1996 YANT AWARD LECTURE[1]
“THE HARMONIZED DEVELOPMENT OF
OCCUPATIONAL[2]
HYGIENE
- A NEED IN DEVELOPING
COUNTRIES”
Office
of Occupational Health
World
Health Organization
INTRODUCTION
First of all, I
would like to say how honoured I am to receive the 1996 William P. Yant
Award.
On this occasion I
must express my gratitude to all those who have inspired and helped me
throughout my career, from my graduate schools days at the University of Michigan,
under the guidance of the unforgettable Warren A. Cook, and later, at the
University of Pittsburgh, where Morton Corn shared with me years of knowledge
and experience - to my practice in Brazil, where support from Brazilian
occupational health pioneers, and also from NIOSH was invaluable. I still remember when a vertical elutriator
for our first byssinosis study in
I would like to
acknowledge the work of European colleagues who have given such an impulse to
our profession in this part of the world, as well as that of occupational
hygienists in developing countries, working usually under very difficult
conditions in a profession most often unknown.
I would also like to mention those occupational hygienists who believed
in international occupational hygiene and promoted the creation of the
International Occupational Hygiene Association.
I cannot name all the people who have influenced my work but I certainly
must thank them all because their enthusiasm and perseverance have helped me
throughout the years to keep my own enthusiasm and perseverance, as well as the
hope to see our profession universally recognized one day.
I would like to say
that the 1996 Yant Award also honours the World Health Organization, where I
have been working for the last 21 years, bringing the contribution of our
profession to the realization of one of the constitutional principles that led
to its creation:
“the enjoyment of the highest attainable
standard of health is one of the fundamental rights of every human being
without distinction of race, religion, political belief, economic or social
condition”.
OVERVIEW OF
OCCUPATIONAL HEALTH AND HYGIENE IN DEVELOPING COUNTRIES
In view of my
experience, I shall refer mainly to developing countries. However, in practically any country there are
regions of underdevelopment in occupational health and hygiene where hazards
that have been known for centuries still continue to cause new cases of preventable
diseases, one sad example being silicosis.
The Need for
Occupational Hygiene
Work is one of the
most powerful and rewarding forces in human life, indispensable for the
individual, for the community and for the development of nations. Unfortunately it can also be the source of
much suffering. As Pierre Hamp[3]
wrote: “We live on the suffering of
others. ... How many people earn their living pleasantly
? Many do so in unpleasant and often
intolerable conditions”.
As a matter of
social justice, human suffering related to work is unacceptable. I would like to quote what Ramazzini said,
about 300 years ago: “It is but a sad
profit which is achieved at the cost of the health of workers...”
Another aspect is
that harmful workplace agents and factors often result in appreciable financial
loss due to the burden on health and social security systems, to the negative
impact on production and to the associated environmental costs. People should not have to endure, and
countries cannot afford, such damaging effects.
According to the
World Bank “a burden of 36 million disability adjusted life years (DALY’s), or
3 percent of the global burden of disease is caused each year by preventable
injuries and deaths in high-risk occupations and by chronic illness stemming
from exposure to toxic chemicals, noise, stress, and physically debilitating
work patterns” (World Bank, 1993). In a
sample of industrialized countries, the International Labour Organization
estimated economic costs of occupational injuries and associated production
losses to be of the order of 1 to 4 % of the GNP; in developing countries this cost should be
much higher.
Many countries are
becoming industrialized and are undergoing rapid economic growth, often
disregarding, or not having the means to deal with, the steady increase in the
associated health and environmental problems.
It is important to
attain not only economic, but also social development. Workers should not pay with their health and
life for development, and neither should the environment be destroyed; it should be possible to ensure that the
present world population meets its needs for food, water, energy and shelter
without causing adverse effects on health and on the environment, and, without
depleting or damaging the global resource base, hence “without compromising the
ability of future generations to meet their own needs” (WCED, 1987). Unless measures are taken now, the situation
may become uncontrollable in the years to come.
Workers have a
right to a healthy and safe work environment, which is a realistic goal in view
of the knowledge and technology available today for the prevention and control
of hazardous agents in the workplace.
Occupational
hygiene is instrumental in ensuring this right;
furthermore, it also protects surrounding communities and the
environment, and contributes to safeguarding natural resources and improving
production, thus linking work, health, environment and development
aspects. It is therefore a key public
health profession, needed wherever there is a workplace.
Present Working
Conditions and Occupational Diseases in Developing Countries
In spite of all the
progress made, appalling working conditions, which were observed since ancient
times and impressed people like Plinius the Elder, Agricola, Ramazzini, and
later, Alice Hamilton at the turn of this century, are still shocking those of
us who have the opportunity to visit certain workplaces, on the eve of the
twenty-first century !
Although hazardous
exposure occurs everywhere, the situation is particularly serious in most of
the developing countries, where many people, including children, often work
under precarious conditions. Current
statistics do not reflect the global occurrence of occupational diseases and
impairment; however, there are studies
which demonstrate that they are appreciable problems.
In many developing
countries, the most prevalent diseases and impairments resulting from
occupational exposure include:
· pesticide
intoxications;
· lead poisoning;
· acute and chronic
solvent intoxications;
· silicosis and other
pneumoconiosis;
· hearing loss;
· diseases caused by
biological agents;
· diseases caused by
heat stress;
· musculoskeletal
disorders.
Studies correlating
sound exposure data with the associated health impairment are scarce,
particularly in developing countries.
However, the prevalence of health impairment among persons working under
very poor conditions is a good indicator of the situation; a few examples from published data are
provided here.
Uncontrolled
exposure to agricultural chemicals constitutes an appreciable occupational
health problem in developing countries, where a large proportion of the
economically active population is in agriculture, sometimes 80%, as in some African
countries.
