Combined Effects of Environmental Factors BOOK OF ABSTRACTS Edited by Olavi Manninen The Academy of Finland, The Research Council for Medicine, c/o Department of Public Health, Medical Faculty, University of Tampere, PO Box 607, 33101 Tampere, Finland Third International ICCEF Conference on The Combined Effects of Environmental Factors is held in Tampere, Finland, at the Hotel Ilves on 15-18 August 1988, under the auspices of The International Society for Complex Environmental Studies (ISCES) in cooperation with many internationally honored experts, companies and organizations representing versatile competences and scholarships. The Local Organizing Committee contains representatives of different fields; its members are Minister Mr. Jarmo Rantanen, Member of Parliament Mr. Matti Hokkanen, Mayor of City Heinola Mr. Jarkko Paronen, Vice Director Mr. Pekka Kari, Managing Director Mr. Rafik Neuman, General Director Mr. Mauno Ahonen, Marketing Director Mrs. Pirjo Hallama, Chairman Mr. Olavi Manninen, and Secretary General Mrs. Ritva Manninen. The Conference Secretariat is comprised of Mr. Olavi Manninen, Mrs. Ritva Manninen, Mrs. Merja-Riitta Ryynänen, Mr. Antti Perttula, Mr. Harri Airaksinen, Mr. Glen Orlando, Miss Tuula Keinänen, Mr. Kari Peltola, Miss Saila Pitkänen, and Mr. Seppo Siuro. This Book of Abstracts consists of 55 reviewed, accepted, and edited abstracts involving presentations at the conference. RESEARCH PROGRAM ON THE COMBINED EFFECTS OF ENVIRONMENTAL FACTORS Tampere, Finland Publishing Office S. Siuro, Tampere, Finland Printed in Finland by Pk-Paino Oy, Tampere, Finland 1988
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Combined Effects of Environmental Factors
BOOK OF ABSTRACTS
Edited by
Olavi Manninen
The Academy of Finland, The Research Council for
Medicine, c/o Department of Public Health,
Medical Faculty, University of Tampere,
PO Box 607, 33101 Tampere, Finland
Third International ICCEF Conference on The Combined Effects of Environmental
Factors is held in Tampere, Finland, at the Hotel Ilves on 15-18 August 1988, under
the auspices of The International Society for Complex Environmental Studies (ISCES)
in cooperation with many internationally honored experts, companies and
organizations representing versatile competences and scholarships.
The Local Organizing Committee contains representatives of different fields; its
members are Minister Mr. Jarmo Rantanen, Member of Parliament Mr. Matti
Hokkanen, Mayor of City Heinola Mr. Jarkko Paronen, Vice Director Mr. Pekka Kari,
Managing Director Mr. Rafik Neuman, General Director Mr. Mauno Ahonen,
Marketing Director Mrs. Pirjo Hallama, Chairman Mr. Olavi Manninen, and Secretary
General Mrs. Ritva Manninen. The Conference Secretariat is comprised of Mr. Olavi
Manninen, Mrs. Ritva Manninen, Mrs. Merja-Riitta Ryynänen, Mr. Antti Perttula, Mr.
Harri Airaksinen, Mr. Glen Orlando, Miss Tuula Keinänen, Mr. Kari Peltola, Miss
Saila Pitkänen, and Mr. Seppo Siuro.
This Book of Abstracts consists of 55 reviewed, accepted, and edited abstracts
involving presentations at the conference.
RESEARCH PROGRAM ON THE COMBINED EFFECTS OF ENVIRONMENTAL FACTORS
Tampere, Finland
Publishing Office S. Siuro, Tampere, Finland
Printed in Finland by Pk-Paino Oy, Tampere, Finland 1988
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
Welcome Address
The complex environmental conditions and their interactions are among the
most central and problematic questions in the field of traditional medicine,
public health, environmental health, occupational health, toxicology, labor
protection, ergonomics, environmental technology and environmental
planning. The study of such combined effects is thus of current interest not only
in scientific terms, but also as far as everyday life is concerned.
The two previous conferences have unambiguously proved that plausible
progress and concrete results can be achieved in this topical area. To ensure the
continuation and nourishment of the international process The Third
International Conference on The Combined Effects of Environmental Factors is
held on 15 - 18 August 1988 in Tampere, Finland, at the Hotel Ilves.
We are very delighted to note that once again our international conference is
attended by a great number of distinguished researchers and experts, whose
research reports cover the latest top achievements in the study of
environmental factors.
We wish that your stay and work here in our hospitable city of Tampere will
prove both productive and pleasurable, and will encourage us to persistently
continue our efforts to gain ever better understanding of the complex
phenomena involved in this field of research.
Olavi Manninen
Chairman
Editor-in-chief
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
[1] COMBINED WORKLOAD, METHODOLOGICAL CONSIDERATIONS ON THE PRESENT RESEARCH
Van Dormolen M, Hertog CAWM
Dutch Institute for the Working Environment (NIA), Amsterdam, Netherlands
In an extensive literature review, the available studies on combined workload were
collected. The literature search resulted in approximately 300 studies of which the
majority was published within the last 10 years. In this review all factors concerning
the structure of work are defined as stressors. This definition includes factors
stemming from the structure of the task itself, from environmental factors, from the
formal conditions of employment and from the working relations. This paper deals
with a number of methodological considerations concerning the analysis of
combined workload and holds critical comments on premises and methods scientists
are dealing with this subject. Among the subjects that will be discussed are: 1The
necessity of a broader concept of combined workload than one restricted to
environmental factors. This is illustrated with examples of interaction between
environmental factors and the task structure, 2The (lack of) validity of performance
measures as indices of workload, 3The structure of post-work tests as a confounder in
the assessment of workload, 4The influence of the choice of subjects from homogenous
populations as male students or military personnel on the external validity of the
results; the need to focus more on high risk groups, 5The definition of the concepts of
interaction, synergism and antagonism and their usefulness in the application of the
results of experimental research in existing work situations, and 6Laboratory versus
field studies, and their complementary function.
