POLLUTION

CAUSES AND CONTROL

SAMEH ABDELGHANY

Abstract Pollution is a very critical issue that faces our environment. To control this pollution, we

need to understand the characteristics and behavior of different pollutants to provide effective strategies and legislation. Pollution impacts our environment in many ways that are evaluated and controlled. Ionization is one of the most harmful pollutions. It affects living organisms’ genetic characteristics, but with some interventions, we can

minimize its effect. As pollution has a great impact on our environment, manipulation of food is required to improve our nutritious food. All of these strategies and controls are

evaluated, and the data obtained from it can help to improve these policies.

DOI: 10.13140/RG.2.1.4931.1126

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Pollution

Introduction

Pollution is a very critical issue that faces our environment. To control this pollution, we need to

understand the characteristics and behavior of different pollutants to provide effective strategies and

legislation. Pollution impacts our environment in many ways that are evaluated and controlled. Ionization

is one of the most harmful contaminations. It affects living organisms’ genetic characteristics, but with

some interventions, we can minimize its effect. As pollution has a significant impact on our environment,

the manipulation of food is required to improve our nutritious food. All of these strategies and controls

are evaluated, and the data obtained from it can help to improve these policies.

Characteristics of common pollutants

Conventional pollutants have many characteristics, such as water solubility, density, toxicity, degradation,

chemical reactivity, bioaccumulation, and biomagnification. Some pollutants are soluble in water. It might

cause harm to any organism that drinks this water. Density; the harmful of the pollutant increases as the

density increases, while in low frequencies, the effect will be minimal or no effect. Toxicity differs from

pollutant to another. Some are very toxic and can cause death, while others are low toxic which may cause

harm after a long time. Some toxic pollutants are found in wastewater treatment plants that can be

discharged into water. Degradability as the pollutant will not be harmful after some time, but another

pollutant can resist the degradability and become dangerous. For example, POPs- Persist Organic

Pollutants. Chemical Reactivity depends on the compatibility of chemicals. Some chemicals are not

harmful if they existed with incompatible other chemicals, but in the presence of compatible chemicals,

both might be harmful. Bioaccumulation is the accumulation of pollutants in the organism. A pollutant

can gradually accumulate through the food chain. For example, mercury can accumulate in living tissues.

Biomagnification is a result of bioaccumulation. The tissue concentration of a pollutant in one trophic

level exceeds the tissue concentration at the next lower trophic level in the food chain (EPA, 2012). Algae

absorb mercury in seawater. When a fish feeds on algae, it can absorb mercury, which accumulates in

their tissues. The human who feeds on this fish can consume higher amounts of mercury.

There are some strategies that have been established to control the toxicity of pollutants. They are, for

example, TSCA, NEHAPS, and Ambient Air Quality Directive (2008/50/EC). Toxic Substances Control Act

(TSCA) 1976 in the US is one of the most effective laws in the U.S. It contains three essential parts. In part

1, it must for companies to notify the EPA 90 days before they import or manufacture chemical substances

not currently in commercial use. In part 2, the EPA examines chemicals that were in commercial use before

the law passed. Finally, the EPA has to control hazardous chemicals. NEHAPS (The National Emission for

Hazardous Air Pollutants Standard) is established for air toxic emission emitted from industrial activities

that require the use of Maximum Achievable Control Technology (MACT) for compliance. I think it is

beneficial to control mercury emissions in the U.S. Ambient Air Quality Directive (2008/50/EC) succeeded

in controlling outdoors air significant pollutants such as nitrogen oxides. The emission decreased by 44%

in 2011 below 1990 levels (EEA, 2015). It sets standards and plans to combat the discharge of pollution at

source and implement effective emission reduction measures.

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The pollutants are very harmful to the environment and living organisms. They have two types of impact;

direct effect- it can cause harm to the environment directly by contact, inhalation, ingestion or absorption,

or indirect effect- the pollutant can cause damage indirectly, for example, sulfur dioxide may cause harm

to organisms by acid precipitation. Other impacts can be determined by the time, as the pollutant may

cause immediate damage, for example, oil spills- acute effect, or chronic effect that pollutant has a long

term effect such as bioaccumulation of toxic compounds. Pollutants have many routes in the

environment. This can determine the behavior of the contaminant. It takes paths from its point of source

to the sink. These routes are called pathways. Pollutant has different routes in both water and air. It

depends on the physical state of it, whether it is solid, liquid or gas. Some pollutants may travel in the

atmosphere or water as long as hundreds or thousands kilometer. The pollutant may dilute during his trip

which affects the traveling distance.

