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Sawmills in the Canadian province of Alberta were surveyed in order to identify occupations at greatest risk and to guide compliance measures. Two hundred and ten wood dust samples (inhalable) were collected from nine Alberta sawmills using Institute of Occupational Medicine (IOM) personal samplers. Nine percent of samples exceeded 5 mg/m3 8-hour time-weighted average (TWA) for total dust. There was a significant statistical difference (p < .001) between the median and geometric mean inhalable particulate matter (IPM) dust levels for 4 aggregated occupational groups. Levels were highest for cleanup workers (3.5 mg/m3), followed by the maintenance, planermill, and sawmill occupational groups, as were other measures of dust levels. In response to these findings, the Alberta Forest Products Association undertook a program to train sawmill managers to implement these recommendations on engineering controls, administrative controls, and personal protective equipment.

The Fort McMurray Demonstration Project in Social Marketing attempted to achieve mutually reinforcing effects from thematically coordinated educational and awareness efforts in the community as a whole and in the workplace and the inclusion of occupational safety within the framework of a community health promotion project. The study community was Fort McMurray, a small, industrial city in northern Alberta. The Mistahiai Health Region, several hundred kilometers to the west and also dominated by one city, Grande Prairie, served as the reference community. The intervention was based on media and events staged at public events, with supporting educational activities in schools and the community. It relied heavily on community-based partners and volunteers. Data on healthcare utilization of selected preventable injuries were obtained from Alberta Health for the time period 1990-1996 for the Regional Health Authorities of Northern Lights, where the only large population centre is Fort McMurray, and Mistahia. Age-adjusted aggregate injury rates were analyzed for evidence of an effect of the intervention. Severity was measured by proxy, using the number of diagnostic claims submitted for reimbursement for medical services in a given year. The communities differed in age-specific injury rates, with Fort McMurray showing higher rates for residents aged less than 55. Young adults and older adolescents showed higher levels of severity. Injury rates fell substantially and at similar rates in both communities over the five-year period. However, in both communities injury rates were already falling before the intervention in Fort McMurray began and continued to fall at about the same rate, slowing toward the end of the period. No evidence was found for an effect of the Project or for acceleration of the reduction in injury frequency in the intervention area. Over the period, fewer medical services were delivered in office settings and more in emergency rooms, in both communities. The Fort McMurray Demonstration Project in Social Marketing achieved an intensity of intervention and community participation that is unlikely to be sustainable in other communities. Despite this level of effort, the study did not achieve an unequivocal, demonstrable reduction in injury frequency above what was already occurring. This may have been due to a more powerful trend manifested as injury reduction across the province.

(2009). Chairing a Session at a Scientific Meeting. Archives of Environmental & Occupational Health: Vol. 64, No. 2, pp. 141-144.

Publisher Summary The lung is both a major pathway for toxic exposures and a vulnerable target organ in its own right. Receiving many liters of airflow per day, it has evolved a variety of host defenses and barriers to protect its structures, especially the delicate alveolar membrane. For that reason, pulmonary toxicology cannot be understood without a firm grasp of host defense mechanisms. Concepts of the respiratory tract as a target organ have changed fundamentally in the last 10 years with the discovery of ultrafine particles and their seeming ability to avoid these defense mechanisms, penetrate the vascular barrier and exert effects outside the lung. As well, the lung is a relatively limited (although not simple) structure which can respond only in a few different ways to a toxic event. The inflammatory effects of ultrafines and of synthetic nano-sized particles were initially unexpected and their study has opened new doors to the investigation of the lung and its responses. Inhalation toxicology is one of the most technically difficult fields of experimental toxicology and the study of particles presents particular challenges.

Publisher Summary Dusts are finely divided particles in the solid phase which, when suspended in air, form aerosols. Aerosols may also form from particles in the liquid phase, or mists. Aerosols have a variety of properties and characteristic behavior depending on composition and air movement. Dusts within aerosols behave in air and adjacent surfaces according to their mass, density, size, dimensions, and electrostatic charge. Once inhaled, their fate in the upper respiratory tract and in the lung is determined by their mass, size, shape, and electrostatic charge. Once deposited in the lung, they may persist or be degraded according to their composition and water solubility. Only then does the dust exert any physiological effect it will have and aerosol science and particle deposition studies give way to toxicology. Some dust diseases of the lung may be associated with asthma and immunological responses, such as hypersensitivity pneumonitis, hard metal disease, and beryllium disease, but the majority are characterized by a fibrotic response to the deposition of dust in the alveolus, resulting in a pneumoconiosis. Three are particularly troublesome because of the intensity of the fibrosis and how common they are in the workplace: silicosis, asbestosis, and coal workers' pneumoconiosis.

