The Air Quality in Chile: and F

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by Luis Díaz-Robles, Herman Saavedra, Luis Schiappacasse, The Air Quality in Chile: and F. Cereceda-Balic Today, with a population of 16 million, Chile is one of South America’s most Luis Díaz-Robles, 1 Herman Saavedra, and stable and prosperous nations. It leads Latin America in human development, Luis Schiappacasse are competitiveness, income per capita, globalization, economic freedom, low per- with the Air Quality Unit at the Catholic University ception of corruption, and state of peace.2 It also ranks high regionally in terms of Temuco in Chile. F. Cereceda-Balic is with of freedom of the press and democratic development. Its economy is recovering CETAM at the Universidad Técnica Federico Santa fast from the last global economy recession, growing by 5.2% in 2010. The María in Chile. E-mail: Monthly Economic Activity Grow Index for March 2011 was 15.2%, the highest [email protected]. 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.

Cerro Alegre Hill, Valparaiso, Chile.

Geography and Climate subtropical anticyclone marks for much of the year Chile occupies a long, narrow coastal strip between the emergence of the phenomenon of temperature the Andes Mountains to the east and the Pacific inversion and a heavy coastal fog (called “vaguada Ocean to the west, with small mountains in the costera” in Spanish). This favors the generation of center of the country, called the Coast Mountains. a very stable layer of air near the surface, which Its climate varies, ranging from the world’s driest inhibits turbulence and vertical air movement in desert in the north, through a Mediterranean-like these basins. climate in the central region, to a rainy climate in the south. The northern desert contains great mineral During the summer, surface heating allows the ero- wealth. The relatively small central region dominates sion of the inversion layer on the airshed, resulting in terms of population and agricultural resources, in a significant improvement in ventilation. However, where the main cities are located between the emissions of nitrogen oxides (NOx) and volatile Map of Chile. Andes and the Coast Mountains. Southern Chile organic compounds (VOCs) mainly from mobile is rich in forests and grazing lands and features a sources, as well as the solar radiation, favor the string of volcanoes and lakes. formation of ozone in the cities of Santiago and Rancagua in central Chile. This article presents an Weather patterns of the majority of cities in Chile overview of the Chilean air quality standards and located in the central depression are detrimental to the regions that are in exceedance of the air quality the pollutants removal from airshed, especially standards, as well as a broad picture of the air quality during fall and winter. The presence of the Pacific trends in Chile based on available monitoring data.

Table 1. Chilean National Ambient Air Quality Standards.

Primary Standards Secondary Standards Pollutant Level Averaging Time Level Averaging Time CO 9 ppm (10 mg/m3) 8-hr a None None 26 ppm (30 mg/m3) 1-hr a Pb 0.5 μg/m3 b Annual (arithmetic average) None None

c NO2 53 ppb Annual (arithmetic average) None None 213 ppb 1-hr d None None

3 e PM10 150 μg/m 24-hr None None 50 μg/m3 Annual f (arithmetic average) None None

3 e PM2.5 50 μg/m 24-hr None None 20 μg/m3 Annual f (arithmetic average) None None

g O3 0.061 ppm 8-hr None None

h h SO2 0.031 ppm Annual (arithmetic average) 0.031 ppm North Zone Annual (arithmetic average) 0.096 ppm 24-hr i 0.023 ppm South Zone none 0.140 ppm North Zone 24-hr j 0.099 ppm South Zone 0.382 ppm North Zone 1-hr k 0.268 ppm South Zone

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.

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 pollutant 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), Figure 1. Annual minimum, Chilean Standards respectively. These plans are similar in scope to the maximum, and mean aver- The Chilean Air Quality Standards have been U.S. State Implementation Plans (SIPs). age SO2 concentrations defined (and have not changed) since 1994, due to based on 12 sites in the the creation of CONAMA (the Chilean equivalent Latent and Saturated Areas in Chile northern and central regions of the U.S Environmental Protection Agency) the The atmospheric contamination problem was, for of Chile, 1993 to 2009. same year, and set both primary and secondary many years, almost exclusively limited to Santiago; concentration limits for air pollutants. The primary however, many mining zones and other northern, standards are designed to protect the human central, and southern cities in Chile have begun to

Table 2. Chilean zones with severe air quality problems.

