Implications of Indoor Air Pollution in Business Buildings in Nigeria

.

health, comfort, well-being and productivity. Hence, it is a basic indicator of health quality, comfort and productivity of occupants. Yadav [4], identified that interaction between the construction site, building design, construction techniques, contaminants sources and respondents' activities are among the major factors which influence indoor air quality.
Balmes [5], asserted that Environmental Protection Agency (EPA) ranked IAQ among the top five most significant environmental risks to human health. Kelly and Fussell [6], affirmed that because IAQ occupy a restricted space and the dynamic combination of physical, biological, and chemical factors it can lead to poor IAQ which affect the occupants' health and physical reactions. Other numerous factors that can contribute to poor quality of indoor air as identified by Ahmed [7] are ecological factors, interior and exterior space activities, overcrowding, layout of spaces, and types of materials used in construction and furnishing. The pollutant levels in indoor surroundings might be greater than outside environments.
Furthermore, evidence suggests that volatile organic chemicals commonly present in office indoor air may trigger sick building syndrome symptoms [8].
Study on air attribute has been concentrated on the outside and interior air quality (IAQ) with its consequences receiving significantly less attention until the last decade (Sundell, 2004). Studies have revealed that inside air is further polluted than outside air, which made experts and the general public have focused on the concerns connected with inside ambient attribute [9].
Perpetual alterations in living mode and the supplies utilised in inside surroundings result in considerable changes in the character and intricate formations of inside air contaminants allowing for more extensive analysis [9]. As such, the study seeks to examine the health impact of these contaminants.
Event centres attract large population of users that stay for long hours at a stretch for purposes of social gatherings, meetings, and conferences, including the workers. This huge population needs to inhale and exhale good quality air for reasons of health and comfort of the users. While architectural design makes provision for adequate ventilation either through natural and/or mechanical means, most time the effect of this is negated by the offshoot of users estimated population. This in most instances is exceeded by the attendees causing overcrowding and poor indoor air quality [10]. In addition, the presence of tobacco smoke within the environment, radon, nitrogen oxide (No2), and aldehyde also contaminate the indoor air [11]. Consequently, these cause health symptoms such as headache, fatigue, breathing difficulty (asthma) and irritated skin, and low work/users' productivity which has become a serious concern in the last three decades [12].
In Nigeria, the majority of commercial buildings, particularly, event centers utilise motorized airing schemes as airing and air-conditioning to sustain the building inside cooling because of the hot weather. While mechanical systems provide fresh air in good condition, however, when faulty, they convey polluted air to indoor environment [8]. Consequently, the contaminated air by the mechanical systems affects workers' health and psychology due to the poor IAQ that causes illness to the building users and invariably, limit their productivity [13].
Besides, polluted ambience does not allow indoor air temperature to be controlled, either too hot or too cold, which makes the occupants of the buildings uncomfortable [14].
This research seeks to explore the effects of air pollution on the indoor air quality in commercial buildings such as event centres in Kogi State, Nigeria. It is anticipated that government could formulate policies for improving indoor air quality performance in commercial building designs, resulting in a comfortable experience for users and workers' productivity.