In developing
countries, cases of pesticide poisoning demonstrated through clinical
investigations and biological monitoring, although often numerous, constitute
but a sample of the actual prevalence among exposed agricultural workers. Studies on pesticide poisoning and
cholinesterase inhibition, carried out among agricultural workers in
In Costa Rica, an
epidemiological study carried out between 1980 and 1986 showed that 3300
persons were hospitalized and 429 died (60 % of the deaths were due to
Paraquat); high risk groups for
occupational poisonings included agricultural workers in the age group 15-29
years, female workers and banana plantation workers (Wesselings et al., 1993).
Public health
workers engaged in vector control are another target group for pesticide
poisoning; for example, a very large
study carried out in Pakistan, involving 7500 field workers who sprayed a
Malathion[4]
formulation for malaria control, disclosed about 2800 cases of poisoning
(including 5 fatalities), which started
to occur soon after the beginning of the spraying programme (Baker, 1978).
Studies in
In the last 10
years, among 778 workers who had some respiratory complaint and were examined
in the outpatient clinic of the National Foundation for Occupational Health,
São Paulo, Brazil, 50.6% had a confirmed diagnosis of occupational lung
disease, asthma being the most frequent (about 31 %), followed by silicosis
(more than 10%) (Mendonça et al. 1994).
Concerning lead
exposure, a study on storage battery manufacturing, in India, reported air
concentrations around 37.5 mg/m3 and a 67% prevalence of lead poisoning (with
clinical symptoms) among the exposed workers (Durvasula, 1990).
A survey in
A study in a steel
mill in
In
Studies in
In developing
countries, overexposure to vegetable dusts and the resulting health impairment
are much more frequent than it seems, because this occurs among working
populations with little or no access to expert medical diagnosis. For example, a previously unknown disease -
the “rice millers’ syndrome” - was identified in
Biological agents
have not received sufficient attention from occupational hygienists because,
besides being more easily labelled as non-occupational, they are usually
considered of interest only among workers in rural areas and hospitals. It is true that such agents constitute a
serious problem in rural areas of developing countries; for example, a study in 38 districts in Ghana
demonstrated a strong correlation between schistosomiasis infection and
agricultural dams, since, in the worst affected areas, the prevalence in the
surrounding population, which was below 30% before the dams were built, jumped
to more than 70% (Hunter et al., 1993).
Yet, biological agents have a broader impact than sometimes believed as
they range from parasites affecting agricultural workers in developing
countries to spores and bacteria contaminating indoor air in sophisticated
offices.
Although ergonomic
factors usually draw more attention in industrialized countries, they also take
their toll in the developing world, with consequences such as musculoskeletal
disorders, particularly low back pain and impairment resulting from repetitive
motion, stress and fatigue. This is due
mainly to lack of adequate design and selection of equipment, indiscriminate
importation and use of ergonomically unsuitable machinery, and, lack of
adherence to the required work practices and schedules. For example, in
With
industrialization, adverse psychosocial factors and stress are also taking on
increasing importance as the social environment changes, and people suffer from
displacement from rural to urban industrialized areas, introduction to
unfamiliar machinery and equipment, separation from extended families,
crowding, city violence - all of which may become part of a worker’s daily life
influencing health and well being.
Isolated studies with small cohorts give
only a glimpse of what must be actually occurring among the global working
population, estimated by the ILO as 2.4 billion !
Occupational
diseases, which contribute significantly to increased morbidity and mortality,
particularly in developing countries, are very often under-diagnosed and
under-reported, or are diagnosed as non-occupational, thus constituting what is
often referred to as “the silent epidemic”.
In
Two published
examples from
As occupational
health and safety programmes are developed and reporting is improved, the
prevalence of occupational diseases usually shows an increase, although in
reality they must be decreasing due to some preventive action. For example, in Moroccan mines, for the
period from 1975-1990, there was a 100% increase in notified occupational
diseases (95 % being cases of silicosis), while there was a 70% decrease in
occupational accidents (which are rarely hidden as occupational diseases so often
are).
Particularly among
workers in rural areas, small industries and the informal sector, health
impairment is seldom linked to work.
Even when such workers have access to health care services, these are
rarely competent in occupational medicine, and, even if and when they are and
the link is established, very seldom is there adequate reporting of the findings to governments and, even less
frequently do they appear in the international literature.
Such occurrences
are only disclosed when a study is carried out with the purpose of
investigating the health status of a certain group of workers, or when a
certain type of recurring health impairment attracts particular attention. This was, for example, the case with 50
deaths from leukaemia and destruction of bone marrow, disclosed by the
haematology programme in Istanbul, Turkey, among workers who had been working
in the manufacture of shoes and hand bags, using a cheap glue with benzene as
its primary solvent, in small poorly ventilated shops and who had thus been
greatly overexposed to benzene (WHO, 1992a).
PROBLEMS WITH THE
PRACTICE OF OCCUPATIONAL HYGIENE IN DEVELOPING COUNTRIES
Countries have
reached varying stages of occupational health and occupational hygiene
development and practice, with different problems and different perceptions, so
that many scenarios can be observed at the same time on the international
scene.
Perception of
workers’ health problems
Decision makers and
even workers involved, often do not perceive clearly or accept the existing
occupational health problems and the importance of preventing hazardous
occupational exposure. Sometimes what is
lacking is the political will and motivation to apply or fight for the
application of available solutions.
The reasons are many; it is not only a question of awareness and
knowledge, but also of socio-economic and cultural aspects, which vary from
country to country.
One reason is that
the consequences of uncontrolled workplace hazards are seriously
under-estimated. Besides, other public
health problems may influence the perception of the importance of workers’
health within a framework of national priorities. Poor working conditions with no
controls; air, water and soil
pollution; hazardous waste disposal,
and, far away stratospheric ozone depletion, may easily fade into the
background when seen against pressing needs for water, food and shelter,
control of communicable diseases, and reduction of high infant mortality.
The worst scenario
though is when there is awareness of the problems but immediate economic gain
is placed higher than workers' health and environmental protection.
Perception of the
need for occupational hygiene
Yet another matter
is the perception of the need for action on the work environment to protect
workers’ health, that is, the essential role of occupational hygiene.