Canada is now considering recommendations of the Federal-Provincial Working Group on Air Quality Objectives and Guidelines to adopt objectives for fine particulates that will be among the most stringent anywhere in the world and that may be technically unobtainable in the short term. No Canadian city would be in compliance at this time if these objectives were adopted. The fine particulate issue is also driving a fundamental change in the way that Canada harmonizes regulations on air pollution. In the United States, standards are set by the federal government for implementation by the states; the federal government has primacy. These standards are mandatory as a minimum level of control, although states may impose more stringent standards. By contrast, in the Canadian system the federal government does not have primacy and environmental protection at the local level is mandated to provincial governments. Canada has chosen to set guidelines negotiated between the federal government and representatives of provincial governments, in the expectation that these guidelines will influence the individual provinces to adopt similar standards. The role of guidelines, as opposed to standards, is to drive voluntary change and to influence public opinion. In the past, these guidelines were set to be more stringent than U.S. National Ambient Air Quality Standards and reflected the reality that urban air pollution levels in most large Canadian cities were generally lower than their U.S. counterparts. In 1997, a new process was initiated to bring the development of recommended air quality criteria into a more scientific formulation. National Ambient Air Quality Objectives will now be developed in a more transparent, accountable and science-based process. They will also be recommended rather than mandated but as objectives will carry the expectation that all jurisdictions in Canada will eventually harmonize their own standards to these norms. The first two objectives under this new process are fine particulates and ozone. For the purpose of this discussion, we shall confine our remarks to fine particulates. A large body of evidence was compiled into a report 1 that constituted the briefing document for a Stakeholder Consultation Workshop convened by the Atmospheric Environment Service of Environment Canada in December 1997. Included in this dossier was the report of the Federal Provincial Working Group recommending new air quality objectives for fine particulates. 2 The implication of these recommendations was staggering. Based on their reading of the available evidence, and driven primarily by estimates of lives saved through reductions in mortality associated with fine particulate levels in urban areas, the Federal Provincial Working Group recommended an objective for PM 10 of a 24hour average concentration of 40 µg/m 3 and for PM 2.5 of 20 µg/m 3 . This compares with the U.S. Environmental Protection Agency’s (EPA’s) previously proposed (now remanded) National Ambient Air Quality Standard of U.S. 24-hour averages of 150 and 65 µg/m 3 , respectively. Canada would have no equivalent to the previously proposed U.S. annual averages of 50 and 15 µg/m 3 , respectively, relying on the 24

The clinical interpretation of trace element analysis has lagged behind the technology available to measure the elements in body fluids. Reports can be difficult to interpret and requires knowledge of toxicokinetics, the dynamics of how the trace metals accumulate and pass through the body. Trace element analysis is best used for specific applications, such as establishing levels of exposure, biological exposure indices, biomonitoring of populations, and to confirm an association following a compatible diagnosis. It is not well suited for screening individual patients. Chelation treatment may follow inappropriate trace element determinations and may carry a risk of side effects, some life-threatening. Trace element analysis should be used sparingly and with full understanding of what the results are likely to mean. The physician should only order the test with a clear idea of why he or she is doing so and what he or she will do with the result.

The literature on the phenomenon of community resistance to local siting of undesirable facilities, the so-called `not in my backyard' syndrome (NIMBY), emphasizes community civic characteristics and motivation. We describe a case study in which prior political history played an important but not obvious role. The Aurum project was a proposed landfill for the city of Edmonton, Alberta (Canada) proposed in 1989 and 1990 for an isolated and mostly vacant site within city limits but across a river from the developed area. The siting was bitterly but successfully opposed by the government and residents of the adjacent area. Investigation determined residual, unspoken resentment among county residents against an attempt by the city to annex it decades before. It was concluded that in this instance, and probably many others, the political history of the community plays a major role in conditioning their response to `locally undesirable land use' (LULUs) and the NIMBY phenomenon.

