General Environmental Pollution Effects
A very important aspect of the effect of pollution is its dose (or concentration) required to cause environmental damage.
The definition of pollution response is “the change in the effect of a pollutant in response to a change in its concentration”.
In this respect, 3 different types of response evoked by the environment to different pollution concentrations:
Linear effect
Greater-than-linear effect
Threshold effect
In the linear effect, environmental damage increases linearly with pollution concentrations. In other words, “ the total damage or risk is directly proportional to the accumulated exposure”.
This effect occurs with radioactive substances as well as mercury, lead, cadmium and asbestos.
In the greater-than-linear effect, environmental damage increases with an increase in pollution concentrations but at a decreasing rate. This means that, as pollution concentrations continue to increase the environmental damage will continue to decrease.
This is the case with thermal pollution.
In the threshold effect, pollution produces no effect until a certain threshold in pollution concentrations is achieved. In other words, “so long as a given threshold is not exceeded, the damage from pollution would be completely repaired as quickly as it is produced”.
This effect is found with biodegradable pollutants.
It is also important to mention synergistic effects of pollutants on the environment. While interacting with each other, pollutants can produce greater impacts than when acting individually.
A good example of that is a synergy between asbestos exposure and smoking in causing lung cancer.
There is no doubt that excessive levels of pollution are causing a lot of damage to human & animal health, plants & trees (including tropical rainforests) as well as the wider environment.
All types of environmental pollution – air, water and soil pollution – have an impact on the living environment.
The effects in living organisms may range from mild discomfort to serious diseases such as cancer to physical deformities (for example, extra or missing limbs in frogs).
Experts admit that environmental pollution effects are quite often underestimated and that more research is needed to understand the connections between pollution and its effects on all life forms.
Environmental Pollution Effects on Humans
We know that pollution causes not only physical disabilities but also psychological and behavioral disorders in people.
We are discussing the effects of air pollution and specific air pollutants in more detail in the Air Pollutants article.
The following effects of environmental pollution on humans have been reported:
Air pollution
Reduced lung functioning
Irritation of eyes, nose, mouth and throat
Asthma attacks
Respiratory symptoms such as coughing and wheezing
Increased respiratory disease such as bronchitis
Reduced energy levels
Headaches and dizziness
Disruption of endocrine, reproductive and immune systems
Neurobehavioral disorders
Cardiovascular problems
Cancer
Premature death
Water pollution
Waterborne diseases caused by polluted drinking water:
Typhoid
Amoebiasis
Giardiasis
Ascariasis
Hookworm
Waterborne diseases caused by polluted beach water:
Rashes, ear ache, pink eye
Respiratory infections
Hepatitis, encephalitis, gastroenteritis, diarrhoea, vomiting, and stomach aches
Conditions related to water polluted by chemicals (such as pesticides, hydrocarbons, persistent organic pollutants, heavy metals etc):
Cancer, incl. prostate cancer and non-Hodgkin’s lymphoma
Hormonal problems that can disrupt reproductive and developmental processes
Damage to the nervous system
Liver and kidney damage
Damage to the DNA
Exposure to mercury (heavy metal):
In the womb: may cause neurological problems including slower reflexes, learning deficits, delayed or incomplete mental development, autism and brain damage
In adults: Parkinson’s disease, multiple sclerosis, Alzheimer’s disease, heart disease, and even death
Note:
Water pollution may also result from interactions between water and contaminated soil, as well as from deposition of air contaminants (such as acid rain)
Damage to people may be caused by fish foods coming from polluted water (a well known example is high mercury levels in fish)
Damage to people may be caused by vegetable crops grown / washed with polluted water (author’s own conclusion)
Soil contamination
Causes cancers including leukaemia
Lead in soil is especially hazardous for young children causing developmental damage to the brain
Mercury can increase the risk of kidney damage; cyclodienes can lead to liver toxicity
Causes neuromuscular blockage as well as depression of the central nervous system
Also causes headaches, nausea, fatigue, eye irritation and skin rash
Note:
Contact with contaminated soil may be direct (from using parks, schools etc) or indirect (by inhaling soil contaminants which have vaporized)
Soil contamination may also result from secondary contamination of water supplies and from deposition of air contaminants (for example, via acid rain)
Contamination of crops grown in polluted soil brings up problems with food security
Since it is closely linked to water pollution, many effects of soil contamination appear to be similar to the ones caused by water contamination
An Extreme Oil Pollution Case
Pollution of pristine Ecuador rainforest by Texaco / Chevron oil corporation represents perhaps one of the most outrageous cases of oil pollution ever.