Control of Pollution

Pollutants affect the atmosphere, water, and soil. Control strategies and legislation have been established

in order to control all types of pollution. Some of these strategies are; Air Pollution Controls, Clean Air Act

1990, Montreal Protocol, and the Kyoto Protocol. Air Pollution Controls is one of the most critical controls.

As acid precipitation can be considered one of air pollution, it can be controlled by using fuel sufficient

and alternative renewable sources. Another strategy is that reduce our energy demand; by providing

population growth management and stabilization. The US has established the Clean Air Act 1990 in order

to control acid deposition. I believe it is an effective intervention done by the US EPA as it succeeded in

reducing SO2 emissions by 50% by 2010 (EPA, 2014). In order to control ozone depletion,

Hydrochlorofluorocarbons (HCFCs) are used as a substitution of Chlorofluorocarbons (CFCs). Montreal

Protocol 1987 can be considered one of the most critical interventions to control ozone depletion. It

succeeded in reducing CFC's emission on air. I believe it is a scientific, accurate, flexible, and effective

policy. Kyoto Protocol 1997, another very effective intervention to reduce greenhouse gases (GHG)

emissions. More than 37 industrial countries committed to reducing GHG emissions to an average of 5%

against 1990 levels (unfccc, 2014). Parties are committed to reducing GHG by 18% from 2013 to 2020.

Some controls of GHS are:

- Flue gas desulfurization (FGD): Inject an alkaline reagent, such as calcium, in the flue gas directly.

This alkaline reagent absorbs, neutralizes, or oxidizes sulfur into calcium sulfate that can be easily

removed from the gas waste.

- Methane from coal mines can be captured and used as an energy resource.

There are some useful strategies to control water pollution such as choose organic fertilizers rather than

chemical ones. Some harmful pesticides have been banned; for example, DDT, Pyrethroids are preferable

pesticides as it is neither persisting nor cause bioaccumulation. Build buffer zones and fences to prevent

erosion, and monitoring of water quality can be achieved by using biological indicators. There are also

many methods to monitor water quality. Critical Path Analysis is the route by which the highest

concentration of pollutants occurs (N. Reeve, 2002). This process helps to predict the pathway of the

pollutant. This will be useful to plan for controlling pollution. TBI (Trend Biotic Indicator); by measuring

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the population of species of organisms in the water. It gives a scale from 0 (very polluted) to 10

(unpolluted). Chandler’s Score is similar to TBI, but it is more detailed and sensitive. It provides a list of

macro-invertebrates. Each group of species is given its own score. BMWP is simpler than Chandler’s rating.

A series of species are grouped into nine blocks according to their sensitivity. Block 1 is for the most

sensitive group, has score 10, and block 9 is for the most tolerant group and has rating 1. BOD (Biological

Oxygen Demand) measures the amount of oxygen in the water that is consumed by organisms. It is

measured at discharge points. Polluted water has inadequate oxygen levels.

There are some useful controls for Soil Pollution. Soil erosion can be controlled by planting a tree to reduce

deforestation. Also, substitute chemical fertilizers by organic ore. Managing solid waste disposal can be

achieved by maintaining the dumping of wastes. Using organic fertilizers instead of chemical fertilizers is

also a method to control soil pollution. Public awareness, and banning toxic chemicals such as DDT are

more efficient ways of controlling soil contamination. Another crucial piece of legislation is the

Environmental Protection Act 1990. I believe it is one of the U.K most important pieces of law as it consists

of 5 functional parts. Part 2 is designated to control and manage wastes as the act prevents disposition,

treating, or disposing of a controlled waste unless a waste management license.

Ionization

Ionization is the process of losing or gaining electrons by the atom or molecules to become an ion. An

example of ionization is salt NaCl. Sodium – Na has only one electron in the outermost orbit, while Chlorine

– Cl has 7 electrons. It needs one electron to be stable. So Na losses his outermost orbit electron and

become negatively charged, and Cl gains this electron and becomes positively charged.

B. Botkin, D., Edward, A. K., 2011, Environmental Science: Earth as Living Planet – 8th Edition, USA, John Wiley & Sons Inc.

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Radiation is the energy traveled through space as it moves through materials or space.

