ecology portfolio midterm

7/28/2019 Ecology Portfolio Midterm

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Ecology


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1. What is the effect of overpopulation on the environment?

Every second, on average, five children are born somewhere on theearth. In that same second, two other people die. This difference between

births and deaths means a net gain of three or more humans per second in

the world population. If you multiply this out, you will find we are growing at

a rate of about 11,000 per hour, 265,000 per day, or almost 100 million

more people per year.

Many people worry that overpopulation will cause--- or perhaps

already is causing--- resource depletion and environmental degradation

that threaten the ecological life-support systems on which we all depend.

These fears often lead to demands for immediate, worldwide birth control

programs to reduce fertility rates and to eventually stabilize or even shrink

the total number of humans.

Others believe that human ingenuity, technology and enterprise can

extend the world carrying capacity and allow us to overcome any problems

we encounter. From this perspective, more people may be beneficial rather

than disastrous. A larger population means a larger work force, more

geniuses, and more ideas about what to do. Along with every new mouth

comes a pair of hands. Proponents of this worldview

many of whomhappen to be economistsargue that continued economic and

technological growth can both feed the worlds billions and enrich

everyone enough to end the population explosion voluntarily. Not so,

counter many ecologists. Growth is the problem; we must stop both

population and economic growth.

Yet another perspective on this subject matter derives from social

justice concerns. From this worldview, there are enough resources for

everyone. Current shortages are only signs of greed, waste, andoppression. The root cause of environmental degradation, in this view is

inequitable distribution of wealth and power rather than population size.

Fostering democracy, empowering women and minorities, and improving

the standard of living of the worlds poorest people are what really needed.

A narrow focus on population growth only fosters racism and an attitude


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that blames the poor for their problems while ignoring the deeper social

and economic forces at work.

For an area to be considered overpopulated; its population reaches

a point where it can't be maintained without rapidly depleting non-

renewable resources (or converting renewable resources into non-

renewable ones) and without degrading the capacity of the environment to

support the population. In short, if its current human occupants are clearly

degrading the long-term carrying capacity of an area, then that area is

overpopulated (Ehrlich 1990). Overpopulation is a generally undesirable

condition where an organisms numbers exceed the carrying capacity of its

habitat. The term often refers to the relationship between the human

population and its environment, the Earth, or smaller geographical areas

such as countries. Overpopulation can result from an increase in births, a

decline in mortality rates, an increase in immigration, or an unsustainable

biome and depletion of resources. It is possible for very sparsely populated

areas to be overpopulated if the area has a meager or non-existent

capability to sustain life (e.g. a desert).

2. Explain how the environment is affected by the following:

a. Filipino values

Family is easily the most important Filipino core value, and it is every

Filipinos goal to provide the best for his family. This is most easily

achieved with the security of a home. Having a healthy and stable homeenvironment is one way to keep a family close. Mirroring this most core of

Filipino values, Highlands Prime Inc. (HPI) and Belle Corporation (Belle

Corp.) offer homes and amenities at Tagaytay Highlands which encourage

family interaction and enjoyment in a cool and unpolluted atmosphere.

This is just one of the examples on how the Filipino Values affect our

environment. Subdivisions became highly prioritized because we want to

preserve the idea ofstrong family ties.

b. Sociological and economic impact

Money and politics are the languages of most policy planners and

decision makers. They ask, How much will it cost? and What are the

benefits? Economists try to answer those questions. Basically, economics

deals with resource allocation or trade-offs, either on the micro scale of

buying and selling by individual persons and businesses, or on the macro


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scale of national policy and world economic systems. It is a description of

how valuable goods and services are to us we make decisions about how to

use time, energy, creativity or physical resources. If resources were

unlimited, there would be no need to choose between alternatives and no

need for a system of economics.Some economists argue that technological development and

substitution of one resource for another can indefinitely expand the carrying

capacity of the environment for human populations. Many ecologists warn,

however, that we are approaching or may already have exceeded the

capacity of our environment to supply essential resources, absorb wastes

and maintain the web of life on which we ultimately depend. Reconciling

these contrasting worldviews and finding optimum levels of population and

resource use is one of the most important issues in environment science.

Interestingly, ecology and economy are derived from the same rootwords and concerns. Oikos (ecos) is the old Greek word for household.

Economics is the nomos or counting of the household goods and services.

Ecology is the logos or logic of how the household works. In both disciplines,

household is extended to include the whole world.

c. Technological impact

For the past two centuries, a central tenet of Western culture has

been an again almost religious faith in progress: an inevitable march of

human betterment. Originally formulated during eighteenth century

enthusiasm over the American and French Revolutions, this theoryseemed to be proven by the increase in material wealth and standard of

living provided by the Industrial Revolution. But while technology and

development brought many benefits, they had a darker side as well.

Pollution, rapid urbanization, inhumane working conditions for many, and

vast disparities in wealth and power between classes still cause social

environmental crises. Whether the root causes of these problems are in

technology or human nature, technology clearly allows us to make

mistakes faster and on a larger scale than even before.

A nineteenth-century English backlash against the excesses ofindustrialization led by Ned Ludd gave rise to the term Luddites for

opponents of rampant technology. The Luddites smashed power looms

and other machines that were threatening the craft guilds, cottage

industries, and village networks that sustained traditional rural

communities.


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In this century, even more dangerous technologies, such as nuclear

weapons, biological warfare, and the petrochemical industry, along with

the problems caused by earlier technologies, such as biodiversity losses,

global climate changes, and destruction of stratospheric ozone, have led

many intellectuals and young people to question whether progress iseither possible or desirable. Neo-Luddites now assert that all large-scale

human endeavors eventually fail that science and technology cause more

problems than they solve, and that our only hope is to abandon modern

life and go back to a low-tech pastoral or hunting-and-gathering society.