[2] SOME METHODOLOGICAL AND PRACTICAL ASPECTS OF COMBINED
EFFECTS OF ENVIRONMENTAL FACTORS
Izmerov NF
Institute of Industrial Hygiene and Occupational Diseases, USSR Academy of Medical Sciences,
Moscow, USSR
Studies on combined effects of chemical, physical and biological environment
have become important nowadays. Many researches study dose-effect
relationship to determine the isolated effect of a factor. However, in real
conditions we have to deal with multifactorial effect. It is a combination of work
and non-work exposures, physical and mental load, negative social
consequences, bad habits and style of life, personal perceptibility. The mixture
of these exposure elements may cause quite a number of systemic diseases. We
suggest different indices to value effects of factor complex, for instance, total
population morbidity.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
Epidemiologic researches have shown that changes in health in 38.0 %
depended on work conditions, in 20.0 % - due to environmental
contamination (i.e. air and water pollution), and in 27.0 % - due to social factors
and stresses. The problem can be settled only by a multiple study using
experimental, clinical and epidemiological investigations.
[3] THE EFFECTS OF NOISE, HEAT AND VIBRATION ON A COMPLEX TASK
Sandover J
Department of Human Sciences, University of Technology,
Loughborough, Leicestershire, England
One might expect a mix of environmental stressors to interact with
each other as regards their effect on task performance. However, it
is not easy to carry out applied investigations on this as one has to
take into account the problems of "direct" versus "indirect"
influences, differences in stressor intensity and characteristic,
exposure duration, task complexity and operator strategy and tactics,
and task realism. We have attempted to ameliorate these problems by
using a functional approach to the design of our computer -based,
complex, information processing tasks by using large clear displays
and large keys for simple responses, by using heat, noise and vibration
stressors of similar characteristic and level to normal transport
situations, and by using long exposures in a workaday situation for
the subjects. Our results show that complex, information processing
tasks are affected by environmental stressors but that the interactions
are still difficult to explain.
[4] WORKLOAD, PERFORMANCES AND PHYSIOLOGICAL RESPONSE UNDER ENVIRONMENTAL AND TASK LOADING STRESS
Von Gierke HE, Albery WB
Biodynamics and Bioengineering Division, Armstrong Aerospace Medical
Research Laboratory, Wright-Patterson AFB, Dayton, Ohio, USA
The effects of biodynamic stressors (two levels of noise, two levels of
sustained acceleration) and dual psychomotor task difficulty (8 degrees of
difficulty) on performance, physiological response and subjective workload
assessment were studied on 9 subjects during 60 seconds exposures. The
results indicate that biodynamic stressors, as well as task difficulty,
adversely affect subjective operator workload without necessarily affecting
objective task performance. Most physiological workload measures do not
correlate well with the subjective workload assessment.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
[5] COMBINED EFFECTS OF NOISE AND VIBRATIONS ON PERFORMANCE AND PHYSIOLOGICAL ACTIVATION
Cnockaert JC, Damongeot A, Floru R
Department of Environmental Physiology, Institut National de Recherche et de
Sécurité (INRS), Vandouevre, France
The purpose of this study was to investigate the combined effects of noise and vibrations
on performance and physiological activation in a vigilance task during simulated
driving. The driving scene and symbolized vehicle were generated by a computer.
Interrupted vertical lines of equal lengths were sweeping along the central axis of the road
from top to bottom of the screen. They constituted the irrelevant signals in the vigilance task.
The relevant signals were slightly longer lines occurring randomly among the others. The
subjects were required to maintain the vehicle in the middle of the right lane and to
respond as far as possible to relevant signals by depressing the brake pedal. The
experiment had four conditions: control (C), noise (N), vibrations (V) and noise plus
vibrations (N+V), similar to those in a real truck cabin, i.e. noise with dominating
low frequencies and a A weighted level of 80 dB and vertical broadband vibrations
with a 2.5 Hz peak and a Z (axis) weighted acceleration of 0.9 m/s2. The task lasted two
hours. Response time to relevant signals (RT), omission rate (0), steering control
of vehicle position, heart rate (HR), alpha Index (AI) and beta Index (BI) determined
from EEG were continuously recorded. The average RT and 0 do not show significant
changes across the conditions but the variability of RT increases under isolated or
combined effects of noise and vibrations. Mean HR and BI increased and AI decreased in
stress conditions. These changes were more pronounced under combined stressors
(N+V). The RT and the steering control tended to decrease in the second half of the task.
The progressive decline of HR and BI and progressive increase of AI over time in (C),
(N) and (V) conditions became much more marked in (N+V) condition. Thus, cerebral
and autonomic arousal increase under stress conditions without significant
performance changes. The cerebral and autonomic arousal decline over time and this is
not related to their average level. Both noise and vibrations act in the same direction but
the final effect of their combination seems to be controlled by cortical reticular
homeostasis mechanisms.
[6] COMPARATIVE MAGNITUDES OF PERFORMANCE CHANGES RESULTING
FROM ENVIRONMENTAL STRESSOR AND MOTIVATIONAL VARIABLES
Strong RJ
Institute of Naval Medicine, Alverstoke, Gosport, Hants, United Kingdom
The Institute of Naval Medicine at Alverstoke has conducted a series of trials
investigating the effects of the gas HALON 1301 on task performance. HALON
1301 had been proposed for use in a total flooding firefighting system at sea, and the
primary objective of the studies was to identify possible health and performance
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
hazards of the gas, which is a narcotic in low concentrations. The trials design used a
series of repeated-measures experimental studies, small groups of subjects being
confined within a special research chamber with associated living accommodation,
each group for up to three weeks. While not the major purpose of the trial, we
were able to observe effects of variations in leadership competence, group
cohesiveness, and the occurrence of unexpected events. These findings will be of
interest to those concerned with the performance of small groups, and in particular
provide quantitative evidence of the comparative magnitude of performance changes
due to group characteristics and processes and to more conventional external
stressors. Our observations show the following: 1The performance of one group
(known to one another and with a clear leader) remained consistently stable
throughout a three week period, while another group's (of mixed background, not
known to one another, and with no clear leader) did not, despite initial training
performance of the two groups being comparable. 2The occurrence of a significant
event (denial of a request for an expected social activity) was sufficient to cause a huge
change in group performance. This change was of considerably greater magnitude
than that due to the experimental stressor variable (the firefighting gas). 3The
magnitude of this effect was independent of the degree of task practice and suggests
that motivational changes may be of equal significance for all tasks, although
changes due to external physical stressors may be greater for less well practiced
tasks. It may be concluded that: 1Good leadership and high group cohesion can lead to
greater consistency and predictability of small group performance, 2Performance
changes due to motivational factors can be considerably greater than those due to
environmental stressors, and 3Overlearning of tasks may provide resistance to increased
environmental stresses, but not against motivational variations.