Pollutants and Health Impacts
Manisalidis, Stavropoulou, Stavropoulos and Bezirtzoglou [15] explained pollution as the release of toxic compounds into the environment which endangers humans and other living beings. The compounds could be toxic solids, liquids, or gases created in greater quantities than ordinary attention that degrade the attribute of the human environment and are discharged in huge amounts into the air making it dangerous to human health [16]. Anthropogenic air contamination is one of the utmost grave civic fitness risks worldwide, responsible for about 9 million deaths annually [17]. Through the advancement of livelihood ideals, extra man-made supplies and chemicals are being employed in manufacturing. Insect killer, clean-up chemicals, air fresheners, and culinary gases are further contributors of inside air contamination [18].
Building materials and furnishings frequently release dangerous air pollutants, such as various forms of Volatile Organic Compounds (VOCs), which have serious consequences for human health. Human lifestyle and everyday activities (such as cooking, washing, and cleaning) are the primary causes of an increase in pollution levels within a structure [19]. Indoor pollution is most influenced in buildings with insufficient ventilation, a need of air cooling schemes, individual behaviours, and a diversity of materials, chemicals, and gases [20]. Giani, Castruccio, Anav, Howard, Hu and Crippa [21] espoused that inside air contamination begot over 1.5 million deaths in the year 2000. Table 1 lists several contaminants found in indoor environments as well as their health consequences. The critical elements that influence the variety and composition of indoor air pollutants, as well as human health, are poorly known [2]. Source: [2,22] Wolkoff [23] affirmed that how buildings are designed affects its indoor surroundings and consequently affects building users' health. Hence, poor indoor air quality can result a variety of health problems, including headaches, dizziness, and nausea, as well as asthma, cardiovascular disease, cancer, and mortality [22] . The harshness of a contaminant's influence on human fitness is resolved on its concentration and length of exposure [24]. Furthermore, the impurity's influence is also affected by the age and gender of those inhabiting a location [25,26].
Air pollution causes a range of adverse physical condition. Even when there is little ambiance pollution, the fitness of susceptible and perceptive persons might be debilitated [27]. Interim exposure to air contamination has been linked toward Chronic Obstructive Pulmonary Illness (COPI)), cold, asthmatic, panting, respiratory illness, including a high risk of hospitalization (a measurement of morbidity), according to [28]. Grave asthma, pneumonic deficiency, and coronary disease, including its death are entirely lasting effects of ambiance contamination. In addition, air contamination seems to contain a variety of adverse fitness effects in untimely person existence, plus pulmonary, cardiac arrest, mental, including postnatal matters [29]. These effects can lead to baby fatality or grave illness in maturity age [30]. According to WHO national reports, there is an elevated risk of morbidity and death [24,31].
Work Exposure Limits (WELs) may apply to healthy working-age adults (20-59) who are directly exposed to pollutants as part of their job [15,32]. However, provision room is often made for lower exposure limits [3]. These lower limits should be implemented if a person is exposed to pollutants for a period of time that exceeds 8 hours or if their occupational activity does not directly involve the pollutants [33]. To understand the complexities of the challenges, it is necessary to investigate the building bio-network which integrates building design, indoor pollutants, and human health. Previous research by Aye [34] demonstrated that poor indoor air quality in business buildings has an effect on human well-being and working effectiveness.
However, the critical factors responsible for the poor indoor air quality in buildings are limited in knowledge.
Yahaya, Hagos and Basrawi [1], research on indoor air quality in commercial buildings in Kautan unveiled that while some buildings have acceptable interior air quality, others have limited air movement, a lot of dust, and high temperatures. Abdullah [11], further the understanding on indoor air quality in Malaysian office buildings and analyzed public health issues about job performance and productivity. The study found that the building's indoor air quality was adequate and suitable for habitation despite the presence of countable symptoms of sick building syndrome (SBS) among its residents. Yet, little is known on the implications of IAQ in commercial buildings on its users. Hence, more study is required on IAQ in impoverished nations such as Nigeria with particular attention to elucidate building users on the acceptable exposure to pollutant levels and its implications to their health. As such, there is the need for research to examine the IAQ in business buildings for public health purposes because of its association to workers and customers' performance and productivity.
The study by Yadav [4]  been attributed to poor indoor air quality [22]. The health, reaction, and workability of users are affected by indoor environmental factors, particularly temperature and air quality. According to Rowan [38] the efficiency of air movement, the labour circumstances of places, and the building appearance and silhouette all have an impact on indoor air quality. The sources of contaminants in indoor and outdoor areas are important to investigate since they are all relevant to the monitoring of indoor air impurities.
The coronavirus, known as the COVID-19 pandemic, which produces negative health effects, is aided greatly by poor air quality produced by ineffective aeration [39]. As a result, indoor air quality remains a critical issue, affecting occupiers' health, pleasure, and production. As a result, the attribute of inside air have been a critical factor in assessing the performance of different buildings, and it may be measured by the assimilation of several air impurities in the inside environment [40]. Air attribute is harmed by inappropriate ventilation, insufficient filtering, and diffusion of air in small areas, although it can be improved by regulating the source, constructing correct air movement schemes, and using air cleansing [35].
Indoor air quality has an impact on people's morale, which can lead to users' complaints and decreased productivity among employees and workers. The productivity of the building is vital to the completion of its tasks and responsibilities (function). According to Burroughs and Hansen [3], because people expend a lot time inside buildings, the attribute of inside air and thermal coziness have turn into exceedingly important to investigate. For instance, if the use of an event center decreases due to poor interior air quality, it will not serve its full role, resulting in low productivity. According to Domínguez-Amarillo, Fernández-Agüera, Cesteros-García and González-Lezcano [30], indoor environments contain a significant influence on person fitness, comprising allergic reactions, flu, respiratory illness, migraines, and productivity. Indoor air pollution, due to dangerous chemicals and other harmful compounds, has a decuple detrimental consequence on person life attribute when contrasted to contaminated air exterior [1]. All of these health consequences of poor indoor air quality demand the necessity for this study with the goal for professionals to address the issues by design.

