When employees develop skin problems at work, they usually believe that there is a simple explanation as to the cause. While this is possible, there are usually many contributing factors, some of which may originate outside the workplace. Chris Packham investigates.
When trying to get to the root of a skin problem, the following should be considered:
- there may be no single cause, but a combination of factors that jointly cause the skin problem;
- the problem may be only partly due to occupational conditions and non-occupational exposures may be the primary, or a significant contributory factor; and
- constitutional factors, eg atopy, about which the employee may have had no prior knowledge, may play a significant role.
Given that an incorrect diagnosis can have a subsequent negative effect on an employee’s recovery and ability to remain at work or lead a normal life, it is essential that any suspected occupational skin problem is correctly investigated.
It is also important to ensure that others carrying out the same, or similar, work will not develop the same skin disease in future.
First, we need to clarify what we mean when we speak about an occupational skin disease. One definition is: “A clinically recognisable impairment of the skin’s normal state due entirely or substantially to conditions in the workplace” (Packham, 1998).
Factors to be considered
For example, a construction worker develops hand dermatitis. They work on a construction site and have contact with cement. Cement contains chromates that are well documented as sensitisers. The worker has been patch tested as positive to chromium. So, it is reasonable to conclude that they may have some allergic contact dermatitis due to skin contact with the cement.
However, cement is also a potent skin irritant, so almost certainly there will be some irritant contact dermatitis forming part of the skin condition. How much of the skin problem is allergic and how much is irritant is impossible to state with any certainty, given the limited diagnostic techniques available. Furthermore, their skin will almost certainly have been exposed to irritant chemicals away from work and these may have also contributed to the skin condition.
There also needs to be a consideration of physical factors, such as skin abrasion from handling rough cement blocks, and exposure to wind, cold and low humidity in winter on the same construction site.
The worker may also be pre-disposed to developing skin problems, due to a genetic condition known as atopy, but up until now, they have been unaware.
Additionally, they may suffer from some other constitutional condition that has not previously been identified, but that has caused a significant reduction in the ability of their skin to resist damage from both occupational and non-occupational factors.
Psychosomatic factors should not be ignored. It has been well established that stress can cause, or contribute to, what appears to be contact dermatitis. The stress need not be from workplace conditions, but can be due to family problems or other causes.
Ingestion can also contribute to allergic skin reactions, particularly if that person has become sensitised to a particular substance and it is contained in their diet. For example, a change in diet that increases nickel uptake could also result in allergic contact dermatitis.
Bearing in mind that employees only spend between 40 and 48 hours at work, out of a total of 168 hours for the complete week, it will be necessary to ascertain and evaluate any potential non-occupational conditions and exposures that might either be the cause of, or a significant contributory factor to, their skin problem.
This point illustrates some of the complexities that can exist when an investigation into a suspected occupational skin problem is required. Given the limited range of diagnostic techniques available, we often find ourselves in a position where we cannot always be certain about the true cause(s) of skin problems.
In such cases, all we can do is ensure that any potential contributory factors are identified and any suitable measures are taken to neutralise them. We can then attempt to “manage” the condition through appropriate measures such as changes in operating procedures, provision of suitable personal protective equipment and high standards of skin care.
To illustrate why care is needed when investigating a suspected case of occupational contact dermatitis, we will focus on two cases later in this article.
A structured approach
Given the complex way in which our skin can interact with our environment and the many factors that can affect it, investigating a suspected case of occupational skin disease should be approached with caution. A careful, structured approach is required.
It is beyond the scope of this article to provide a detailed description of each element in this required sequence of actions, but the following synopses outline the main purpose of each stage and what it should include.
Meet with person(s) and take their history
This is the first step in establishing the background to the particular skin problem. A standard questionnaire should be used to ensure that all relevant factors are taken into consideration. This should also include a visual assessment and the worker’s description of the history of the current problem, any previous skin problems (even if not occupation induced) and any non-occupational activities undertaken. The workplace environment and tasks should be studied to identify any relevant exposure.
Study workplace environment and tasks; identify any relevant exposure
As an occupational skin problem is generally caused by the reaction of the skin to conditions in the working environment, it is essential to identify what is happening when the worker carries out normal tasks.
We need to determine exactly what the employee is doing, and what skin exposures are occurring to what chemicals. The comments made on this in the risk assessment for his or her task(s) are very relevant. A check should be made to ensure that not only is the risk assessment still relevant, but also that what was implemented as skin exposure control is still appropriate and was in effect during the period leading up to the skin damage.
Additionally, we should examine the skin of any others who are carrying out similar activities, or working in the same area, to determine whether or not their skin is affected. In many cases, one employee may have complained, whereas others with similarly skin problems have considered this unimportant.
There is often the attitude that the skin condition “goes with the job”, and thus some workers will not have reported it. If a number of employees are carrying out the same task, with similar exposures, and also have damaged skin, then this can be an indication of an occupational cause.
Some of the investigation process can be based on the risk assessments presumably already completed for skin exposure, but what we are trying to obtain is a clear picture of any hazards and exposures that could be contributing to the skin problem.
Connection between exposure and skin condition
Occasionally, there will be a clear and undisputable connection between exposure to a chemical and the skin condition. Such a situation would be, for example, where the damage to health could only be attributed to a known exposure to an acid found only within the workplace, seeing as this would be acute and it is possible to exclude a non-occupational exposure.
A similar situation would be where an employee is known to be allergic to a particular chemical, and has reacted as a result of a proven workplace exposure at a level sufficient to elicit an allergic reaction. However, in the majority of situations, caution should be
exercised in deciding whether or not there is one simple cause.