[7] COMBINED EFFECT OF WHOLE-BODY VIBRATION AND LOW-
FREQUENCY NOISE ON THE HUMAN ORGANISM
Suvorov GA
Department of Physical Factors, Institute of Industrial Hygiene and Occupational Diseases
of USSR Academy of Medical Sciences, Moscow, USSR
The mass investigations of operators exposed to noise and vibration of low
frequency range (lorry and car drivers, operators of concentrators and agricultural
tractors, weavers) showed that combined effect of those factors manifested in signi-
ficant changes of functional state of vestibular analyzer, hearing loss mainly on low
audiometric frequencies and early development of vegetative vascular dysfunction that
revealed the synergic character of interaction and mutual deteriorative effect of noise and
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
vibration. Combined exposure to noise and vibration resulted in their sub additive effect on
functional state of main physiological systems. The results of field investigations and conducted
experiments underlines the necessity of differentiated approach to hygienic rating of noise and
vibration as the most wide-spread factors of working environment taking into account the
peculiarities of their combined effect to estimate real load on operator and to maintain good
health and optimal conditions of work.
[8] A CONTRIBUTION TO IDENTIFICATION OF NONLINEAR BIODYNAMIC OSCILLATORY MODEL OF MAN
Demic M
Faculty of Mechanical Engineering, Kragujevac, Yugoslavia
In optimizing oscillatory parameters of motor vehicles, there is a need to use
biodynamic oscillatory models of human body. Since all the oscillatory excitations that a
man is exposed to in vehicle, are most often random, and sometimes shock or
harmonic, use of many well-known models (described in literature) would not give
acceptable results in all characteristic cases. Therefore, based on the test obtained data on
input mechanical impedance of a man in passive sitting position, this paper has made
an attempt to identify non-linear biodynamic oscillatory model of a man namely, a
man is approximated by three concentric masses, mutually connected by non-linear
and linear damping elements. Using electronic computer various parameters were
identified. These parameters enable very good simulation of human body behavior
under influence of random, shock and harmonic excitation. The paper also indicates
that it is better to use simple non-linear than complex linear biodynamic oscillatory
models in optimizing characteristics of motor vehicles.
[9] THE INFLUENCE OF NOISE, INFRASOUND AND TEMPERATURE ON DRIVER PERFORMANCE AND WAKEFULNESS DURING STANDARDIZED CONDITIONS
Nilsson L, Morén B, Törnros J
Swedish Road and Traffic Research Institute, Road User and Vehicle Division,
Linköping, Sweden
The environment within a motor vehicle is believed to affect the
driving performance and wakefulness of the driver. Knowledge, about
how and to what extent the driver is affected, is however lacking due to
the fact that very few realistic studies have been carried out. The effects on
traffic safety, if any, are therefore also unknown. The objective of the
present study was to assess the influence of noise, infrasound and
temperature on performance and wakefulness of drivers driving a simulator,
where they can be exposed to realistic and controlled environmental as well as
driving conditions. 48 young, healthy individuals drove the VTI driving
simulator for about 4 hours.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
They were exposed to different combinations of noise, infrasound and
temperature. Two values of each of these variables, representing low and high
levels measured in real traffic, were used. The experimental design thus
included 8 different experimental conditions (combinations) with 6 drivers
exposed to each condition. As dependent measures of driving performance we
used steering precision, speed keeping and stimuli-induced reaction time,
while EEG, ECG and EOG were recorded for the assessment of wakefulness.
Audiometry was carried out, before and after exposure, to observe possible
temporary hearing losses. The answers from questionnaires given to the
subjects indicate their subjective evaluations of sleepiness and impaired
performance. The experimental part of the study was finished only this March
and interpretation and assessment of obtained data are still going on. The
results will be available and discussed at the conference.
