Knowledge, attitudes, and practices of tertiary education students in regard to air pollution in Windhoek, Namibia: a cross sectional study

Background: Knowing the residents' knowledge, attitude, and practices to air pollution is necessary for developing interventions specific to that population. Air pollution remains a neglected environmental concern in Windhoek, Namibia and people’s perceptions about air pollution and health have not been documented. This study investigated the knowledge, attitudes and practices of tertiary students to air pollution in Windhoek. Methods: Students from five tertiary institutions in Windhoek, Namibia were included in cross sectional study. A previously validated structured questionnaire; designed to collect information on knowledge, attitudes, and practices regarding air pollution was used to collect data from 321 randomly selected study participants. Results: More than half (59.4%) of the study participants thought that air pollution was a major problem, while over 90% knew that air pollution could negatively impact health. The media was found to be the main source of information for study participants (91.1%). Despite having the knowledge, less than a third (27%) of the respondents regularly took action out of concern of air pollution. There was a statistically significant association between knowledge, attitudes, and practices to air pollution (all P < 0.05). Conclusions: Air pollution interventions targeting tertiary students should be aimed at informing them on ways in which they could contribute individually and collectively to reducing air pollution and its negative effects.

pollution includes an increased burden of heart and lung diseases, respiratory diseases, infant and child mortality, Skin diseases, allergic reactions, cancer, and increased hospital admissions [3][4][5].
The World Health Organization (WHO) estimated that 9 out of 10 people in the world breathe polluted air, and at least seven million people worldwide die annually as a result of exposure to air pollution [1,6]. The burden of diseases associated with air pollution has a more severe impact than the combination of smoking, diabetes and road accidents [2,[6][7][8]. In 2016, 4.2 million people died from outdoor; and 3.8 million from indoor air pollution related-illness, mainly in low and middle-income countries [2,7,8]. Air pollution effects have gone far beyond affecting human health. Recent studies indicate that it is also affecting the tourism industry and school attendance; which has been observed that high level of smog causes people to stay indoors, and that tourists avoid highly polluted cities [9,10].
Some countries such as China have made significant progress in reducing the level of air pollution within their highly affected cities. This was done through targeted regulations as well as educating the community to combat air pollution [11,12]. The change in people's knowledge, attitudes, and practices to air pollution has contributed to the improvement of air pollution regulations in some cities in China [12,13].
On the other hand, few sub-Sahara African (SSA) countries have prioritised the prevention and control of air pollution, despite sufficient scientific evidence linking air pollution to adverse health effects [14]. The common belief that air pollution only affects the megacities of the world is far from reality. Many cities in Africa are experiencing a deterioration in air quality standards [14]. Although some African countries have regulations in place to control air pollution and institutions for monitoring the air quality, those institutions are not yet efficient enough to yield the desired outcomes [18,19].
The health and environmental implications of air pollution in Africa is not fully understood due to limited data on air pollution. Rapid population growth has increased utilisation of motor vehicles, while rapid industrialisation has been associated with an increase in air pollution levels in SSA. Globally, the largest particulate matter (PM) proportion in air was recorded in SSA [7,14]. In Namibia, air pollution has not been not considered to be a major problem because the population is small, vehicle density is low; and other sources of indoor air pollution in rural villages are considered insignificant, despite the fact that the effects of air pollution were observed to have increased from 10% to 15% [15,16]. Due to the potentially high level of air pollution in many African cities, the burden of the disease linked to air pollution might be underestimated and this area remains understudied [16].
A study investigating the knowledge, attitude and practices (KAP) of tertiary students in regard to air pollution in Namibia could assist with the design of areabased interventions in the City of Windhoek (CoW).

