The question of whether environmental noise exposure causes mental ill-health is still largely unanswered. This paper reviews the studies of environmental and industrial noise and mental ill-health published between 1993 and 1998 and suggests possibilities for future research. Recent community based studies suggest high levels of environmental noise are associated with mental health symptoms such as depression and anxiety but not with impaired psychological functioning. Several studies find that self-reported noise sensitivity does not interact with noise exposure to lead to increased vulnerability to mental ill-health. Chronic aircraft noise exposure in children impairs quality of life but does not lead to depression or anxiety. Further research on environmental noise and mental health should be accompanied by more accurate and detailed measurement of noise exposure and consideration of the impact of other environmental stressors and careful measurement of confounding factors such as social class. Target study populations exposed to noise should be chosen to avoid those where noise exposure is likely to have led to noise sensitive individuals moving away from the area. There should also be greater use of standardised instruments to measure a wider range of mental health outcomes. Also other physiological outcomes such as hormonal measures could with benefit be measured simultaneously.

Compared to other environmental issues, only a limited number of epidemiological studies is available on the relationship between traffic noise and cardiovascular diseases. The available literature provides no epidemiological evidence of a relationship between noise exposure and mean blood pressure readings in adults. However, noise-related increases in blood pressure are consistently seen in children. As far as hypertension as a clinical outcome is concerned, there is little evidence that exposure to high traffic noise levels is associated with an increased risk. With regard to ischaemic heart disease there is some evidence in the literature of an increased risk in subjects who live in noisy areas with outdoor noise levels of greater than 65-70 dBA.

Noise exposure in both residential and occupational settings produces a range of auditory and nonauditory health problems. Efforts of the relevant authorities to reduce these effects may be supplemented by the adoption of various self-protective behaviours by individuals. Unfortunately campaigns designed to encourage such self-protective behaviours are likely to meet with limited success. The present paper considers the shortcomings of such campaigns and offers prescriptions for improving them. Campaigns based on these prescriptions and on thorough research of the factors involved in health promotion generally, as well as those particular to each case, should significantly advance efforts toward individuals protecting themselves against the ill effects of noise exposure.

The aim of this study is to investigate how students rate the annoyance and effects of noise in their working environment. 216 students, between the ages 13-15 years, and 12 teachers took part in this study. Sound level measurements were made for 20 minutes in the middle of a lesson for each class. On the measurement occasion the students were seated in a class room working on mathematics. Immediately after the sound level measurement, the students and the teachers filled in a questionnaire. The correlation between sound level and perceived annoyance and rated effect of noise on the students´ schoolwork was poor. The correlation between the annoyance and rated effect of noise on the students´ schoolwork was significant. Equivalent sound levels during mathematics lessons were 58-69 dB(A). Even though the sound levels were relatively high the students claimed that they were just moderately annoyed. More than 1/3 of the students claimed that the existing sound environment obstructed their work. No difference was found between boys and girls in rated annoyance and rated effect on their work. The younger students were more annoyed than the older ones. The participants claimed that chatter in the class room and scraping sounds from tables and chairs were the most annoying sound sources. The teachers shared this opinion. The concurrency between the students´ rating of their annoyance and the teachers´ rating of the students annoyance was remarkably low.

Noise exposure is the most common cause of tinnitus. Noise induced permanent tinnitus (NIPT) can derive from occupational noise exposure, leisure noise or acoustic trauma. In gen­eral NIPT is high - pitched and tonal. The most common observed frequency of tinnitus on pitch matching is the same as the worst frequency for hearing. The sensation level of NIPT is usually low and sometimes negative. There is no correlation of significance between the dis­comfort caused by NIPT and audiometric findings. In occupational NIPT the interval between the start of noisy work and the appearance of tinnitus is long (many years) but with leisure noise and acoustic trauma the interval between exposure and tinnitus is frequently very short (immediate). It is a problem that the incidence of musically induced tinnitus is increasingly more common. It is also a much greater handicap for a young individual to suffer from tinni­tus than from a small high tone hearing loss. Much more attention needs to be given to improve these matters. The treatment of NIPT is not different from tinnitus treatment in general.

Noise measurements were made in cinemas during the showing of four films, to establish whether the noise levels from films might pose a risk of damage to hearing. The L _Aeq levels for the full playing time of each film were all below 80 dB(A). Noise levels did sometimes exceed 90 dB(A) but this was never for more than a total of two minutes, and was usually for only a few seconds. Repeat L _Aeq levels for the same films were shown to vary by 3-4 dB across different cinemas. Based on this limited sample of films and cinemas, there is no evidence that sound levels in cinemas cause permanent damage to hearing.

We have analysed the association of noise-induced hearing loss with various risk factors among 685 workers in forest, shipyard, and paper mills. Occupational histories, health, environmental factors, and noise exposures of each worker were retrieved from the database of NoiseScan, our expert program on hearing. The mean hearing level at 4 kHz was 21.5 dB ± 20.3 dB HL. It correlated significantly with age, noise emission level and noise exposure level. However, these factors could only explain about 2 dB HL of the variation in hearing level. Impulse noise in the shipyard work caused increase in hearing level of 12 dB HL at 4 kHz when compared to steady state noise exposure of forest work. Hearing level correlated with serum cholesterol levels, use of analgesics, blood pressure and smoking. An elevated cholesterol level increased hearing loss in both the high- and low-exposure groups. The use of analgesics did not increase a permanent threshold shift in the low-exposure group, but did in the high-exposure group. Systolic blood pressure, smoking, cholesterol level and the use of painkillers explained 36 % of the variation in hearing level at 4 kHz, whereas noise exposure alone explained 25 % of the corresponding variation.

Field studies and laboratory experiments on noise-induced sleep disturbance show conflicting results and do not provide sufficient knowledge for valid exposure-effect relationships. It is also well known that habituation exists for awakenings whereas other effects such as heart rate reactions and minor EEG-reactions do not habituate. In this paper comparisons are made between findings from a series of laboratory and field studies on effects of road traffic noise on sleep performed by this athor. Possible reasons for the discrepancies found in various studies in laboratory and field are commented on and methods and research needs are discussed. Comparison of results obtained in research on perceived sleep quality parameters at this Department that used the same methods in laboratory and field studies showed fairly good agreement for difficulties in falling asleep and perceived sleep quality whereas awakening reactions were much less frequently reported in the field studies.