Some levels of pollutants left by the company on its sites of oil exploration have been calculated to exceed the US safety standards by as much as 1,000 times, causing such side effects as children born with fused fingers and deformed eyes, high cancer rates, etc.
Environmental Pollution Effects on Animals
Air Pollution
Acid rain (formed in the air) destroys fish life in lakes and streams
Excessive ultraviolet radiation coming from the sun through the ozone layer in the upper atmosphere which is eroded by some air pollutants, may cause skin cancer in wildlife
Ozone in the lower atmosphere may damage lung tissues of animals
Water Pollution
Nutrient pollution (nitrogen, phosphates etc) causes overgrowth of toxic algae eaten by other aquatic animals, and may cause death; nutrient pollution can also cause outbreaks of fish diseases
Chemical contamination can cause declines in frog biodiversity and tadpole mass
Oil pollution (as part of chemical contamination) can negatively affect development of marine organisms, increase susceptibility to disease and affect reproductive processes; can also cause gastrointestinal irritation, liver and kidney damage, and damage to the nervous system
Mercury in water can cause abnormal behavior, slower growth and development, reduced reproduction, and death
Persistent organic pollutants (POPs) may cause declines, deformities and death of fish life
Too much sodium chloride (ordinary salt) in water may kill animals.
Note:
We also assume that some higher forms of non-aquatic animals may have similar effects from water pollution as those experienced by humans, as described above (author’s own conclusion)
Soil Contamination
Can alter metabolism of microorganisms and arthropods in a given soil environment; this may destroy some layers of the primary food chain, and thus have a negative effect on predator animal species
Small life forms may consume harmful chemicals which may then be passed up the food chain to larger animals; this may lead to increased mortality rates and even animal extinction
Environmental Pollution Effects on Trees and Plants
Air Pollution
Acid rain can kill trees, destroy the leaves of plants, can infiltrate soil by making it unsuitable for purposes of nutrition and habitation
Ozone holes in the upper atmosphere can allow excessive ultraviolet radiation from the sun to enter the Earth causing damage to trees and plants
Ozone in the lower atmosphere can prevent plant respiration by blocking stomata (openings in leaves) and negatively affecting plants’ photosynthesis rates which will stunt plant growth; ozone can also decay plant cells directly by entering stomata
Water Pollution
May disrupt photosynthesis in aquatic plants and thus affecting ecosystems that depend on these plants
Terrestrial and aquatic plants may absorb pollutants from water (as their main nutrient source) and pass them up the food chain to consumer animals and humans
Plants may be killed by too much sodium chloride (ordinary slat) in water
Plants may be killed by mud from construction sites as well as bits of wood and leaves, clay and other similar materials
Plants may be killed by herbicides in water; herbicides are chemicals which are most harmful to plants
Soil Contamination
May alter plant metabolism and reduce crop yields
Trees and plants may absorb soil contaminants and pass them up the food chain
Environmental Pollution Effects on Wider Environment
Apart from destroying the aquatic life in lakes and streams, acid rain can also corrode metals, damage surfaces of buildings and monuments, and cause soil acidification.
Pollution of water may cause oxygen depletion in marine environments and severely affect the health of whole ecosystems.
Environmental Pollution - Conclusion
Environmental pollution is causing a lot of distress not only to humans but also animals, driving many animal species to endangerment and even extinction.
The transboundary nature of environmental pollution makes it even more difficult to manage – you cannot build stone walls along the borders of your country or put customs cabins at every point of entry to regulate its flows into your country.
Everything on our planet is interconnected, and while the nature supplies us with valuable environmental services without which we cannot exist, we all depend on each other’s actions and the way we treat natural resources.
It’s widely recognised that we are hugely overspending our current budget of natural resources – at the existing rates of its exploitation, there is no way for the environment to recover in good time and continue “performing” well in the future.
Perhaps we should adopt a holistic view of nature – it is not an entity that exists separately from us; the nature is us, we are an inalienable part of it, and we should care for it in the most appropriate manner. Only then can we possibly solve the problem of environmental pollution.
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