LET’S CLEAN THE AIR
Caribbean Water and Wastewater Association (CWWA)
Economic Commission for Latin America and the Caribbean (ECLAC)
Inter-American Association of Sanitary and Environmental Engineering (AIDIS)
Organization of American States (OAS)
Pan American Health Organization
World Health Organization (PAHO/WHO)
United Nations Environment Program
Regional Office for Latin America and the Caribbean (UNEP/ROLAC)
AreaofSustainableDevelopmentandEnvironmentalHealth,PAHO/WHO
PanAmericanCenterforSanitaryEngineeringandEnvironmentalSciences, CEPIS/PAHO,2003
CEPISDirector: Dr.MauricioPardónOjeda
Materialpreparedby: Dr.MarceloKorc
Mrs.LourdesMindreau
PRINTED AT CEPIS/PAHO:
Los Pinos 259, Urbanización Camacho, Lima 12, Peru
P.O. Box 4337 - Lima 100, Peru
Telephone: (51 1) 437 1077
Fax: (51 1) 437 8289
cepis@cepis.ops-oms.org
http://www.cepis.ops-oms.org
Introduction
M
!
ore than 30 million children in Latin America and the Caribbean breathe
unhealthy air. If you live or work in a polluted area or environment, you might know a
child affected by dirty air. Common symptoms are soreness in the chest, tearful eyes,
coughing,andheadaches.
According to health professionals, children are more susceptible to air pollution
thanadultsbecause:
Children take in more air in proportion to their
bodyweight and lungsizeandspendmoretimeoutdoorsthanadultsdo.
Children's bodies are developing and are more
susceptibletoirritationsandillnesses.
Some studies have shown that children living in polluted areas or environments
are more susceptible to respiratory infections. Although symptoms may not be
apparent,theyhavehigher probabilityof suffering damages that maycauselossesin lung
function,increasingtheriskofrespiratorydiseasesinadulthood.
The Inter-American Air Quality Day, celebrated on 8 August 2003, is an
opportunity to promotehealthyairforchildren,showingthehazardsofairpollutionand
their impact on children's health, and simple measurestoreduceoreliminate them.We
welcomeyourparticipation inthisinitiative
They are more exposed:
They are more vulnerable:
Let´s protect our children 3
Let´s clean the air
1. Poor airquality. Why?
The air we breathe is mainly composed of nitrogen and oxygen. It contains also
small quantities of other gases such as carbon dioxide, argon, neon, helium, hydrogen,
and methane,andavariableamountofwatervapor.
Air composition is modified
by particles and gases generated by
human activities, primarily the
burning of fossil fuels, such as
petroleum, and the industrialization
of chemical products. When the
changes reach levels that are
hazardous to human health, other
aspects of well-being, and the
environment, we are confronted
with . The most
common pollutants released into
the air or formed within it are
carbon monoxide (CO), sulfur
dioxide (SO ), nitrogen oxides
(NO ), volatile organic compounds
(VOC), ground-level ozone (O ),
and solid and liquid suspended
particles, including heavy metals
such as lead
air pollution
2
x
3
.
Carbonmonoxide (CO)
Sulfur dioxide (SO2)
COis a colorlessandodorless gas. The mainhuman activity that generates COis
the incomplete burning of fossil fuels, such as gasoline. It can be especially hazardous in
cities where the use of old and poorly maintained vehicles, intense traffic, and vehicle
congestion are prevalent. This gas may also be hazardous in enclosed environments that
arepoorlyventilated
SO is a colorless gas generated by the burning of sulfur. The main activities that
generate SO are the burning of fossil fuels and the smelting of minerals with high sulfur
content.
.
2
2
4 Inter-American Air Quality Day
Let´s protect our children 5
Nitrogen oxides (NOx)
3
Volatileorganiccompounds (COV)
Ground-level ozone (O )
Suspendedparticles
The main human activity that generates NO is fuel burningathightemperatures.
Major NO sources include the exhaust pipes of motor vehicles in circulation and the
stacksoffossil-fueledpowerplantsinoperation.