Some neo-Luddites resort to terrorist bombings and sabotage to try

to bring down mainstream culture. Others flee to end-of-the-road refuges

where they attempt to recreate a simpler, agrarian life. Rural life can be

more resource intensive than urban living, however, especially if you

demand all the modern conveniences. We probably couldnt all live off

the land in remote places without very destructive environmental effects.

d. Political impact

3. What are the current environmental laws in our country?

ENVIRONMENTAL LAWS OF THE PHILIPPINES

ENVIRONMENTAL LAWS AND POLICIES

Bio 425/426/427 (Environmental Issues and Policies)

P.D. 984 Pollution Control Law

P.D. 1151 Philippine Environmental Policy


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- defines the general policies on the pursuit of a better quality of life for the present

and future generations and mandates the undertaking the environmental

impact assessments for all projects, which may significantly affect the

environment.

P.D. 1152 Philippine Environmental Policy

- defines the policy objectives and the strategies for the various aspects of

environmental management, such as air and water quality management,

natural source development, land management, and waste management. It

launches a comprehensive national program of environmental protection

and management, with reference to policies and standards of noise, air

quality, water quality, classification of water and waste management.

P.D. 1586 defines the framework for the implementation of the environmental

impact assessment as the mechanism to reconcile the impacts ofdevelopment projects on society and the physical environment.

P.D. 389 (P.D. 705) The Forestry Reform Code

- codifies, updates and raises forestry laws in the country. It emphasizes the

sustainable utilization of forest resources.

P.D. 330 & P.D. 953 laws on penalizing illegal cutting of trees

P.D. 953 & 1153 laws on tree planting

P.D. 331- laws requiring all public forests be developed on a sustained yield basis.

P.D. 704 preservation of optimum productivity of fishery resources through

conservation and protection.

P.D. 1015 banning the operation of commercial fishing within a distance of 7

kilometers from the shoreline.

P.D. 1058 increasing the penalties for illegal forms of fishing.

P.D. 1219 providing for the protection of coral ecosystems.

P.D. 1067 Water Code of the Philippines


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- adopts adequate measures to conserve and regulate the use of water in

commercial, industrial and residential areas. It also provides other policy

guidelines in water quality and management of water resources.

P.D. 463 amended the Mining Act of 1936, requires all mining leaseholders to

comply with Pollution Control Laws and regulations and provide forpenalties for noncompliance.

P.D. 1198 reinforces this provision for restoration of mined-out areas to this

original condition to the extent possible.

P.D. 1251 imposes fines on tailings and mine wastes and the fund generated is

used to pay for the damages to land, agricultural crops, forests products,

aquatic resources and infrastructures caused by pollution for mining

operations.

P.D. 984 The Pollution Control Law

P.D. 1181 (supplements the provision of P.D. 984) providing for the abatement,

control and prevention of vehicular pollution & establishing the maximum

allowance emissions of specific air pollutants from all types of vehicle.

P.D. 600 ( amended by P.D. 979) Water Pollution Control

- prohibits the discharge of oil, noxious liquid substances, and other harmful

substances into the countrys inland and territorial waters.

P.D. 825 prohibits the improper disposal of garbage

P.D. 856 Sanitation Code

- places the responsibility in the local government units for he solid waste

management in his area of production.

P.D. 1144 Control of Pesticides

R.A. 8749 Philippine Clean Air Act of 1999

- provides for a comprehensive air pollution control policy

R.A 3720 Food Additives

R.A. 6425 Drugs


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R.A 280 Cosmetics

R.A. 7160 Local Government Code of 1991

-provides that local government should share with the national government the

responsibility in the management and maintenance of ecological balancewithin their territorial jurisdiction subject to national policies and other

pertinent provisions of the code.

R.A. 6969 Toxic Substances and Hazardous and Nuclear Wastes Control Act

- authorizes the DENR to establish a program to regulate, restrict or prohibit the

importation, manufacture, processing, sale, destruction, use and disposal of

chemical substances, and mixture that present unreasonable risk and/or

injury to health or the environment.

R.A. 8550 The Fisheries Code of the Philippines

- defines the policies of the state in the protection, conservation and effective

management of fisheries stock as well as identifying allowable fishing

methods in Philippine coastal waters.

R.A. 9003 The Solid Waste Management Act of 2001- an act providing for an

ecological solid waste management program, creating the

necessary institutional mechanisms and incentives, declaring

certain acts prohibited and providing penalties, appropriatingfunds therefor, and for other purposes.

R.A. 9275- also known as the Philippine Clean Water Act of 2004 an act

providing a comprehensive water quality management and for

other purposes.

R.A. 9729 also known as the Climate Change Act of 2009. - an act mainstreaming

climate change into government policy formulations, establishing the framework

strategy and program on climate change, creating for this purpose the climatechange commission, and for other purposes.

4. What are environmental programs are you involved in?


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So far, I am not a member of any formal environmental programs.

However, I still know how to neutralize my wrong doings that may affect our

environment. Like for instance, I am implementing the proper waste

segregation in our home. It is simple yet I know that I could help even in a

very humble way because change should start in every house in the firstplace. I am not saying that our house will be totally free from plastic, but I can

assure myself on how to responsibly use it. After all, we could never put the

blame only with these. Instead, it should be the people who have all the

capabilities to think wisely and with sense of responsibility.

5. What is biological amplification or magnification? Give examples.

Biomagnification occurs when the toxic burden of a large number of

organisms at a lower trophic level is accumulated and concentrated by a

predator in a higher trophic level. Phytoplankton and bacteria in aquatic

ecosystems, for instance, take up heavy metals or toxic organic moleculesfrom water or sediments. Their predators---zooplankton and small fish---

collect and retain the toxins from many prey organisms, building up higher

concentrations of toxins. The top carnivores in the food chain---game fish,

fish-eating birds, and humans---can accumulate such high toxin levels that

they suffer adverse health effects.

Increase in concentration of certain stable chemicals (for example,

heavy metals or fat-soluble pesticides) in successively higher trophic levels of

a food chain or web.

6. Give examples of water pollutants.Although the types, sources, and effects of water pollutants are often

interrelated, it is convenient to divide them into major categories for

discussion. Lets look more closely some of the important sources and effects

of each type of pollutant.