Ionizing Radiation (IR):

It is radiation with sufficient energy to eject electrons from atoms. There are 2 categorize of it; Photons

such as X and gamma radiation and particles such as alpha and beta particles and neutrons. Gamma rays

are produced within the nucleus when they transit from higher energy state to lower energy state. For

example, the decay of the unstable Carbon isotope:

𝐶614 → 𝑁7

14 ∗ + 𝑒− + 𝜇𝑒−

𝑁714 ∗ → 𝑁7

14 + 𝛾

X-rays are similar to gamma rays, but it has less energy. It produced externally when the electrons transit

from higher to the lower energy shell.

Alpha and Beta Particles:

Alpha consists of 2 protons and two neutrons. It can be identified as a helium nucleus 𝐻𝑒24 . It is called the

parent nucleus, for example, the decay of Americium 241 to Neptunium 237

𝑋𝑍𝐴 → 𝑌𝑍−2

𝐴−4 + 𝐻𝑒24

𝐴𝑚95241 → 𝑁𝑝93

237 + 𝛼

Beta particles can be an electron (negatively charged), for example, the decay of Iodine 131 isotope, or

positron (positively charged), for example, the decay of Nitrogen 12 isotope.

𝑋𝑍𝐴 → 𝑌𝑍+1

𝐴 + 𝑒−

𝐼53131 → 𝑋𝑒54

131 + −1𝛽−

𝑋𝑍𝐴 → 𝑌𝑍−1

𝐴 + 𝑒+

𝑁712 → 𝐶6

12 + +1𝛽+

Electrical4u, Ionization Process and definition, [online], http://www.electrical4u.com/ionization-process-and-definition/ ,[Accessed 28/06/2015].

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This IR has an impact on human cells, plants, and the atmosphere. The primary effect of IR on the human

cell is that it breaks DNA. The effect can be direct or indirect. DNA consists of a pair of the interdependent

double strand. Radiation can cut one single strand or both strands. It will be easy to repair it if the radiation

breaks only one strand as the other strand may help improve it, but in the case of both strands break, it

will be challenging to fix. IR can be used to fight cancer cells as it can kill them, but it might also kill the

nearby cells. This can be avoided now by using Tomo-Technology.

The impact of IR on the plant can be concluded below:

- As same as the human cell, it can cause chromosomal abnormality and DNA damage.

- It might affect the growth, reproduction, including sterility and the viability of offspring.

- It might reduce seed germination and mortality.

- It can cause direct burn damages to exposed tissue, and this is most commonly affect.

- It might affect the photosynthesis process and biochemical pathway.

Galactic Cosmic Rays (GCR) and Solar Energetic Particles (SEP) are the primary sources of ionization in the

atmosphere. They affect the chemical-physical processed in the atmosphere as they change the density

of clouds. The cosmic rays in the troposphere and stratosphere produce ultrafine aerosols. These aerosols

form cloud condensation nuclei, which may scatter the solar beam in the forward direction. Cosmic rays

influence the Earth’s atmosphere through electrification of the thunderstorm and formation of ice in

cyclones. It also affects the amount of negative space charge near the ground, and it determines the flow

of costs in the initial stages of the storm. The ions produced above cloud devote the charging current

flowing with the downdraft in the cloud.

There are several strategies and interventions to control Radiation. Ionizing Radiation Regulation 1999

(UK) is an excellent legal framework as it is established to monitor the exposure of IR arising from work

activities. It is the leading local Act in order to determine requirements for the use and control of IR. I like

it as there are some parts I can say that it is beneficial like risk assessment and accident preparedness. EU

Directive (97/43/Euratom) is a directive of protection of the individual against IR effects. It is an excellent

directive as it sets basic safety standards for the protection of worker health and general public health

against IR effects. It requires the approval of specific medical procedures by the relevant authority.

(American Conference of Governmental Industrial Hygienists) ACGIH, while ACGIH sets the Threshold

Limit Value (TLVs) that are used in several jurisdictions, occupational exposure limits. For example, 20mSv-

TLV for the average annual dose for radiation workers, the average over five years, and 1mSv- the

recommended annual dose for the general public (Sulphey & Safeer, 2011).

Human Population:

Overpopulation is one of the main reasons of pollution. The population of Earth has over 7 billion people

(Lugolobi, 2014). Humans need resources and services for their daily activities. Non-renewable resources

are the most used resources; food, water, land and minerals are about to deplete due to overpopulation.