Methods
A quantitative research methodology approach with a descriptive cross-sectional study design was used. A validated questionnaire used was adopted from a study on environmental concerns [20]. The questionnaire tool was adjusted based on the study population and settings., and it was subjected to pre-testing prior to data collection. The respondents for the pilot study were students from two tertiary institutions. A total of twenty (20) questionnaires were distributed during the pilot study. The tool was then refined based on the recommendations and observations from the pre-testing.
The data collection tool consisted of 23 questions that required approximately 10-15 minutes complete. The questions were divided into three sections. Section A was about respondent's general information (question 1-6), section B was the general environmental concerns (question [7][8][9][10][11][12][13][14][15][16][17][18][19][20], and section C was the perceptions and attitude towards air pollution (question [21][22][23]. The questionnaire consisted of questions that assessed knowledge of air pollution, perceptions, and attitude towards air pollution. In order to assess knowledge, questions related to knowledge were identified and for each correctly answered question, a score of 1 was allocated. A score of 5 out of 10 was considered an acceptable level of knowledge of air pollution in Namibia.
Selection of students was based on the following criteria; 18 years old and above who were registered for a full-time diploma or degree at any tertiary institution in Windhoek. Students who met the above criteria were randomly invited to participate in the study and were informed of the date and venue for information sharing.
During the recruitment process, a random sampling approach was used to select the study participants [21]. All students who turned up to the information sharing session and were willing to take part in the study were given a questionnaire to complete. According to Muindi et al, the prevalence of community perceptions of air pollution and related health risks in Nairobi slums was 20% [22]. This information was used to estimate the p that was used to calculate the sample size. The q = 1-p = 1-0.2 = 0.8. The desired margin of error for this study was 5%.
The inclusion criterion for selection of institutions was that they had to be accredited by the Namibia Qualification Authority (NQA) to offer an undergraduate diploma or degree courses full-time. At the time of the study, ten (10) tertiary institutions in Windhoek were offering accredited diploma or degree courses on a full-time basis [23]. Institutions were approached for permission to conduct this study with their students, and data collection was only done with students from those institutions which permitted this study. The number of student per institution was determined as follows; sample size divided by the number of institutions which granted permission to participate in the study.
Data was initially captured in Epi Data Entry by the assistant researcher, and then double entry verification was done by the researcher. Data verification step was taken if there was any information mismatch when comparing it with the responses from the original questionnaire. The data in the double-entry file was used as final, which was then exported to Microsoft Excel, and Stata version 15. Frequency and a corresponding percentage were reported for categorical data, whereas the association between knowledge of air pollution and perceptions was evaluated using the Chi-square test. Kruskal Wallis rank test was used to assess the statistical difference in knowledge, attitudes and practices. Data analysis was performed using STATA 15 and evaluated at a 5% level of significance.

Demographic characteristics of the study participants
The study collected data from a total of 321 respondents, a 100% response rate was obtained from respondents from five different tertiary institutions. A total of 176 (54.8%) of the sample were female, 234 (72.9%) were between the age of 18-23 years old, and a total of 10 (3.1%) were over the age of 34 years old. The majority (128, 39.9%) were in their first year of study, with a total of 69 (21.6%) respondents enrolled in the health field (Table 1). The general level of Knowledge Air pollution (208, 69%), litter (139, 43%), and traffic (108, 34%) have been cited as the top three most environmental concern in Windhoek ( Fig. 1). Table 2 presents the measure of association between demographic characteristics and knowledge of air pollution. Over 80% of participants had knowledge about air pollution. There was no statistically significant of an association between gender, year of study and stream of the study with knowledge of air pollution (p > 0.05).    Table 4 presents the measure of statistically significant difference between mean knowledge score, attitude, and behaviour toward air pollution. There was a statistically significant difference between mean knowledge, attitude and behaviour (p < 0.05) except for taking actions out of concern of air pollution (p > 0.09). acknowledged air pollution as a real problem. Although they said, air pollution is inevitable, participants have positive attitudes toward its control as the majority (65.1%, and 28.3%) think that reduction in the effects of air pollution is a collective responsibility (Fig. 2). About 80% of respondents admitted that they would take action if they knew better ways of reducing air pollution. On controlling air pollution, a total of 189 (60.6%) participants agreed that there is a need to penalise all polluting companies, as well as put a strict regulation to monitor car emissions more frequently to ensure that pollution from motor vehicles is minimised.  acknowledged air pollution as a real problem. Although they said, air pollution is inevitable, participants have positive attitudes toward its control as the majority (65.1%, and 28.3%) think that reduction in the effects of air pollution is a collective responsibility (Fig. 2). About 80% of respondents admitted that they would take action if they knew better ways of reducing air pollution. On controlling air pollution, a total of 189 (60.6%) participants agreed that there is a need to penalise all polluting companies, as well as put a strict regulation to monitor car emissions more frequently to ensure that pollution from motor vehicles is minimised.
Participants identified that the most reliable source of air pollution information is

