The air quality in Chile: Twenty years of challenge

Abstract

Today, Chile (16 million people) is one of South America's most stable and prosperous nations.1 It leads Latin America in human development, competitiveness, income per capita, globalization, economic freedom, low perception of corruption and state of peace.2 It also ranks high regionally in freedom of the press and democratic development. Its economy is recovering fast from the last global economy recession, growing by 5.2% in 2010. The Monthly Economic Activity Grow Index of March 2011 was 15.2% compared with March 2010, the highest value since 1992.3 In May 2010, Chile became the first South American country to join the Organization for Economic Co-operation and Development, (OECD). However, Chile has serious air quality problems, mainly aerosols.

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28 em august 2011 awma.org
Copyright 2011 Air & Waste Management Association
28 em august 2011 awma.org
em • feature
by Luis Díaz-Robles,
Herman Saavedra,
Luis Schiappacasse,
and F. Cereceda-Balic
Luis Díaz-Robles,
Herman Saavedra, and
Luis Schiappacasse are
with the Air Quality Unit
at the Catholic University
of Temuco in Chile.
F. Cereceda-Balic is with
Environmental Technology
Center (CETAM in Spanish)
at the Universidad Técnica
Federico Santa María in
Chile. E-mail: ldiaz@uct.cl.
Today, with a population of 16 million, Chile is one of South America’s most
stable and prosperous nations.1It leads Latin America in human development,
competitiveness, income per capita, globalization, economic freedom, low per-
ception of corruption, and state of peace.2It also ranks high regionally in terms
of freedom of the press and democratic development. Its economy is recovering
fast from the last global economy recession, growing by 5.2% in 2010. The
Monthly Economic Activity Grow Index for March 2011 was 15.2%, the highest
value since 1992.3In May 2010, Chile became the first South American country
to join the Organization for Economic Co-operation and Development (OECD).
However, Chile has serious air quality problems.
The Air Quality in Chile:
Cerro Alegre Hill,
Valparaiso, Chile.

awma.org august 2011 em 29august 2011 em 29
Geography and Climate
Chile occupies a long, narrow coastal strip between
the Andes Mountains to the east and the Pacific
Ocean to the west, with small mountains in the
center of the country, called the Coast Mountains.
Its climate varies, ranging from the world’s driest
desert in the north, through a Mediterranean-like
climate in the central region, to a rainy climate in
the south. The northern desert contains great mineral
wealth. The relatively small central region dominates
in terms of population and agricultural resources,
where the main cities are located between the
Andes and the Coast Mountains. Southern Chile
is rich in forests and grazing lands and features a
string of volcanoes and lakes.
Weather patterns of the majority of cities in Chile
located in the central depression are detrimental to
the pollutants removal from airshed, especially
during fall and winter. The presence of the Pacific
subtropical anticyclone marks for much of the year
the emergence of the phenomenon of temperature
inversion and a heavy coastal fog (called “vaguada
costera” in Spanish). This favors the generation of
a very stable layer of air near the surface, which
inhibits turbulence and vertical air movement in
these basins.
During the summer, surface heating allows the ero-
sion of the inversion layer on the airshed, resulting
in a significant improvement in ventilation. However,
emissions of nitrogen oxides (NOx) and volatile
organic compounds (VOCs) mainly from mobile
sources, as well as the solar radiation, favor the
formation of ozone in the cities of Santiago and
Rancagua in central Chile. This article presents an
overview of the Chilean air quality standards and
the regions that are in exceedance of the air quality
standards, as well as a broad picture of the air quality
trends in Chile based on available monitoring data.
awma.org
Pollutant
CO
Pb
NO2
PM10
PM2.5
O3
SO2
Level
9 ppm (10 mg/m3)
26 ppm (30 mg/m3)
0.5 μg/m3 b
53 ppb c
213 ppb
150 μg/m3
50 μg/m3
50 μg/m3
20 μg/m3
0.061 ppm
0.031 ppm
0.096 ppm
none
Averaging Time
8-hr a
1-hr a
Annual (arithmetic average)
Annual (arithmetic average)
1-hr d
24-hr e
Annual f(arithmetic average)
24-hr e
Annual f(arithmetic average)
8-hr g
Annual h(arithmetic average)
24-hr i
Level
None
None
None
None
None
None
None
None
None
0.031 ppm North Zone
0.023 ppm South Zone
0.140 ppm North Zone
0.099 ppm South Zone
0.382 ppm North Zone
0.268 ppm South Zone
Averaging Time
None
None
None
None
None
None
None
None
None
Annual h(arithmetic average)
24-hr j
1-hr k
Primary Standards
Table 1. Chilean National Ambient Air Quality Standards.
Secondary Standards
Notes: aThe three-year average of the 99th percentile of the daily maximum 8-hr or 1-hr concentration must not exceed 9 parts per million (ppm) or 1 ppm, respectively. bThe
two-year average concentration must not exceed 0.5 μg/m3. cThe three-year average concentration must not exceed 53 parts per billion (ppb). dThe three-year average of the
99th percentile of the daily maximum 1-hr average must not exceed 213 ppb. eNot to be exceeded more than seven times per year. fThe three-year average of the weighted
annual mean concentration must not exceed the standard. gThe three-year average of the 99th percentile of the daily maximum 8-hr average must not exceed 61 ppb. hThe
three-year average of the weighted annual mean concentration must not exceed the respective standard. iThe three-year average of the 99th percentile of the 24-hr concentrations
must not exceed 96 ppb. jThe three-year average of the 99.7th percentile of the 24-hr concentrations must not exceed the respective level. kThe three-year average of the
99.73th percentile of the 1-hr concentrations must not exceed the respective level.
Map of Chile.
20 Years of Challenge
Copyright 2011 Air & Waste Management Association

