VIII. Medical effects of aircraft noise: Review and literature

Summary The results of the available epidemiological studies on medical effects of aircraft noise are combined and discussed. It appears that the results support each other. The conclusion is drawn that aircraft noise, as prevalent around many airports, constitutes a very serious threat to public health in all its aspects: affection of well-being, mental disorders, somatic symptoms and diseases (especially cardiovascular diseases). A recommendation is given for the protection of the population in the vicinity of airports: the aircraft noise should not exceed NNI = 20.     

机场工作环境噪声对心血管疾病危险因素的影响

目的研究机场工作环境噪声、个体对噪声的烦恼性对心血管疾病危险因素的影响,探讨噪声对心血管疾病的影响机制。方法采用横断面研究方法,调查广州飞机维修工程有限公司工作人员的一般情况、噪声接触水平以及血脂、血压等生理生化指标。采用协方差分析等方法分析噪声接触水平、个体对噪声的烦恼性与心血管疾病危险因素之间的关系。结果在校正年龄、体重指数、吸烟、饮酒、家族史等因素后,发现工作环境噪声水平<50dB(A)、70～85dB(A)和>85dB(A)组调查对象的舒张压(DBP)分别为74.52、75.45和76.35mmHg,动脉粥样硬化指数(AI)分别为4.55、4.80和4.97,其差异有显著性(P<0.05)。进一步分析揭示噪声和烦恼性的交互作用对高密度脂蛋白胆固醇、收缩压、空腹血糖的影响具有统计学意义。结论机场工作环境噪声、个体对噪声的烦恼性与心血管疾病危险因素存在不同程度的相关及交互作用。     

Impairing effects of noise in high and low noise sensitive persons working on different mental tasks

Objective  There is no information of mental strain in noise sensitive persons working under moderate levels of noise. The aim of the study was to determine relevant dimensions of impairing effects differentiating between noise sensitive and insensitive persons. Methods  56 participants (27 men, 29 women; 18–31 years old) were classified into 28 low and 28 high noise sensitive persons. They worked either on a grammatical reasoning task (GRT) or a mental arithmetic task (MPT) under realistic road traffic scenarios [LAeq 55 dB(A)]. Afterwards they rated their annoyance and subjective mental strain. Results  A multivariate analysis of variance provided significant effects for the individual noise sensitivity (P < 0.01) and the kind of task being performed (P < 0.01). To determine to what extent the rating scales lead to a differentiation of the four groups, a 2-factorial discriminant analysis was carried out subsequently. Results showed, that psycho-physiological effort and emotional strain differentiated best between the noise sensitivity groups and psycho physiological effort and focus on tasks (attention) separated the tasks. Conclusion  Noise sensitive persons are more distracted by noise than insensitive persons. Furthermore the results suggest that noise sensitive subjects do not only evaluate a noisy situation as more annoying but experience higher levels of strain than insensitive persons.     

From chemosensory thresholds to whole body exposures—experimental approaches evaluating chemosensory effects of chemicals

Objectives: To ensure safety and health the avoidance of adverse chemosensory effects is essential at workplaces where volatile chemicals are used. The present study describes psychophysical approaches that provide information for the evaluation of such effects. Methods: By means of a modified staircase procedure the odor (OT) and irritation thresholds (IT) of 15 irritants were determined. These basic chemosensory properties, confining the chemosensory effect range, were investigated in a random sample of 144 persons stratified for gender and age. Those irritants exhibiting high chemosensory potency were selected for the second psychophysical part of the study. Forty-eight persons, again stratified for gender and age, rated the intensity of 13 trigeminal and olfactory perceptions elicited by nine ascending concentrations of the irritants, ranging from the odor to the irritation threshold of the respective substances. Results: Across the investigated chemicals the transition from concentrations eliciting pure olfactory stimulation (OT) to trigeminal stimulation (IT) differed markedly. The carboxylic acids yielded narrow ranges from odor to irritation thresholds, while for the amines (cyclohexylamine, dimethylamine, and trimethylamine) and the esters (ethyl formate and ethyl acetate) these ranges were somewhat wider. The two chemosensory thresholds of ethyl acrylate and ammonia were farthest from each other. Gender and age had only weak impact on the chemosensory thresholds. At present, the results of the intensity ratings could be given for six substances. Among them, the rated pungency for cyclohexylamine, formic acid, and ethyl acetate increased strongest across the nine applied concentrations. Conclusions: By means of these psychophysical approaches a diverse class of chemicals can be described and compared with respect to their chemosensory potency. This information can be used twofold (a) for the evaluation of existing studies reporting sensory irritations and (b) for the design of experimental exposure studies.     

