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T L Guidotti

Publications and source records attributed to T L Guidotti.

At least 37 records · Page 2Linked to original sources
PubMed1996

Considerations for regional health authorities in the provision of environmental health services.

As population health programs, environmental health services differ fundamentally from other forms of health service delivery. At a time when the health sector is striving for integration, the incorporation of these unique services into the delivery system presents a unique challenge to policy makers and administrators across the country. The University of Alberta recently completed a comprehensive review and redesign of locally governed and delivered environmental health protection services in Alberta. This paper outlines the key issues and unique features surrounding the delivery of environmental health services and presents the study team's suggested approach to addressing these issues.

Alberta↗
PubMed1996

The Fort McMurray Demonstration Project in social marketing: health- and safety-related behaviour among oil sands workers.

This is the first round in a series of surveys conducted in Fort McMurray as part of the Fort McMurray Demonstration Project in social marketing. This component of the survey was intended to focus on the most prominent group of employed workers in the community and to compare their patterns of response with the community as a whole. Respondents to the survey were overwhelmingly male (96%), married (72.9%) and living in households of two to five persons (87.9%). They were predominantly aged 30-44 (55%) and graduates of high school (53.5%). Younger male workers (below age 30) were more likely to have a high school diploma (78.3%) or some additional technical or vocational training (21.7% compared to 12.5% overall) and to be unmarried or separated. Attitudes toward safety-related behaviours were stronger than for respondents from the community as a whole. Approximately 70-100% of all age groups and both sexes showed strong agreement with attitudes involving child car seats and the unacceptability of drinking and driving. These attitudes include strong advocacy of vigorous enforcement of occupational health and safety standards. However, they showed a variability similar to the community as a whole in behaviour at home compared to work, generally reporting more consistent use of personal protection on the job than in their own homes, particularly hearing protection. Even so, they were much less likely to perform stretching and warm-up exercises prior to exertion than community residents in general. The potential may exist to transfer the technology and attitudes from workplace health and safety to community safety. One possible strategy to accomplish this is to involve workers in this industry directly in community initiatives. This strategy may be generalizable to any community in which there are major employers who place a heavy emphasis on risk control and occupational health and safety.

Adult↗
PubMed1996

Hydrogen sulphide.

Hydrogen sulphide (H2S) is the primary chemical hazard in natural gas production in 'sour' gas fields. It is also a hazard in sewage treatment and manure-containment operations, construction in wetlands, pelt processing, certain types of pulp and paper production, and any situation in which organic material decays or inorganic sulphides exist under reducing conditions. H2S dissociates into free sulphide in the circulation. Sulphide binds to many macromolecules, among them cytochrome oxidase. Although this is undoubtedly an important mechanism of toxicity due to H2S, there may be others H2S provides little opportunity for escape at high concentrations because of the olfactory paralysis it causes, the steep exposure-response relationships, and the characteristically sudden loss of consciousness it can cause which is colloquially termed 'knockdown.' Other effects may include mucosal irritation, which is associated at lower concentrations with a keratoconjunctivitis called 'gas eye' and at higher concentrations with risk of pulmonary oedema. Chronic central nervous system sequelae may possibly follow repeated knockdowns: this is controversial and the primary effects of H2S may be confounded by anoxia or head trauma. Treatment is currently empirical, with a combination of nitrite and hyperbaric oxygen preferred. The treatment regimen is not ideal and carries some risk.

Animals↗
PubMed1995

Managing environmental research in a government agency: priorities in chemical hazards.

In 1993, I served as consultant to a Canadian government agency with responsibility for the characterization of chemical hazards. The work was divided into three tasks: (1) an extensive review of present priorities within the agency, (2) a survey of recognized experts to determine perceived "gaps" in the coverage of research on chemical hazards, and (3) preparation of a set of recommendations. The 23 perceived gaps identified by the expert panel cluster into three general groups: existing projects designed to protect the health of Canadians, practical solutions to concrete problems, and robust methods for dealing with chemical mixtures and generalizable research methodology. A specific set of priorities was recommended to the agency and several procedural changes were proposed: encouragement of working partnerships, a mechanism for ongoing review of priorities, and consideration of alternatives to dedicated research projects, such as emphasizing behavioral rather than toxicological studies on tobacco smoke. A research management system was also proposed based on a matrix organization in which accountability is not divided but which features research-driven cross-program interdisciplinary colloquia within the agency. The general approach and specific findings in this study may be useful in clarifying issues in the management of other, similar agencies.