30 em august 2011 awma.org
Region
Northern Chile
Antofagasta
Antofagasta
Atacama
Atacama
Coquimbo
Central Chile
Valparaíso
Metropolitan Region
of Santiago
Bernardo O’Higgins
Bernardo O’Higgins
Southern Chile
Maule
Biobío
Araucanía
Area
Tocopilla City
Surrounding zone of CODELCO’s
Chuquicamata Foundry
Surrounding zone of CODELCO’s Potrerillos
Foundry, Salvador Division
Surrounding zone of Hernán Videla Lira
Foundry, Tierra Amarilla and Copiapó cities
Andacollo city
Vantanas Industiral Complex of Puchuncaví
and Quintero cities
Santiago Metropolitan area
Surrounding zone of Caletones Founfry, el
CODELCO’s el Teniente Division, Mostazal,
Codegua, Machalí, and Requínoa cities
Rancagua city
Talca city
Concepción Metropolitan area
Temuco City and Padre Las Casas
Designation
Saturated Zone, 2007
Saturated Zone, 1991
Saturated Zone, 1997
Saturated Zone, 1993
Saturated Zone, 2009
Saturated Zone, 1993
Saturated Zone
Latent Zone
Saturated Zone, 1994
Saturated Zone, 2009
Saturated Zone, 2010
Latent Zone, 2007
Saturated Zone, 2005
Pollutants
PM10
PM10, SO2
PM10, SO2
SO2
PM10
PM10, SO2
PM10, O3,
SO2NO2
PM10, SO2
PM10
PM10
PM10
PM10
Plan/Year a
ADP in elaboration
ADP, 1993, 2001
ADP, 1999
ADP, 1995
ADP in elaboration
ADP, 1993
ADPP b, 1996, 2004,
2010
ADP in elaboration
ADP in elaboration
ADP in elaboration
APP in process
ADP, 2010
Table 2. Chilean zones with severe air quality problems.
30 em august 2011 awma.org
Chilean Standards
The Chilean Air Quality Standards have been
defined (and have not changed) since 1994, due to
the creation of CONAMA (the Chilean equivalent
of the U.S Environmental Protection Agency) the
same year, and set both primary and secondary
concentration limits for air pollutants. The primary
standards are designed to protect the human
health, while the secondary standards are designed
to protect the ecosystems (see Table 1).
Similar to the United States, areas that are in
exceedance of the standards are designated as
non-attainment areas. The designation of a non-
attainment area contains the precise geographic
area it spans. But there are some differences
between the United States and Chile. In Chile, an
area is designated as a “latent” non-attainment
area, when the pollutant concentrations are
between 80 and 100% of the standard, and as a
“saturated” non-attainment area, when the pollu-
tant concentration exceeds the set standard. These
designations of latent or saturated area form the
basis of the atmospheric prevention plans (APP)
or atmospheric decontamination plans (ADP),
respectively. These plans are similar in scope to the
U.S. State Implementation Plans (SIPs).
Latent and Saturated Areas in Chile
The atmospheric contamination problem was, for
many years, almost exclusively limited to Santiago;
however, many mining zones and other northern,
central, and southern cities in Chile have begun to
Notes: aYear enacted and subsequent revision years; bADPP = Atmospheric Decontamination and Prevention Plan.
Figure 1. Annual minimum,
maximum, and mean aver-
age SO2concentrations
based on 12 sites in the
northern and central regions
of Chile, 1993 to 2009.
Copyright 2011 Air & Waste Management Association