Methodology
The study employed descriptive research design using a quantitative research approach.  Table 2 shows the participants' response rates. It revealed that 120 surveys were disseminated to 103 participants that were concluded and the feedback was analysed. The received survey signified 85.8% (i.e., 103 respondents) of the reply value and was reasoned sufficient for the inquiry to be assessed as espoused by Morse [42]. A reliability test to determine the interior trustworthiness of participants through the components on a multiple-item measure was employed for this study as opined by [43]. The result obtained indicated that the results were suitable by a trustworthiness of 0.616 that suggests the responses are dependable and satisfactory (see Table 3).   [44] which found that females are more in hospitals and event centers than males. This suggests that there is the need to ensure good quality indoor air in event centers as females are more susceptible to air bone infection than males. The results revealed that the majority (69.6%) of the respondents in the two buildings are in the age range of 15-29 years old, while the lowest (5.9%) age ranges from 45-59 years. This insinuates that youths was graded the foremost in event attending as adults' turnout is really small. This suggests that youth (age spectrum) are the active majority and are appropriate age for labour and social activities. Although the number of older people is little, it is significant to be careful of the inside ambiance attribute of the structure as the opposition echelon of the older people is higher than that of the younger people.

Results and Discussion
The respondents were asked about their experiences with indoor air quality in the event centers.
This assessment ranges from very comfortable (5) to not comfortable (1). The outcome of the analysis is revealed in table 5. The findings shows that 57.3% are in the comfy precinct, 35% are moderately cozy, and 7.8% are uncomfortable with the occasion centers studied. This indicates that the generality of the participants have a good echelon of contentment with being comfortable with the indoor air quality at the selected event centers.
Questions were asked about what makes the indoor air quality uncomfortable for the users relative to its contributing factors shows that small window size, small door size, and absence of air conditioners (AC) were causative factors as they were found to positively correlate to the high temperature in the indoor but negatively correlate to its being moist (see Table 6). Though, it was a small space in relation to the amount of customers, and the unlikable smell was unhelpfully linked with the fact that it was hot. This connotes that the majority of the participants articulated that the main elements begetting uneasiness to users due to the poor quality of indoor air at the event centres are the hotness of the air and having small window sizes, small door sizes, and the absence of air conditioners as its causative factor to design. This finding corroborates the result of the study by Yahaya, Hagos and Basrawi [1] that high temperatures lead to very hot environments, which can cause discomfort to building occupants such as headaches, dizziness, and fatigue. To prevent high temperatures, there should be adequate fenestrations and/or working air conditioning system in the building.
Also, the findings from this study show that sufficient quantity of entrances, number of ambiance conditioners plus room magnitude comparative to the number of customers all contribute significantly to the elements influencing good inside air attribute. This suggests that sufficient openings, suitable air conditioners, and a large crowd relative to space size affect the quality of indoor air quality in event centers. This result substantiates the findings of Rosbach [45] and Sekhar [46] that thermal comfort is related to ventilation adequacy and thermal comfort is crowdedness in indoor environments such as schools and event centers. Consequently, sufficient ventilation is required to reinstate musty indoor air with fresher air. Table 7 shows that the majority (75.5%) of the responders robustly agrees that the frame of mind of business center clients is effected via the attribute of the inside ambiance, though, 11.7% differed. This implies that the mental state of the people using the building affects the indoor air quality.

Source: Author's Field work, 2021
Also, the majority (66.7%) of the participants agreed that the attention span of occasion center customers is clouted via the attribute of the inside ambiance, although, 13.7% dissented. This implies that the customers' concentration duration in the business centre depends on the quality of the inside air. Furthermore, the majority (69.6%) of the participants concurred that the interests of commercial center customers are affected through the quality of inside air, while 12.7% differed. This suggests that indoor air quality affects workplace performance and productivity based on the mood, concentration, and interest of the users. Further findings indicated that majority of the respondents strongly agreed that the fitness of the customers' in the business center is impaired by inside ambiance attribute. However, 20% were neutral that the health of event center users was affected by indoor air quality. This result corroborates the findings of Toyinbo et al. (2019) that occupants' vulnerability to contaminants could contain diverse affect on their fitness, prospectively catalyzing infirmity, nonattendance, and reduced production. Accordingly, 69% of the participants robustly agreed that inside ambiance attribute is a significant element of occasion undertakings while 18% disagreed. This suggests that the majority (87%) of the participants concurred that inside ambiance attribute is an important factor that influences the efficiency of the activities of the users in the event centers. This corroborates the previous findings by Abdullah [11] that indoor ambiance attribute impacts on the workplace effecting and productivity of commercial buildings.

Conclusions
This study examines the implications of air pollution on the inside ambiance attribute in business buildings such as event centers in Kogi State, Nigeria. Findings in this study demonstrate that sufficient quantity of entrance, suitable air conditioners including sufficient room volume comparative to the number of customers contribute to an enormous degree of the components poignant to the good inside ambiance attribute in event centers. Workforce performance and productivity were negatively affected based on the mood, concentration, and interest of the users. This affects the efficiency of users' activities at the event centers. As a result, event centers should be designed with enough openings in terms of size and number for optimum ventilation. In order to provide thermal comfort in event centers, there is need to integrate passive and mechanical cooling within the scheme. Furthermore, to evade overcrowding, business buildings should be designed with room size proportional to the projected number of users. Toxic materials should be avoided in the building, and air conditioners should be constantly maintained as the need arises on a regular basis.