Sodium hydrosulfide and dimethylsulfide duplicate the effects of hydrogen sulfide in causing coma in Sprague-Dawley rats and are additive for lethality. Nitrite, pyruvate and dithiothreitol had no significant effect on coma or lethality but bicarbonate with and without glucose reduced duration of coma. This finding suggests an antidotal treatment.

(2007). Traditional Knowledge: Challenge or Complement to Science? Archives of Environmental & Occupational Health: Vol. 62, No. 4, pp. 167-168.

Concerns regarding adverse health effects of exposure to environmental pollutants among children are increasing. This subject area is particularly important in China because of environmental pollution problems associated with rapid development and a large population. The authors provide what is, to their knowledge, the first review in China of English- and Chinese-language literature regarding the current status of environmental exposures to children in China and the impact of these exposures on the health of children. Children in China are exposed to diverse environmental pollutants, including traditional pollutants such as lead and mercury and emerging pollutants such as phthalates and perfluorinated compounds. Incidence and prevalence of certain childhood diseases have increased in last decades. In China, a limited number of data on environmental exposure and children's health are available, and further high-quality studies are needed.

Here we present an overview of the experimental evidence and of the conceptual basis for the involvement of lamins and nuclear envelope proteins in a group of genetic diseases collectively referred to as laminopathies. Some of these diseases affect a specific tissue (skeletal and/or cardiac muscles, subcutaneous fat, peripheral nerves), while others affect a variety of tissues; this suggests that the pathogenic mechanism of laminopathies could reside in the alteration of basic mechanisms affecting gene expression. On the other hand, a common feature of cells from laminopathic patients is represented by nuclear shape alterations and heterochromatin rearrangements. The definition of the role of lamins in the fine regulation of heterochromatin organization may help understanding not only the pathogenic mechanism of laminopathies but also the molecular basis of cell differentiation and ageng.

Objective We assessed the demographic profile and opinions of current occupational medicine (OM) physicians on the importance of specific core competencies. Methods A random sample of 1500 OM physicians listed in the membership directory of the American College of Occupational and Environmental Medicine (ACOEM) were asked to complete a voluntary survey. Results Six hundred and ten OM physicians completed the survey. Fifty two percent worked in clinical settings, and 16% worked in corporate or industrial settings. Eighty percent were satisfied with their choice of careers. Conclusions OM physicians appeared to be highly trained, with 60% certified in OM and 68% board certified in other specialties. The OM physicians valued staying current in the field, understanding the relationship between occupational exposure and health, and communicating with stakeholders most highly. Occupational physicians are an important source of knowledge regarding what competencies and core knowledge areas are important for OM practice.

The so-called New Economy of the 1990s failed to deliver its promise of clean work and huge leaps in productivity; what really happened was an intensification of economic pressures on marginal workers. The effects on employment include: increasing income disparities, fewer jobs that lead to viable career tracks, less secure employment, longer working hours, and higher risk of uncompensated unemployment. Workers who are either newly entering the workforce or who do not have the training or skills to trade up in employment are under pressure from falling middle- and lower-income wage scales and increasing income disparities. Their opportunities are increasingly limited, whether by seeking better-paying jobs with other employers or moving up the now-shortened ladder at one employer. They face a declining choice of employment opportunities and well-paying jobs that tend to be concentrated in residual dangerous work in manufacturing or service subsectors that are often small or economically marginal. These forces appear to be pushing workers into accepting jobs in the diminishing but still substantial number of jobs that remain that are dirty and dangerous, as illustrated by the extreme example of McWane Pipe. Those who are forced into these dangerous jobs will once again most likely be the poorly prepared, the new-entry, the recent immigrant, and the illiterate worker. National occupational injury statistics may conceal the experience of these marginal industries by aggregating them into much bigger economic sectors. To understand this phenomenon, we need studies that examine the social choices and tradeoffs involving employment from the point of view of the worker and develop a means of monitoring these tradeoffs.