There are
situations when the concern for workers' health exists but is limited to
medical interventions. There are
occupational health services, which do not include occupational hygiene, and
where “prevention” relies solely on medical surveillance - including biological
monitoring, early detection, or diagnosis of occupational diseases. These may be indispensable adjuncts to
primary prevention, but can never replace it since they can only confirm
exposure or disease. “Early” is already
too late for the detection of such irreversible impairment as occupational
hearing loss, silicosis, and occupational cancer.
In the history of
occupational health, the shift from a purely medical approach to the
understanding that prevention should start at the workplace, in order to
eliminate or control hazards before health impairment occurs, marked the
beginning of occupational hygiene - that is, the change of focus from the “sick
worker” to the “sick environment”. This
shift, however, has not yet taken place in many parts of the world.
Furthermore, lack
of understanding of the professional ethics and commitment involved in the
practice of occupational hygiene, has generated suspicion, among workers, that
occupational hygienists may be biased towards the employers, and vice
versa.
Varying degrees of
resistance to occupational hygiene, on the part of other occupational health
and safety professional groups that feel threatened by a new profession, make
the situation even more difficult.
Another problem is
the belief, by some, that occupational hygienists are “people who measure”,
with the implication that what is done with the results is outside their scope
of action, that the interpretation of the obtained data should be left to the
biomedical personnel, and the control measures, to the safety and ventilation
engineers.
In some countries the only officially recognized occupational health
professions are occupational medicine and safety engineering. This has often been reflected in limited or
inadequate attention to the field of primary health hazard prevention in the
workplace. I once visited a large foundry
where considerable investment had been made in an exhaust ventilation system; when I asked about the frequency of routine
checks and maintenance (it looked as if it really needed it !), the plant physician told me “this is an engineering
problem so ask the safety engineer” and, when I did so, the safety engineer
replied that “airborne contaminants pose health hazards, so ask the
physician”. An outside engineering firm
had designed and installed the ventilation system, apparently with no concern
for its routine checking and maintenance, and never provided any follow-up. The distressing conclusion was that no one
felt really responsible; the company had
made an appreciable investment and the workers were given a sense of “clean
air” that might not be true !
Approaches to
occupational hygiene practice
Again,
it may happen that occupational hygiene services are established in a
governmental department or an institution, and are well equipped with excellent
instrumentation, but are unable to present, or orient towards effective
solutions to workplace problems, because the comprehensive approach to
occupational hygiene is lacking.
It is not unusual
to see more attention given to exposure assessment and monitoring than to
hazard prevention and control. The
fascination exerted by sophisticated equipment and by numbers is, for some
reason, greater than the interest in designing pragmatic solutions to prevent
exposure.
Even when hazard
prevention and control are on the programme of occupational hygiene services,
either at a governmental or workplace level, setbacks are often encountered,
for example:
·
control relying mostly on industrial ventilation and
personal protection (not always efficient), without due consideration to other
applicable measures, such as alternative technology, substitution of materials,
modification of processes, and good work practices;
·
preventive measures taken in an ad hoc manner,
rather than integrated into effective, carefully planned, well managed and
periodically evaluated programmes, and,
·
lack of anticipated preventive action, as well as of
coordination with environmental protection.
The comprehensive
approach to occupational hygiene, covering “anticipation, recognition,
evaluation and control”, must be promoted all over the world.
Even when all the
above aspects are understood and accepted, there may be a lack or shortage of
financial resources; the fact that I do
not go into this aspect does not mean that I underestimate its importance. I am focusing on those shortcomings which may
be overcome by knowledge, experience and collaboration among occupational
hygienists everywhere.
CONSIDERATION
OF SOLUTIONS IN PRESENT CONDITIONS
If the need for
occupational hygiene practice is to be met, there must be developments in
legislation, human resources and services, following appropriate and realistic
approaches.
Legislation
There is no doubt
that a legal framework is needed to ensure the protection of workers’
health. However, occupational health
legislation is a starting point; it has
no effect unless enforcement and control are ensured, through adequate
resources, staffing, programmes and services.
In many developing countries, legislation coverage constitutes another
problem as it does not always include agricultural workers, small enterprises,
and the informal sector.
Enforcement has
been a problem from the start; the first bill aiming at some control of working
conditions, in England - the “Health and Morals of Apprentices Act” of
1802, implied state intervention in private enterprise, but it did not alarm
employers “because the Act was totally ineffective as no proper system of
inspection or enforcement was provided.” (Luxon, 1984). The same statement could be made today in
many situations.
Even well meant
occupational health legislation may fail in ensuring effective protection of
workers’ health. One mistake that has
drawn my attention is the adoption of occupational exposure limit values as the
only instrument to enforce legislation to protect workers’ health, in
situations where there is no infra-structure of services to carry out the required
quantitative evaluations.
Whenever facilities
for sampling, analyzing, measuring, calibrating, are scarce or inexistent,
legislation which requires monitoring to prove compliance or non-compliance
with adopted occupational exposure limit values, may actually have a negative
rather than a positive effect on workers' health protection. It has happened that legislation allowed
employers to get away with not controlling hazardous exposure because enforcing
officers were materially unable to prove it quantitatively.
Lengthy and
expensive environmental or biological monitoring procedures may just not be
feasible in certain situations, and if feasible, may not be affordable,
particularly in developing countries.
Even when feasible
and affordable, monitoring capabilities may be better used in checking the
efficiency of control measures after their implementation (which is often
overlooked) rather than in confirming the obvious. There are laws in certain European countries
requiring that uncontrolled hazardous operations, such as electroplating and
sandblasting, be evaluated only after the required controls are installed, not
before; this should set an example
particularly for nations where the field of occupational hygiene is just
emerging.
“Recognition-evaluation-control”
may need to be changed to “recognition-control-evaluation”, when dealing with
obvious and serious hazards, and even to “recognition-control” if, in addition,
evaluation is not feasible.
In order to be
effective, legislation must take into account the circumstances in which it is
applied. Legislation in terms of “control
interventions” may often be more practical and cost-effective than legislation
relying solely on limit values. In fact,
controlling to the lowest feasible level is the safest principle.