[10] METHODICAL STATEMENT FOR COMPUTER-AIDED INVESTIGATION OF THE COMBINED EFFECT OF NOISE, CLIMATE AND ILLUMINATION
Rentzsch M, Joiko K, Prescher W
Dresden University of Technology, Department of Work Sciences, Dresden,
German Democratic Republic
Working environmental factors can impair both fitness and wellbeing of
man, particularly with their combined effect. Especially in case of mental
performances, results will be modified by the level of cognitive activity
requirements. At the example of activities modelled for automated flexible
manufacturing systems impacts of load onto man caused by the working
environment such as combinations and variations of noise, climate and
illumination will be investigated. By means of a three-dimensional
experimental design performance parameters (number of errors, reaction time),
physiological indicators (heart rate) and psychic indicators (ratings) are in-
volved into experimental methods. In addition to data detected objectively,
sensation of combined load at simultaneous and immediately successive
presentation of two conditions was investigated using the method of pair
comparison as a subjective procedure. For instance, noise and illumination
levels were presented in a contrary mode in order to reduce the high
number of pairs to be evaluated, decisively. The results of the objective
investigations tend to indicate an increasing load of test persons during the
course of test, which is enhanced at rising load due to environment as well
as at growing activity requirements. Test series using the method of pair
comparison in terms of illumination and noise intensity suggest that the
effect of noise dominates concerning the feeling of comfort. Finally,
equivalence considerations of objective and subjective methods in terms of
experienced impairment due to environmental conditions and their impact to
strain and performance will be presented in order to draw conclusions for
measures of a complex design of working environment.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
[11] AGED AND YOUNG MEN UNDER COMPLEX ENVIRONMENTAL
EXPOSURES INCLUDING MENTALLY AND PHYSICALLY LOADING TASKS
Manninen O
The Academy of Finland, c/o Department of Public Health, Medical Faculty,
University of Tampere, Tampere, Finland
This study is part of a multi-stage research project into the combined
effects of different environmental factors on the functions of the human
body. This study in particular was set out to explain the significance of
age (and working hours) in changes in the body functions observed when
the subjects were exposed separately or simultaneously to noise and
vibration while performing physically and mentally loading work at an
elevated temperature. The study was realized as a type 2-2-2-2-3 factorial
experiment yielding a total of 48 exposure combinations. The experiment
were participated by 192 healthy, non-smoking male subjects, 64 of whom
were students and 128 Tampere City Transport bus drivers. Half of the
drivers (64) were under 39 and half were over 40 years of age. Before
the exposure tests all subjects were subjected to a thorough medical
examination and physical fitness tests, an enquiry and an interview in
order to chart, among others, such things as their exposure and working
history. To determine the daily exposure doses various measurements were
made with equipment in bus cabins during driving both in winter and in
summer. One personal test took 5½ hours and it was composed of several
consecutive exposure periods of 16 minutes with a break of 4 minutes
between. During the breaks the subjects were either resting in sitting
position in the vibration chair or were subjected to various measurements
to trace changes in their body functions. During the all tests the subjects
were working on a choice reaction apparatus. The classes of mental work
were 1) no competition and 2) competition on least errors in mental arith-
metic motivated by interim information and monetary rewards. The
classes of physical workloads were 1) work at 2 W and 2) work at 7 W.
The noise classes were 1) no noise and 2) a stable 90 dBA broadband
noise. The vibration classes were 1) no vibration and 2) a stochastic
broadband whole body vibration with a frequency range of 2.8-11.2 Hz
(along Z-axis; acceleration 2.12 m/s2). Changes in body functions were
analyzed on the basis of temporary threshold shifts of hearing, blood
creatine kinase activity levels and urinary catecholamine excretion rates.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
The results showed that changes in body functions were largely
dependent on the exposure combinations the subjects were exposed to. The
same exposure combinations would have a slightly different effect on
young subjects than on older subjects.
[12] VESTIBULAR EVOKED POTENTIALS - A NEW METHOD FOR STUDY OF
THE COMBINED EFFECTS OF ENVIRONMENTAL FACTORS
Trinus KF
Research Institute of Labour Hygiene and Occupational Diseases, Kiev, USSR
Progress in the industries and high-speed traffic caused the increase of the number of the
people suffering from the vestibular disorders. That is why the search for new diagnostic
methods is very important. In this context the special place is reserved for vestibular
evoked potentials, the method which will show the particular features of information pro-
pagation in the special areas of the brain. The subject of this study is the analysis of
the parameters of the longue-latency vestibular evoked potentials in healthy
persons and the changes of these parameters after the combined effects of
environmental factors. Vestibular sensitivity analysis is used for recordings and data
proceeding. It appears that the threshold of the vestibular evoked potentials lies at the
acceleration range of 5.7±1.8 cm/s2. The potentials consist of the 3 main extremums: P1,
N1, and P2, the latencies of which at the threshold level are: 31.3±7.2 ms, 69.1±9.1 ms, and
157.6±10.5 ms. The increase of the acceleration results in the shortage of the latencies
which may be reflected by the linear regression equations based on the use of the least
squares method: P1 = -0.69x + 33.6, N1 = -0.44x + 64.0, and P2 = -0.13x + 145.1, where x -
acceleration, factor a shows the slope of the regression line, factor b - theoretical
latency of the peak at the threshold level. The data presented shows that the most
acceleration-dependent is P1, and the least P2. The variability analysis shows some
individual and group specifics, for example, for males the least variable is P1 while
for females N1. The preliminary data shows that after the action of vibration, noise
and workload in different combinations as to the intensities the vestibular threshold levels
rise, latencies of the peaks increase especially at the small acceleration, coefficients of
variation and factors a and b in linear regression equations also increase. The most
impressive changes are caused by vibration, the least by noise. We hope that the method of
vestibular evoked potentials will be useful for studies of the combined effects of
environmental factors.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
[13] A STUDY OF THE EFFECTS OF LOW-INTENSITY NOISE AND MILD HEAT
ON COGNITIVE PERFORMANCE AND THE FIVE-CHOICE SERIAL REACTION
TASK
Hygge S
Human Criteria Laboratory, National Swedish Institute for Building Research,
Gävle, Sweden
From the arousal theory and from the perspective of an assumed de-arousing
effect of mild heat and an arousing effect of noise, it can be predicted that more
demanding cognitive tasks would show an antagonistic interaction between
noise and heat. Alternative theoretical approaches, such as information
overload theories or shift in cognitive strategy theories have a problem in
explaining how one stressor can cancel the effects of another. Present study was
designed to further explore interactions between mild heat and low intensity
noise on an array of cognitive performance tasks and on the five-choice serial
reaction time task. In a factorial design two levels of ventilation noise (38 dBA
and 53 dBA) were crossed with two temperatures (19⁰C and 27⁰C). A total of
64 subjects (32 males, 32 females) completed the experiment, and the four
experimental groups had similar distributions of sex and age. The sessions
lasted 2 hours 20 minutes while the subjects worked with mental arithmetic,
acetonitrile, and hydrogen sulfide) - most workers reported daily exposure to at least 5
different solvents and related chemicals. Health complaints (noted at least 3 times per
week when working) in laboratory workers vs. controls included eye irritation (31 %
versus 4 %, p<0.001), skin irritation and rashes (16 % versus 4 %), headache (36 % versus
19 %) and dizziness (22 % versus 12 %). Controlling for potential confounders such as
age, sex and smoking by ANOVA did not eliminate higher reporting by exposed workers,
RBC counts showed a clear shift between exposed and control workers: median
values were lower in solvent-exposed workers, which might be attributed to
frequent use of benzene and/or toluene contaminated with benzene. In several workers, a
longitudinal trend of decreased RBC values was also observed. Biochemical
values (AP, GOT) were not different among the two groups; however, ALA values were
increased for the urines of laboratory workers versus controls. In all, over half of the
workers exhibited at least 2 self-reported health complaints possibly due to mixed
solvent exposure and RBC values below the median for their sex. Selection of an
appropriate indicator battery for individuals with multiple overlapping and
potentially interacting exposures is discussed.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
[24] COMBINED EFFECT OF JOB DEMANDS AND JOB DECISION LATITUDE ON LEAD IN BLOOD
Ulenbelt P, Lumens M, Cron H, Herber R, Meijman T
Work and Health, Coronal Laboratory, Amsterdam, Netherlands
The effects of interaction of formal job characteristics (job demands and job
decision latitude) and hygienic behavior at the workplace on uptake of
airborne lead and on lead in blood are studied. Workers in an
electric accumulator factory (n=30) responded to a questionnaire.