Canada↗
PubMed1995

Occupational injuries in Alberta: responding to recent trends.

General patterns of injury in the Alberta workplace are reflected in figures from the Workers' Compensation Board, which reliably enumerates acute injuries but not necessarily chronic musculoskeletal conditions. Roughly one-quarter of these injuries are to the back and neck. The absolute number of injuries is of interest in terms of the overall problem of injury in the workplace, but the rate of injury is used to set priorities for intervention among industries. The injury rate identifies industries at greatest risk given the size and activity of their workforce. Using rates, industries can be classified as high or low risk. Over time, claim rates for the major industrial sectors have been fairly stable. Rates from 1987 and 1988 were used in setting provincial government initiatives to control injury frequency and severity and are examined in this report. Construction is clearly a high-risk industry. It involves many trades and operations that have an inherently high risk. The situation is different for the manufacturing sector. This also has a very high injury experience. However, unlike construction, the risk is concentrated in one sub-industry-meat and poultry packing. As a single sector, oil and gas has a low risk. When the industry is broken down into its component functions, however, the oil and gas exploration, drilling and servicing components are clearly out of line with the rest of the sector. Risk is highly concentrated in these sub-industries. Data from Alberta confirm that smaller employers generally have a higher injury risk than larger employers.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents, Occupational↗
PubMed1995

Occupational health in China: 'rising with force and spirit'.

Occupational health services in China occupy a much more central role in public life than they do in North America. The Communist ideology on which the People's Republic was built, and which it almost alone today defends, places an idealized concept of the worker at the centre of the economic, social and political system. The present system in China is a parallel, institutionally separate system of medical care and research on occupational disorders that is in some ways better provided for with resources than the general healthcare system. One of the issues facing China today is how to turn the priorities of this vast, elaborate and incompletely developed system of occupational health care away from the provision of medical care to workers made ill from workplace exposure and towards prevention of the exposures that made them ill in the first place. The prevalence of smoking and the intensity of passive smoke exposure in Chinese workplaces make this exposure one of the most deadly occupational hazards seen. This problem of health promotion can probably only be effectively approached in China by worksite programmes but these are not apparent.

China↗
PubMed1995

Occupational mortality among firefighters: assessing the association.

Because of their occupational exposure to a variety of toxic agents, fire fighters may be at risk for a number of exposure-related diseases. We reviewed the current literature on disease risk among fire fighters to compare findings and to infer magnitude of risk. A standard mortality ratio (SMR) of 200 is equal to an attributable risk of 100% of expected, sufficient to justify presumption in most workers' compensation systems that accept this. We therefore concentrated on risks that approach or exceed an SMR of 200 or an equivalent risk estimate, bearing in mind that confidence intervals around these estimates are wide. Based on the criteria for presumption of occupational risk, we suggest the following conclusions with respect to general presumption of risk: (1) Lung cancer: There is evidence for an association but not of sufficient magnitude for a general presumption of risk. (2) Cardiovascular. There is no evidence for an increased risk of death overall from heart disease. Sudden death, myocardial infarction, or fatal arrhythmia occurring on or soon after near-maximal stress on the job are likely to be heart related, but such "heart attacks" occurring away from work cannot be presumed to be work related. (3) Aortic aneurysm: The evidence is incomplete for an association, but if an association does exist, it would probably be of a magnitude compatible with a general presumption of risk. (4) Cancers of the genitourinary tract, including kidney, ureter, and bladder: The evidence is strong for both an association and for a general presumption of risk. (5) Cancer of brain: Incomplete evidence strongly suggests a possible association at a magnitude consistent with a general presumption of risk. (6) Cancer of lymphatic and hematopoietic tissue: By group, there is some evidence for both an association and a general presumption or risk. However, the aggregation is medically meaningless. We therefore recommend a case-by-case approach. (7) Cancer of the colon and rectum: There is sufficient evidence to conclude that there is an association but not that there is a general presumption of risk. (8) Acute lung disease: Unusual exposures, such as exposure to the fumes of burning plastics, can cause severe lung toxicity and even permanent disability. This does not appear to result in an increased lifetime risk of dying from chronic lung disease.