The American
Conference of Governmental Occupational Hygienists (ACGIH), a world leader in
the establishment of acceptable exposure levels, has repeatedly stated that
their threshold limit values cannot be used to establish “fine lines between
safe and dangerous” (ACGIH, 1995).
Moreover:
·
values established for one country do not necessarily
protect workers in other countries where a number of aspects may differ
significantly, for example, socio-economic factors, duration of working week
and work schedules;
·
workplace exposure is usually combined; this is particularly relevant when there is
synergism or potentiation of effects, which are not yet fully accounted for,
among other limitations.
Nevertheless, a
simplistic approach of focusing solely on compliance or non-compliance with
these values has repeatedly been adopted in many developing countries, through
what I consider a “misuse” of the TLV’s.
Furthermore, there
are many uncertainties in the establishment and interpretation of occupational
exposure limits. There are also
uncertainties in the assessment of the exposures which actually occur in the
workplace.
The correct
appreciation of these uncertainties, the full understanding of their meaning,
and professional judgement in deciding on actions to be taken, are essential to
ensure that “the practice of industrial hygiene will be a science and an art
and not a mindless application of numbers and techniques”, as Morton Corn put
it so well in his Cummings Award Lecture ten years ago (Corn, 1986). This fundamental difference between a “person
who measures” and an occupational hygienist has not yet been fully understood
everywhere in the world.
The problem in many
developing countries is that, in the absence of competent persons able to pass
sound professional judgement, a solution is often sought by just “importing”
existing occupational exposure limit values, and considering that occupational
hygiene practice limits itself to measuring concentrations, or intensities, and
comparing the results with adopted tables.
In fact, it is difficult to define the borderline between problems
related to legislation and problems related to human resources. It is during the training of occupational
hygienists that more emphasis should be placed on “problem-solving” than on
“rule-following’.
Human resources
This is a key
issue. Unfortunately, the knowledge,
experience and professionalism required to practice occupational hygiene are
not yet universally available. In many
parts of the world, there is an acute shortage of competent professional
occupational hygienists and all efforts should be made to overcome this serious
shortcoming.
Some countries have
regulations requiring that the principles of occupational hygiene be applied to
the work environment, even if not officially recognizing the profession. These have been very adequately called, by
Burdorf, “occupational hygiene in disguise regulations”. If there are competent persons, the situation
may be kept under control; however, when
there are not, the result may be that the required tasks are performed by
persons who are not fully qualified, leading to voluntary or involuntary
“malpractice”. This may easily go
undetected, with disastrous results: no
effective protection of workers' health, lives endangered, and/or, unnecessary
expenditures of precious time and resources.
Legal instruments
for preventive interventions in the workplace must necessarily be accompanied
by the development of adequate professional competence. It is paradoxical to require by law the
performance of tasks which fall within occupational hygiene competence, while
ignoring the need for this profession.
Everyone knows what
a physician, an engineer, or a lawyer is.
Their training and practice may not be quite the same in different parts
of the world, but there is a fundamental understanding of these professions and
this, in addition to definite responsibilities, gives “recognition, influence
and opportunity[5]”
to all who practice them. This is not
yet true for occupational hygiene everywhere in the world.
In fact,
misconception still exists in relation to a well established profession as
occupational medicine. Many people think
that a doctor whose patients include workers is “an occupational physician”. Some years ago WHO sent to many countries a
questionnaire including a question on the number of available occupational
physicians; the official reply from one
developing country was 630, whereas an occupational physician working in that
same country replied 2 ! It is not
surprising that many are baffled as to what occupational hygiene really is
when, even in many developed countries, our profession is not yet fully
established and officially recognized.
Many of us are
fighting for international harmonization of concepts and requirements for
occupational hygiene training and practice;
why is this important ?
Regardless of
differing circumstances, it is indispensable to arrive at a universal
understanding of what occupational hygiene is and what the profile of an
occupational hygienist should be.
Besides, in
addition to knowledge, experience and a code of ethics, a profession requires
competence and quality assurance in the performance of its defined tasks and
responsibilities.
Quality means
credibility and it can only be universally assured for occupational hygiene, if
and when well defined and harmonized requirements are laid down and followed,
worldwide, for its training, including areas of knowledge, curricula and
training approaches, as well as for its practice, including the recognition of
competence. Accreditation of courses
and certification of professionals, even where not immediately feasible, should
be aimed at as a goal.
Only when such
requirements are met, we can expect to see occupational hygiene officially
recognized as a high level profession everywhere.
This does not mean
that occupational hygiene should be practiced in the same manner, in any
situation, regardless of local conditions - in fact, the “art” of adapting and
applying sound scientific and technical knowledge to each specific case is an
essential requirement of our profession.
Programmes and
services
The World Bank
(World Bank, 1993) estimates that “feasible interventions” in the work
environment could avert 36 million DALY’s per year ! (and this is based on reported
impairment). This is proof, if proof
were needed, that proper occupational hygiene programmes or services, both at
the national and workplace level are essential.
Many developing
countries lack services altogether, or approaches used in existing services are
inappropriate, or the utilization of resources is inefficient. However, if we share the wide experience
already available, both in successes and in failures, we can prevent repeated
errors. Shortage of funds is not the only problem; the proper use of even limited resources may
result in much better and more efficient services.
Multidisciplinary
approach and team work
The protection of
workers’ health and of the environment requires a multidisciplinary approach
involving occupational health, safety and environmental professionals; this includes occupational hygienists,
occupational physicians and nurses, ergonomists, work psychologists, safety and
environmental engineers. The harmonious balance
of a multidisciplinary approach, though difficult to achieve, should be
promoted worldwide.
Intersectoral
cooperation, interdisciplinary understanding, team-work and close collaboration
among all concerned professionals, are indispensable.
Although
occupational hygienists usually have to focus on specific technical issues,
they should not lose the perspective of global health and its
determinants. An integrated approach is
required to solve workers’ health problems, with due appreciation of public
health, socio-economic and other factors beyond the workplace.