Discussion
The aim of this study was to investigate the knowledge, attitude, and practices of students regarding air pollution in order to suggest air pollution interventions in the CoW. Air pollution, littering and traffic/congestion was identified as the most common environmental concern in the CoW. This is similar to the global and national call for air pollution and climate change to be considered among the priority list of common environmental problems that need to be addressed as a matter of urgency [8, 16,24]. However, according to the official information from the Government Republic of Namibia (GRN), air pollution is not among the most pressing environmental problem in Namibia [15].
Participants perceived air pollution as a major problem and that it had affected them or their family negatively. Their attitude towards air pollution prevention is positive as the majority indicated that they would be willing to contribute to air pollution control measures and also urged the government to take an active role in 13 promoting a healthy environment. There was no statistically significant association between knowledge of air pollution and age, year of study or stream.
Regarding air pollution knowledge, respondents had some basic information and understanding of air pollution. The majority understood that there was an association between air pollution and health problems, with about 60% perceiving that air pollution had affected them in different ways such as having difficulty in breathing, irritation of the eyes; and poor visibility. The effects of air pollution on humans can be short or long term. The short term effects of air pollution can include an allergic reaction, irritation of the eyes and skin; and difficulty in breathing. Whereas the long term effects can be chronic diseases such as asthma, heart diseases, lung cancer, and non-communicable diseases [25][26][27].
Information from research institutions, organisations and media was the most common way of passing on information and interventions pertaining to air pollution and health. Among respondents who were knowledgeable about an association between air pollution and health problems, few regularly took action out of concern to reduce air pollution. This study did not obtain further investigate factors leading to lack of air pollution prevention activities among respondents. However, it has been observed globally that lack of information may lead to poor action [28,29].
This study found that there was a statistical significant association between knowledge, behaviour, and attitudes regarding air pollution (P-values > 0.05).
Increased air pollution awareness among community members can lead to early acceptance of air pollution policies, and interventions as well as a willingness to take protective measures [30, 31].
Although the majority of respondents thought that motor vehicles or bikes were the main cause of air pollution in the CoW, most indicated that they would like to buy a car once they started working. This might have a future implication on the density of motor vehicles within the city, as the increased use of motor vehicles is linked to ambient air pollution [17,32]. A study conducted in South Korea found that carbon monoxide (CO) emissions came from vehicles (35%) and industrial sites (30%), while PM10 was associated with the local automotive industry [32].
There was general agreement among respondents that the fight against air pollution should be a collective effort as they indicated that individuals, the CoW, and The study also investigated factors that could reduce air pollution in the CoW. The majority of the respondents suggested that all polluting companies should be penalised for polluting the environment. More than 90% agreed that car emissions should be checked and controlled more frequently as a measure to reduce air pollution in the city. Over 90% believed that the government needed to do more to promote and encourage a better environment.
The fight for a better environment should, however not be limited to the government alone. Respondents believed that there was a need to involve all stakeholders such as family and friends, the media, environmental organisations, tertiary institutions and researchers. This is in line with other studies, which have emphasised the need for a collective effort in improving the air quality in the city [30].

Limitations
The lack of discussion and regulation on air pollution in the CoW may have a negative effect on the resident's knowledge and practices in regard to air pollution.
The result of this study is therefore based on perceptions from respondents. The data collection tool was adopted from a survey study, the questions were adjusted to fit the study settings, and this could affect or change the theoretical guide used when designing each question. Perception of reducing the effects of air pollution is a collective responsibility