Moreover their hygienic behavior was observed during five working
days. Lead in air (PbA) and lead in blood (PbB) was measured. The
correlation between PbA and PbB is R (PM)=0.42. The correlation
between job decision latitude and PbB is R ( P M ) =0.55 and between the
use of personal protection devices and PbB is R(PM)=0.46. Job demands and
personal hygienic habits are not correlating with PbB levels. Job
demands and job decision latitude are both negatively related to
the use of personal protect ion devices (respectively R ( P M )=-0.59).
Moreover, a combined effect of job demands and job decision
latitude on PbB is demonstrated. Both job decision latitude and the
use of personal protection devices explain more variation in PbB
levels than the exposure to PbA does.
[25] THE RELATIVE IMPORTANCE OF NOISE WITHIN THE SCOPE OF COMBINED STRESS FACTORS AT WORKPLACES
Schwarze S, Jansen G
Institute of Occupational Medicine, University of Düsseldorf, Düsseldorf, Federal
Republic of Germany
A longitudinal study into the effects of noise on health in comparison to other
stress factors of the workplaces was carried out with a sample of 29 employees
of a military service unit. Out of 31 stress factors 6 variables relating to the
working conditions proved to be relevant for health state. Analyzing the
predictors for general health by calculating multiple regression, time stress
was the most important variable, followed next by noise annoyance. Subdividing
the general health score into 11 different groups of diagnoses, still two third of the
criteria showed significant explanations of variance. The relative importance of
the predictors varied between the groups of diagnoses. Time stress was the
dominating variable for the group of gastrointestinal diseases and for the group
of urogenital diseases.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
For neuro-vegetative disorders and diseases of ear, nose and throat, time stress as
well as noise annoyance and duration of noise exposure were relevant predictors.
Cardiovascular disorders were mostly related to the noise variables. Evaluation
models are presented how to assess noise effects.
[26] INVESTIGATIONS OF THE RISK OF HEARING DEFECTS FOR THE
OCCUPATIONAL GROUPS OF WELDERS AND PLANT ASSEMBLY
WORKERS
Rentzsch M, Minks B
Department of Work Sciences, Dresden University of Technology, Dresden,
German Democratic Republic
Welders and plant assembly workers represent a high proportion of
occupational diseases caused by noise. This suggests primarily a considerable
risk of hearing defects. By field studies and findings of occupational
medicine of work the situation in terms of occupational hygiene was
analyzed and characterized. The detected hearing losses of probationer
groups cannot be described by the Dresden noise dose model and, thus,
they can't be understood merely as a consequence of noise load. The highly
increased risk of hearing defects in comparison to the dose model is
intensified by the combined effect of noise and chemical pollutants (CO). For a
description of the combined effect and extension of the noise dose model is
proposed describing an additional risk of hearing defects as a function of
exposition time and intensity. The ototoxic effect of carbon monoxide is well-
known. The results represent a valuable basis for a more precise specification of
noise limiting values from the aspect of a combined effect including carbon
monoxide
[27] ADDITIONAL EFFECT OF HIGH LEVEL SHOOTING IMPULSES TO THE GENESIS OF SENSORY NEURAL HEARING LOSS
Pekkarinen J1,Starck J1,Pyykkö I2 1Institute of Occupational Health, Vantaa, Finland 2University Hospital of Helsinki, Helsinki, Finland
Sensory neural hearing loss (SNHL) may be caused either by a long term
exposure to noise leading to the metabolic changes in the inner ear or by high
level impulses which produce immediate damage in the cochlea. The criteria
level for immediate damage is still a matter of controversy but according to
several recommendations peak levels above 140 dB should be avoided.
Shooting is known to produce peak levels up to 185 dB. We analyzed the effect of
non-occupational and military shooting impulses on the hearing loss in a group
of 199 forest workers exposed to noise from chain saws.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
Our goal was to clarify the relative role of different factors for the incidence of
SNHL which has not diminished in Finland during last ten years in spite of the
wide use of hearing protectors and noise control measures. The total amount of
shooting impulses, weapons and hearing protectors used were inquired in
addition to the occupational history. The attenuation of impulse peak levels by
hearing protectors was measured for the most common weapons. Subgroups
were contrasted by the lowest and highest quartiles of the total exposure to
shooting which was summed for each individual using logarithmic conversion.
Exposure to chain saw noise was calculated as a noise immission level by
Robinson's model including age, noise exposure time and level. The matching
criteria for the contrasted 12 pairs of workers were: no ear diseases, age within
10 years, noise immission level within 5 dB, use of salicylates within 30
tables/month, diastolic blood pressure within 10 mm/Hg, LDL-cholesterol
concentration within 2 mmol/l, same status for smoking and vibration-induced
white fingers. The bilateral hearing level (mean±sem) for the low impulse
exposure group was 21.7±4.6 dB at 4 kHz and 24.4±5.0 dB at 8 kHz, and for
high impulse exposure group 30.8±6.2 dB at 4 kHz and 34.6±6.6 dB at 8 kHz. The
forest workers with higher exposure to shooting impulses had significantly
higher hearing loss at 4 kHz (p<0.l) and at 8 kHz (p<0.05) according to a one-
tailed paired t-test. The peak levels of large caliber weapons exceeded 140 dB
inside the hearing protectors which together with the analysis by matched pairs
revealed that shooting impulses were contributing to the hearing deterioration
in persons exposed to occupational noise.