On the other hand,
occupational health services should include or have access to occupational
hygiene expertise when envisaging preventive action, otherwise they may fail to
protect workers’ health, placing too much emphasis on the medical aspect and
overlooking indispensable primary prevention.
Alternative
approaches
In certain
developing countries, classical and comprehensive occupational health and
hygiene services cannot be provided everywhere and at all levels.
Occupational
hygiene in particular is often assumed to be “too sophisticated” a field,
applicable only if considerable material means, such as modern equipment and
laboratories, are available. However,
this is not necessarily so. Rather than
leaving large sectors of the working population completely without the benefits
of occupational hygiene, means should be sought to optimize resources and
broaden the scope of action of the often very few existing occupational
hygienists.
The “primary health
care[6]”
approach, adopted by WHO and many of its Members States facing a multiplicity
of health problems with limited resources, may be used as a source of
inspiration.
If properly planned
and applied, under the supervision of experienced occupational hygienists, a
“primary health care” approach to occupational hygiene might help countless
workers all over the world. It would
involve appropriate simple methodology and training of those who form the
“first line contact” with working conditions (e.g., the workers themselves,
supervisors, community health workers, people in health care centres) to:
·
recognize obvious hazards and dangerous work
practices;
·
identify and localize conspicuous hazard sources;
·
recommend simple control measures;
·
recognize conditions which offer immediate danger, or
are somehow suspicious and seem to require further study, and report on them to
the next level of competence, for example, in a governmental department.
This would require
simple but very well designed check-lists.
When working conditions are very bad, lives may even be saved by people
having elementary knowledge, such as:
which chemicals can penetrate through the skin; which conditions may lead to the accidental
formation of toxic agents, or, which work practices are particularly
dangerous. Nevertheless, efficient lines
of communication with fully qualified occupational hygienists are essential.
Common mistakes in
the establishment of programmes
The acknowledgement
of a problem is the first step towards its solution, therefore in order to
improve existing occupational hygiene programmes and services, and to avoid
mistakes when establishing new ones, it is important to look at some of the
shortcomings which are often encountered, particularly in developing countries:
·
planning
Lack of planning
has jeopardized many a programme. In
order to ensure that objectives are adequately established and efficiently
achieved, making the best use of the available resources, elements such as the
nature and magnitude of prevailing hazards, characteristics of the working
populations to be served, legal requirements, existing infrastructure and
support services, should be the object of preliminary analysis.
Planning should
also include the definition of an organizational structure, profile of the
required human resources and plans for their development (if needed), assignment of responsibilities,
provisions for facilities, equipment, operational requirements, communications
and information, as well as for periodical and critical evaluation aiming at
continuous improvement.
·
equipment
Mistakes over
equipment are a recurrent problem in developing countries and may result from
purchasing before the real needs have been established, before the required
skills for operation, maintenance and repairs have been developed, and/or
before competence to carry out all steps of each procedure (e.g., sampling and
analysis, including calibration) has been ensured.
·
allocation of resources
Unwise allocation
may be more of a problem than lack of resources. Amazing discrepancies may often be observed
in the importance given to different steps of even the same procedure and hence
in the allocated resources.
It is not unusual
to encounter situations where qualified chemists, in “state of the art” analytical
laboratories, are analyzing samples which were collected with poorly calibrated
equipment, or, to realize that samples which were collected with excellent
equipment are not at all representative of workers’ exposure because an adequate
sampling strategy was not followed. The
old saying “no chain is stronger than its weakest link” should be more often
recalled.
Another shortcoming
which has caused the blockage of many a service, particularly in developing
countries, is the underestimation of operational costs. This does not refer only to material
aspects, such as expendable supplies, spare parts, transport (vehicles, fuel,
maintenance) and travel, but also to matters such as information update and
maintenance of staff competence.
·
communications
Ineffective means
of communication have often jeopardized the efficiency of team work and the
feasibility of intersectoral collaboration.
Continued exchange
of information and joint efforts among occupational hygienists and other occupational
health, environmental and related professionals, are key to solve workplace
problems, together with broader issues such as environmental protection and
health promotion.
·
information
Some years ago it
could be said that, in terms of telecommunications, what applies to
industrialized countries could not possibly apply to the rest of the
world; however, in recent years many
developing countries have increased their telecommunications capabilities at a remarkable
rate. As improved means of communication
reach even the remotest areas in the world, access to up-to-date information
becomes increasingly feasible.
Rather than saying
“developing countries cannot afford the price of information links”, the
reasoning should be “developing countries cannot afford not to have
access to information links”. The most expensive
information is that which is not where it is needed, when it is needed, particularly
“life-saving” information.
A mistake often
made in developing countries is to give low priority to information technology
in connection with occupational health and hygiene programmes. At the early stages of development of such
programmes, or services, it might be even more helpful to have ready access to
up-to-date, relevant information on toxicology, risk assessment, recognition
and prevention of hazards, than to have expensive sampling and analytical
equipment. Personal computers, CD-ROM
readers and access to the Internet become more and more usual and should be
envisaged for occupational hygiene services, all over the world.
On-line networked
services provide an ever-increasing amount of information relevant to workers'
health and environmental protection.
Moreover, communication through electronic mail facilitates discussions
and exchanges of experiences among occupational hygienists everywhere. Information which is mostly accessible to the
scientific community can thus be given much wider dissemination; its benefits can be extended from the
laboratories and research institutes to the real world, helping to
bridge the “knowledge-application gap” and to decrease inequalities between
countries. This may be even more
important than generating new theoretical knowledge.
·
managerial shortcomings
Poor executive
management may be a serious hindrance to the development of efficient
programmes and services. Managerial
skills which are indispensable for competent leadership include ability to:
· make decisions as to goals to be reached and
actions required;
· inspire team work, with full participation of
all concerned;
· remove obstacles to the completion of the
required tasks;
· establish realistic time-tables, according to
priorities and available resources, since the implementation of successful
programmes is a gradual process.
