2004 Jeffrey S. Lee Lecture


AIHCE 2004, Atlanta, 10 May 2004


A Realistic Approach to Occupational Hygiene

Berenice I. F. Goelzer


Why a realistic approach? Occupational hygiene methodology and primary prevention philosophy are needed in more places than we presently reach. The tremendous worldwide need for occupational hygiene is undeniable, as it has an impact, not only on workers’ health, but also on environmental protection, sustainable development and decent globalization. Therefore, it should be applied in every place where work is performed – be it a factory, a farm, a hospital, a mine, a construction site, a backyard, a super market, a hairdresser salon, a travel agency, an office or a home. And for this, we need to be more realistic.


If occupational hygiene is well applied, it will avoid human suffering, save lives, contribute to protecting the environment; it will also bring economic benefits to individuals, to society and to nations. Besides the human aspect, which has no price, health impairment and disease caused by work have a tremendous cost. The ILO estimates that the cost of occupational diseases and accidents in developing countries may reach 10% of the GNP (studies in developed countries, such as the UK, the USA and some Nordic countries have revealed that such costs are of the order of 2-4% of the GNP). Therefore, occupational health and safety – of which occupational hygiene is an indispensable component – can contribute to an economic, social and sustainable development.


Development is good – one has just to compare health parameters in developing and developed regions of the world. Work is a positive force; just as an example, I would like to mention a recent survey among young people in Brazil, where 95% replied that “happiness means to have a good job”. The beauty of our profession is that it aims at ensuring that workers be spared the negative aspects of work so that the positive aspects may be fully enjoyed.


Occupational hygienists have an understanding of occupational risk factors and knowledge to prevent most of their undesirable outcomes. And, knowledge implies responsibility to fight for its application – where it is needed, when it is needed and in a form that can be used by those needing it. For this, we have to face new challenges and may have (in some cases) to adapt many of the classical (and often so comfortable!) concepts and methods to make them applicable and useful in all kinds of situations.


The world of work is changing and our profession must follow, if it is to adequately respond to its needs. I will now present some changes, which – in my opinion – are still needed.

1. Broadening the Scope of Action and of Thinking

(Concerning occupational risk factors, occupational settings and the social dimensions of production and trade)


1.1 Occupational risk factors and their outcomes


Occupational risk factors are a concern at work and beyond, as they outreach to the general environment up to the stratosphere.


According to the World Health Organization, “health is a state of physical, mental and social well-being”. Therefore, in order to fully protect workers’ health, any occupational risk factor in the workplace must be identified and either avoided or controlled, so that its potential to cause harm will not materialize. Risk factors can be of different natures and none should be ignored – in fact, they often interact in causing harm to human health. Let’s just briefly review them:


Chemical Agents and Dusts


Among problems, which are new or changing, we can mention new chemicals, new knowledge on the toxicological properties of known ones; accidental formation of chemicals, which appear where never before (e.g., due to a change in process).


Along with classical concerns such as intoxications, irritation, asphyxia and pneumoconioses (known for centuries), some outcomes have been brought to the fore in recent years, such as, for example, sensitization and allergies (skin, rhinitis, allergic alveolitis, asthma). One example is latex sensitivity, resulting from allergy to natural rubber latex proteins, which has caused so many problems among people who have to wear latex gloves.


Occupational asthma has been a growing concern – people are responding to lower and lower concentrations of the triggering agents – and this affects from farmers, industrial workers, hospital workers, carpenters, bakers, hairdressers, to household workers. For example, in France, according to the National Occupational Asthma Observatory, over 500 new cases of occupational asthma have been registered every year in recent years. In order to point out the complexity of the problem (and the challenge to occupational hygienists !), it should be mentioned that about 300 organic and inorganic agents (both sensitizing and non-sensitizing) have been associated with occupational asthma, for example, isocyanates, organic dusts (such as flour and certain wood dusts), animal proteins (from rat and cat urine), terpenes, biological enzymes, metal salts (e.g., platinum salts, nickel), certain paints, adhesives and plastics, just to mention a few.

Other outcomes that have been causing growing concern (even when in places where, for example, intoxications and asphyxia are well under control) include occupational cancer, reproductive effects and effects by endocrine disruptors.

Physical Agents

Although pretty well known, there are new concerns. For example, it is time to worry more about the non-auditory effects of noise (as we know, most standards and action aim at avoiding noise-induced hearing loss only) and electromagnetic fields.

Biological and vegetable hazards

In this respect, there are many new concern such as: viruses, which cause HIV, Hepatitis B and C, Flavoviruses (this one the etiological agent of dengue and yellow fever, whose vector, Aedes Aegipti, had been eradicated in Brazil but crept back due to slackening of public health measures in some other place, thus showing that this is one world); anthrax bacillus (previously known to be a danger only to cattle and cattle products handlers and which now may threaten postal workers, victims of terrorism); Legionella pneumophila (breeding in humidifiers and transported by air conditioning systems).