VOC are organic substances, such as benzene and acetaldehyde, which readily
evaporate at temperatures lower than their boiling points. Major VOCsources include
the burning and evaporation of fossil fuels and organic solvents and the emissions
generatedbychemicalproductmanufacturing.
Ground-level ozone is a secondary pollutant formed by a complex series of
chemical reactions of NO and VOC in the presence of sunlight. The variations of O
concentrations in a particular location depend on several factors including the
concentrationsofNO and VOCintheair,intensity of sunlight,weatherconditions, and
topography.
Suspended particles such as ash and dust are usuallyclassified according to their
size. Coarse particles are generated by mechanical means and are typically fragments of
some larger solid particles, whereas fine particles are generated by physicochemical
processes, such as condensation and chemical transformation of gases. In homes, the
main activity that generates suspended particles is the burning of wood, coal, dung, and
kerosene forcookingorheating.
x
x
x 3
x
Lead
2. Howdoes air pollutionaffect children´s health?
Lead is a heavy metal usually released into the air as particles. One of its main
sources istheuseofleadedgasolineinmotorvehicles.
Threeconditionsshouldbeconsideredtoanswerthisquestion:
(1) general healthconditions;
(2) pollutanttypeandconcentration;and
(3) exposure time to contaminated air.
Lungs are very complex
organs containing more than 40
different kinds of cells. Air
pollution can change the cells in
the lung by damaging those that
are most susceptible. If the cells
that are damaged are important in
the development of new
functional parts of the lung, then
the lung may not achieve its full
growth and function as a child
maturestoadulthood.
The incidence of asthma and
other respiratory diseases in
children such as allergic reactions,
bronchitis, and acute respiratory
infections have increased
significantly in the past years. Air
pollution may be one of the
causes.
6 Inter-American Air Quality Day
Eachpollutanthasdifferenteffectsonchildren'shealth
When inhaled, COreacts very rapidly with hemoglobin in the blood and forms
carboxyhemoglobin, decreasing the oxygen delivery to vital organs such as the
heartandthebrain
:
Carbon monoxide(CO)
.
The severity of symptoms depends on the percentage of hemoglobin that
converts to carboxyhemoglobin. After exposures that convert 5 to 10% of the
hemoglobin to carboxyhemoglobin, the child may react more slowly to external
stimuli. At 10 to 30 percent carboxyhemoglobin, nausea, headaches,
unconsciousness and sometimes death can result. Carbon monoxide may also
have prenatal effects.Pregnantwomenwho are exposedtohighlevelsofCOare
at increasedriskofhavinglowbirth-weightbabies.
SO is a very water-soluble gas and therefore most of the SO that is inhaled is
absorbed in the upper respiratory tract provoking nose and throat irritation.
However, small quantities of SO in the alveoli (the deepestpart ofthelungs)can
provokeimportanthealtheffects,primarilyinchildrenwithasthma.
Sulfurdioxide (SO2)
3
2 2
2
Ozone (O )
O is an oxidantthatcan penetratethedeepestregions oftherespiratorysystem
provokingthefollowingsymptoms:
Noseandthroatirritation.
Increased productionofmucousandatendencytocough.
Eyeirritationandheadaches.
During severe pollution episodes, soreness in the chest and difficulty to
breathe indeeplywithoutcoughing
3
.
Let´s protect our children 7
Nitrogenoxides (NO )
Volatileorganiccompounds (VOCs)
Suspendedparticles
Lead
x
Nitrogen dioxide is the most important NO compound withrespect to adverse
health effects. Under most chemical conditions it is an oxidant, as is ozone.
However,itdiffersfromozoneinthatitsuppressesthe immunesystemtoamuch
greaterdegree.
Several studies have shown that children under 5 years of age exposed to high
levels of nitrogen dioxide are more susceptible to respiratory infections and
allergicdisorders.
VOCs may cause different adverse health effects in children. For example several
VOCs, such as benzene, are carcinogenic. Others, such as acetaldehyde, may
irritatethe respiratorytract.