Both ethics and law are based on value systems. George Lakoff has contributed to our understanding of the value systems that influence attitudes toward public issues in his book, Moral Politics: What Conservatives Know That Liberals Don't (University of Chicago Press, 1996). He argues that two antagonistic but co-existing moral systems influence attitudes toward public issues. Both are derived from metaphors of family life and child development and the “morality” of allowing certain actions. One moral system stresses individual responsibility and risk-taking, the other empathy and mutual assistance. The tension between these value systems explains much in political debate; issues generally tend to fall on one side or the other. Occupational health and related issues, almost uniquely, have the unfortunate characteristic of falling short in both. Our best efforts may be judged “immoral” by the strictest interpretations of both systems, even when they are successful. The practical implication is that we must not accept this pattern of thinking. The work relationship is not like a family. It is important to separate issues in occupational health from this pattern of thinking in both professional and public discourse.

Health and medical knowledge are essential to the resolution of disputes in law and administrative applications (such as workers' compensation) and provide essential input into public policy decisions. There are no socially agreed-upon rules for the application of this knowledge except in the law. On a practical level, the legal system lacks the capacity to evaluate the validity of knowledge as evidence and therefore relies heavily on expert opinion. Over the last 30 years, an approach called "critical appraisal" and "evidence-based medicine" addressed a similar problem in medical practice and established norms for the acceptance of evidence in clinical medicine. A similar evidence-based framework may be possible for applying knowledge of health and medicine to dispute resolution in the law. One critical issue is how to apply scientific evidence when the standard is "more likely than not" rather than scientific certainty. Another is how the generalizations drawn from epidemiology and population-based sciences are interpreted and individualized, as they must be, for the case at hand. A related issue is how risk is interpreted for an individual after the fact, when conventional probability treats risk before the fact and conventional biostatistics applies primarily to a population. This emerging approach is called "evidence-based medical dispute resolution".

Objectives: Ethical codes, or systems, are conditioned and their enforcement is permitted by social processes and attitudes. In occupational health, our efforts to adhere to our own ethical frameworks often are undermined by forces and interests outside the field. Failure to acknowledge the profoundly social nature of ethical codes impedes our ability to anticipate consequences, to legitimate decisions based on utility and benefit, and to find social structures that support, rather than invalidate, our view of ethical behavior. We examine three sets of social philosophies. Methods: Jane Jacobs, the visionary urban planner, has written Systems of Survival: A Dialogue on the Moral Foundations of Commerce and Politics, which is a restatement in modem, terms of a critical passage in Plato's most important dialogue the Republic. She (and Plato) postulate two major ethical systems, renamed here the guardian system, which is characterized by loyalty, cohesiveness, and confidentiality, and the marketplace system, which is characterized by trade, decentralization, and shared information. Occupational health, in this formulation, often runs afoul of the guardian mentality and also may be subject to inappropriate negotiation and compromise in the marketplace system. George Lakoff, a semiotician, has written Moral Politics: What Conservatives Know That Liberals Don't, which argues that there are two fundamental social paradigms based on concepts of the family. One, which he calls the Strict Father, emphasizes discipline, the positive aspects of taking risks, and the freed to individuals to be self-sufficient. The other, which he calls the Nurturing Parent, emphasizes empowerment, the positive aspects of security, and the need for community and relationships. Occupational health practice violates aspects of both and therefore is supported by neither. Classical Chinese, thought involved, many schools of thought, including Confucianism and Legalism. It has been suggested that Confucianism provides little support for government regulation or occupational health, however this is questioned. Conclusions: Occupational health may improve its standing as a social priority by recognizing and maneuvering within social frameworks that accomodate it, rejecting social frameworks that invalidate it, and reinforcing positive cultural trends within society that support it.

Homeland security requires protection of the essential infrastructure that provides and delivers goods and services that supply on-going needs and that maintain the economy. Protecting the workforce, senior managers, and essential personnel is essential, not only to preserve critical industries but to maintain business continuity to prevent severe and prolonged economic disruption. Most large employers have an under-utilized resource available for this purpose. This is the occupational health service, which already serves many compatible functions and houses personnel with many of the requisite skills. Occupational medicine specialists, occupational health nurses, and industrial hygienists have special training on chemical, biological, physical and psychological hazards in the workplace that translate readily to homeland security applications. Developing emergency management capacity within the occupational health service builds on its traditional role in disaster planning and derives a dual benefit from the investment. The leadership organizations in the three professions have taken the lead in developing the Occupational Health and Disaster Expert Network (OHDEN), an Information Sharing and Analysis Center (ISAC) -based network for this purpose.