Major Categories of Water PollutantsCategory Examples Sources

Causes health problems

Infectious agents Bacteria, viruses, parasites Human excreta Organic chemicals Pesticides, plastics, detergents, oil Industrial and farm

and gasoline use

Inorganic chemicals Acids, caustics, salts, metals Industrial effluents


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Household cleansers,

surface runoff

Radioactive materials Uranium, thorium, cesium, iodine Mining and

Radon processing of ores,power plants, weapons

production, naturalsources

Cause ecosystem disruption

Sediment soil, silt Land erosion Plant nutrients nitrates, phosphates agricultural and urban

fertilizers, sewage

manure

Oxygen demanding wastes animal manure and plant Sewage, agriculturalresidues runoff, paper mills,

food processing

Thermal Heat Power plants, industrial

cooling

7. What are the effects of water pollution on the human body? On the

environment?

The most serious water pollutants in terms of human health worldwide are

pathogenic organisms. Among the most important waterborne diseases are

typhoid, cholera, bacterial and amoebic dysentery, enteritis, polio, infectious

hepatitis and schistosomiasis, malaria, yellow fever and filariasis aretransmitted by insects that have aquatic larvae. Altogether, at least 25 million

deaths each year are blamed on these water-related diseases.

We have traditionally taken advantage of the capacity of ecosystems to

destroy these organisms, but as population density has grown, these systems

have become overloaded and ineffective. Effective sewage treatment systems

are needed that purify waste water before it is released to the environment.

In industrialized nations, toxic chemical wastes have become an increasing

problem. Agricultural and industrial chemicals have been released or spilled

into surface waters and are seeping into ground water supplies. The extent of

this problem is probably not yet fully appreciated.

Ultimately, all water ends up in the ocean. The ocean is so large that it

would seem impossible for human activities to have a significant impact on it,

but pollution levels in the ocean are increasing. Major causes of ocean

pollution are oil spills from tanker bilge pumping or accidents and oil well


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blowouts. Surface runoff and sewage outfalls discharge fertilizers, pesticides,

organic nutrients and toxic chemicals that have a variety of deleterious effects

on marine ecosystems. We usually think of eutrophication (increased

productivity due to nutrient addition) as a process of inland waterways, but

this can occur in oceans as well.

8. What measures should be taken to help prevent water pollution?

Appropriate land-use practices and careful disposal of industrial, domestic,

and agricultural wastes are essential for control of water pollution. Natural

processes and living organisms have a high capacity to remove or destroy

water pollutants, but these systems become overloaded and ineffective when

pollution levels are too high. Municipal sewage treatment is effective in

removing organic material from wastewater, but the sewage sludge is often

contaminated with metals and other toxic industrial materials. Reducing thesources of these materials is often the best solution to our pollution problems.

9. What are the sources of land pollution?

We produce enormous volumes of solid waste in industrialized societies,

and there is an increasing problem of how to dispose of those wastes in an

environmentally safe manner. In this chapter, we have looked at the character

of our solid and hazardous wastes. We have surveyed the ways we dispose

of our wastes and the environmental problems associated with waste

disposal.

Solid wastes are domestic, commercial, industrial, agricultural, and miningwastes that are primarily nontoxic. About 80 percent of our domestic and

industrial wastes are deposited in landills; most of the rest is incinerated or

recycled. Landfills are often messy and leaky, but they can be improved with

impermeable clay or plastic linings, drainage and careful siting. Incineration

can destroy organic compounds, but whether incinerators can or will be

operated satisfactorily is a matter of a debate. Recycling is growing

nationwide, encouraged by the economic and environmental benefits it brings.

City leaders tend to doubt the viability of recycling programs have been

sustained in other countries and in some American cities.10. What are the effects of land pollution on the human body? On the

environment?

Hazardous and toxic wastes, when released into the environment, cause

such health problems as birth defects, neurological disorders, reduced

resistance to infection, and cancer. Environmental losses include


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contamination of water supplies, poisoning of the soil, and destruction of

habitat. The major categories of hazardous wastes are ignitable, corrosive,

reactive, explosive, and toxic. Some materials that cause the most concern

are heavy metals, solvents, and synthetic organic chemicals such as

halogenated hydrocarbons, organophosphates and phenoxy herbicides.11. How can land pollution be controlled?

Disposal practices for solid and hazardous wastes have often been

unsatisfactory. Thousands of abandoned, often unknown waste disposal sites

are leaking toxic materials into the environment. Some alternative techniques

for treating or disposing of hazardous wastes include not making the material

in the first place, incineration, secure landfill, and physical, chemical, or

biological treatment to detoxify or immobilize wastes. People are often

unwilling to have transfer facilities, storage sites, disposal operations, or

transportation of hazardous or toxic materials in or through their cities.Questions of safety and liability remain unanswered in solid and hazardous

waste disposal.

12. Garbage disposal and collection in urban areas is a big problem. If you

were the City Mayor, how would you solve this problem?

If I were the city mayor, I would implement a fiercer PROPER WASTE

MANAGEMENT DISPOSAL ACT. An act in which every house must conduct

their own segregation of biodegradable and non-biodegradable materials

otherwise their garbage will not be collected. The local government should

provide at least 2 garbage bin for every family and each labelled withBIO/NABUBULOK and NON-BIO/DI NABUBULOK. In this way, garbage

collectors will be commanded that they will collect only those bins owned by

the municipality. I will also implement a two-day in a week collection of

garbage so that it could be easily handled in a very systematic way. In addition

to that, landfills will be manifested with a great maintenance and a highly

controlled human plus a technologically balanced labor of work.

13. What is noise?

We have known for a long time that prolonged exposure to noises, such as

loud music or the roar of machinery can result in hearing loss. Evidence nowsuggests that noise-related stress also causes a wide range of psychological

and physiological problems ranging from irritability to heart disease.

What is noise? There are many definitions, some technical and some

philosophical. What is music to your ears might be noise to someone else.

Simply defined, noise pollution is any unwanted sound or any sound that


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interferes with hearing, causes stress, or disrupts our lives. Sound is measured

either in dynes, watts or decibels.

