Review
Health effects from low-frequency noise and infrasound in the general population: Is it time to listen? A systematic review of observational studies
Graphical abstract
Introduction
Unlike several other environmental stressors, noise pollution, especially in the urban environment, is still increasing (Öhrström et al., 2006, World Health Organization (WHO), 2011). Well-documented evidence supports an association between higher levels of environmental noise and various adverse health effects, such as cardiovascular diseases (Münzel et al., 2014), sleep quality (de Kluizenaar et al., 2009, Omlin et al., 2011, van Kamp and Davies, 2013), annoyance (Miedema and Oudshoorn, 2001, van Kamp et al., 2004, Frei et al., 2014) and also cognitive development and hyperactivity in vulnerable population groups such as children (van Kamp and Davies, 2013, Basner et al., 2014).
Noise ranks among the environmental stressors with the highest public health impact (WHO, 2011) and it is therefore important to regularly monitor for the determination and comprehension of possible effects on health. An underinvestigated noise component in relation to health effects is low frequency noise (LFN) (sound below 250 Hz), including infrasound (up to 20 Hz) (Berglund et al., 1996, Leventhall, 2004). Although LFN is audible at sufficiently high pressure levels (decibels, dB), it can also occur below the human hearing threshold (Leventhall, 2007), considering that the human ear responds better to sound frequencies between 500 Hz and 8 kHz (Farina, 2014).
Sounds within the low-frequency sound spectrum comprise a common, everyday-life environmental exposure, produced by natural (sea waves, wind turbulence) as well as by man-made sources (industrial installations, domestic appliances, transportation) sources. The latter constitute the primary cause of LFN (Berglund et al., 1996), while the rapid expansion of infrastructure has increased the attribution of symptoms to LFN and public concern (Jakobsen, 2012). According to earlier evidence from local environmental health authorities, complaints due to LFN comprise about 35% of the total noise complaints filed (Bengtsson and Waye, 2003). Low frequency noise in the residential environment is described as a constant, deep and humming/rumbling sound and although complainants perceive it with their ears, the perception of bodily or external vibration is also possible (Møller and Lydolf, 2003). Annoyance is usually the first reaction to this type of noise, often accompanied by secondary effects, such as headache, concentration difficulties palpitations and sleep problems (Møller and Lydolf, 2003, Leventhall, 2009).
A number of studies suggest an association between LFN and various physiological and psychological reactions such as annoyance, hearing threshold shift, concentration problems, lower sleep quality, mood effects (Persson Waye et al., 1997, Ising and Ising, 2002, Leventhall, 2004, Pawlaczyk-Łuszczyńska et al., 2005) and also controversial conditions such as the so-called vibro-acoustic disease (Alves-Pereira and Branco, 2007, Chapman and St George, 2013). Additionally, adverse health effects from occupational exposure have been observed on memory, annoyance and performance (Gomes et al., 1999, Persson Waye et al., 2001, Bengtsson et al., 2004, Kaczmarska and Łuczak, 2007, Pawlaczyk-Luszczynska et al., 2009). Evidence on vascular and respiratory effects is inconclusive (Schust, 2004).
Although the potential impact of LFN as environmental pollutant has been highlighted by the WHO (Berglund et al., 1999), current evidence is mainly based on case studies and laboratory experiments of small sample sizes and short exposure sessions (Leventhall, 2009, Ambrose et al., 2012). It is therefore unknown to what extent such health effects occur in relation to everyday-life exposure to LFN at the population level. Observational studies are highly important due to the investigation of everyday-life exposure and effects in larger samples.
No systematic evaluation of the peer-reviewed observational epidemiological literature has been performed up to date on the association between LFN and health. The present paper aims to fill this gap in the literature.
Section snippets
Data sources and search
Pubmed, Embase and PsycInfo were searched as primary databases for relevant studies published between January 1st, 2000 and January 30th, 2015. There was no a-priori language restriction.
A wide range of (combined) keywords was used, related to environmental noise exposure and health effects, presented in Table 1. In addition to the electronic database searches, the reference sections of previous systematic reviews and key papers were examined. The databases of the following relevant journals
Literature search and study characteristics
Fig. 1 illustrates the literature search process. We examined 4014 citations in total and based on our criteria we identified 7 observational studies on the association between everyday life exposure to LFN and health effects (Table 2). All studies were of cross-sectional design and most of them were conducted in Europe (n = 4).
Response rates were reported in 6 studies, ranging from 71% to 93%. Noise sources of primary concern in the investigation were ventilation systems, neighborhood/road
Primary findings
This systematic review identified the observational epidemiological studies undertaken the past fifteen years on the association between everyday life LFN, including infrasound, and health effects in the general population. A descriptive meta-analysis was carried out as a first effort to estimate the pooled prevalence of high annoyance attributed to LFN at the level of the adult population living in the vicinity of some source of LFN. The review showed some associations between exposure to LFN
Conclusions
Evidence from the present systematic evaluation of observational studies suggests an association between exposure to LFN components and self-reports of annoyance and various symptoms in the population. However, results should be interpreted with caution due to the small number of existing studies. An association with other health effects might exist, but evidence is still limited and inconclusive. More epidemiological research is imperative, involving larger samples and better methodological
Conflict of interest
None declared.
Acknowledgements
The present paper was written within the framework of the updated LFN guidelines of the Dutch Municipal Health Services. The authors would like to thank Annelike Dusseldorp, Rita Slob and our colleagues at NIVEL for their feedback on the paper, especially Tessa Magnée and Dolf de Boer.
References (51)
- et al.
Vibroacoustic disease: biological effects of infrasound and low-frequency noise explained by mechanotransduction cellular signalling
Prog. Biophys. Mol. Biol.
(2007) - et al.
Low frequency noise impact from road traffic according to different noise prediction methods
Sci. Total Environ.
(2015) - et al.
Non-specific physical symptoms and electromagnetic field exposure in the general population: can we get more specific? A systematic review
Environ. Int.
(2012) - et al.
Actual and perceived exposure to electromagnetic fields and non-specific physical symptoms: an epidemiological study based on self-reported data and electronic medical records
Int. J. Hyg. Environ. Health
(2015) - et al.
Auditory and non-auditory effects of noise on health
Lancet
(2014) - et al.
Evaluations of effects due to low-frequency noise in a low demanding work situation
J. Sound Vib.
(2004) - et al.
How the factoid of wind turbines causing ‘vibroacoustic disease’ came to be ‘irrefutably demonstrated’
Aust. N. Z. J. Public Health
(2013) - et al.
Meta-analysis in clinical trials
Control. Clin. Trials
(1986) - et al.
Effect of nocturnal road traffic noise exposure and annoyance on objective and subjective sleep quality
Int. J. Hyg. Environ. Health
(2014) - et al.
Bias and causal associations in observational research
The Lancet
(2002)