Passive smoking at work

Summary Air pollution due to tobacco smoke and its effects on employees were investigated in 44 workrooms. For this purpose, the concentrations of CO, NO, NO₂, nicotine, and particulate matter were determined, and 472 employees were interviewed about annoyance and irritations.The mean values of the concentrations of the components due to tobacco smoke are: CO = 1.1 ppm, NO = 32 ppb, NO₂ = 24 ppb, nicotine = 0.9 g/m³, particulate matter = 133 g/m³. One third of the measured CO values exceeds a critical threshold of 2 ppm CO due to tobacco smoke.One quarter of the persons reports eye irritations at work. One third of the employees qualifies the air with regard to smoke at the workplace as bad. Forty percent of the interviewed persons are disturbed by smoke. The majority of the employees is in favor of a separation into smoking and nonsmoking rooms. This seems to be the most appropriate preventive measure for the protection of nonsmokers at work.Supported by the Swiss National Science Foundation, grant no. 3.912-0.78     

大学生烦恼与性格关系研究

目的 研究大学生烦恼与性格的关系。方法 随机抽取在校大学生203名,调查其烦恼的原因、宣泄烦恼的方法,同时用艾森克（EPQ）人格问卷测试其性格。结果大学生烦恼的原因有学习压力、前途渺茫、和同学有矛盾等,宣泄烦恼的方法有向同性朋友诉说、睡觉、听音乐或跳舞、看课外书、让时间淡忘、吃零食、上街购物等;性格中N分值较高、L分值较低者烦恼较多（P〈0．001或0．01）,性格中N分值较低、L分值较高者宣泄效果较好（P〈0．01或0．05）。结论 烦恼、宣泄烦恼能力与性格有关。     

Luftverunreinigung durch Tabakrauch in Gaststätten

Summary In four restaurants we studied the degree of air pollution due to tobacco smoke and its annoying effects on 360 guests. The concentrations of carbon monoxide (CO), nitrogen monoxide (NO), nitrogen dioxide (N0₂), sulfur dioxide (S0₂) and acrolein (CH₂CHCHO) were determined. It appeared, that the differences = indoor concentration — outdoor concentration for CO and NO can be used as indicators to estimate the degree of air pollution due to tobacco smoke.In three of the analysed restaurants we measured very low tobacco induced values of CO and NO (mean values: 0 to 1.1 ppm CO and 0 to 69 ppb NO). These concentrations are harmless to the health of the guests. Higher values were measured in a badly ventilated tavern (mean values: 3.3 ppm CO and 156 ppb NO). These values, too, may be considered harmless. With these exposures, however, other substances caused irritations and annoyance (12 % of the 360 guests indicated moderate to strong eye irritations).     

Road traffic noise annoyance in Amsterdam

Summary 3445 persons living in Amsterdam (1507 male and 1938 female), aged 41–43 years, participated in an investigation in which the relationship was studied between the (measured) road traffic noise in front of the houses in which the participants lived, and the (reported) resulting annoyance and sleep disturbance.We found a smaller number of persons with annoyance and sleep disturbance than we had expected as a result of other investigations. Considerable differences in the annoyance experience were found for different categories of noise-sensitivity. Furthermore, a negative appreciation of other environmental noises and of the living environment increased the prevalence of traffic noise annoyance.Noise sensitivity and this appreciation are mutually dependent: noise-sensitive people have a greater risk of being annoyed by other sounds (aeroplanes, neighbours, work) as well, and they have less appreciation of their living environment. Noise-sensitivity appears to be more strongly represented amongst persons with a higher socio-economic status. In favour of the point of view that an important contribution to annoyance is of nonacoustic character, is the finding that both annoyance and sleep disturbance are greater amongst people who keep their windows closed at the exposed side of their home.     

Annoyance and health risk caused by military low-altitude flight noise

Summary Effects of noise of low-flying military jet aircraft were investigated from demoscopic and epidemiological points of view. Areas with different low-altitude flight noise exposure were compared with one another as to subjective annoyance, casual blood pressure and ear symptoms. With the same energy equivalent sound pressure level (Leq), the subjective disturbance caused by military low-altitude flight noise was essentially greater than that due to ordinary flight noise (in the neighbourhood of civil airports). A comparison of several areas revealed that frequencies of ear symptoms (tinnitus lasting more than one hour and permanent hearing threshold shifts of > 30 dB) were higher only in areas where maximal flight noise levels considerably exceeded 115 dB (A) accompanied by rapid noise level increases. Blood pressure measurements yielded significantly higher values (group difference 9 mm Hg systolic) in girls living in these highly exposed areas. Acoustic limits are proposed with respect to public health.     

Effects of noise on mental performance with regard to subjective noise sensitivity

Summary Objective and subjective effects of moderate levels of recorded traffic noise [L_eq = 55 dB(A) and 75 dB(A)] on mental performance were studied in a laboratory setting. A total of 45 subjects (23 males and 22 females) were investigated with respect to subjective noise sensitivity (SNS). Four cognitive tasks were applied involving different psychological functions: Short-Term Memory (STM), Search and Memory 5 (SAM 5) (vigilance), Hidden Figures (HF) (spatial reasoning) and Mental Arithmetic (MA) (parallel processing). Three groups of 15 subjects were defined according to their scores on Weinstein's Noise Sensitivity Scale as tolerant, moderately sensitive or highly sensitive to noise. A similar level of performance was observed in the three groups under quiet conditions [30 dB(A) L_eq], but under noisy conditions significant differences (P<0.05) were seen between them on the STM (words) and MA (total results) tasks, and the lowest performance accuracy was demonstrated by the noise-sensitive subjects. SNS was the primary factor responsible for these differences. There were no significant differences between the groups in respect of the SAM 5 and HF tasks, under either quiet or noisy conditions. Annoyance while performing tasks under noisy conditions was regularly and significantly higher among subjects judged to be noise sensitive on Weinstein's scale, as compared with those judged to have low or moderate SNS.