City noises come from many sources. Traffic is generally the most

omnipresent noise. Cars, trucks, and buses create a roar that permeates

nearly everywhere in the city. Near airports, jets thunder overhead, stoppingconversation, rattling dishes, sometimes even cracking walls. Jackhammers

rattle in the streets; sirens pierce the air; motorcycles, lawnmowers,

snowblowers and chain saws create an infernal din; and music from radios,

TVs and loudspeakers fills the air everywhere.

14. What are the effects of noise?

Prolonged exposure to sounds above about 90 decibels can permanently

damage the sensitive mechanism of the inner ear. Extremely loud sounds----

above 130 db, the level of a loud rock band or music heard through earphones

at a high setting---actually can destroy sensory nerve endings, causingaberrant nerve signals that the brain interprets as a high-pitched whine or

whistle. You may have experienced ringing ears after exposure to very loud

noises. Coffee, aspirin, certain antibiotics, and fever also can cause ringing

sensations, but they usually are temporary.

A persistent ringing is called tinnitus. For most people, the ringing is

noticeable only in a very quiet environment, and we rarely are in a place that is

quiet enough to hear it. About thirty-five out of one thousand people have

tinnitus severely enough to interfere with their lives. Sometimes, the ringing

becomes so loud that it is endurable, like shrieking brakes on a subway train.Unfortunately, there is not yet a treatment for this distressing order.

15. How can noise be controlled?

One of the first charges to the EPA when it was founded in 1970 was to

study noise pollution and to recommend ways to reduce the noise in our

environment. Standards have since been promulgated for noise reduction in

automobiles, trucks, buses, motorcycles, mopeds, refrigeration units, power

lawnmowers, construction equipment, and airplanes. The EPA is considering

ordering the warnings be placed on power tools, radios, chain saws, and other

household equipment. The Occupational Safety and Health Agency also hasset standards for noise in the workplaces that have considerably reduced

noise-related hearing losses.

Noise is still all around us. In many cases, the most dangerous noise is

that to which we voluntarily subject ourselves. Perhaps if people understood


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the dangers of noise and the permanence of hearing loss, we would have a

quieter environment.

16. What are the types of ionizing radiation? Describe each.

Radiation is a very general term, used to describe any

process that transmits energy through space or a material away from a

source. Light, sound, and radio waves are all examples of radiation. Whenmost people think of radiation, however, they are thinking of ionizing radiation-

-radiation that can disrupt the atoms and molecules within the body. While

scientists think of these emissions in highly mathematical terms, they can be

visualized either as subatomic particles or as rays. Radiation's effects on

humans can best be understood by first examining the effect of radiation on

atoms, the basic building blocks of matter.

Atoms consist of comparatively large particles (protons and neutrons) sitting

in a central nucleus, orbited by smaller particles (electrons): a miniature solarsystem. Normally, the number of protons in the center of the atom equals the

number of electrons in orbit. An ion is any atom or molecule that does not

have the normal number of electrons. Ionizing radiation is any form of

radiation that has enough energy to knock electrons out of atoms or

molecules, creating ions.

There are many types of ionizing radiation, but the most familiar are alpha,

beta, and gamma/x-ray radiation. Neutrons, when expelled from atomic nuclei

and traveling as a form of radiation, can also be a significant health concern.Alpha particles are clusters of two neutrons and two protons each. They are

identical to the nuclei of atoms of helium, the second lightest and second most

common element in the universe, after hydrogen. Compared with other forms

of radiation, though, these are very heavy particles--about 7,300 times the

mass of an electron. As they travel along, these large and heavy particles


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frequently interact with the electrons of atoms, rapidly losing their energy.

They cannot even penetrate a piece of paper or the layer of dead cells at the

surface of our skin. But if released within the body from a radioactive atom

inside or near a cell, alpha particles can do great damage as they ionize

atoms, disrupting living cells. Radium and plutonium are two examples ofalpha emitters.

Beta particles are electrons traveling at very high energies. If alpha particles

can be thought of as large and slow bowling balls, beta particles can be

visualized as golf balls on the driving range. They travel farther than alpha

particles and, depending on their energy, may do as much damage. For

example, beta particles in fallout can cause severe burns to the skin, known

as beta burns. Radiosotopes that emit beta particles are present in fission

products produced in nuclear reactors and nuclear explosions. Some beta-emitting radioisotopes, such as iodine 131, are administered internally to

patients to diagnose and treat disease.

Gamma and x-ray radiation consists of packets of energy known as photons.

Photons have no mass or charge, and they travel in straight lines. The visible

light seen by our eyes is also made up of photons, but at lower energies. The

energy of a gamma ray is typically greater than 100 kiloelectron volts (keV--"k"

is the abbreviation for kilo, a prefix that multiplies a basic unit by 1,000) per

photon, more than 200,000 times the energy of visible light (0.5 eV). If alphaparticles are visualized as bowling balls and beta particles as golf balls,

photons of gamma and x-radiation are like weightless bullets moving at the

speed of light. Photons are classified according to their origin. Gamma rays

originate from events within an atomic nucleus; their energy and rate of

production depend on the radioactive decay process of the radionuclide that is

their source. X rays are photons that usually originate from energy transitions

of the electrons of an atom. These can be artificially generated by bombarding

appropriate atoms with high-energy electrons, as in the classic x-ray tube.

Because x rays are produced artificially by a stream of electrons, their rate ofoutput and energy can be controlled by adjusting the energy and amount of

the electrons themselves. Both x rays and gamma rays can penetrate deeply

into the human body. How deeply they penetrate depends on their energy;

higher energy results in deeper penetration into the body. A 1 MeV ("M" is the

abbreviation for mega, a prefix that multiplies a basic unit by 1,000,000)


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gamma ray, with an energy 2,000,000 times that of visible light, can pass

completely through the body, creating tens of thousands of ions as it does.

A final form of radiation of concern is neutron radiation. Neutrons, along with

protons, are one of the components of the atomic nucleus. Like protons, theyhave a large mass; unlike protons, they have no electric charge, allowing

them to slip more easily between atoms. Like a Stealth fighter, high-energy

neutrons can travel farther into the body, past the protective outer layer of the

skin, before delivering their energy and causing ionization.