[28] SMOKING AS A RISK FACTOR IN SENSORY NEURAL HEARING LOSS
Starck J1, Pekkarinen J1, Pyykkö I2 1Institute of Occupational Health, Vantaa, Finland 2University Hospital of Helsinki, Helsinki, Finland
Smoking is generally considered to contribute to the vascular diseases.
However, its role in the development on sensory neural hearing loss (SNHL)
has been controversial. Smoking has been proposed to influence inner ear
directly by the chemical agents in smoke or by circulatory changes in the inner
ear capillaries. While some researchers have shown correlation between
smoking and SNHL some others have not been able to confirm such a finding.
This may be due to the minor effect of smoking on SNHL compared to other
more profound risk factors. The present study was aimed to evaluate the effect
of smoking alone and together with other risk factors on the SNHL among
workers exposed to occupational noise and vibration. The study comprised 199
professional forest workers and 171 shipyard workers.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
Their exposure to noise and vibration and health status were examined. The
smoking habits were queried and if more than ten years had passed since
quitting smoking, the subject was classified as a nonsmoker. The permanent
hearing level was measured with audiometry in an acoustically treated room.
Effect of age to hearing was corrected by using Robinson's model. The other
risk factors were blood pressure, low density lipid cholesterol concentration,
and presence of vibration induced white finger. The result showed that
smoking without the presence of any other risk factors does not increase the
risk for SNHL, but that smoking in combination with other risk factors
promotes a higher risk than any of the risk factors alone.
[29] EFFECTS OF MULTIEXPOSURES FOR HANDS IN SNOWMOBILE DRIVING
Virokannas H, Hannu Anttonen H, Niskanen J
Oulu Regional Institute of Occupational Health, Oulu, Finland
The aim of the study was to find out the effects of multiple exposures in
snowmobiling and correlated complaints in hands. Vibration syndrome in
hands is caused more in cold than in warm conditions. Hand vibration and cold
have combined effects for circulation in fingers and noise may also have effects
upon circulation. According to the results of the inquiry for reindeer herdsmen
white finger symptom and numbness of hands increased significantly when
snowmobiling exceeded 6000 h (Group III; Table 1). Persons in every exposure
group had used chain saw equally (Mean±SD 1200±1100 h).
Table 1. The use of snowmobiles and prevalence of white finger symptom and numbness of hands ___________________________________________________________________________ Exposuregroup n Age(y) Snowmobile (h) White finger Numbness
[39] CALCULATION AND USE OF PROBABILISTIC SAFETY COEFFICIENT IN HYGIENIC STANDARDIZATION OF SEVERAL FACTORS' COMBINED EFFECT
Dobrovolsky LA1, Svatkov VI2
1Kiev Research Institute for Labour Hygiene and Occupational Diseases, Kiev, USSR 2Kiev Research Institute for General and Municipal Hygiene, Kiev, USSR
Today hygienic standard setting of occupational and communal environmental factors is based
on their isolated hazardous effect when we use an expert safety coefficient resulting from an
arrangement between specialists. Safety coefficient is meant to be a divisor of chronic isolated
action threshold. The result of the division represents a MAC (MAL) maximal allowable
concentration (level) of a factor. The MAC (MAL) thus obtained is liable to ignore the possibility
of the reglamented factor's combined effect with the other ones in a real occupational and
communal environment. In order to get rid of this shortcoming we propose in every separate
case to calculate the safety coefficient basing on the objective information. The latter includes, on
one hand, information on chronic combined exposure to a reglamented factor and,
on the other hand, on the reglamented factor's specific weight in the occupational or
communal environment. Under such an approach, the safety coefficient remains also the chronic
threshold divisor, the division producing a MAC (MAL) of the factor's combined effect.
Nevertheless, the MAC value has another meaning in this case: the MAC (MAL) of a factor
reglamented anew is to take into account the supposition about the possible toxicity of the sum
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
of MACs (MALs) of all the factors supposed to have their share in the combined effect which
should not exceed the toxicity brought forth at the level of the chronic threshold
of a single factor's isolated effect. This approach does not assume the reglamented factor's
combined effect in a real occupational or communal environment to be obligatory; it assumes
just a certain probability of such an effect. That is why the safety coefficient developed is called
probabilistic (PSC). The information necessary for its calculation is also to be
expressed through probabilities: the one of toxic changes under combined exposure to
chronic threshold concentrations of factors and the one of the reglamented factor's allowable
appearance in a real communal or occupational environment. The chronic threshold logarithm
divided by the PSC yields the PMAC (probabilistic MAC) logarithm of the
reglamented factor's combined effect.
[40] COMBINED EFFECT OF THE CNS PHARMACOLOGIC ACTIVATION
AND OF INTELLECTUAL TASKS COMPLEXITY UPON OPERATORS
Navakatikyan AO, Grigorus AG
Research Institute for Labour Hygiene and Occupational Diseases, Kiev, USSR
Three activation levels have been modelled under laboratory conditions; a
moderately decreased one (aminazine intake), an ordinary level (without pharmacologic
impacts), a moderately increased one (caffeine intake). The tested subjects have been per-
forming their work: 1) free pace, 2) in a forced regime, the low, medium and
high working pace alternating, and 3) at one of said paces during the whole of the
experiment. The duration of the experiments made up 3 hours. The task of the
tested subjects was to recognize quickly and correctly photic stimuli, both requiring and
not requiring a response. We registered R-R intervals of ECG, arterial blood pressure, time
of pulse wave propagation through the arteries, GSR integral, indices of short-term
memory, attention, muscular strength and endurance, number of tasks fulfilled, latent
response periods, and errors of task omission and of incorrect response. The results of the
investigation have been analyzed with the help of mathematical statistics methods, inclu-
ding the two- or three-factor analysis of variance. The analysis of data relative to
the forced pace testifies to the selective effect of said factors through different working
periods upon body's functions. During the first 20 minutes of the work the CNS activation
effect tells upon the cardiovascular systems functioning (effect share 65 to 90 % in
different tested subjects). Later on, the activation effect tells upon the response speed (this
factor’s effect share reaches toward the end of the experiment 37 to 76 %). Changes of
the vegetative nervous system activation, according to the GSR data, had considerable indi-
vidual differences. The most substantial effects upon psychophysiological indices among
the factors of activation, intellectual load and work duration all through the investigation,
were proper to the first two ones; the effect of work duration has been shown to be true
for indices muscular strength and systolic pressure only.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
Under a free pace of work the effect of three studied factors was little pronounced. Thus,
the effect of CNS and intellectual load activation upon humans depends upon the
regime of the operator's performance. It has a particular importance for a forced working
pace. The application of variance analysis during the investigation of the combined effect of
CNS and intellectual load activation provides enough information the effect of factor
operators are exposed to.
