Tag: Law

Occupational Health and the Law: UK vs. US; I ask a question


A UK case report on Occupational Health and Safety, published in August, came to my attention today. Two NHS Occupational Health investigators from UK, Charles Poole of the Northern General Hospital, Sheffield, and M Wong of the Dudley & Walsall NHS Trust Health Center, presented two clinical cases associated with a relatively new occupational industry in that nation: “The separation of garden waste from domestic waste, its collection and processing in industrial composting sites, so as to reduce biodegradable waste going to landfill“.

It is well known that any kind of disturbance created in a given environment, for any reason, can often potentially release harmful substances in air in form of aerosols, or minute particles capable of floating in air. We have seen that with the yeast-like fungal pathogen, Cryptococcus gattii, which was found, via environmental studies, to be present in high concentrations in the soil of Vancouver Island (British Columbia, Canada), and to spread during dry summer weather likely as airborne particles (a.k.a. “propagules”). Release and dispersal of spores of various molds during large-scale air-disturbing activities such as construction, renovation and/or demolition of buildings is a well-studied phenomenon in the fields of Infection Control and Epidemiology; for example, see Krasinski et al., 1985; Streifel et al., 1983. The waste separation, collection and processing appear to be no different. The investigators write:

The process of composting organic matter encourages the production of bacteria, fungi, spores and endotoxins, which may be released to air in bioaerosols. Levels of bacteria and fungi up to 106 colony forming units/m3 in ambient air have been reported in relation to composting…

The problem has not been studied well at all in the population of waste-composting workers, because – as the investigators indicate – reports of illness in these workers are relatively rare. As a result, no safe levels of exposure to such potentially hazardous aerosols have been defined in this context, nor have been the exact conditions conducive to exposure; we don’t know if, and/or how much of, the exposure depends on variables such as composition of the compost, weather conditions, steps and systemic controls engaged during the separation and collection process.

In the existing clinical literature, one of the major culprits implicated in these environment-related diseases is the ubiquitous, spore-producing mold, Aspergillus, in form of its various species, mostly commonly Aspergillus fumigatus which is the etiological agent behind various diseases involving the upper (nose and upper part of the air-tube) and lower (lower part of the air-tube and the lungs) respiratory tract. Untreated or incompletely treated, these diseases can be severe and chronic. One particularly important manifestation is the Allergic Broncho-Pulmonary Aspergillosis (ABPA, in short), which is a complex or multi-component, immunologic, inflammatory response similar to allergies or hypersensitivities – which if not detected and treated early (with antifungals and steroid immune-suppressants) can lead to serious lung damage. ABPA is generally observed in people with certain debilitating conditions, such as cystic fibrosis, or immunosuppression, but rarely in otherwise healthy individuals. In ABPA, apart from classical respiratory symptoms, reduction in lung functions, and lung abnormalities observed under X-ray, certain allergy-related responses are noted in blood (more precisely, serum) – such as:

  • Type I hypersensitivity to bits and pieces of Aspergillus (all recognized as antigens by the immune system), leading to the excessive generation of allergy-associated antibody, called Immunoglobulin E (IgE). By its action, IgE causes release of highly inflammatory mediators, such as histamine, leukotriene, and prostaglandin, from immune cells, which have both immediate and long term deleterious effects.
  • Type III hypersensitivity to Aspergillus antigens, in which small complexes of these antigens with antibody run amok through the body, depositing in blood vessels, kidneys and joints – eventually leading to immune-mediated destruction of tissues at those sites.
  • Eosinophilia, in which eosinophils, a type of white blood cells, markedly increase in number in blood and/or tissues, a common occurrence in allergy and asthma, and in parasitic (worm) infections. Activated eosinophils, a member of immune defence, are capable of causing tissue damage by various mechanisms.

The UK case report describes two late-thirties, early-forties patients, both garden waste collectors by profession, and both diagnosed with ABPA at occupational health clinics; both responded to treatment and were released with the advice not to work with waste and compost. Another member of their team, who though not ill had symptoms of asthma and tested positive for high serum IgE to Aspergillus antigens (indicating exposure) was given the same advice.

The investigators go on to make some recommendations at the end of the report. They write:

Until the results of large epidemiological studies of garden waste collectors and industrial compost workers are known, the few case reports of ABPA […] would indicate that workers with asthma who are sensitized to A. fumigatus or who have cystic fibrosis, bronchiectasis or are immunosuppressed should not work with garden waste or compost, unless their exposure to airborne fungi can be controlled. Whether asthmatics who are SPT positive or specific IgE positive to A. fumigatus will go on to develop ABPA is unknown, but they should be made aware of the theoretical risk.

Annual health surveillance by way of a respiratory questionnaire and skin prick testing is also recommended for these workers. Other cases of ABPA or EAA in garden waste and compost workers should be sought and reported, until such time that the results of a national study of UK compost workers are known.