As has been previously shown, there is frequently a combination of factors that lead to the skin disease. This is one aspect of the investigation where extreme caution is required, and where a clinical investigation will be needed in the majority of cases.
Refer to dermatologist
This is where ideally we need the assistance of a dermatologist with specialised training and experience in occupational skin diseases, or at least one that has suitable expertise in investigating contact dermatitis and contact urticaria.
The dermatologist will need an appropriate briefing so that they have an objective assessment of what is happening in the working environment. Without this, they may not be able to identify all the potential causes. This can result in a diagnosis that may be clinically accurate, but occupationally irrelevant. In an investigation that I conducted, a diagnosis had been made of occupational allergic contact dermatitis to formaldehyde. As formaldehyde was present in the workplace, the employer had assumed that this was the cause of the employee’s facial dermatitis.
However, investigation revealed that the worker could not have been exposed to this chemical and that the facial dermatitis was, in fact, due to a change in diet.
Similarly, case study 1 (see below) describes another investigation where the diagnosis, albeit correct, was not relevant.
Assess relevance of report from clinical investigation
Once the diagnosis has been received, this should be compared with the knowledge that has been gathered to establish its relevance.
If it is decided that it is relevant, then an action plan can be formulated to help manage the skin condition, so that the worker can ultimately resume a normal role and working activities.
Action to manage condition
If it is decided that the damage is occupational, then risk assessment and exposure management strategies should be reviewed and appropriate modifications introduced. Useful guidance can be found in a document produced by the Royal College of Physicians: “Dermatitis – occupational aspects of management”.
Hopefully, the action taken to manage the condition should result in the worker’s skin returning to normal and their being able to return to their employment with no further problems.
Should this not happen, then further investigation will be necessary to identify what has been missed in the original investigation. This may require the involvement of people with specialist expertise, eg an occupational hygienist, toxicologist, or even a chemist, as changes in the hazard presented by the chemical may not have been correctly identified in the first place.
1. Allergic contact dermatitis due to nickel-plated components
In a plant producing small, complex metal assemblies, several of the components were nickel plated. Nickel is our most common sensitiser, causing many cases of allergic contact dermatitis.
A female worker, after two years working in assembly, developed pronounced hand dermatitis. This cleared up in the two weeks that she was on holiday, but reappeared within a week of her returning to work. She was referred to the local dermatology clinic, which carried out a patch test. This showed that she was positive to nickel. The logical assumption was that the employee had a simple case of occupational allergic contact dermatitis due to workplace exposure to the nickel in the plated components. Remedial matters such as relocation and compensation were under consideration.
Advice was required on the measures needed to ensure that other workers performing the same work did not develop a similar skin problem. The investigation included a simple test to establish whether or not there was a genuine exposure to nickel.
Most people who are allergic to nickel can handle stainless steel (chrome-nickel-steel alloy) with no skin reaction, seeing as the nickel is so tightly bound into the alloy that no nickel molecules are being released to cause the skin reaction. The test involved the use of a chemical that changes colour in the presence of free nickel.
A test on all the components that this employee would have handled at work revealed that none were releasing nickel, thus excluding the occupational allergic contact dermatitis due to nickel exposure.
Meanwhile, further investigation revealed that the woman was employed in her spare time as a hair stylist, and the problem was an irritant contact dermatitis (which does not show in a patch test) due to contact with water and shampoos. The condition cleared during her holiday as she was also not carrying out the part-time occupation.
2. Latex allergy with accompanying anaphylaxis
A care home worker (female, 58, atopic) who had experienced several previous outbreaks of dermatitis was undergoing first-aid training. When kneeling on a carpet she suffered an anaphylactic attack, and had great difficulty breathing. She was rushed to hospital, where she was given an injection of adrenaline, to which she did not respond. She did eventually recover.
A radioallergosorbent test was carried out, which revealed that she was positive to several substances, including latex protein. The assumption was made that her reaction was due to the inhalation of dust from the rubber carpet backing and we were asked if we could help with the management of her condition.
An investigation revealed that the carpet backing was synthetic rubber, ie it contained no natural rubber latex proteins, and thus could not have been the cause of her reaction. In fact, she was sensitised to latex protein, but not allergic (ie, although her immune system was primed to respond with an allergic reaction, she did not actually develop it).
She was convinced that her problem was an allergic reaction to rubber and even stated that she reacted to the soles of her daughter’s boyfriend when he was standing on the doorstep. In reality, she could handle natural rubber latex without a problem, provided that she was not aware that what she was handling was rubber. She would react to plastic, containing no rubber protein, if she thought that this was rubber.
This psychosomatic reaction (undifferentiated, idiopathic, somatoform anaphylaxis) is more common than many realise. In one German university, a department deals exclusively with this issue.
Investigating a case where a worker has developed what is, at first glance, an occupational skin disease, can be simple.
However, unless we at least consider the many other factors that could affect that person’s skin, it is all too easy to reach a conclusion that may lead to inappropriate treatment and actually make the problem worse.
We need to recognise that a thorough investigation may take time and require patience and commitment by those involved in order to reach a satisfactory conclusion.
Ultimately, it may not be possible to identify the true cause with any certainty. It may be that the best that can be done is to manage the condition so that the affected person can remain at work. Of course, in some cases even this may not be possible and we may be limited to redeploying or retraining the employee in an alternative occupation.
Given this, it should be apparent that the emphasis should be on pro-active skin management, so that we minimise the probability of having to deal with what might appear to be an occupational skin problem.
Packham CL (1998). “Essentials of occupational skin management”.
Neither the author nor EnviroDerm Services can accept any liability for issues arising out of action taken as a result of this document.