Several other types of high-energy particles are also ionizing radiation.

Cosmic radiation that penetrates the Earth's atmosphere from space consists

mainly of protons, alpha particles, and heavier atomic nuclei. Positrons,

mesons, pions, and other exotic particles can also be ionizing radiation.17. What are the sources of radiation? Give examples.

We live in a radioactive world. There are many natural sources of radiation

which have been present since the earth was formed. In the last century, we

have added somewhat to this natural background radiation with some artificial

sources. It may surprise you to know that for an average person, the naturally

occurring sources contribute about four to five times as much to your

exposure as the human-made sources.

NATURAL RADIATION

The three major sources of naturally occurring radiation are:

cosmic radiation

sources in the earth's crust, also referred to as terrestrial radiation

sources in the human body, also referred to as internal sources.

Cosmic radiation comes from the sun and outer space and consists of

positively charged particles, as well as gamma radiation. At sea level, theaverage cosmic radiation dose is about 26 mrem per year. At higher

elevations the amount of atmosphere shielding cosmic rays decreases and

thus the dose increases. The average dose in the United States is

approximately 28 mrem/year.


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There are natural sources of radiation in the ground, rocks, building materials

and drinking water supplies. This is called terrestrial radiation. Some of the

contributors to terrestrial sources are natural radium, uranium and thorium.

Radon gas is a current health concern. This gas is from the decay of natural

uranium in soil. Radon, which emits alpha radiation, rises from the soil underhouses and can build up in homes, particularly well-insulated homes. In the

USA, the average effective whole body dose from radon is about 200 mrem

per year while the lungs receive approximately 2000 mrem per year.

Our bodies also contain natural radionuclides. Potassium 40 is one example.

The total average dose is approximately 40 mrem/year.

HUMAN SOURCES

The difference between man-made sources of radiation and naturally

occurring sources is the place from which the radiation originates. The

following information briefly describes some examples of human-made

radiation sources.

Medical radiation sources

X rays are identical to gamma rays; however, they are produced by a different

mechanism. X rays are an ionizing radiation hazard. A typical radiation dosefrom a chest x ray is about 10 mrem. The total average dose from medical x

rays is 40 mrem in a year. In addition to x rays, radioactive isotopes are used

in medicine for diagnosis and therapy. The total average dose is 14 mrem in a

year.

Consumer products

Examples include TV's, older luminous dial watches, some smoke detectors,

and lantern mantles. This dose is relatively small as compared to other

naturally occurring sources of radiation and averages 10 mrem in a year.

Atmospheric testing of nuclear weapons

Another man-made source of radiation includes residual fallout from

atmospheric nuclear weapons testing in the 1950's and early 1960's.


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Atmospheric testing is now banned by most nations. The average dose from

residual fallout is about 2 mrem in a year.

Industrial uses

Industrial uses of radiation include x-ray machines and radioactive sources(radiography) used to test pipe welds, bore-holes, etc. Most people receive

little if any dose from these sources.

As a whole, these sources of natural and human-made radiation are referred

to as background.

The average annual radiation dose to a member of the general population

from ALL background sources is about 360 millirem.

18. What are the possible effects of radiation on the human body?

Radiation Effects on Humans


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Certain body parts are more specifically affected by exposure to different

types of radiation sources. Several factors are involved in determining the

potential health effects of exposure to radiation. These include:

The size of the dose (amount of energy deposited in the body)The ability of the radiation to harm human tissue

Which organs are affected

The most important factor is the amount of the dose - the amount of energy

actually deposited in your body. The more energy absorbed by cells, the

greater the biological damage. Health physicists refer to the amount of energy

absorbed by the body as the radiation dose. The absorbed dose, the amount

of energy absorbed per gram of body tissue, is usually measured in units

called rads. Another unit of radation is the rem, or roentgen equivalent in man.

To convert rads to rems, the number of rads is multiplied by a number thatreflects the potential for damage caused by a type of radiation. For beta,

gamma and X-ray radiation, this number is generally one. For some neutrons,

protons, or alpha particles, the number is twenty.

Hair

The losing of hair quickly and in clumps occurs with radiation exposure at 200

rems or higher.

Brain

Since brain cells do not reproduce, they won't be damaged directly unless the

exposure is 5,000 rems or greater. Like the heart, radiation kills nerve cells

and small blood vessels, and can cause seizures and immediate death.


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Thyroid

The certain body parts are more specifically affected by exposure to different

types of radiation sources. The thyroid gland is susceptible to radioactiveiodine. In sufficient amounts, radioactive iodine can destroy all or part of the

thyroid. By taking potassium iodide can reduce the effects of exposure.

Blood System

When a person is exposed to around 100 rems, the blood's lymphocyte cell

count will be reduced, leaving the victim more susceptible to infection. This is

often refered to as mild radiation sickness. Early symptoms of radiation

sickness mimic those of flu and may go unnoticed unless a blood count isdone.According to data from Hiroshima and Nagaski, show that symptoms

may persist for up to 10 years and may also have an increased long-term risk

for leukemia and lymphoma. For more information, visit Radiation Effects

Research Foundation.

Heart

Intense exposure to radioactive material at 1,000 to 5,000 rems would do

immediate damage to small blood vessels and probably cause heart failureand death directly.

Gastrointestinal Tract

Radiation damage to the intestinal tract lining will cause nausea, bloody

vomiting and diarrhea. This is occurs when the victim's exposure is 200 rems

or more. The radiation will begin to destroy the cells in the body that divide

rapidly. These including blood, GI tract, reproductive and hair cells, and harms

their DNA and RNA of surviving cells.

Reproductive Tract


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Because reproductive tract cells divide rapidly, these areas of the body can be

damaged at rem levels as low as 200. Long-term, some radiation sickness

victims will become sterile.

Dose-rem Effects5-20 Possible late effects; possible chromosomal damage.

20-100 Temporary reduction in white blood cells.

100-200 Mild radiation sickness within a few hours: vomiting, diarrhea,

fatigue; reduction in resistance to infection.

200-300 Serious radiation sickness effects as in 100-200 rem and

hemorrhage; exposure is a Lethal Dose to 10-35% of the population after 30

days (LD 10-35/30).