In general, it is difficult to assign a quantitative risk associated with particulate
matter because nearly all studies of its health effects find the presence of other
pollutants that may account for several of the effects. However, the exposure to
this contaminanthasbeen associated withthefollowingoutcomes:
Increased hospitaladmissionsofchildrenwithacuterespiratorysymptoms.
Increased schoolsandkindergartenabsences.
Increased medicationusein childrenwith asthma.
According to several research studies,children with asthma living in a community
with high particle concentrations may have suppressed lung growth. After
children moved into cleaner cities their lung growth returned tothenormal rate,
buttheydidnotrecoverthelostpotentialgrowth.
Lead causes kidney and nerve damage and impairs the body ability to produce
hemoglobin. Lead is often measured in children's blood as an index of
environmental exposure. Several studies have shown that even lowlevels of lead
in the blood of children aged 6-7 years old are linked to measurable decreases in
intelligence quotient.
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8 Inter-American Air Quality Day
3. Howcanwe protect our children?
Helpour childrentobreathe clean air
To protect our children, we should be aware of the air quality in our community
and considerthefollowingsuggestions:
Don't smoke and don't let
others smoke in your
homeorcar.
Keep your home as clean
as possible. Dust, mold,
certain household pests,
secondhand smoke, and
pet dander can trigger
asthma attacks and
allergies.
Prevent children from
being in closed environments
where kitchens or
stoves are inuse.
Limit outdoor activity on
alert days when air
pollution is especially
harmful.
Walk, use bicycles, join or
form carpools, and take
publictransportation.
Limitmotorvehicleidling.
Avoid openburning.
Getkidstestedforleadbytheirdoctororhealthcareprovider.
Protect our childrenfromleadpoisoning
Let´s protect our children 9
Washchildren'shandsbeforetheyeat;washbottles,pacifiers,andtoysoften.
Wash floors and window sills to protect kids from dust and peeling paint
contaminatedwithlead,especiallyinolderhomes.
Use baitsandtrapswhenyoucan;placebaitsandtrapswherekidscan'tgetthem.
Havefuel-burningappliances,furnaceflues,andchimneyscheckedonceayear.
Neverusegasovens or burnersforheat;neverusebarbecuesorgrills indoors or
inthegarage.
Neversleep inroomswithun-ventedgasorkerosenespaceheaters.
Don't run carsinthegarage.
Avoidusing aerosols
Protect our children from carbon monoxide (CO) poisoning
10 Inter-American Air Quality Day
4. Frequentlyaskedquestions
What is the compositionof air?
Whendowe say thatthe air is polluted?
Why are children one of the most sensible populations to
polluted air?
What are the most common air pollutants and how are they
produced?
Theairwebreatheismainlycomposedofnitrogen(78%)andoxygen(21%).Italso
contains small quantitiesofcarbondioxide,othergases,andwatervapor.
Wesaythattheairispollutedwhenits compositionhasbeenalteredand reaches
levels hazardous to human health, other aspects of human well-being, and the
environment.
They are more sensible because they have greater exposure and vulnerability.
They take in more air in relation to their bodyweight and lung size. Besides, they spend
more time outdoors, their bodies are still developing, and are more susceptible to
irritationsandillnesses.
Carbon monoxide (CO); sulfur dioxide (SO ); nitrogen oxides (NO ); volatile
organic compounds (VOCs); ground-level ozone (O ); and suspended particles,
2 x
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Let´s protect our children 11
including heavy metals as lead, are the most common air pollutants. They are generated
mainlybytheburningoffossilfuelsandtheproductiontochemicalproducts.
Health effects will depend on general health conditions, pollutant type and
concentration,and exposuretime.Pollutants may irritate theskin, eyes,andrespiratory
tract; cause kidney and nerve damage; reduce oxygen intake capacity; and produce
cancer.
Let´sbeinformed.
Let´stakepreventiveactions.
Let´sfollowthetipsincludedinthisguide.
How do air pollutants affect children´s health?
What can we do to protect our children from air pollution?
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