awma.org august 2011 em 31
Copyright 2011 Air & Waste Management Association
show air quality problems, with severe health con-
sequences for the population. Table 2 shows that
the atmospheric contamination problem in the
main non-attainment regions in Chilean urban and
mining northern zones is largely due to the high
levels of sulfur dioxide (SO2) and particulate matter
(PM10) from copper foundries and coal-burning
power plants; in the central zone, the concerns are
due to PM10, ozone (O3), and SO2coming from
mobile and point sources; while in Chilean southern
urban zones, the main pollutant is PM10 produced
by residential wood combustion (RWC). Besides
these zones that have been declared as saturated
or latent, there are some cities in southern Chile
(e.g., Chillán, Coyhaique, Talca, Valdivia, and Osorno),
where PM10 monitoring studies and campaigns
have started showing alarming air quality results,
compared with those from Temuco city.4These
non-attainment zones cover approximately 40,000
km2, where approximately 6,800,000 inhabitants
are exposed to air pollution.
Air Quality Trends
The specific geographical and meteorological con-
ditions of Chile, plus the anthropogenic emissions
have resulted in high atmospheric levels of PM10,
PM2.5, O3and SO2, and remain a severe problem
since the 1990s. As a result, communities exposed
to high concentrations of these pollutants have
been associated with a rise in mortality and mor-
bidity.5-29 Fortunately, in some industrial centers and
cities, pollution levels have drastically decreased by
the measures established in Chilean regulations.
For example, the annual SO2concentrations in the
copper mining areas of the north and central
regions of Chile decreased substantially (by 77%)
from 1993 to 2009 (see Figure 1). However, the
concentrations of SO2have remained flat or in-
creased from 2004 to 2009 due to the construc-
tion of more coal power plants as a result of the
expansion of the copper industry and its demand
for energy.
Figure 2 shows the evolution of air quality in San-
tiago, from 1989 to 2009, where annual average
concentrations of PM10 and PM2.5 decreased by
33% and 54%, respectively. The percentage of
PM10 reduction was less than PM2.5 because the
coarse fraction emitted by non-point sources (like
RWC) has experienced an increase of 11%. The
O3is still high with a maximum of 93 parts per
billion by volume (ppbv) 8-hr moving average of
2009 in Santiago.30
In some southern urban zones, the control meas-
ures have not been as successful as in Santiago,
because the sources are different and the ADP
began only in 2010. Temuco, for example, has
serious PM problems due to RWC. Since 2002,
this city has experienced degrading air quality (see
Figure 2), with PM10 concentrations increasing
each year, and exceeding the annual and daily
standards systematically, becoming worse each
year.31 Temuco’s ADP and the National Strategy to
control de RWC smoke were implemented in
2010 to help solve this problem.
Past Research Focus
and Future Needs
Since 1991, the air quality research in Chile has
focused initially on data analysis,32-34 and health
effects for short-term exposure.21, 26-29 Subsequently,
Figure 2. Annual average
concentrations of PM10 and
PM2.5 (in µg/m3) in Santi-
ago, Chile, 1989-2009.
Figure 3. Air quality in
Temuco (a) PM10 annual
average and (b) 98 per-
centile and maximum of
24-hr.
Source: Chilean Environmental
Ministry.

32 em august 2011 awma.org
Copyright 2011 Air & Waste Management Association
areas to further protect human health. While most
of the studies in Chile have focused on PM10,
further analysis should be done for PM2.5 and
ultrafine particles, mainly chemical characterization,
aerosols formation, better air pollution control tech-
nologies, and air quality and local climate change
modeling.
Chile recently released a new PM2.5 standard,
which will take effect on January 1, 2012. As we
look forward into the future, the importance of
research cannot be neglected. There is a dire need
for detailed ambient and source characterization
through improved monitoring and modeling
efforts thereby helping to meet the challenge. em
it has expanded to important research topics in
establishing and improving forecasting models,31, 35-40
emission inventories and air quality photochemical
modeling,41-51 receptor models,52-55 increased studies
in health effects for cardio-respiratory diseases pro-
duced by PM and carbon monoxide exposure in
Santiago, Temuco, Talcahuano, and Hualpén,5-15
policy-making studies,34, 56-61 indoor air quality,56
and chemical description and monitoring net-
works.32-33, 46, 62-74
While past research has contributed to our under-
standing, it is obvious that more research is needed
to develop better understanding of the sources and
their characteristics to aid in better pollution control.
Owing to the geographical challenges of reducing
air pollution in Chile, better air quality manage-
ment tools are needed in the urban and industrial
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