In fact, these 3 groups of agents (chemical, physical, biological) combine to cause what has been called “sick building syndrome” and the area of “Indoor Air” has become a concern for occupational hygienists.

Ergonomic factors

This group of factors, which has taken increased importance in the modern world, includes excessive static and dynamic loads resulting from, for example, inadequate weight lifting, bad posture, overexertion and repetitive movements. The outcomes include a wide range of musculoskeletal disorders (MSDs). Occupational hygienists will not replace ergonomists but cannot ignore this important group of risk factors and must act as the front-line contact with them, identifying and solving obvious problems and having the capability to recognize situations when more specialized expertise is required (as a GP physician does, when recognizing diseases which require referral to a specialist).

One important group of MSDs is that of Repetitive Motion Disorders (RMDs), such as carpal tunnel syndrome, tendonitis, tenosynovitis, bursitis, and epicondylitis, which may cause temporary or even irreversible damage. RMDs usually affect workers performing repetitive tasks at, for example: assembly lines, cash registers, personal computers and other visual display units, meatpacking plants, sewing machines, laboratories (e.g., repeatedly working with manual pipettes), carpentry, gardening and playing musical instruments.


Just to illustrate the importance of work-related musculoskeletal disorders, it can be mentioned that, according to the European Agency for Safety and Health at Work, these diseases constitute one of the most prevalent occupational health problems, affecting millions of European workers in all occupational sectors, costing much in human suffering and also representing a sizeable financial burden. A Eurostat study indicated that MSDs are among the 10 most frequent diseases in the EU.


Some examples from the European Agency 2000 Report on the social and economic costs of musculoskeletal disorders for EU Member States:


  • in Germany, MSDs account for almost 30 % of all workdays lost due to sickness, with an immense financial cost of the order of billions of Euros;

  • in the Netherlands, MSDs account for about 46% of all work-related sickness leave;

  • in the UK, almost 10 million working days are lost each year due to work-related musculoskeletal disorders.


In the USA, it is estimated that work-related musculoskeletal disorders (MSDs), only of the upper extremities, cost more than US$ 2.1 billion, and that low-back disorders cost about US$ 11 billion in workers’ compensation, each year.

Psychosocial Factors

Psychological problems, socio-economic pressure, bad working relations, harassment and mobbing, too much or too little responsibility, lack of control over one’s work, under or over qualification, double load (work/home) – all these constitute another group of occupational risk factors, which represent a growing concern. These factors lead to occupational stress whose consequences range from varying degrees of depression to psychosomatic manifestations (e.g., gastrointestinal, cardio-vascular), and may explode into violence (at work, in the community or at home). As an illustration, it is estimated that, in the European Union, more than 25% of workers have some problems of work-related stress. Studies in the USA, by universities and insurance companies, have shown similar and even higher figures.

The World Health Organization, in its 2002 World Health Report, analyzed outcomes of selected occupational risk factors, from all these groups, for example: work-related carcinogens, selected airborne particulates, ergonomic stressors, noise, and risk factors for injuries (including injuries with contaminated sharps leading to HIV and Hepatitis C infection).

Moreover, there are many other health determinants, which affect health, interact with occupational exposure, and which can be controlled (at least partially) through actions in the workplace such as, for example, anti-smoking campaigns, alcohol and drug abuse control, promotion of healthy behaviour and healthy lifestyles.


It should be kept in mind that hazardous agents go beyond the workplace, not only as effluents and waste, but also through means of transportation (transport of dangerous goods) and as consumer goods (use, final disposal). One has to think beyond the workplace, therefore a holistic approach to workers’ health and the environment is necessary.

  1. Occupational Settings


The world of work is continually changing and occupational hygiene practice has to adapt to these changes, “longitudinally” (in a same country, as the nature of work evolves) and “transversally” (when a professional goes to practice in another part of the world where the nature of work is different).


In developed countries, there has been a shift from agriculture to extraction and manufacturing, to services (where the majority of workers are today), including outsourced services (many people work from their homes). Patterns vary; in certain countries only about 2-3% of the workforce is in agriculture (even less), while in others, this percentage is around 70-80%.

In many developing countries, there are many problems related to small enterprises, informal work and home industries, as well as outsourcing. Unemployment drives people to create work at home, e.g.: reclaiming lead from old batteries, extracting gold by amalgamation with mercury, making handcrafts (sometimes in leather, using toxic glues); cooking food to sell (often using poor fossil fuels or biomass in unventilated rooms – the problem is not only carbon monoxide: studies have linked higher incidence of lung cancer to PAH exposure in such home situations).