300-400 Serious radiation sickness; also marrow and intestine destruction;

LD 50-70/30.400-1000 Acute illness, early death; LD 60-95/30.

1000-5000 Acute illness, early death in days; LD 100/10.

19. How can the hazards of radiation be minimized?

You are probably familiar with a few uses of radiation, like x-rays and nuclear

power. But did you know there are lots of ways radiation is used in the

workplace? Radiation is used to sterilize health products, to treat cancer and

other diseases, to measure the moisture content of soil at construction sites,to locate leaks in pipelines and defects in welds, to make fluorescent bulbs

last longer, to make lightning rods work better--the list goes on and on.

Radiation is a tool that is used for great benefit to our society. But radiation

can be harmful if it isn't controlled. Do you know the hazards of radiation

exposure and how to protect against them? In this week's Safety Topic, we

discuss radiation safety. Know what radiation is, its hazards, and what you

should know if you work where radiation is used.

Many people think radiation is some type of chemical or gas. It isn't. Althoughsome chemicals or gases may be "radioactive"--they emit radiation--radiation

itself is simply energy. There are many types of radiation. Some types of

energy can be seen or felt, such as visible light and infrared radiation. Some

types cannot be detected without special equipment. The type of radiation we

will discuss is known as "ionizing" radiation. Ionizing radiation cannot be seen


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or felt. It must be detected with special equipment. Ionizing radiation, unlike

infrared, microwave, lasers, and most ultraviolet radiation, is energetic enough

to remove electrons from their orbit about the nucleus of an atom. Ionization

changes the atom. If the atom is part of a living cell, those changes could

cause a health effect.

You are probably familiar with x-ray radiation. X-rays pass through objects

and expose film. Dense areas absorb the x-rays so they appear lighter on film

than non-dense areas which allow the radiation to pass through. This is why

x-ray radiation is useful in many applications, from medicine to security to

radiography of welds and other critical structures. X-rays are ionizing

radiation. Gamma radiation is similar to x-ray radiation. The other types of

ionizing radiation are actually small, energetic particles known as alpha and

beta particles. Another type of particle radiation is the neutron. All these typesof radiation can cause change to the body's cells.

In order for radiation to affect the body, a person must be exposed to it.

Radiation exposure may occur from radiation sources located outside the

body, known as "external exposure," or it may occur from sources of radiation

located inside the body, known as "internal exposure." Internal exposure

results from the inhalation, ingestion, or other uptake of radioactive material

by the body. Radioactive material is material which emits radiation, such as

radioactive uranium, radium, cobalt, and thorium.

Health effects of radiation exposure have been studied for years. It is very

clear that at high levels of exposure, serious health effects occur. These

health effects are destruction of bone marrow, incapacitation of the digestive

and nervous systems, birth defects in children born to exposed mothers, and

increased incidence of cancer in exposed populations. A localized exposure

could result in the loss of a hand or foot. These effects are clearly evident at

high exposures such as those produced by an atomic bomb detonation or

serious accident involving radioactive materials. However, these exposuresare much, much larger than those encountered in the workplace. In fact, the

health effects of low exposures, such as those received in the workplace,

aren't as obvious as those from high exposures. They're really not obvious at

all.


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Radiation exposure at the occupational level does not cause obvious bone

marrow damage or digestive or nervous system effects. It has not been

shown to cause cancer or birth defects. Localized low exposures to the hands

and feet, and arms and legs do not cause obvious harm. To be on the safe

side, information from persons exposed to high levels of radiation has beenused to predict possible health effects to persons exposed to low levels. Since

high exposures cause a significant increase in the incidence of cancer, low-

level exposure may cause a small increase in the risk of cancer. To minimize

this risk, occupational radiation exposures are limited to very low levels.

Companies and other institutions that use radiation are regulated by the

Nuclear Regulatory Commission, the Department of Energy, or their state

radiological control agency. Persons who work with radiation must be trained

in radiation safety, radiation exposure risks and radiation safety practices.They are taught to minimize their radiation exposure by using these

techniques:

1. Time--Decrease the amount of time spent near a radiation source.

2. Distance--Increase distance between yourself and a radiation source.

3. Shielding--Use appropriate shielding to reduce radiation exposure.

Depending on the type of radiation used, other specific safety rules apply. For

example, persons who work with radiography sources must wear an alarming

radiation measurement device to warn them when the radiation level exceeds

a certain level. They must also never, ever assume the radiation source is

shielded without checking it with a radiation detector--at a safe distance from

the source. Some of the highest accidental radiation exposures (well in

excess of regulatory limits) have occurred in the radiography industry. These

accidents have caused serious local injuries and have even been fatal.

Persons with a potential for internal exposure are also taught to use

respirators or other protective equipment to minimize their uptake of

radioactive material. Some other techniques for minimizing potential internal

exposure are:


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1. No eating, drinking, smoking, or cosmetic application in areas where

radioactive materials are used.

2. Check the work area frequently for "contamination"--radioactive material

which has spilled into the work area--and clean it up immediately.

3. Use gloves, respirators, and other protective equipment as required. Use it

consistently and don't take shortcuts.

4. Everyone who works with radiation should also know their institution's

radiation safety procedures, including what to do during an emergency.

Radiation need not be feared, and you don't even have to thoroughly

understand it to work with it safely. Radiation, like many potentially harmfulthings, is a very useful tool and can be safely controlled. If you work with

radiation, or if you work in an area where radiation is used, learn your

company's procedures for radiation safety, and apply the common-sense

safety practices discussed in this week's Safety Topic.

20. What are the pros and cons of eating natural foods and foods that

contain chemical additives?