Programme managers
should be able to distinguish between what is impressive and what is important; detailed quantitative evaluations are
very impressive, but more important are the decisions and actions
taken thereafter.
·
health and safety of the staff
This has been the
source of many problems; occupational
hygienists and their assistants are not always appropriately protected against
the often serious hazards to which they may be exposed in field surveys and in
laboratories.
In certain parts of
the world, endemic tropical diseases, such as malaria, and other public health
problems should be borne in mind, particularly at a time when there is so much
movement of professionals throughout the world.
Depending on the type of work, provisions, such as immunization or even
antidote for snake bites, may be required.
Quality assurance
Quality of the
profession
The competence of
those in charge of controlling workplace exposure is crucial as people's health
and lives are often at stake.
Accreditation of courses and certification of professionals are critical
to ensure acceptable standards of occupational hygiene competence and practice.
The International
Occupational Hygiene Association promoted a survey of existing national
certification[7]
schemes, already published (Burdorf, 1995) together with recommendations for
the promotion of international cooperation in assuring the quality of
professional occupational hygienists, which include the following:
·
the harmonization of standards on the competence and
practice of professional occupational hygienists;
·
the establishment of an international body of peers to
review the quality of existing certification schemes.
Other suggestions
in this report include items such as:
“reciprocity”, and “cross-acceptance of national designations,
ultimately aiming at an umbrella scheme with one internationally accepted
designation”.
Quality of the
procedures
“Work done” is not
necessarily “work well done”; all
occupational hygiene procedures should be correctly carried out, which requires
a systematic approach to quality control.
The concept of “quality
assurance” relates primarily to activities which involve measurements. Whenever sampling and analytical procedures
are required for exposure assessment, both should be considered as a single
procedure from the point of view of quality assurance. Sources of errors should be found and the
errors corrected. Both internal quality
control and external quality assessments, or proficiency testing, should be
applied in occupational hygiene laboratories.
Laboratory accreditation is a very important control tool and should be
promoted.
Although not yet
applicable in many parts of the world, the establishment of quality assurance
schemes should be regarded as a goal to be eventually reached, so that all
occupational hygiene services may gradually develop in the right
direction.
It is paradoxical
to consider that, in a certain developing country, it is too premature to
enforce quality assurance requirements and, at the same time, adopt legislation
based on compliance with occupational exposure limit values. If one is not feasible, the other is not
acceptable, since to rely on evaluation results without having a sufficient
degree of confidence in their reliability not only may be misleading but also
generates unnecessary expenses.
Quality management
systems
International
standards for quality management systems are being increasingly followed
worldwide, including in many developing countries, to manage quality aspects of
products and services, in the most effective way. Similar standards for environmental
management are being finalized.
Corresponding
standards applied to occupational health and safety, hence also to occupational
hygiene, would serve all countries, either in the immediate context or as
models to guide progress in this field towards the right goals.
However, while
management systems related to products concentrate on the consistency of
production, equivalent systems for occupational health and safety should also
ensure the appropriateness and quality of the end product. In this case it is not only a matter of
consistent management, but consistent management to achieve relevant and
worthwhile goals. A system that would
ensure only managerial consistency would be equivalent to a measuring
instrument which is very precise but whose “zero setting” is off, and which
therefore systematically gives inaccurate results.
The competence of
all involved in applying and verifying any standard is vital.
Related Issues
Public Health
An understanding of
public health is important, particularly when factors outside the workplace
constitute significant health determinants and add to occupational hazards,
which is frequently the case in developing countries.
Not only there are
conditions which affect the workers' health status, thus aggravating the
adverse effect of occupational exposures, but there may be interaction between
workplace hazards and the surrounding communities. This is particularly true of the informal
sector (“cottage industries”) and agricultural work, where it is not unusual
for the working and living environment to be the same. For example, people have been even fatally
poisoned when, through ignorance or negligence, containers which had previously
contained toxic materials were used for water and food.
In urban areas,
hazards may easily spread from the workplace;
appreciable lead exposure of workers and their neighbouring communities
has been demonstrated in connection with informal small enterprises recycling
lead-acid batteries (Matte, 1989).
Industrialization
and Import of Hazards
New techniques for
faster production usually generate more hazardous agents, if not accompanied by
the required controls. A classical
example is what happened in the granite quarries in
This example is
mentioned because similar occurrences are frequent now in many developing
countries. Modern techniques and
high-speed machinery and equipment, such as drills, crushers, electric saws,
are introduced (often in replacement of traditional slow processes) without the
required health and safety protective measures, thus leading to increased
hazardous exposure.
Industrialization
has often been linked with export/import of hazards in ways that include the
following:
·
processes, machinery and equipment no longer
acceptable in a certain industrialized country,
from the point of view of health, safety and environmental protection, are
exported to developing countries where regulations are less strict, or poorly
enforced;
·
machinery is
exported without the required controls;
·
modern machines and equipment are exported but the required
know-how for their correct operation is not ensured, with the result
that unskilled workers utilize them without proper training, hence unsafely.
A related issue,
which constitutes a serious global problem, is the transboundary movement of
hazardous products and wastes, particularly damaging when dealing with highly
toxic waste and when the receiving country is neither fully aware of the extent
of the hazard nor competent to adequately handle it. In this connection, it should be mentioned
that the OECD[8]
nations, with about 15% of the world's population, are responsible for the
production of almost 80% of all hazardous industrial waste.
Environmental
Health
Environmental
pollution is definitely interlinked with workplace agents and the adequacy of
occupational hazard prevention and control programmes. Harmful chemicals which are eliminated from a
work process, will neither affect the workers, nor pollute the environment. Moreover, many control systems, based on
product re-cycling, protect not only the workers, but also the environment and
the natural resource base, thus contributing to a safe and sustainable
development.
