Participant: Franklin Lezama- Professor:
Mariana Córdova
Health
and environment
The contamination of the environment results direct
and indirectly on the health of the human beings. The nature does not only influence in the
state of the agency through the air pollution, but also from the subterranean
nappe of drinking water.
Tolerable levels.
"Great part of the world population lives in
areas in which the levels of air pollution exceed the features established by
the world health Organization (WHO) -affirms the doctor Francis Murray, of the
University Murdoch, of
The one that the WHO have established tolerable
levels of these contaminants in the environment themselves due to that have
verified harmful consequences on the health of the people. Nevertheless, the associated illnesses with
the contamination of the environment always are not taken into account: the
respiratory problems, the cardiovascular affections and the cancer are the most
important.
The atmospheric contaminants are not static; on the
contrary, they are transferred of the hand of the wind to far away regions and
they fall on the surface of the planet in the shape of rain, contaminating the
floor, the seas, the rivers, the gaps and even they arrive at the subterranean
nappe.
"The emissions of diverse substances, as for
example the sulfur and the nitrogen, cause diverse inconveniences of the human
health, they can result in direct form on the cell receivers or to alter the
nature of the floors and the water, and thus to cause illnesses in indirect
form", the doctor says Rafael Blacksmith, of the Center of Ecology of the
Venezuelan Institute of Scientific Investigations of Caracas (Venezuela).
Four threats
for the human health
The contaminants substances list that at present are
freed al environment is almost infinite: dioxide of carbon, carbon monoxide,
organic bodies volátiles, leads, benzene,
benzoapireno, ammonia, ozone, dioxide of sulfur, dioxide of nitrogen and in
particles in suspension. All these
substances have a negative impact on our agency. .
We harm for the sulfur: "The dioxide of sulfur is a very soluble
substance in water, and therefore its exposition irritates the mucous membranes
of the nose, the mouth, the pharynx and the bronchial tubes in question of
minutes. Additionally, also it irritates
the respiratory ways, reducing at the same time the pulmonary capacity and
causing hoarseness, respiration cut off and pressure in the chest. The asthmatic they are particularly sensitive
al sulfur", explains the doctor Murray.
As for the particles in suspension, they are freed
for the fossil fuels combustion processes:
"These they can damage the respiratory function, carrying toward
the morbidity and respiratory mortality therefore they irritate the respiratory
tract, tighten the ways of ventilation, they irritate the asthma and the
bronchitis, and they enlarge the rates of respiratory infections -enumerates
the doctor Murray-. Evidences exist in
the
According to this specialist, "The ozone
damages the pulmonary operation, and the effects occur mainly during an
exposition al ozone while the people carry out physical exercises. The studies of field suggest that the
irritation of the eyes, nose, throat, the discomfort in the chest, cough and
headaches can be associates with the high concentrations of ozone in the air. Besides, the asthmatic children to seem to be
in greater risk toward the exposition al ozone".
Finally, the oxides of nitrogen. "The nitrogen oxide gases are toxic for
the humans and they give origin also to the formation of ozone troposphere that
causes impacts in the health and in the vegetation", explains the doctor
Kevin Hicks, of the
"The greater impacts of the dioxide of nitrogen
in the health are the increases in the incident of the infections in the lower
part of the respiratory ways in children and in the decrease of the answer of
the respiratory ways in the asthmatic.
The exposition repeatedly can carry to pulmonary wounds", adds the
doctor Murray.
The oxides of nitrogen (mainly the dioxide) are a
good example of how a first present contaminant in the atmosphere can affect
courses of water and nappe of subterranean drinking water, impacting for
diverse ways the human health.
"The deposition of nitrogen is able acidificar
the terrestrial ecosystems, and the growing concentrations of nitrate in the
sources of drinking water constitute a problem for the human health -explains
the doctor Hicks-. Of some way the
nitrates can be become the stomach certainly microorganisms to nitrite, that al
to be absorbed in the blood converts the hemoglobin in metahemoglobina. The metahemoglobina is not cash in the
transportation of oxygen in the blood and in cases of high sharp or chronic
values can conduct to the death in children by the call syndrome of the blue
baby".
A
global problem
The effects of the environmental contamination
constitute a global problem. Not only
because the substances contaminants can travel from region in region, but
because their presence in the environment responds to countries industrialized
and to developing countries. "The
emissions of contaminants are enlarging in many of the developing countries and
in some areas already have been observed the first impacts on the health",
the doctor says Johan Kuylenstierna, investigator of the
"The developing countries are currently sources
of the regional environmental contamination", confirms the doctor Murray,
and gives an example: "The smog
caused by the fires in the forests of
"In the
majority of the developing countries where the impacts of the environmental
contamination are extensively disseminated, the emissions represent an emerging
event and can be expected that they enlarge substantially in the future. In some cases these will increase
dramatically if itself are not taken the preventive measures that the case
requires", concludes the doctor Kuylenstierna.