“Exposure science” has declared independence from conventional exposure assessment, in which it was subordinated to support of epidemiological studies, and to environmental monitoring, in which ope...

The editorial that leads this issue talks about risk assessment for reproductive hazards and how they are managed. This class of hazard seems to make people nervous, partly out of fear of liability...

Elgstrand K, Petersson NF, eds. Occupational Safety and Health for Development. Stockholm: Royal Institute of Technology, 2009, 798 pp. ISBN 978-91-633-4798-6. Also available online at http://kth.d...

The Occupational Medicine Forum is prepared by the ACOEM Occupational and Environmental Medical Practice Committee and does not necessarily represent an official ACOEM position. The Forum is intended for health professionals and is not intended to provide medical or legal advice, including illness prevention, diagnosis or treatment, or regulatory compliance. Such advice should be obtained directly from a physician and/or attorney.

The threat of bioterrorism has led to a reinvestment in public health, but not necessarily in a manner that ensures efficient, reliable and cost-effective improvement in services. Public health officials fear that homeland security is distorting the priorities of public health and diverting resources from the essential work they are already doing. They fear that homeland security requirements may have erosive effects on confidentiality and in compromising their core mission of health promotion and disease prevention. Specific issues include cutbacks in promised support, diversion of funding to single-purpose projects, concerns over maintaining confidentiality of client services, abuse of the extensive police powers given by state legislation to public health authorities, and lack of integration with existing public health systems. The reasons for these concerns are deeply rooted in the history of public health, in which the legal authority of health agencies included police powers and even detention. Public health leaders would prefer a policy of "dual use" or "dual benefit" in which capacity is added to enhance the operation of the public health system in general while adding new capability in emergency response. Such a policy would ensure benefit from the investment even if no bioterrorism event ever occurred locally and would enhance the reliability of the system. For example, a single-purpose surveillance program for bioterrorism is likely to have an unacceptably a high risk of failure and unreliability in a bioterrorism event if it is not regularly tested by the type of outbreak that occurs many times a week in every metropolitan health department. A small but articulate group of public health leaders, led by Victor W. Sidel, have even questioned the ethics of collaboration between public health and police or intelligence services. This article suggests that such cooperation is actually necessary and recommends advance guidelines and policies, legal clarification, combined multidisciplinary training, and mutual trust and understanding among public health, law enforcement, and intelligence professionals, in order to protect the integrity of essential services and the valid concerns of the public health system.

This paper describes a large-scale investigation into the effects of licensed air emissions from sour-gas processing plants on the health and productivity of beef cow–calf herds in the province of Alberta, Canada. In conjunction with a geographical information system, two atmospheric-dispersion models were used to assess historical exposures at 5726 beef cow–calf farm-sites from 1987 to 1990. We did secondary analyses of health, productivity, and management data, from a government-extension survey previously administered to beef cow–calf producers across the province. Statistical models (adjusted for potential confounding and clustering within herd and over time) were used to determine associations with estimates of sour-gas emission exposure. All analyses were conducted at the herd-level. There were no significant ( P >0.05) detrimental associations of exposure and the annual herd risk for culling, calf-crop delivered, calf-crop season profile, stillbirth and twinning, calfhood mortality, or calf-crop weaned.

We describe two approaches for exposure assessment that we used in a large-scale retrospective cattle study conducted in Alberta, Canada. Sulfur dioxide (SO 2 ) was the surrogate measure of exposure to a complex mixture of combusted sour-gas emissions. Monthly air pollution dispersion modeling (1985–1994) (based on individual industrial source processing-plant engineering specifications, emission volumes, and meteorologic information) provided exposure isopleths of sulfur dioxide concentration from each of 231 sour-gas processing-plants across the province. In contrast, a simpler measure of proximity to source(s) of varying emission rates was applied in a geographical information system based on simplified pollution decay at increasing distances from each point source. Province-wide (663,000 km 2 ) surface analysis (by exposure-level classification) produced a contingency coefficient of 0.68 between the two exposure estimates. Annual exposure estimates at the 1382 dairy and 5726 beef cow-calf farms studied were highly correlated over the 10-years period ( r spearman =0.82 and 0.83, respectively), while monthly exposure estimates were somewhat less correlated ( r spearman =0.80 and 0.82, respectively) for the two exposure assessment methods. Crude exposure estimates from each method were similar in both direction and magnitude.