Similarly to other Latin American countries, urban air quality is a major concern in Colombia. The purpose of the present study was to explore citizens’ perception on local air pollution, its causes and impacts. A questionnaire was individually applied to a sample of 994 participants. Relationships between demographic features and the perception on air quality were analyzed using a logistic regression, its odds ratio (OR), and a Chi-square test. Eighty percent of the respondents perceive their local air quality as either bad or fair, 65% recognize particulate matter as the main local air pollutant, and 90% recognize negative impacts on people’s health as the main consequence of air pollution. In contrast to other studies where age and economic status are variables highly related with public perception on the level of atmospheric pollution, in this study only the size of the cities has a statistically significant relationship with the perception on local air quality regarding the level of pollution(OR ≥ 1, confidence intervals > 1 and p-values < 0.05). While area sources such as mining and infrastructure construction are identified as the main sources of pollutant emissions in small towns (less than 50,000 inhabitants), in big cities, road traffic is identified as the main source contributor to atmospheric pollution. Opposite to data from official reports, and regardless of the size of the city, households are perceived as the place with greatest contribution to personal air pollution exposure. Results show that citizens are aware of the state of air quality and its health impact is a major concern. Such findings suggest people’s opinions can be used as provisional indicators in cities without data, as well as to monitor the results of local air quality management. As a complementary process, or at the same level of importance given to technical-based policy, citizen participation can contribute to a collective construction of urban air pollution control strategies.
In Colombia, as in other Latin American countries, urban air pollution is a major concern [
Despite these efforts, much is yet to be done towards an improved understanding of the air pollution problem at a local level. While most of the research in Colombia has been focusing on the physical and chemical characterization of the problem, relatively no attention has been given to the socio-cultural aspects that underlie it. For instance, cities have neglected how different actors perceive air pollution problems and what is their level of concern, both individually and collectively.
Different reasons support the incorporation of social factors, in addition to economic and technical analysis, in the design and implementation of air quality policies. A comprehensive air quality management process requires information that reveals implicit socio-cultural aspects and the incorporation of a social value dimension [
In Colombia, there are few researches linking socio-cultural variables to air pollution. Daniels et al. [
Participants were third-year students from Environmental Engineering and Sanitation Technology undergraduate programs on distance-learning-methodology. Students under this learning methodology do not attend classes in a central cam- pus, but follow the academic curriculum from different locations. This allows to have a sample with participants living in diverse cities in Colombia.
The objective population was 1775 people, which corresponds to the total enrolled students in the mentioned academic programs during the time-period of study (October 2014 to November 2015). The statistically representative size of the sample was calculated to be of 667, considering an error of 3%, a confidence level of 95% (α = 0.05) and a distribution of responses of 50%. However, the final sample was made up of 994 participants, geographically distributed as shown in
The questionnaire designed for the study included 15 questions, grouped in three sections: demographic characteristics, recognition of local environmental issues and understanding of the local air pollution condition (see
As suggested by other authors [
Questionnaire responses tabulation and graphical summaries were completed
Section | Question Subject |
---|---|
Demographic characteristics | Name and surname |
Gender | |
Age | |
State | |
City | |
Socioeconomic conditions | |
Local environmental issues | Identification of environmental problems |
Ranking of environmental problems | |
Local air pollution | Perception on Air quality condition |
Emission sources | |
Air pollutants | |
Magnitude of the impacts | |
Impacts description | |
Health related impacts perceived | |
Characteristics of the affected population |
with Microsoft Excel 2016, while statistical analyses were carried out using SPSS v.22 and R v.3.3.1 packages. To examine relationship between demographic cha- racteristics and the perception on air quality a logistic regression was used. The odds ratio (OR) analysis consider that values of OR different than 1, with confidence intervals that do not include that value, express significant levels of association. The Chi-square test was used to assess the level of dependency between the demographic traits having the largest influence on air quality perception (according to the previously estimated OR) and other variables that could be potentially predictors of the local air pollution problem understanding (e.g., pol- lution sources). A p-value less than 5% was the criterion used to consider the test result as statistically significant.
When asking participants about the three-main local environmental issues in their cities or towns of residence, water pollution was included in this list 77.8% of the times, air pollution (together with offensive odors and noise) 74%, inadequate solid waste management 65.3%, and deforestation 35.7%. Other environmental issues mentioned in a lesser extent were soil degradation (29.2%), loss of plant and animal species (11.5%), agrochemicals food contamination (7.8%) and illegal wildlife trade (2.5%). However, when deciding the leading environmental problem in the city, about 40% of the participants selected air pollution among the others (see
Among the 994 responders, 80% perceive their city air quality as either bad or fair (see
Feature | f | % |
---|---|---|
Gender | ||
Female | 600 | 60.4 |
Male | 394 | 39.6 |
Age | ||
<18 | 21 | 2.1 |
18 - 30 | 721 | 72.5 |
31 - 40 | 206 | 20.7 |
>40 | 46 | 4.6 |
Socioeconomic status* | ||
1 | 224 | 22.5 |
2 | 446 | 44.9 |
3 | 279 | 28.1 |
4 | 27 | 2.7 |
5 | 14 | 1.4 |
n/a | 4 | 0.4 |
City size (population) | ||
<50,000 | 287 | 28.9 |
50,000 - 100,000 | 95 | 9.6 |
100,000 - 250,000 | 219 | 22.0 |
250,000 - 500,000 | 123 | 12.4 |
>500,000 | 270 | 27.2 |
*In Colombia, urban areas and its dwellers are classified in six socio-economical strata, with stratum 1 being the lowest and stratum 6 the highest.
