Noise comprises a single or mixture of sound waves of different sound levels that are produced by single or multiple sources [1]. Noise is usually described in terms of loudness (intensity) and pitch (frequency) and noise exposure is measured using a logarithmic decibel (dB) scale [2]. The threshold limit for tolerable noise is 45-65 dB [3,4]. Sound above 120 dB will cause pain to the ear [4]. Noise pollution is an audible unwanted sound that poses a threat to a person’s health and well-being. It is environmental problem that increases very rapidly as a result of improvement in commercial, industrial and social activities ((Environment Protection Authority (EPA) 2011). Sources of noise are industrial and commercial activities, including operations of factories and workshops, transport activities, constructions activities and social activities in urban settlements, including market places, sports events and entertainments (Environmental Operations Unit, Northern Territory Environment Protection Authority, 2011). In residential areas, noise can be very distracting, and the type of noise in this environment is referred to as the neighborhood noise. Neighborhood noise consists of a range of individual households and family activities that generate noise that are audible further than and beyond the confines of the household [5]. Sources of neighborhood include noises from domestic pets, transport and domestic repairs and construction activities, religious activities and civil disruptions (Environmental Operations Unit, Northern Territory Environment Protection Authority 2011).

Studies have shown that noise above the tolerance limits can be associated with rising incidence of deafness among urban dwellers. The World Health Organization (1999, 2011) and other studies have linked noise pollution to hearing impairment, speech intelligibility, physiological dysfunction, mental illness, performance reduction, and cardiovascular diseases [2]. In India (Delhi and Calcutta), Singh and Mahajan [6] showed that the general level of urban noise was between 60 and 95 dB (higher than the tolerance level). Murli and Murthy [7] showed that transportation was the major cause of noise pollution in major parts of India, and these exhibited temporal variation (it is more intense in the morning and evening ‘rush-hours’). In Europe, more than 90 million people suffer from unacceptable noise levels, and this necessitated the inauguration of the Environmental Noise Directive (END), 2002/49/EC for the region (European Commission News, 2005). Following a proposal by the commission adopted in 2000(1), the European Parliament and Council adopted END with the aims of defining a common approach intended to avoid, prevent or reduce on a prioritized basis the harmful effects, including annoyance, due to the exposure to environmental noise. Generally, in cities, noise is considered to be the third most hazardous type of pollution, right after air and water [8].

In many developing countries, including Nigeria, noise pollution is a typical attribute, probably because of poor awareness and poor public education [4]. Causes of noise pollution in Nigeria include transport activities such as automobiles, commercial motorcycles, recording houses, use of electricity generators, and religious activities [9]. Oyedepo and Saadu [10] in a typical Nigerian urban environment (Ilorin) linked urban and population growth to noise pollution. They also noted that litigations are few and legal provisions are either unknown to guide Nigerian residents on noise pollution. In addition, very few studies have been carried out on noise pollution in Nigeria.

Noise is increasingly becoming a norm for the Nigerian environment, and this is typical of most developing countries. While noise pollution is also a problem of many developed countries, the concerns for this source of pollution are very limited for most countries in the developing regions. In Nigeria, little or no concern has been raised for noise pollution, and only very few study are also available in this regards [11]. On the other hand, existing studies have described noise as a slow and subtle killer through its hazardous effects on humans [12,13].

The town Ile-Ife is an example of a typical Nigerian town with reference to household characteristic and environmental problems. Since noise pollution is rapidly increasing with improvement in technology and growth of urban centers, no standard measures have been taken in the study area to effectively control noise and its effect. Thus, there is the need for understanding the sources, effect and coping strategies of neighborhood noise pollution as well as the perception of individuals in the noise polluted areas, as this can play an important role in environmental improvement at the local level. Also, it can be instrumental in helping government officials and others determine what needs to be done to combat environmental problems at the domestic level. Furthermore, this study will contribute to the development of the town and most importantly to the academic knowledge. The aim of this study is to identify and assess the impact of noise pollution in the neighborhood of Ile-Ife. Specific objectives are to examine the sources of noise, and residents’ perception on effects and coping strategies of noise pollution.