[41] EXTENSION OF THE ADDITIVE MODEL WITH THE UTILIZATION OF SET
AND THE RESULTS IN THE FIELD SURVEY
Sakurai Y2, Matsubara N1, Noguchi T2, Horie G2
1Department of Housing and Design, Faculty of Living Science, Kyoto Prefectural
University, Kyoto, Japan 2Department of Architecture, Faculty of Engineering, Kansai University, Osaka, Japan
We have been studied the combined environment of heterogeneous factors noticing that
there always exist several factors in a room. Since a scale specific to one factor
would not express the total effect of several factors, a nonspecific scale has been
used. The method to express the degree of uncomfortableness as a linear combination of the
weight score which was obtained with the Second Method of Quantification of each
environmental factor was proposed, the method to predict the degree of
uncomfortableness in the actual combined environment and its application to the
environmental design was discussed. Thermal environment has been categorized
by dry bulb temperature (DBT; see another article in this publication). This paper aims
to discuss the possibility to extend the additive model of synthesized evaluation with the
utilization of standard effective temperature (SET). To realize different thermal condition,
only DBT and relative humidity (RH) were controlled. The results showed that the success
rate of the prediction was virtually the same as that of the past where RH was fixed. And
the quantified weight scores of each environmental condition were also similar to the
past. The reason why there is a slight different score profile was caused by the slight
inner correlation between the environmental factors. Quantified weight scores for three
environmental factors where thermal, noise and illumination environment are categorized by
SET, Leq and lx, respectively, are obtained on "uncomfortableness" scale. After all, it is
suggested that the additive model is to be extended by introducing SET. Then it is
discussed how the success rates of the prediction of residents' responses in the actual
offices would coincide with those findings obtained in the experimental chamber.
The surveyed offices were three; one was a not air-conditioned office in a university
and the others were the air-conditioned offices in companies. Reasonable results
were obtained, in spite of other factors which were not treated on the quantification.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
[42] EFFECT OF ALCOHOL CONSUMPTION COMBINED WITH OTHER
FACTORS ON BLOOD PRESSURE OF MALE METAL WORKERS
Honda R, Ishizaki M, Nogawa K, Yamada Y, Kido T, Tsuritani I
Department of Hygiene, Kanazawa Medical University, Kanazawa, Japan
Factors affecting blood pressure were studied on 1897 male workers in a metal-
products producing factory. Age of workers varied between 35 and 59 years.
The variables(factors) used in the study were as follows; the questionnaires for
drinking habits and family history of hypertension, age, height, weight, blood
pressure, hemoglobin, hematocrit, red blood cell count, white blood cell count,
serum levels of GOT, GPT, γ-GTP, total cholesterol, β-lipoprotein, HDL-c,
1Department of Public Health, School of Medicine, Kanazawa University, Kanazawa,
Japan 2Department of Environmental Hygiene, School of Pharmacy, Hokuriku University,
Kanazawa, Japan
Both vibration and cold stress have been well known to be ones of stressors that
cause an imbalance of the homeostasis of organisms. In order to clarify the
mechanism in the central nervous systems (CNS) that combined stresses of
vibration and noise produce more dysfunction in the autonomic-neuroendocrine
systems than each stimulus alone, dopamine (DA) turnover rates which is well
known to be most sensitive to stress, were examined in the regional rat brain in the
following 4 groups: 1) Group restrained in special cage as a control of group 2 and
group 3, 2) Group with its hind limbs exposed to vibration at 120 Hz under
acceleration of 4 g for 90 minutes, 3) Group kept in cold room (4°C) for 90
minutes, and 4) Group exposed to these combined stimuli for 90 minutes.
Simultaneously plasma corticosterone (CORT) concentrations and gastric ulcer
formation were examined as autonomic-endocrine function. The results were as
follows: 1CORT and DA turnover rate (homovanillic acid (HVA) and/or (HVA/DA
ratio)) in the frontal cortex (FC) in vibration group increased compared to that of
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
control group, 2CORT, ulcer formation and DA turnover rates in FC and the
nucleus accumbens (NAc) in cold exposure group were increased compared to that of
control group, while DA turnover rate in the hypothalamus (HYP) was decreased, 3CORT and DA turnover rate in FC in group exposed to combined stimuli were increased
as compared to that of cold exposure group but DA turnover rate in HYP were
decreased, 4There were no significant differences in any items examined between cold
exposure group and combined stimuli group, and 5There were no significant
changes DA turnover rate in the striatum or amygdala between any group. These
results show that the appearance of the combined effect on CORT deeply related to
DA turnover in FC increased by the combined stress, that is, psychological stress induced
by emotion which is something common to these physical stress, and indicating
mesocortical DA neuron innervating to FC plays a part in regulation pituitary-
adrenal system.