Humans have probably always known of ways to protect themselves from

annoying creatures, but our war against pests entered a new phase with theinvention of synthetic organic chemicals such as DDT. These chemicals have

brought several important benefits, including increased crop production and

control of disease-causing organisms. Indiscriminate and profligate pesticide

use also has caused problems, such as killing non-target species. Often highly

persistent and mobile in the environment, many pesticides move through air,

water, and soil and bioaccumulate or bioconcentrate in food chains causing

serious ecological and human health problems

Regulating pesticide use is a controversial subject. Many people fear that

we are exposed to far too many dangerous chemicals. Industry claims that itcould not do business without these materials. The Delaney Clause, an

amendment to the Federal Food, Drug and Cosmetic Act, prohibits wilful

addition of any known carcinogen to foods, drugs or cosmetics. Although noble

in intention, this amendment has become difficult to enforce as we find that


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many commonly used materials are carcinogens. Should we weaken the law

and allow some carcinogens as long as the risk is negligible?

Many of the procedures and approaches suggested for agriculture and

industry also work at home to protect us from pests and toxic chemical alike.

By using a little common sense, we can have a healthier diet, lifestyle andenvironment.

21. Is analgesic a pain killer or a germ fighter?

An analgesic is any member of the group of drugs used to achieve

analgesia, relief from pain. The word analgesic derives from Greek -

("without")

Commonly known as painkillers, analgesic drugs act in various ways on

the peripheral and central nervous systems. They are distinct from

anesthetics, which reversibly eliminate sensation, and include paracetamol(known in the US as acetaminophen or simply APAP), the non-steroidal anti-

inflammatory drugs (NSAIDs) such as the salicylates, and opioid drugs such

as morphine and opium.

Therefore, analgesic is a pain killer not a germ fighter.

22. Many consumer products are almost identical in chemical

composition but are sold under different brand names and at varying

prices. Do you think these products should be identified by their chemical

(generic) names or their trade names? Why?

It is very logical to say that it should be identified by their chemical orgeneric names primarily because these chemicals are commonly used in

drugs, foods and cosmetics. It has to be identified that way in order for the

people to be aware and informed that the components of what theyre taking

are standardly safe and approved by the FDA. We often argue that medicines

that are sold cheaper are somewhat questionable in quality and competence

but the fact is, theyre being sold under a new brand name yet the same

chemical (generic) name. Therefore, their components are also the same. It is

very important to understand this because; this is a matter of Intake. Of

course we dont want to be stupid whenever taking drugs.23. Differentiate between an active and a passive smoker.

Active smoking is the inhaling of smoke by the smoker himself.As the name

suggests, active smoking means that the person is actively lighting up a

cigarette and smoking it. The negative health aspects associated with cigarette

smoke are obviously in line with this type smoking. But here, the process of


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smoking has a greater psychological impact due to the cigarette, which creates

an oral fixation. In addition, the staining of fingers and the oropharynx due to

nicotine is more with active smoking. The hot air and the heated particles can

scorch the epithelium causing more infections in the upper respiratory tract.

Passive smoking is the inhaling of smoke by the non-smokers in some

smoke-filled places. Passive smoking, also known as second hand smoking or

environmental tobacco smoke, is created through the exhaled particles of an

active smoker. This is also associated with similar conditions as mentioned

above but some are to a lesser aspect. There is no psychological dependence,

but there can be a chemical dependence created by it. There will be no

staining due to nicotine, and the scorching of the oropharynx is also absent.

24. What are the effects of alcohol on the human body?Drinking too much on a single occasion or over time can take a serious

toll on your health. Heres how alcohol can affect your body:

Brain:

Alcohol interferes with the brains communication pathways, and can affect

the way the brain looks and works. These disruptions can change mood and

behavior, and make it harder to think clearly and move with coordination.

Heart:Drinking a lot over a long time or too much on a single occasion can damage

the heart, causing problems including:

Cardiomyopathy Stretching and drooping of heart muscle

Arrhythmias Irregular heart beat

Stroke

High blood pressure

Research also shows that drinking moderate amounts of alcohol may protect

healthy adults from developing coronary heart disease.

Liver:

Heavy drinking takes a toll on the liver, and can lead to a variety of problems

and liver inflammations including:


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Steatosis, or fatty liver

Alcoholic hepatitis

Fibrosis

Cirrhosis

Pancreas:Alcohol causes the pancreas to produce toxic substances that can eventually

lead to pancreatitis, a dangerous inflammation and swelling of the blood

vessels in the pancreas that prevents proper digestion.

Cancer:

Drinking too much alcohol can increase your risk of developing certain

cancers, including cancers of the:

MouthEsophagus

Throat

Liver

Breast

Immune System:

Drinking too much can weaken your immune system, making your body a

much easier target for disease. Chronic drinkers are more liable to contract

diseases like pneumonia and tuberculosis than people who do not drink too

much. Drinking a lot on a single occasion slows your bodys ability to ward offinfections even up to 24 hours after getting drunk.

25. Describe some environmental episodes and their effects on the

environment.

Chernobyl: could it happen here?

In the early morning hours of April 26, 1986, residents of the Ukrainian

Village of Pripyat saw a spectacular and terrifying sight. A glowing fountain of

molten nuclear fuel and burning graphite was spewing into the dark sky

through a gaping hole in the roof of the Chernobyl Nuclear Power Plant only

a few kilometres away. Although officials assured them that there wasnothing to worry about in this rapid fuel relocation, the villagers knew that

something was terribly wrong. They were witnessing the worst possible

nuclear fuel and rupture of the containment facilities, releasing enormous

amounts of radioactivity into the environment.


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Development at what cost?

Thirty years ago, the island nation of Taiwan was among the worlds poorer

countries with an annual net income of about $400 per person. Rapid

industrialization has brought remarkable economic growth averaging nearly

10 percent per year over the past three decades. By 1996, Taiwan is theexpected to have a per capita income of more than $14,000 per year, making

it one of the 20 richest countries in the world. Many Taiwanese now have a

material lifestyle comparable to the average American or European. This

spectacular growth has not been without costs, however, Air Pollution in

Taipei, the capital city, exceeds health standards 55 days each year, and the

multitude of new automobiles, motorcycles and trucks causes horrendous

traffic jams nearly all the time. Cancer has become the leading cause of

death in Taiwan, perhaps because of the noxious fumes emitted by the

numerous petrochemical plants and plastic factories.26. What are the sources of air pollution?

