stratosphere), which screens out harmful ultraviolet rays. Source: Ozone is not created directly but is formed when nitrogen oxides and volatile organic compounds mix in sunlight. That is why ozone is mostly found in the summer. Nitrogen oxides come from burning gasoline, coal, or other fossil fuels. There are many types of volatile organic compounds, and they come from sources ranging from factoriesProf. to Khadiga trees. Abou-Taleb  Effects: Ozone near the ground can cause a number of health problems.  Ozone can lead to more frequent asthma attacks in people who have asthma and can cause sore throats, coughs, and breathing difficulty. It may even lead to premature death (irritate respiratory system and asthma; reduces lung function by inflaming and damaging lining of lungs).  Ozone can also hurt plants and crops.  at upper level, ozone shields Earth from sun’s harmful UV rays.  at ground level, ozone is harmful pollutants. formed from car, power, and chemical plant exhaust. Prof. Khadiga Abou-Taleb Lead A blue-gray metal that is very toxic and is found in a number of forms and locations. Sources: Outside: lead comes from cars in areas where unleaded gasoline is not used. Lead can also come from power plants and other industrial sources. Inside: lead paint is an important source of lead, especially in houses where paint is peeling. Lead in old pipes can also be a source of lead in drinking water. Effects: High amounts of lead can be dangerous for small children and can lead to lower IQs and kidney problems. For adults, exposure to lead can increase the chance of having heart attacks or strokes. Prof. Khadiga Abou-Taleb Air ​toxics Air toxics are another group of air pollutants that are typically present in low concentrations in the air but have toxic characteristics that may result in health effects from exposure even at low levels. Sources of air toxics included motor vehicle exhaust and some commercial and industrial processes. In 2004, the National Environment Protection Council made the National Environment Protection (Air Toxics) Measure which addresses the five priority air toxics: benzene, formaldehyde, toluene, xylenes and benzo (a) pyrene (as a marker for polycyclic aromatic hydrocarbons). Prof. Khadiga Abou-Taleb Biological pollutants 'Biological pollutants' are another class of pollutants. They arise from sources such as microbiological contamination, eg moulds, the skin of animals and humans and the remains and dropping of pests such as cockroaches. Biological pollutants can be airborne and can have a significant impact on indoor air quality. Effects of Air Pollution  Low level exposure: - Irritates eyes. - Causes inflammation of respiratory tract.  Can develop into chronic respiratory diseases. Prof. Khadiga Abou-Taleb  Effects of Air Pollution Low level exposure – Irritates eyes – Causes inflammation of respiratory tract Can develop into chronic respiratory diseases Prof. Khadiga Abou-Taleb Definition: A suspension of airborne particles that contain living organisms or were released from living organisms. Or Microorganisms or particles, gases, vapors, or fragments of biological origin (i.e., alive or released from a living organism) that are in the air. Prof. Khadiga Abou-Taleb  These particles are very small and range in size from less than one micrometer to one hundred micrometers.  Bioaerosols react to air currents and move quickly or slowly depending on the environment.  Bioaerosols are impacted by gravity but due to their size air density and air currents play a large role in their movement. Prof. Khadiga Abou-Taleb  The intact cellular component has been given the name, primary biological aerosol (PBA), which consists of virus particles, bacteria, fungal spores and plant pollen. PBA can range in size from 10 nanometers (small virus particles) to 100 micrometers (pollen grains). Prof. Khadiga Abou-Taleb Factors Influencing Airborne Infection Aerosol Factors Particlesize; 25 ppmv).  Compost biofilters (as naturally bioactive media) are capable of treating low concentration contaminants (< 25 ppmv) and are not ideally suited for treating air contaminated with high concentration organics. The reason for making this distinction is that naturally bioactive media exhibit :  low biodegradation rates,  limited supply of nitrogen and phosphorus,  limited capacity to neutralize acidic products of degradation. Prof. Khadiga Abou-Taleb  Prof. Khadiga Abou-Taleb Fig. (1): Diffusion Mechanisms operating in a Biofilters work by absorbing noxious gases into a biofilm where microorganisms break down the gases into carbon dioxide, water and salts and use the energy and nutrients to grow and reproduce. Well-designed and managed biofilters can reduce odours and hydrogen sulphide (H 2S) by as much as 95 % and ammonia (NH3) by 80 %. Prof. Khadiga Abou-Taleb A combination of a biofilter and a bioscrubber. The bacteria responsible for decomposition are immobilized on a carrier or filter material. The filter material consists of synthetic media.  Other types of support media used in biofilters are synthetic media, such as ceramic, plastic, metallic material, with active bacteria immobilized on the surface in the form of biofilms. These synthetic media biofilters, known as biotrickling filters  Synthetic support media are used in trickling filters for wastewater treatment, gas absorption, catalytic reactors. Prof. Khadiga Abou-Taleb  Synthetic support media can be in the form of high surface area pellets, with either a porous or non- porous surface.  In some cases, the support media may be coated with activated carbon, to enhance adsorption of contaminant(s).  Can handle high contaminant concentrations ( > 25 ppmv) Prof. Khadiga Abou-Taleb Prof. Khadiga Abou-Taleb Prof. Khadiga Abou-Taleb  Glossary Environmental The branch of biotechnology that addresses environmental problems, biotechnology such as the removal of pollution, renewable energy generation, or biomass production, by exploiting biological processes. Air Pollution -Any visible or invisible particle or gas found in the air that is not part of the original, normal composition. -Chemicals added to the atmosphere by natural events or human activities in high enough concentrations to be harmful. Primary Air Pollutant A harmful substance that is released directly into the atmosphere. Secondary Air Pollutant A harmful substance formed in the atmosphere when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants. Aerosol A suspension of fine solid particles or liquid droplets in the air. Bioaerosols A suspension of airborne particles that contain living organisms or were released from living organisms. Biofiltration The biological transformation or treatment of contaminants present in the gas phase, usually air. Biotrickling filter A combination of a biofilter and a bioscrubber. The bacteria responsible for decomposition are immobilized on a carrier or filter material. The filter material consists of synthetic media. Prof. Khadiga Abou-Taleb Quizzes 1. Define the following terms a. Air pollution b. Bioaerosols c. Biofiltration d. Biotrickling filter Compare between the following: e. Primary Air Pollutant & Secondary Air Pollutant f. Natural pollutants & Unnatural pollutants g. Naturally biofilter media & Synthetic biofilter media h. Bioaerosols & Biotrickling filters Give a short account -Diffusion mechanisms operating in a compost biofilter. Prof. Khadiga Abou-Taleb