Study area

Ile-Ife, Osun State covers an area of approximately 350 square kilometers and lies between Latitudes 7°28’N and 7°34’N of the Equator, and Longitudes 4°30’ E and 4°31’E of the Greenwich meridian (Figure 1). The town lies at the intersection of roads from Ibadan, Ilesha, and Ondo. According to 2006 population census, Ile-Ife has an estimated population of 355,341 inhabitants [14]. Ile-Ife is home to Obafemi Awolowo University and other industries in Ife including palm processing, sawmilling, trading, local arts, lumbering and many other important places like University Teaching Hospital Complex, Ife Museum of Antiquities, Opa Oranmiyan, Okemogun Shrine, Oduduwa Palace, Zoological Gardens and Odua Shrine.

Figure 1: Ile-Ife Town in Nigeria. The insect map shows the location of Ile-Ife in Southern Nigeria.

The climate of the study area is of the humid subtropical type (Koppen climate classification). The climate is controlled by the major air masses: the tropical maritime air mass (Mt) and the tropical continental air mass (cT). The tropical maritime blows between March and October and brings the rainy season, the tropical continental air mass blows between November and February and brings the dry and harmattan seasons. Ile-Ife has a mean annual temperature of about 28°C and mean annual rainfall of between 1,200 and 1,500 mm, which can rise to above 1,800 mm during some very rainy years. The monthly rainfall pattern is bimodal, with peaks in July and September/ October. The dry season occurs between November and March. Relative humidity varies between 75.8 and 86% [15].

Data types and sources

Both primary and secondary sources of data were used for this study. The primary data were a set of close ended questionnaire that was administered to residents. The structure of the questionnaire is such that seeks to generate information on variables such as socio-economic characteristics, neighborhood noise awareness and sources, impact of neighborhood noise on other activities, the effect of noise and the coping strategies. Secondary data was a 1:25,000 land use map from the Ife Central LGA Town Planning Office, from which sampling areas were delineated.

Sixty copies of questionnaire were distributed in three purposively selected areas of Ile-Ife. The areas include Sabo, representing commercial area; OAU, representing institutional area; and Ede road, representing a typified medium-low residential area. Sample population which were randomly selected consisted of students, civil servants, academics, artisans, business men and women, all who are 18 years and above because they are considered to be conscious of noise effect. Eighty (80) copies of questionnaire were distributed, only. The 1:25,000 scale land use map of Ile-Ife served as the basis for which the sampled areas were delineated.

Data analysis

Responses of residents to questionnaire from the different areas (Table 1) were coded into a statistical software package (Statistical Package for Social Sciences, SPSS version 17). Responses were analyzed using simple frequency percentage distribution to examine perception across the various land uses. Perceptions were also scored and ranked based on the percentage agreement on any issue by residents.

Table 1: Sampling areas and the quantity of questionnaire administered.

Socio- economic and demographic characteristics of selected residents in Ile-Ife

Table 2 shows the demographic and socio-economic status of the respondents used for the study. 53.3% of the respondents were male and 46.7% were female. Majority of the respondents, 75%, aged between 18 and 30 years while 25% are above 30 years of age. About 73.3% of the respondents are single while 26.7% are married or living together. 78.3% of the total respondents had tertiary education, 20% had secondary school education, while only 1.7% of the respondents had primary education. 39.7% of the total respondents are employed while 59.3% are either unemployed or studying. The income group distribution shows that majority of the respondents, 46.7%, earn below N18, 000, while only 20% earn above N50, 000, 87.5% of the respondents had resided in their location for less than 10 years.

Table 2: Socio-economic and demographic characteristics of selected residents.