[45] INTERACTION OF NOISE AND VIBRATION
Byrne C, Henderson D
Department of Communicative Disorders and Sciences, State University of New
York at Buffalo, Buffalo, New York, USA
Whole body vibration has been suggested to be a potentiating agent in the
condition of noise induced hearing loss. These experiments were designed to
evaluate the effect of vibration frequency and acceleration in the interaction of
noise and vibration. Three groups of chinchilla were used as subjects and
hearing was monitored using an evoked response recorded from a chronic
electrode in the inferior colliculus. The first group (n=6) received an octave band
of noise (octave band centered at 500 Hz) at 100 dB SPL for 6 hours per day for
20 days. The second group received the same noise for 10 days and on day 11
vibration was added (14-20 Hz at 0.l g rms) and at day 16 the level was
increased to 1.0 g rms. The third group had the same exposure sequence as the
second, but the vibration frequency was 63-89 Hz. The vibration frequencies
were chosen to approximate either the body resonance (14-20 Hz) or the head
resonance (63-89 Hz); however, it is difficult to specify a single resonant
frequency where the body is composed of multiple spring/mass systems. The
noise produced approximately 25 - 40 dB hearing loss across the frequencies
tested. The addition of the low frequency vibration did not increase the hearing
loss, but like high frequency vibration increased the hearing loss on the average
of 4 to 8 dB across most frequencies tested. The results are discussed in terms of
agents that potentiate the effects of noise.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
[46] THE INFLUENCE OF WHOLE BODY VIBRATION ON NOISE-INDUCED HEARING LOSS, A REVIEW OF ANIMAL EXPERIMENTS
Hamernik RP, Ahroon WA, Davis RI
State University of New York at Plattsburgh, Auditory Research Laboratory,
Plattsburgh, New York, USA
There is the suggestion in the literature that vibration may potentate the effects of
noise and may pose an increased risk of hearing loss. However in human
experimental studies, which be necessity are limited to low levels of TTS, the
effects measured are consistent but relatively small. A very limited number of
animal studies have also shown an enhanced hearing loss, but the scope of these
studies is limited by a large inter subject variability and small number of subjects.
Also, the high levels of stimulation that were used in some of these animal
experiments were not realistic. Our recent animal studies (chinchilla) have
used a 30 Hz, 3.0 g (rms) cage vibration in combination with continuous noise
(95 dB, 0.5 kHz octave band) and impact noise (114, 119 or 125 dB peak SPL)
exposure paradigms. All exposures lasted for five days. The impact noise
exposures were designed to have an equal total energy. Temporary (compound)
and permanent threshold shifts were measured using evoked potentials. Sensory
cell populations were evaluated with the surface preparation technique. The
results obtained from each of the above paradigms were consistent in showing that
the presence of vibration did not have a statistically significant effect on hearing
thresholds. A parallel set of experiments using a 20 Hz, 2.0 g (rms) vibration is in
progress. Preliminary conclusions are essentially the same as those of the 30 Hz
experiments. The suitability of the chinchilla as an animal model for use in vibration
experiments will also be discussed.
[47] COMBINED EFFECTS OF NOISE AND CISPLATIN
Gratton MA, Salvi RJ, Kamen BA, Henderson D
Hearing Research Laboratory, State University of New York at Buffalo, Buffalo,
New York, USA
One of the most promising chemotherapeutic agents for treating certain types of
cancer is Cis-diamminedichloro-platinum (cisplatin). Unfortunately, one serious side
effect of cisplatin is that it can cause hearing loss, with the incidence of ototoxicity
ranging from 23-61 %. One environmental agent that could potentially exacerbate
the ototoxic effects of cisplatin is high level noise exposure. To determine if intense
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
noise exposure could exacerbate the ototoxic effects of cisplatin, a series of
experiments were carried out using three groups of chinchillas. Group I was
exposed only to noise on days 1-5, 8-12, and 15-19 (octave band noise centered at
0.5 kHz at 100 dB SPL). Group II was given only cisplatin (2.75 mg/kg) on days 6,
7, 13 and 14. Group III received both the noise plus cisplatin as described above.
Group I, given cisplatin alone, showed little or no TTS whereas Group II,
exposed only to noise, developed 35-50 dB of TTS. By contrast, Group III, which was
given both noise and cisplatin, showed approximately 15 dB more TTS than
either Group I or II. There was some recovery in hearing sensitivity; however, the
permanent effects of the three treatments were significantly different. Group III
showed 15-50 dB more PTS at the high frequencies than either Group I or II.
Furthermore, Group III showed substantially greater hair cell loss than either
Group I or II. These results suggest exposure to intense noise during the time of
cisplatin treatment may substantially increase the risk of sensorineural hearing
loss.
[48] PREDICTION OF SYNERGISTIC EFFECTS OF ENVIRONMENTAL AGENTS ON AUDITORY FUNCTION
Fechter LD
Department of Environmental Health Sciences, Johns Hopkins University School of
Hygiene and Public Health, Baltimore, Maryland, USA
The identification of synergistic interactions between environmental factors is
tremendously accelerated when a hypothesized basis for the interaction can be
identified. We are interested in the vulnerability of the auditory system and, in particular,
the inner ear, to disruption in oxygen delivery or oxidative metabolism. Initial studies
with carbon monoxide showed that the ear is relatively well protected from this agent
due to the elevation in cochlear blood flow which accompanies carbon monoxide
exposure. Only transient auditory dysfunction as measured by a depression in the
cochlear action potential was observed. We report here on the results of more recent
studies in which rats were exposed to noise concurrently with carbon monoxide.
We anticipated that carbon monoxide might be able to potentiate permanent noise
induced threshold shifts and auditory injury because of evidence that noise may
serve to enhance cochlear metabolism and decrease cochlear blood flow. We
anticipated that concurrent carbon monoxide exposure would limit cochlear oxygen
delivery and predicted that a synergistic relationship would be found using combined
exposure. We have evaluated both the effects of carbon monoxide dose and of the
frequency characteristics of the noise upon auditory function across the rat's
audiogram. In these experiments auditory thresholds were assessed behaviorally using
reflex modification audiometry.
Combined Effects of Environmental Factors: Book of Abstracts ICCEF 1988
Rats were then assigned to groups which received noise alone (2 hours), carbon