The recommendations gave rise to some germane questions in my mind. These are, of course, valid from a clinical standpoint, and made keeping the health and welfare of the patients in mind. But given that these are related to occupational health, how do these situations play out from the perspective of the employer? How are these situations different in the UK as opposed to in the United States? For example:

  • Can/should the employers (say, a waste management firm) mandate pre-employment testing for Aspergillus-specific IgE and skin prick hypersensitivity testing?
  • Can/should the employers refuse employment to a person who tests positive for IgE and hypersensitivity because of a theoretical risk? Relatedly, can/should such an employee be made aware of this theoretical risk?
  • Should such an employee choose to ignore this theoretical risk and accept the job (or continue on the job after a diagnosis) and become inflicted with ABPA, can/should the employee be able to claim occupational exposure and Worker’s Compensation?
  • Specifically in the US context, can a Health Insurance company demand the results of these surveillance tests for a person engaged in the waste management profession, and if positive, treat this as a pre-existing condition and refuse payment in the event the employee becomes ill and needs treatment?

I don’t have the answers to any of these questions. Perhaps someone conversant with labor and/or occupational health-related laws would care to illuminate me in the comments?

Poole CJ, & Wong M (2013). Allergic bronchopulmonary aspergillosis in garden waste (compost) collectors–occupational implications. Occupational medicine (Oxford, England) PMID: 23975883

Italian Biomedical Research in Peril

Those of you who are familiar with my views on animal experimentation (e.g. see here and here) probably know and understand that in order for biomedical science to progress for the benefit of humans and animals, it is important to engage in reasonable animal experimentation. I emphasize the word ‘reasonable’, because the welfare and humane treatment of research animals remains one amongst the most important tenets guiding animal experimentation. These tenets also behoove us biomedical researchers to actively seek non-animal, alternative study methods wherever possible, and employ rigorous analytical tools to minimize the number of animals to be used.

At the same time, however, I also emphasize that animal experimentation remains a very important and crucial experimental tool. Let’s take an example that I came across in today’s Nature Medicine alert. SARS (Severe Acquired Respiratory Syndrome), a form of viral pneumonia, affects a variety of small mammals, a fortuitous fact which the scientists have utilized for over a decade to study the ways and means to stop this deadly coronavirus pathogen. However, the etiological agent of the so-called MERS (Middle East Respiratory Syndrome), another coronavirus (CoV) that is wreaking havoc in Saudi Arabia, doesn’t seem to be able to infect the usual subjects, small lab animals (such as rodents) – reports Elizabeth Devitt (DOI: 10.1038/nm0813-952) in Nature Medicine News. This has seriously hampered the search for a treatment or preventive vaccine. Teams of scientists have, of necessity, moved to a non-human primate model, Rhesus Macaques, in which the MERS-CoV does cause a form of disease that is less severe than one seen in humans. In this model, possible vaccine candidates, as well as two antiviral drugs, are to be tested.

All this is why I found a piece of news in a recent Nature News Blog highly alarming and disappointing. Reported Alison Abbott, Italian parliament approves sweeping restrictions to use of research animals.

As Allison explained, Italy, as a member of the European Union, was required to legislate the protection of animals used in scientific research, following a 2010 EU directive that was seen as striking “a delicate balance between animal welfare and the needs of biomedical research” but was also amongst the strictest of such regulations around the world. However, the Italian Senate introduced last month a series of amendments in favour of placing extreme restrictions on animal research:

  • Forbidding the use of non-human primates, dogs and cats – except to test drugs or perform translational research,
  • Mandating anesthesia use even in mildly and transiently painful procedures, such as injections, and
  • Prohibiting animal use in some specific research areas, such as xenotransplantation (transplantation of cells and tissues between species, an important research area associated with transplant medicine), and addiction.

Not surprisingly, the scientific establishment of Italy is crying foul, voicing the concern that these measures would seriously hinder important biomedical research in Italy. It is not difficult at all to see why they should feel this way. Allison’s blog post is followed (at the last reading) by an illuminating discussion by five illustrious commenters, some noted biomedical researchers amongst them: neuroscientist Prof. Stefan Treue (Director of the German Primate Center, and Professor of Cognitive Neuroscience and Biological Psychology, University of Göttingen), Constitutional scholar Prof. Francesco Clementi (Professor of Political Science, University of Perugia), neuroscientist Prof. Nikos Logothetis (Director, “Physiology of Cognitive Processes” Department, Max Planck Institute for Biological Cybernetics, Tübingen), neuroscientist Prof. François Lachapelle (Research director, National Animal Welfare Office, INSERM) and Science blogger Dr. Paul Browne of the Speaking of Research blog. I encourage everyone to head over to Allison’s blog and read these comments.

Paul Browne’s comment brought back to my mind an excellent 2010 post he wrote along with Dr. Allyson Bennett on the Basel Declaration, “a declaration that affirms commitment to responsible research and animal welfare and calls for increased effort to facilitate public understanding of the essential role that animal studies play in contributing to scientific and medical progress” (Full Disclosure: I am an individual signatory to the Basel Declaration).

Particularly in relation to the Italian legislation’s intent to allow animal research for some, but not all, biomedical research, this line from the Declaration is especially important:

“…Biomedical research in particular cannot be separated into ‘basic’ and ‘applied’ research; it is a continuum stretching from studies of fundamental physiological processes to an understanding of the principles of disease and the development of therapies.”

Paul’s comment after Allison’s post includes a note of hope. He wrote, “… it has become apparent that the voices of science are beginning to be heard by Italian politicians.” I hope that is true – not only for Italy, but across the world, especially in the US, as well.