I would like to mention some problems with outsourcing, particularly in developing countries. One of them is that occupational health and safety measures, education and inspection are more often than not unavailable for outsourced work. Another problem that is happening, in a country I know: factories that are downsizing dismiss their workers and, as a “parting gift”, give them their machine (often obsolete and hazardous) so that they may work at home; then they outsource to these workers hazardous tasks, which often involve toxic materials (as is the case, for example, of the leather goods industry). Needless to say, that families, including children, are thus exposed while the factory itself is “clean” and passes all inspections.

In situations when the boundaries between work and living environment are “hazy” or non-existent and serious hazards are present, the establishment of “exposure-effect” is even more difficult.

As occupational hygienists, what can we do? Of course, we cannot inspect homes nor expect that people working in these sectors would seek our professional advice. Nevertheless, we can and must think on ways and means to reach such workplaces, and give more attention to topics such as:

  • research on alternative less hazardous processes and materials

  • effective risk communication to the general public

  • mechanisms to raise awareness and motivation among decision-makers on the need for actions such as banning, restricting or controlling sales of toxic chemicals, adoption of adequate labeling, establishment of compulsory training for buyers of pesticides, etc.

  • work practices

  • education and training, at different levels

  • the impact of the informal sector and home work on health and on the environment, in order to raise awareness concerning these problems.

  1. Social Dimensions of Production and Trade

Here we should consider the issue of globalization and some related unfair situations, which occur, for example, when (in order to spend less) certain industries move to places where occupational safety and health, as well as environmental regulations, are weak or poorly enforced.

It also happens that people, fleeing poor living or political conditions in their countries, end up in clandestine sweatshops located in hidden basements, in large cities in developed countries.

Problems in this respect include the maquilas in Latin America and the terrible issue of child labour.

All these social matters should be within our concern.

Important

In order to design and implement comprehensive and innovative preventive strategies, applicable in different settings and situations, it is important to understand:

  • all occupational risk factors and their possible impact on human health and on the environment

  • the changing nature of work and the various possible patterns

  • the social dimensions of work.

2. Pragmatic Approaches to Evaluation, Prevention and Control

As to pragmatic approaches, key words are “accepted”, “develop”, implement”.

Prevention is the ultimate goal of occupational hygiene. So much is known and, if thinking on a global basis, so little is applied. Blockages to preventive action have to be identified and overcome.

Evaluation

Quantitative exposure assessment, if well done (hence reliable), is very expensive and unfeasible in many situations (for technical and financial reasons).

We have to accept that quantitative evaluations:

  • are not always indispensable

  • should not constitute a blockage to the recommendation of obviously needed control measures

  • qualitative or semi-quantitative assessment may be an acceptable solution in some cases.

Nevertheless, it is important to emphasize that very sensitive, precise and accurate evaluation techniques are also extremely important, for example, for research to back up the establishment of “exposure-effect relationships”. Very sensitive methods are needed to detect very low (but harmful) concentrations of carcinogens, allergens and endocrine disruptors.

If quantitative evaluations are done, they should be well done; however, this should be reserved for when this kind of data is really needed and should never constitute a blockage to required preventive action.

Qualitative and semi-quantitative evaluations may be the solution in many situations and may guide to obviously needed control action.

When dealing with evidently serious hazards, instead of the classical “recognition-evaluation-control”, the steps of occupational hygiene should be “recognition-control-evaluation”.

Prevention and Control

As to preventive measures, there must be more practical solutions, applicable to small and medium size enterprises (SMEs), particularly but not exclusively in developing countries. It should be remembered that, even in developed countries, a large number of SMEs do not have good working conditions. There should more emphasis on:

  • substitution, modifications, work practices

  • less “end of pipe” solutions

  • more anticipated preventive action.

There is a need to simplify, in order to solve (not all) but more problems. However, this does not mean doing less or “n’importe quoi”. No, pragmatic approaches must be backed up by good science and sound experience. To adopt pragmatic approaches, accessible to SMEs and developing countries, does not mean careless occupational hygiene practice, if well founded.

In fact, what I would call “careless occupational hygiene practice” is to take a non-representative sample and infer an exposure situation from it. Or, to spend resources to characterize an obviously bad exposure situation, recommend the installation of a ventilation system and not controlling its quality and efficiency on delivery and thereafter through routine checks, hence not ensuring good protection (in fact, this would be an expensive careless occupational hygiene practice).

One more point: Technical/engineering measures, which remove or control hazards in the work environment are best and are to be preferred to personal measures (particularly some types of personal protection such as the respirators). Nevertheless, it should be remembered that the work environment also includes people, whose attitudes and behaviour are of paramount importance.

