Jasmine (5)
2A
12 March 2008
Environmental pollution: Have we done enough?
Pollution
It is the introduction by man into the environment of contaminants that cause harm or discomfort to humans or other living organisms, or damage the environment. Pollution can be in the form of chemical substances, or energy such as noise, heat, or light. Pollutants can be naturally occurring substances or energies, but are considered contaminants when in excess of natural levels. Pollution is often categorized into point source and nonpoint source pollution.
Pollution Control
Pollution control is a term used in environmental management. It means the control of emissions and effluents into air, water or soil. Without pollution controls the undesirable waste products from human consumption, industrial production, agricultural activities, mining, transportation and other sources will accumulate or disperse and degrade the natural environment. In the hierarchy of controls, pollution prevention and waste minimization are more desirable than pollution control.
Some examples are:
Pollution control devices
Dust collection systems
Cyclones
Electrostatic precipitators
Baghouses
Scrubbers
Baffle spray scrubber
Cyclonic spray scrubber
Ejector venturi scrubber
Mechanically aided scrubber
Spray tower
Wet scrubber
Sewage treatment and Wastewater treatment
API oil-water separators
Sedimentation (water treatment)
Dissolved air flotation (DAF)
Activated sludge biotreaters
Biofilters
Powdered activated carbon treatment
Vapor recovery systems
Major forms of pollution and major polluted areas
The major forms of pollution are listed below along with the particular pollutants relevant to each of them:
Air pollution
It is the release of chemicals and particulates into the atmosphere. Common examples include carbon monoxide, sulfur dioxide, chlorofluorocarbons (CFCs), and nitrogen oxides produced by industry and motor vehicles. Photochemical ozone and smog are created as nitrogen oxides and hydrocarbons react to sunlight.
Water pollution
Water pollution via runoff, leaching to groundwater, liquid spills, wastewater discharges, eutrophication and littering.
Soil Contamination
It occurs when chemicals are released by spill or underground storage tank leakage. Among the most significant soil contaminants are hydrocarbons, heavy metals, MTBE[4], herbicides, pesticides and chlorinated hydrocarbons.
Radioactive contamination, added in the wake of 20th century discoveries in atomic physics. (See alpha emitters and actinides in the environment.)
Noise pollution
Noise pollution, which encompasses roadway noise, aircraft noise, industrial noise as well as high-intensity sonar.
Light pollution, includes light trespass, over-illumination and astronomical interference.
Visual Pollution
It refers to the presence of overhead power lines, motorway billboards, scarred landforms (as from strip mining), open storage of trash or municipal solid waste.
Thermal pollution
It is a temperature change in natural water bodies caused by human influence, such as use of water as coolant in a power plant.
Effects of Pollution
Pollution can also be the consequence of a natural disaster. For example, hurricanes often involve water contamination from sewage, and petrochemical spills from ruptured boats or automobiles. Larger scale and environmental damage is not uncommon when coastal oil rigs or refineries are involved. Some sources of pollution, such as nuclear power plants or oil tankers, can produce widespread and potentially hazardous releases when accidents occur.
In the case of noise pollution the dominant source class is the motor vehicle, producing about ninety percent of all unwanted noise worldwide.
Human health
Adverse air quality can kill many organisms including humans. Ozone pollution can cause respiratory disease, cardiovascular disease, throat inflammation, chest pain, and congestion. Water pollution causes approximately 14,000 deaths per day, mostly due to contamination of drinking water by untreated sewage in developing countries. Oil spills can cause skin irritations and rashes. Noise pollution induces hearing loss, high blood pressure, stress, and sleep disturbance.
Ecosystems
Sulfur dioxide and oxides of nitrogen can cause acid rain which reduces the pH value of soil.
Soil can become infertile and unsuitable for plants. This will affect other organisms in the food web.
Smog and haze can reduce the amount of sunlight received by plants to carry out photosynthesis.
Invasive species can out compete native species and reduce biodiversity. Invasive plants can contribute debris and biomolecules (allelopathy) that can alter soil and chemical compositions of an environment, often reducing native species competitiveness.
Biomagnification describes a situation where toxins may be pass through trophic levels, becoming exponentially more concentrated in the process.
So…
From what we can see,there is still a lot of pollution going on.If we can play our part in helping the environment like recycling plastic bottles instead of throwing it anyhow in a place,we can reduce rubbish.We can also prevent global warming from progressing further by cutting down less trees and reduce burning and recycle paper.So help the environment by reducing pollution today!
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