The developed countries with high incomes consume resources more than poor countries, and they

generate more pollution. This increase in pollution may cause diseases and death. The world population

growth is said to be exponential growth, as favorable conditions are available to people to grow. According

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to 2010, US statistics show that it has about 5% of the world’s population who consumes about 25% of all

the world’s resources. This is called Consumption overpopulation (Lugolobi, 2014). This consumption

overpopulation will affect per capita resource demands. The depletion of resources increases as the

population increases. For example, fossil fuels are now depleted. In most less developed countries, land,

water and food are the central crisis for them.

Agroecosystems:

They are ecosystems that have been deliberately simplified by people for the purpose of the production

of species goods of value to humans (Conway, 1993: Sulphey & Safeer, 2015). Agroecosystem energy flow

is different than the natural ecosystem as it depends on human interference.

Characteristics of agroecosystem:

- The nutrient cycle is minimal.

- Self-reproducing of the population of crops plants are very rare.

- It is more suitable and less flexible than a natural ecosystem.

Manipulation of food species:

The human tries to use some techniques in all his life fields to improve his life. Agriculture is one of those

fields. Manipulation is a technique of enhancing a crop of food or a trait of the animal. There are many

techniques of manipulation:

Genetic Engineering:

It is a modification of the organism’s genome by adding new DNA manually to an organism to improve an

organism’s trait. It is called genetic modification (GM). Techniques can be provided by the physical

removal of the gene from an organism and insert it into another.

The advantages are it can prevent most diseases and illnesses; it is also can provide massive amounts of

food and nutrition, and it might help to decrease the uses of pesticides and protect the crops. However,

it has some drawbacks as it has a different taste than natural food, and it can be used as a weapon by

producing poisoned food or to generate harmful diseases.

Population Control:

People can control the crop population by using manipulation techniques. It might happen by separate

males and females and monitor their breeding. The breeding can be controlled by choosing the suitable

place and time for it.

Monoculture Agriculture:

It means that the vegetation is composed of single species or crops. It is useful to reduce plant competition

for nutrients, space, and solar radiation (ECIFM, 2010). It can be used to control unwanted organisms and

reduce the costs of hiring or buying the required machines for arable operations. However, it can be

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harmful as it can deplete nitrogen levels in the soil. The absence of genetic variation can create diseases.

It has been proven that it causes environmental damages.

Artificial or Selective Breeding:

It is a process of breeding an animal or a plant to get particular traits. There are three types of breeding:

inbreeding- between two strictly genetic related species, outbreeding- breeding of two unrelated species,

and cross-breeding- mixing of two different species to produce a hybrid one with all the best

characteristics of parent species. Examples of selective breeding in plants: Broccoli, cabbage, and kale.

Data is used to identify the effectiveness of any policy or strategy. Some of these successful strategies are:

Kyoto Protocol:

As one of the most important strategies to control pollution, the Kyoto Protocol succeeded in reducing

CO2 emissions in Europe by 4.7%, reduce European emissions by 5-14% (Van Vuuren, 2007).

Country Target from 1990-2008/2012

EU-15 -8%

US -7%

Canada, Hungary, Japan, Poland -6%

Croatia -5%

New Zealand, Russia, Ukraine 0%

Norway +1%

Australia +8%

Iceland +10%

As per the Kyoto Protocol annual report 2013, the CO2 emissions amounted to 22.3% lower than 1990

levels.

Clean Air Act 1970:

The annual national emissions have decreased since 1990. The highest percentage drop is for the lead.

Direct PM2.5 emissions have decreased by more than 50%, PM10 and SO2 emissions have declined by 60%,

and NOx and VOC emissions have dropped by 40% (EPA, 2011). I think this is a great achievement that

resulted from the Clean Air Act in the US.

Environmental Act, 1995:

From the air quality statistics in the UK from 1987 to 2014:

- Decreases in urban background particulate pollution PM10 has been recorded in 2014 = 17 µgm-3,

a new low since 1992.

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- The average concentrations of roadside particulate pollution have decreased to 19µgm -3 in 2014,

a new low since 1996.

- A long-term improvement in urban background ozone pollution. The daily 8-hours concentrations

decreased to 61µgm-3 in 2014 since 1987.

These are significant improvements in the air pollution emission concentration that have been achieved

by this act.

Conclusion

Controlling pollution is not a mission impossible. It just needs effective strategies to be implemented.

These strategies must be evaluated by using data. The study of pollution behavior helped scientists to

expect the pathway of it and to control all types of contamination; however, there are some places that

pollution has not been controlled.

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