Perception of residents on sources of noise pollution in selected areas

This section explains the various activities that generate neighborhood noise in the sampled areas. Table 3 shows that in the lowmedium residential areas, domestic pets (55%) and religious activities (55%), are the major sources of noise thereby generated the highest level of noise. In the institutional environment and in the commercial/ high density residential areas, transportation (95% and 100% respectively), is the major source of noise and therefore generated the highest level of noise.

Table 3: Sources of noise pollution in selected sample areas in Ile-Ife.

Awareness of neighborhood noise

Table 4 shows that, 70% of those in low-medium density areas view neighborhood noise as a problem and 65% are annoyed by it. In the institutional environment, 90% see noise as a problem and 85% are annoyed by it, while in commercial/ high density areas, 85% see noise as a problem and are also annoyed by it. In the low-medium density areas, the major cause of annoyance is civil disruption (80%) and domestic repairs (57.3%), while in the institutional environment the major cause of annoyance is transport (95%) and construction activities (94.4%). In the commercial/high density area, the major cause of annoyance is transportation (77.8%) and civil disruption (66.6%).

Table 4: Perception on the awareness of neighborhood noise.

Effect of neighborhood noise pollution

About 55% of those in the low-medium density areas agree that noise interferes with their daily activities, 80% of those in the institutional environment agrees that noise interferes with their daily activities, while 60% in the commercial/high density areas agree that noise interferes with their daily activities. Table 4 illustrates that in all three land uses- low-medium, institutional and commercial/high density areas, noise interferes with relaxation (100%). In the low-medium density areas, noise also interferes with studies (100%) and sleep (90%), in the institutional environment, noise interferes with studies (100%) and hearing (94.8%), while in the commercial/high density areas, noise also interferes with sleep (100%) and studies (83.3%) (Table 5).

Table 5: Perception on the effect of neighborhood noise.

Adaptation/Coping strategies

Table 6 shows the various coping strategies of residents in the three land uses. Those who just cope /adapt to the noise in the low-medium, institutional environment and commercial/high density areas are 40%, 25% and 50% respectively.

Table 6: Adaptation Strategies of Residents.

This study aimed at identifying and assessing the impact of neighborhood noise pollution in Ile-Ife, Osun State. Major sources of noise pollution in Ile-Ife vary with the different land uses. The major sources of noise are domestic pet and religious activities (both 55%) in the low-medium residential area, transportation (95%) and religious activities (60%) in the institutional environment and transportation (100%) as well as construction activities and civil disruption (both 75%) in the commercial/high density areas. These sources of noise pollution are in line with the sources of similar studies. In terms of the awareness of neighborhood noise in Ile-Ife, more than 50% of the residents view neighborhood noise as a problem and are annoyed by it. This indicates that the residents of Ile-Ife are very much aware of noise. The study also shows the effects of neighborhood noise pollution as seen in the above results. Over 50% of the residents of Ile-Ife agree that noise interferes with their daily activities especially relaxation and the use of GSM. Other activities with which neighborhood noise interferes are hearing, speech, listening to radio, studies, watching T.V, sleep, in door conversation and task performance. This result is similar to studies that showed that noise can disturb people’s rest, sleep, work and communication and it can damage hearing and manifest psychological, physiological and possible pathological reactions. Studies in Indian also showed that noise pollution was responsible for the rising cases of deafness of many people especially in Delhi and Calcutta [5].

This study has also shown that though the residents of Ile-Ife are aware of noise and its effects, they do not adopt appropriate coping strategies to noise pollution. Majority of the residents just cope with or adapt to the noise while others move away, ignore, close the windows or do not cope at all with the noise. Some residents cope with the noise by turning on their television, radio or music players to distract their attention from the noise. However in contradiction to the above result, coping strategies in noise polluted areas includes the use of heavy fabrics and curtains with sound-absorbing technology. Changing windows by replacing single pane with double-pane is also another coping strategy (Northern Territory Environment Protection Authority, 2011). Sound absorbing materials, drapes, curtains and carpets which deaden noise, quieter air-conditioners, ventilators and other household appliances, sound-insulated ceilings, walls, doors and windows all help to reduce unwanted noise.