Discussion
The aim of this study was to investigate the knowledge, attitude, and practices of students regarding air pollution in order to suggest air pollution interventions in the CoW. Air pollution, littering and traffic/congestion was identified as the most common environmental concern in the CoW. This is similar to the global and national call for air pollution and climate change to be considered among the priority list of common environmental problems that need to be addressed as a matter of urgency [8, 16,24]. However, according to the official information from the Government Republic of Namibia (GRN), air pollution is not among the most pressing environmental problem in Namibia [15].
Participants perceived air pollution as a major problem and that it had affected them or their family negatively. Their attitude towards air pollution prevention is positive as the majority indicated that they would be willing to contribute to air pollution control measures and also urged the government to take an active role in promoting a healthy environment. There was no statistically significant association between knowledge of air pollution and age, year of study or stream.
Regarding air pollution knowledge, respondents had some basic information and understanding of air pollution. The majority understood that there was an association between air pollution and health problems, with about 60% perceiving that air pollution had affected them in different ways such as having difficulty in breathing, irritation of the eyes; and poor visibility. The effects of air pollution on humans can be short or long term. The short term effects of air pollution can include an allergic reaction, irritation of the eyes and skin; and difficulty in breathing. Whereas the long term effects can be chronic diseases such as asthma, heart diseases, lung cancer, and non-communicable diseases [25][26][27].
Information from research institutions, organisations and media was the most common way of passing on information and interventions pertaining to air pollution and health. Among respondents who were knowledgeable about an association between air pollution and health problems, few regularly took action out of concern to reduce air pollution. This study did not obtain further investigate factors leading to lack of air pollution prevention activities among respondents. However, it has been observed globally that lack of information may lead to poor action [28,29]. This study found that there was a statistical significant association between knowledge, behaviour, and attitudes regarding air pollution (P-values > 0.05). Increased air pollution awareness among community members can lead to early acceptance of air pollution policies, and interventions as well as a willingness to take protective measures [30,31].
Although the majority of respondents thought that motor vehicles or bikes were the main cause of air pollution in the CoW, most indicated that they would like to buy a car once they started working. This might have a future implication on the density of motor vehicles within the city, as the increased use of motor vehicles is linked to ambient air pollution [17,32]. A study conducted in South Korea found that carbon monoxide (CO) emissions came from vehicles (35%) and industrial sites (30%), while PM10 was associated with the local automotive industry [32].
There was general agreement among respondents that the fight against air pollution should be a collective effort as they indicated that individuals, the CoW, and government have the overall responsibility in tackling air pollution. A modern lifestyle characterised by globalisation and industrialisation has led to an increased level of air pollution [7,32]. Respondent's general knowledge of air pollution was good and that they had a positive attitude toward its control. Willingness to participate in air pollution interventions was shown by almost all respondents (> 90), who were willing to take action which could lead to a reduction in air pollution effects. The roles of an individual in the fight against air pollution were found to be crucial in China [31].
The study also investigated factors that could reduce air pollution in the CoW. The majority of the respondents suggested that all polluting companies should be penalised for polluting the environment. More than 90% agreed that car emissions should be checked and controlled more frequently as a measure to reduce air pollution in the city. Over 90% believed that the government needed to do more to promote and encourage a better environment.
The fight for a better environment should, however not be limited to the government alone.
Respondents believed that there was a need to involve all stakeholders such as family and friends, the media, environmental organisations, tertiary institutions and researchers. This is in line with other studies, which have emphasised the need for a collective effort in improving the air quality in the city [30].

Limitations
The lack of discussion and regulation on air pollution in the CoW may have a negative effect on the resident's knowledge and practices in regard to air pollution. The result of this study is therefore based on perceptions from respondents. The data collection tool was adopted from a survey study, the questions were adjusted to fit the study settings, and this could affect or change the theoretical guide used when designing each question.

Conclusions
Understanding people's knowledge of air pollution may help guide responses or communication of information related to air pollution. This paper represents the first study done in Windhoek looking at tertiary students' knowledge, attitude and responses regarding air pollution. There is a need to raise awareness on air pollution among tertiary students, which is aimed at informing them on ways in which they can contribute individually and collectively towards reducing the effects of air pollution. The use of media would be the most effective way of passing information regarding air pollution preventive measures. The government can no longer ignore air pollution on the basis of the small population and low car density, but rather put measures in place which are aimed at controlling air pollution. There is a need for further study to determine the level of air pollution in the city as well as the common pollutants in the city in order to inform specific interventions. Perception of reducing the effects of air pollution is a collective responsibility