Crude Odds Ratio (OR) | |||
---|---|---|---|
OR | 95% CI | p-value | |
Gender | |||
Male to Female | 0.896 | (0.693, 1.158) | 0.404 |
Age | |||
18 < Age ≤ 30 to Age < 18 | 0.797 | (0.329, 1.939) | 0.616 |
30 < Age ≤ 40 to Age < 18 | 0.656 | (1.266, 1.646) | 0.369 |
40 < Age to Age < 18 | 0.916 | (0.318, 2.648) | 0.872 |
Socioeconomic strata | |||
3 - 6 to 1 - 2 | 0.677 | (0.367, 1.256) | 0.214 |
City population (in thousands) | |||
50 < Size ≤ 100 to Size < 50 | 1.641 | (1.032, 2.624) | 0.037 |
100 < Size ≤ 250 to Size < 50 | 2.879 | (1.982, 4.202) | <0.001 |
250 < Size ≤ 500 to Size < 50 | 2.308 | (1.494, 3.585) | <0.001 |
500 < Size to Size < 50 | 7.553 | (5.222, 11.001) | <0.001 |
and two categories respectively. Participants with more than 55 years of age were included in the >40 class and respondents from socioeconomic strata 3, 4, 5 and 6 where grouped to make this class equivalent in terms of size of the sample. With OR ≥ 1, confidence intervals >1 and p-values < 0.05, we found an association between the size of the participant’s city of residence and the perception of high local air pollution. This means a person living in a larger city is likely to have a negative perception on its air quality condition. Other variables such as gender, age and socioeconomic strata showed not statistical significance.
Figures 5-9 show the participant’s perception on other aspects that define the level of understanding of the air pollution problem at a local level. Those aspects included type of pollutant (gases or particles-PM), emission sources, health impacts and places associated with higher levels of air pollution exposure.
According to the Chi-square test level of significance, variables such as “type of contaminant” and “pollution sources” are dependent on the variable “size of the city” (p = 0.02 y p < 0.001, respectively).
More than 90% of the responders perceive air pollution as a negative factor affecting people’s health (see
These results contribute with evidence about citizens’ perception on environmental issues in Latin American urban areas. As well as previous studies [
There is a widespread concern about air quality within the participants. What local environmental authorities have identified regarding air pollution as a major problem in Colombian cities, is also perceived by the community. Contrary to preceding research [
One factor we found associated with participant’s perception was the size of the municipality. With OR different and higher than one, confidence intervals not crossing one and p-values less than 0.05, the bigger the city of residence, the higher the probability to perceive air quality issues. This is consistent with previous research that highlight how town or city features have a significant influence on perceived levels of air pollution at the local level [
Despite most small and mid-sized cities do not have air quality monitoring networks and the fact that in Colombia air quality data is limited [
Other authors have previously remark that air quality problems are especially critical in large cities with high population density [
There is a statistical evidence for the relationship between perception on the emission sources and size of the city (X2 = 166.98, p < 0.001). In general, local area sources and forest fires have more relevance in small cities, while the importance of vehicular traffic as a source of air pollution, rises as the size of the city increases. Industries are more frequently mentioned as the main source of air pollution in mid-size cities (population between 100,000 and 250,000 inhabitants) (
Regarding the consequences of air pollution, although more than 90% of the total responders associated negative impacts on people’s health, those living in major cities were more likely to recognize such harmful effect. Similarly, when asked about the place where people are more exposed to air pollution, participants of the largest cities mentioned roadsides in greater percentage in comparison to those in small and mid-size cities. However, in both small towns and large cities, respondents coincide on the household as the place where they are more exposed to air pollution. Such results reinforce the suggestion about the importance of considering concepts of healthy-home when designing housing projects.
Air pollution problems are complex and multidimensional, which demands to involve different perspectives for its analysis and management [
Citizens’ perception on local air pollution, its causes and consequences were explored in different municipalities in Colombia. Limitations notwithstanding, the authors want to highlight the questionnaire design and implementation process as a replicable instrument for broader studies in Colombia and Latin America. It is motivating the fact that participants were university students since they are call to later hold decision-making positions, in both public and private sectors.
The widespread perception of poor air quality should be a call for the authorities to initiate or intensify monitoring, and emissions control programs. Particulate matter was identified as a critical pollutant and people recognized adverse health effects as a main air pollution impact. Such findings suggest people’s opinion can be a way to have indicators in cities without data, but also a way to track local air quality management. Moreover, this type of data may be used by environmental authorities to prioritize cities/regions to start acting.
This study was funded by in part the Universidad Nacional Abierta y a Distancia (UNAD) in Colombian. The authors especially thank those students who voluntarily agreed to participate in the study by answering the questionnaire.
Ramírez, O., Mu- ra, I. and Franco, J.F. (2017) How Do People Understand Urban Air Pollution? Exploring Citizens’ Perception on Air Quality, Its Causes and Impacts in Colombian Cities. Open Journal of Air Pollution, 6, 1-17. https://doi.org/10.4236/ojap.2017.61001