Examples of pragmatic approaches

Control Banding

The Control Banding approach was designed to meet the need for immediate preventive action without waiting for expensive and time-consuming, often inaccessible, quantitative exposure assessments (which often results in nothing being done). This particular method was started by the Health and Safety Executive, UK, with “COSHH Essentials”; then, IOHA prepared an international version of this approach for the ILO, which is now being tested and implemented in selected developing countries, as a joint effort by ILO/WHO/IOHA. This international version - referred to as the “International Chemical Control Toolkit”, should be promoted internationally.


At present, it covers chemicals and dusts that are used, not produced by the process or accidentally (e.g., it does not apply to gases, which are accidentally formed due to chemical reactions, decomposition of materials, burning of fuels, or occur as impurities). In any workplace, there usually are many other hazards to be controlled and ideally Control Banding should be part of a more comprehensive Prevention and Control Programme. Nevertheless, the fact remains that an immense amount of chemicals, either solid or liquid, are widely used, frequently with no controls whatsoever, everywhere, particularly but not exclusively in developing countries, and their control is already a large step towards the protection of workers’ health.

It is always recommended (in fact, it is in COSHH Essentials) to start by trying to avoid the problem (e.g., by substitution of materials, modifications, changes in work practices), asking questions such as: Do we really need this operation? this product? Can work be performed in another manner? Then, if it is not possible to prevent the use, it is recommended to control it.

The Control Banding approach leads the user through the decision-making process of preventing/controlling exposure. Moreover, the guiding principle for the Control Banding approach may and should be considered to cover other types of hazards.

The individual steps in the Control Banding approach already constitute useful training exercises for people in SMEs.


A. The first step is to establish “how toxic” the chemical in question is. This is in itself a powerful educational and awareness-raising tool because the owner (or responsible for) the SME must find the information, mostly by requesting it from the manufacturers or sellers of the product, usually a MSDS. Many people think that “chemicals are not dangerous” and have no idea of the great harm that may come from uncontrolled exposure to them.


B. Then the quantities used need to be to determined, which is another awareness step. This can even serve as an indicator; for example, a sudden increase in use may indicate that containers are being left open, or that there are fugitive emissions from closed vessels, and so on.


C. The next step is to find out/determine the volatility or dustiness of the material in question, as these have to be known. Here, the method also leads to possible source controls by asking questions such as: is it possible to replace fine powders with pellets or less dusty granules? Or, to use liquids at a lower temperature?


D. With basis on information obtained in Steps A., B., C., the situation is attributed a certain category (1, 2, 3 or 4) and types of controls are suggested for each case.

The method provides detailed control advice for a number of specific operations. Learning how to apply the Control Banding Approach is already an experience, which contributes tremendously to the development of preventive knowledge.

Of course, certain situations will call for more in-depth studies and expert advice. However, even in situations when these more detailed steps are unfeasible, a lot will already been achieved by controlling obvious hazards.

Detailed information and documents concerning Control Banding are available online, for example at: http://www.ioha.net/content/view/14/

SOBANE

The SOBANE strategy - a method developed in Belgium, so far for Noise, Heat Stress and some Ergonomic Factors, comprises 4 levels:

  • Screening obvious risk factors

  • Observation

  • Analysis

  • Expertise


It guides decision-making as to hazard control and, in many obvious cases, avoids unnecessary measurements. In more complicated situations, it indicates the need for expert advice.

Detailed information on SOBANE is available online at:

http://www.md.ucl.ac.be/hytr/new/en/


3. Strengthen the Multidisciplinary Approach and Intersectoral Collaboration

In view of the diversity and complexity of occupational health issues, from hazards to solutions, it is clear that one profession cannot possibly deal with it all and that a multidisciplinary approach is indispensable.

We have to accept the limitation of our knowledge and learn how to work with other professionals with complementary competences, not in competition, but with a spirit of collaboration, united towards one common ideal – to protect workers’ health and also the environment.

Occupational hygiene is increasingly interlinked with other professions. We must interact not only within the occupational health multidisciplinary team - including occupational physicians and nurses, ergonomists, work psychologists, but also with others, including safety engineers, environmentalists, production engineers, managers, and architects, among others. Let’s not forget the essential aspect of worker’s participation in all occupational hygiene steps.

Health, Work, Environment and Development are closely interlinked, therefore, intersectoral collaboration is indispensable, among sectors dealing with (for example) labour, employment, health, industry, agriculture, energy, education.

While still needing to establish classical occupational hygiene practice, and refine known methodologies, we have to face new challenges and develop new approaches. For this, it is necessary to accept change and adapt to new situations.

I read somewhere that “the measure of a mind’s evolution lies in its ability to accept change”. And, I believe that we, occupational hygienists, have this ability, particularly because our driving force is a noble one: to fight for decent, safe and healthy work for all.