Natural Sources of Air Pollution

It is difficult to give a simple, comprehensive definition of pollution. The

word comes from the Latinpollutes, which means made foul, unclean, or dirty.

Some authors limit the use of the term to damaging materials that are

released into the environment by human activities. There are, however, many

natural sources of air quality degradation. Volcanoes spew out ash, acid

mists, hydrogen sulfide and other toxic gases. Sea spray and decaying

vegetation are major sources of reactive sulphur compounds in the air. Forestfires create clouds of smoke that blanket whole continents. Trees and bushes

emit millions of tons of volatile organic compounds creating, for example, the

blue haze that gave the Blue Ridge Mountains their name. Pollen, spores,

viruses, bacteria and other small bits of organic material in the air cause wide

spread suffering from allergies and airborne infections. Storms in arid regions

raise dust clouds that transport millions of tons of soil and can be detected

half a world away. Bacterial metabolism of decaying vegetation in swamps

and of cellulose in the guts of termites and ruminant animals is responsible for

as much as two-birds of the methane (natural gas) in the air.In many cases, the chemical compositions of pollutants from natural and

human-related sources are identical, and their effects are inseparable.

Sometimes, however, materials in the atmosphere are considered innocuous

at naturally occurring levels, but when humans add to these levels,

overloading of natural cycles or disruption of essential processes can occur.


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While the natural sources of suspended particulate material in the air

outweigh human sources at least tenfold worldwide, in many cities more than

90 percent of the airborne particulate matter is anthropogenic (human-

caused)

Human-Caused Air PollutionAir pollution includes the chemicals sulphur dioxide and nitrogen oxides.

These gases are produced when fuel is burned in cars, power plants,

furnaces and factories. The gases become strong acids when combined with

moisture in the air. When the moisture condenses to form rain, the rain is

acidic too.

27. What is the greenhouse effect? Acid rain?

Greenhouse effect- The greenhouse effect refers to circumstances where

the short wavelengths of visible light from the sun pass through a transparent

medium and are absorbed, but the longer wavelengths of the infrared re-radiation from the heated objects are unable to pass through that medium.

The trapping of the long wavelength radiation leads to more heating and a

higher resultant temperature. Besides the heating of an automobile by

sunlight through the windshield and the namesake example of heating the

greenhouse by sunlight passing through sealed, transparent windows, the

greenhouse effect has been widely used to describe the trapping of excess

heat by the rising concentration of carbon dioxide in the atmosphere. The

carbon dioxide strongly absorbs infrared and does not allow as much of it to

escape into space.

Bright sunlight will effectively warm your car on a cold, clear day by

thegreenhouse effect. The longer infrared wavelengths radiated by sun-

warmed objects do not pass readily through the glass. The entrapment of this
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energy warms the interior of the vehicle. The trapping of the hot air so that it

cannot rise and lose the energy by convection also plays a major role.

Short wavelengths

ofvisible light are readilytransmitted through

the transparentwindshield.

(Otherwise you wouldn't

be able to see through it!)

Shorter wavelengths of ultraviolet light are largely blocked by glass since

they have greater quantum energies which have absorption mechanisms in

the glass. Even though you may be uncomfortably warm with bright sunlight

streaming through, you will not be sunburned.

Acid rain- normal rain or snow is slightly acidic. It has a ph (the measureof acidity) of about 5.6. Precipitation with a ph less than 5.6 is considered acid

rain. Acid rain can have a ph as low as 4.0 or even lower. Thats more than

15 times the acidity of normal rain.

Acid rain can be controlled in several ways. Adding lime to streams and

lakes temporarily lowers the acidity of the water. Cleaner burning fuels

produced less acid-causing air pollution. Burning less fuel and using fuels

more efficiently also helps. Putting emission-control devices on smokestacks,

chimneys and car exhausts also lowers the amount of acid-causing pollution

that gets into the air.28. What are the effects of air pollution on the human body? On the

environment?

Air pollution harms the lungs and eyes of animals and people. Air pollution

also damages plants, including farm crops. Plants along highways are often
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stunted because of exhaust fumes. Air pollution causes acid rain and even

damages buildings made of stone and steel.

29. What are some measures that you can do to help prevent air

pollution?

As you learn more about air pollution and what causes it, you will want tolearn more about air pollution control measures. There are many things we all

can do to help make our air a little cleaner. Individuals can do things like

carpooling, walking, and riding bikes to help with air pollution control. On a

larger scale, there are many different types of equipment available for

businesses and factories that cut down, or even prevent air pollution.

Some ways an individual can help control air pollution, is to use alternate

means of transportation to places like shopping, and work. However, if your

work is too far away to walk or bike, then you can do things like carpool with

co-workers to decrease the amount of pollution. If you want to help prevent airpollution indoors then you can start with having adequate ventilation in all

rooms, and if needed you can have exhaust systems installed. Another

terrible source of indoor air pollution is cigarette smoking.

It is best to avoid being exposed to any cigarette smoke whenever

possible. These are some of the ways you could practice good air pollution

control on an individual level. However, if you do a bit of research and get

creative, then you can find even more ways to clean up the air.

When it comes to air pollution control on a large scale, then it is the job of

businesses to get the proper equipment needed to control each type of pollution.

There are many different products that can be purchased to help prevent and

sometimes eliminate pollution of the air. These products include, bag house

filters, activated carbon absorbers, and gas absorption towers.

The baghouse filter can be used in many areas like, coal, power, steel,

chemical, and even mining industries. These types of filters can handle the

filtration of huge gas volumes and remove most particulate pollution from air

before it is released into the atmosphere. The carbon absorbers remove things

like organic acids, hydrogen sulfide, and aldeheydes. These filters can be usedin many different industries to aid in air pollution control.

The chemical absorption towers are designed to remove many chemicals

in different industries like, hydrogen sulfide, ammonia, sulfuric acid, nitrogen

oxides, sulfur dioxide, and many more. Many places where this equipment is

available can customize the equipment to the businesses specific needs and


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size, making it better at air pollution control. More and more industries are using

these wonderful tools to help them do their part to clean up the air we breathe.

ecology portfolio midterm

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