Region Area Designation Pollutants Plan/Year a Northern Chile

Antofagasta Tocopilla City Saturated Zone, 2007 PM10 ADP in elaboration

Antofagasta Surrounding zone of CODELCO’s Saturated Zone, 1991 PM10, SO2 ADP, 1993, 2001 Chuquicamata Foundry

Atacama Surrounding zone of CODELCO’s Potrerillos Saturated Zone, 1997 PM10, SO2 ADP, 1999 Foundry, Salvador Division

Atacama Surrounding zone of Hernán Videla Lira Saturated Zone, 1993 SO2 ADP, 1995 Foundry, Tierra Amarilla and Copiapó cities

Coquimbo Andacollo city Saturated Zone, 2009 PM10 ADP in elaboration Central Chile

Valparaíso Vantanas Industiral Complex of Puchuncaví Saturated Zone, 1993 PM10, SO2 ADP, 1993 and Quintero cities

b Metropolitan Region Santiago Metropolitan area Saturated Zone PM10, O3, ADPP , 1996, 2004, of Santiago Latent Zone SO2 NO2 2010

Bernardo O’Higgins Surrounding zone of Caletones Founfry, el Saturated Zone, 1994 PM10, SO2 CODELCO’s el Teniente Division, Mostazal, ADP in elaboration Codegua, Machalí, and Requínoa cities

Bernardo O’Higgins Rancagua city Saturated Zone, 2009 PM10 ADP in elaboration Southern Chile

Maule Talca city Saturated Zone, 2010 PM10 ADP in elaboration Biobío Concepción Metropolitan area Latent Zone, 2007 PM10 APP in process Araucanía Temuco City and Padre Las Casas Saturated Zone, 2005 PM10 ADP, 2010 Notes: aYear enacted and subsequent revision years; bADPP = Atmospheric Decontamination and Prevention Plan.

3030ememaugustaugust 2011 2011 awma.orgawma.org 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 SO2 coming 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 billion by volume (ppbv) 8-hr moving average of Figure 2. Annual average have started showing alarming air quality results, 2009 in Santiago.30 concentrations of PM10 and compared with those from Temuco city.4 These PM2.5 (in µg/m3) in Santi- non-attainment zones cover approximately 40,000 In some southern urban zones, the control meas- ago, Chile, 1989-2009. km2, where approximately 6,800,000 inhabitants ures have not been as successful as in Santiago, are exposed to air pollution. because the sources are different and the ADP began only in 2010. Temuco, for example, has Air Quality Trends serious PM problems due to RWC. Since 2002, The specific geographical and meteorological con- this city has experienced degrading air quality (see ditions of Chile, plus the anthropogenic emissions Figure 2), with PM10 concentrations increasing have resulted in high atmospheric levels of PM10, each year, and exceeding the annual and daily PM2.5, O3 and SO2, and remain a severe problem standards systematically, becoming worse each 31 since the 1990s. As a result, communities exposed year. Temuco’s ADP and the National Strategy to to high concentrations of these pollutants have control de RWC smoke were implemented in Figure 3. Air quality in been associated with a rise in mortality and mor- 2010 to help solve this problem. Temuco (a) PM10 annual bidity.5-29 Fortunately, in some industrial centers and Past Research Focus average and (b) 98 per- cities, pollution levels have drastically decreased by centile and maximum of the measures established in Chilean regulations. and Future Needs 24-hr. For example, the annual SO2 concentrations in the Since 1991, the air quality research in Chile has 32-34 copper mining areas of the north and central focused initially on data analysis, and health Source: Chilean Environmental 21, 26-29 Ministry. regions of Chile decreased substantially (by 77%) effects for short-term exposure. Subsequently, from 1993 to 2009 (see Figure 1). However, the concentrations of SO2 have remained flat or increased 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 O3 is still high with a maximum of 93 parts per awma.org august 2011 em 31 Copyright 2011 Air & Waste Management Association it has expanded to important research topics in areas to further protect human health. While most establishing and improving forecasting models,31, 35-40 of the studies in Chile have focused on PM10, emission inventories and air quality photochemical further analysis should be done for PM2.5 and modeling,41-51 receptor models,52-55 increased studies ultrafine particles, mainly chemical characterization, in health effects for cardio-respiratory diseases pro- aerosols formation, better air pollution control tech- duced by PM and carbon monoxide exposure in nologies, and air quality and local climate change Santiago, Temuco, Talcahuano, and Hualpén,5-15 modeling. policy-making studies,34, 56-61 indoor air quality,56 and chemical description and monitoring net- Chile recently released a new PM2.5 standard, works.32-33, 46, 62-74 which will take effect on January 1, 2012. As we look forward into the future, the importance of While past research has contributed to our under- research cannot be neglected. There is a dire need standing, it is obvious that more research is needed for detailed ambient and source characterization to develop better understanding of the sources and through improved monitoring and modeling their characteristics to aid in better pollution control. efforts thereby helping to meet the challenge. em Owing to the geographical challenges of reducing air pollution in Chile, better air quality management tools are needed in the urban and industrial

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