Environmental
disasters and other tragic events have occurred as a result of inappropriate,
or non-existent, control strategies and emergency procedures in the workplace,
as well as of inadequate disposal of hazardous wastes in community garbage
dumps or normal sewage systems. Actions
in the workplace not only impact on the immediate vicinity but also much
farther; important transboundary
environmental problems generated or aggravated by work processes include
long-range transport of air pollutants, damage to the stratospheric ozone layer
and the “green-house” effect.
As an outcome of
the United Nations Conference on Environment and Development (UNCED) held in
Rio de Janeiro, Brazil, in June 1992, the “Agenda 21” was prepared
hopefully to ensure the protection of our health and our planet throughout the
21st century (UNEP, 1993), through local and global action. The Agenda recognizes the important role of
occupational hygiene, as demonstrated in recommendations such as the following:
“... establish
industrial hygiene programmes in all major industries for the surveillance of workers' exposure to health hazards
...”
“... emphasize
preventive strategies to reduce occupationally derived diseases ...”
INTERNATIONAL
COLLABORATION
International
collaboration may be instrumental in developing or strengthening national
capabilities to recognize and solve occupational health problems. Sharing of knowledge and experience also
contributes to avoiding duplication of efforts and wasting valuable
resources.
International
collaboration has led to many achievements in the health field, one successful
example being the eradication of smallpox from the world and the eradication of
polio in certain regions.
International
Organizations
Many United Nations
specialized agencies have activities related to workers’ health and the
environment, for example, the World Health Organization (WHO), the
International Labour Organization (ILO), the United Nations Environment
Programme (UNEP) and the United Nations Industrial Development Organization
(UNIDO). Such activities include the
preparation of scientific documents, recommendations, manuals and guidelines,
as well as technical cooperation.
As to WHO, in order
to achieve its ideals, all factors which impact negatively on health must be
controlled, and those which impact positively must be enhanced. Among WHO’s functions, some are included
which relate directly to occupational hygiene, for example: “to promote, ....
the improvement of nutrition, housing, sanitation, ..., working conditions and
other aspects of environmental hygiene”.
The WHO
Occupational Health Programme has therefore an occupational hygiene component,
aiming at:
·
the development of occupational hygiene worldwide, at
a high level of professional competence, and as an integral part of
occupational health multidisciplinary programmes;
·
the worldwide adoption of adequate methodologies for
the recognition of occupational hazards and for exposure assessment in the
workplace;
·
the worldwide promotion of hazard prevention and
control in the work environment, through appropriate technologies, also
accounting for environmental protection and sustainable development;
·
the promotion of international collaboration and the
sharing of technical and scientific knowledge on occupational hygiene, among
countries around the world, with a view to decreasing the often wide
inequalities in this field.
WHO collaborates
closely with other relevant international organizations, as well as with a
number of international and national professional associations, including the
International Occupational Hygiene Association (IOHA) and the International
Commission on Occupational Health (ICOH) - which are Non-Governmental
Organizations in Official Relations with WHO, as well as with the American
Industrial Hygiene Association,
Examples of
International Collaborative Action in Occupational Health
Global Strategy on
Occupational Health for All (WHO, 1995a)
An important
international effort was the recent development of the “Global Strategy on
Occupational Health for All”, through the WHO Network of Collaborating Centres
in Occupational Health, comprising 52 institutions in 35 countries around the
world (WHO, 1995b). The purposes of the
Strategy are:
·
to identify the main needs and establish priorities
for action at the country and global levels, and,
·
to trigger the necessary awareness and political
commitment to develop appropriate occupational health services, through
intersectoral coordination and international collaboration.
This Strategy is in
line with WHO’s constitutional function of directing and coordinating
international efforts in the health field, and was based on certain fundamental
principles which include the following:
“occupational health and safety is an
integral component of the health concept, which is part of socio-economic
development”.
The recommended key
principles for international and national occupational health policies are:
§
avoidance of hazards (primary prevention)
§
safe technology
§
optimization of working conditions
§
integration of production with health and safety
activities
§
government's responsibility, authority and competence
in the development and control of working conditions
§
primary responsibility of the employer and
entrepreneur for health and safety at the workplace
§
recognition of workers’ own interest in occupational
health and safety
§
cooperation and collaboration on an equal basis by
employers and workers
§
right to participate in decisions concerning one's own
work
§
right to know and principle of transparency
§
continuous follow-up and development of occupational
health and safety
The contribution of occupational hygiene
is of particular importance for the achievement of the four first
principles. It is expected that a
worldwide response will contribute to the implementation of this Strategy.
Silicosis Control
and Elimination
Silicosis, whose aetiology has been known
for centuries, is a perfectly preventable disease.
Nevertheless,
millions of workers, mostly but not exclusively in developing countries, are
exposed to airborne dust containing free crystalline silica, and, even though
there is much under-reporting, a very high number of silicosis cases are still
known to occur throughout the world.
Examples from developing countries were previously presented, but this
problem affects also industrialized countries.
For example, in the
In order to
surmount this situation, it was decided, during the Joint ILO/WHO Committee on
Occupational Health at its 12th Session, in April 1995, to develop a
joint programme aiming at the global reduction and eventual elimination of
silicosis.
In accordance with
the WHO Global Strategy on Occupational Health for All, due emphasis will be
given to the “key principle of primary prevention”, by promoting and supporting
the development of national capabilities in the field of prevention and control
of dust exposure in the work environment.
As Alice Hamilton said: “...obviously, the way to attack silicosis is to
prevent the formation and escape of dust ...”.
International
Collaborative Action Specifically in Occupational Hygiene
Consider the
following examples of international collaborative action involving occupational
hygienists and other scientists, from different agencies, institutions and
associations, in different parts of the world, who have worked together so
that, based on their individual experience, a consensus could be reached on the
best approaches, guidelines and advice on specific matters.
Development of
Human Resources
It is of utmost
importance to extend the benefits of appropriate occupational hygiene training
worldwide. International meetings,
workshops and training activities provide a unique forum for fruitful discussions
in this field.
The preparation of
educational materials, reflecting experiences from around the world, greatly
contributes to the wide dissemination of available knowledge thus enhancing the
development of adequate human resources.
The Conference on
“Training and Education in Occupational Hygiene: an International Perspective”,
held in Luxembourg, 1986, as a joint activity by the European Commission, WHO and ACGIH, stimulated much thought about
the need for international collaboration in this field. At that time the International Occupational
Hygiene Association (IOHA) was only a dream in the minds of those committed to
have our profession developed and strengthened worldwide.
In 1987, IOHA was founded and one of its first
activities was to hold, jointly with WHO, a workshop on “Occupational Hygiene
Training”, which took place in
A significant
landmark in the consistent development of occupational hygiene worldwide was
the meeting held in WHO, Geneva, in 1991, jointly with EURO/WHO and with
collaboration from the European Commission and IOHA. The outcome of this meeting was the
publication “Occupational Hygiene in
International
collaboration for the development of human resources continues as efforts to
promote consistent occupational hygiene training, at a high level, are kept up
in different parts of the world.
Collaborative activities in this respect are being started in
Project on “Hazard
Prevention and Control in the Work Environment - Prevention and Control
Exchange (PACE)”
At this point I
would like to quote a Zen proverb:
“Knowing and not applying is the same as not knowing”.
The vast knowledge
on occupational hazards and their prevention is not yet fully applied; an unacceptable number of occupational
diseases still occur everyday. Lead
poisoning and silicosis, for example, have been known for centuries; nevertheless, exposure to their etiologic
agents remains uncontrolled in countless workplaces throughout the world, still
providing “text book” cases of perfectly preventable diseases.
The WHO Office of
Occupational Health launched the “Prevention and Control Exchange (PACE) Programme”,
at an international meeting, held in WHO, Geneva, September 1994, involving
occupational hygienists from different parts of the world, with the following
main objectives:
·
to promote awareness and political will concerning the
need for prevention and control as a priority element of occupational health
programmes, and,
·
to strengthen, at the country level, technical and
managerial capabilities for the utilization of successful approaches to the
prevention and control of health hazards in the workplace, integrated into
adequate programmes, emphasizing anticipated preventive action and
environmental protection.
An advocacy
document - “Prevention and Control Exchange (PACE) - a document for
decision-makers” (WHO, 1995c) - was prepared and widely distributed around the
world. Its intended readership includes
persons in a position to influence national legislation and enforcement, as
well as those who can promote and contribute to effective primary prevention at
the workplace level, particularly occupational health professionals, managers,
production engineers, supervisors and workers.
Furthermore,
articles about PACE have been published in Australia, Brazil, France, Germany,
The Netherlands, Poland, Sweden, Thailand, UK and the USA (Swuste et al.,
1995), thus giving wide dissemination to the PACE initiative.
Other PACE
activities include:
t
the exchange and
dissemination of existing knowledge and information on the prevention and
control of occupational hazards;
For this, the
following material is under preparation:
“PACE - Directory
of Resources in the Field of Hazard Prevention and Control in the Work
Environment” which includes information on published material, competent
institutions and agencies, CD-ROM’s and other databases, including on Cleaner
Production, and relevant Internet Resources;
this Directory will also be disseminated via the Internet.
“PACE - Case
Studies on Control Solutions for Small-scale Industries”, for the dissemination
of practical approaches to the control of workplace hazards, particularly
applicable to small enterprises, and, for the promotion of applied research in
this field.
t
support to the
development of the required human resources.
For this, an
educational module - “PACE - Hazard Prevention and Control in the Work
Environment: Airborne Contaminants” - is
envisaged. This module, comprising a
manual and training videos, will present innovative approaches and reflect
international experience on the subject.
There has also been collaboration with actual training activities in
different countries.
Project on
“Reference Method and Quality Assurance Schemes in the Evaluation of Exposure to Airborne Fibres in the
Workplace”
Whenever evaluating
occupational hazards, the wrong decision can cost in terms of workers' health,
if there is under-estimation of the hazard, or in terms of unnecessary expense
of resources, in the case of over-estimation.
Although it does not replace primary prevention, the evaluation of airborne
fibres in the workplace is needed for exposure assessment and for testing the
efficiency of control measures.
Harmonization of methodology is important to permit comparison of
results and inter-laboratory collaboration, and eventually to permit the establishment
of international quality assurance schemes.
Therefore WHO, with collaboration from other international and national
agencies and institutions, carried out a project, whose result is the
publication “Determination of Airborne Fibre Number Concentrations - a
Recommended Method, by Phase Contrast Optical Microscopy (Membrane Filter
Method)”. The next step will be the
promotion and hopefully the implementation of an international proficiency
testing scheme.
Conclusion
Looking at the
world at large, one can observe the whole history of occupational health and
occupational hygiene happening at the same time. In the past, each step, each achievement,
took a long time, sometimes decades, sometimes centuries ! The great difference, at present, is that
these steps can now be conquered at a much faster rate, because the barriers of
ignorance are being increasingly replaced by bridges which can be more easily
crossed. How fast these bridges will be
crossed depends largely on us because passwords for crossing them include
sharing and collaboration among occupational hygienists everywhere.
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[1] Presented on 21 May 1996, at the American
Industrial Hygiene Conference and
Exposition,
[2]
The term “occupational hygiene” is used throughout
this lecture rather than its
[3] Pierre Hamp (1876-1962), French writer,
particularly concerned with industrial life and injust working conditions.
[4] Partially
converted to iso-Malathion as result of inadequate production and storage.
[5] “Recognition, Influence and
(American
Industrial Hygiene Conference and Exposition)
[6]“Primary health
care” is based on practical, scientifically sound and socially acceptable
methods and technology, made universally accessible to individuals and families
in the community, through their full participation, and at a cost that the
community and country can afford to maintain, at every stage of their
development, in a spirit of self-reliance and self- determination.
[7]
understood as “a formal scheme based on procedures
for establishing and maintaining knowledge, skills and competence of professionals”
(Burdorf, 1995)
[8] OECD =
Organization for Economic Cooperation and Development