Cardiovascular Diseases↗
PubMed1994

Lung cancer among tin miners in southeast China: silica exposure, silicosis, and cigarette smoking.

The Dachang Tin Mine is an industrial facility with high rates of lung cancer compared to the resident population in Guangxi province in southern China. Historically, exposure to silica dust was very high in the 1950s, falling in recent years to levels in keeping with international standards. Radon levels in the mine are low. We report the findings of a case-control study nested into a cohort study on miners working in Dachang. Cases of lung cancer among miners incident from 1973-1989 were obtained from local comprehensive medical records covering workers employed at the mine. These were matched approximately 3 to 1 with miners randomly chosen from the district surrounding the mine within the same birth decade. Matched odds ratios of 2.42 (95% confidence limit [CL] 1.3, 4.4) for underground employment, 3.52 (95% CL 1.7, 7.5) for smoking, and 2.04 (95%) CL 1.2, 3.7) for silicosis as determined on chest film were noted. Multifactor analysis of unconditional logistic regression showed that among the risk factors for excess mortality from lung cancer only the years spent drilling underground and the cumulative smoking index (product of daily cigarette consumption and number of years smoking) were independent contributors to risk and there was no interaction observed. The presence of silicosis did not contribute to predicting risk independently of the years spent underground.

Case-Control Studies↗
PubMed1994

Occupational exposure to hydrogen sulfide in the sour gas industry: some unresolved issues.

Occupational exposure to hydrogen sulfide (H2S) and the medical management of H2S-associated toxicity remains a problem in the sour gas industry and some other industrial settings. The acute effects of exposure to H2S are well recognized, but accurate exposure-response data are limited to acutely lethal effects, even in animal studies. Odor followed by olfactory paralysis and keratoconjunctivitis are the characteristics effects of H2S at lower concentrations. H2S-induced acute central toxicity leading to reversible unconsciousness is a "knockdown"; it is controversial whether repeated or prolonged knockdowns are associated with chronic neurologic sequelae but the evidence is suggestive. Knockdowns can be acutely fatal as a consequence of respiratory paralysis and cellular anoxia. Pulmonary edema is also a well-recognized acute effect of H2S toxicity. Human studies of sublethal exposure with satisfactory exposure assessment are almost nonexistent. There are indications, poorly documented at present, of other chronic health problems associated with H2S exposure, including neurotoxicity, cardiac arrhythmia, and chronic eye irritation but apparently not cancer. Rigorous and comprehensive studies in the sour gas industry are difficult, in part because of confounding exposures and uncertain end points.

Air Pollutants, Occupational↗
PubMed1994

Personal exposure to pesticide among workers engaged in pesticide container recycling operations.

Pesticide container handling operations in western Canada were examined to determine the exposure of workers to residual pesticide in sorting, metal-container crushing, metal-container shredding, plastic-container shredding, metal washing, and metal melting. Environmental exposure monitoring and biological monitoring were applied, including measurement of pesticide deposition density on outer clothing (test coveralls and other protective wear), deposition on fabric and gauze patches under the outer clothing, inhalation of airborne pesticide residues, dislodgement of pesticide residues by hand washing, and pre- and postexposure urinary excretion of pesticide (2,4-D). Exposure levels were highly variable; some variability was accounted for by work practices or lapses in protection. The highest levels of exposure were observed for metal washing, metal crushing, and metal shredding; sorting and plastic shredding were intermediate, and metal melting was associated with very little exposure. Urinary 2,4-D excretion, as an indicator of internal dose, correlated most closely with exposure by the inhalation route, and both were highest for metal washing and shredding. Deposition of pesticide on garments was highest for metal crushing. Melting of washed metal does not appear to present a significant hazard of exposure. Recommendations are proposed for the protection of workers emphasizing health and safety guidelines, worker education, personal hygiene, exposure and health monitoring, and record-keeping, and specific recommendations for each process. These recommendations apply to all pesticide container recycling operations except melting of washed metal containers.

Alberta↗
PubMed1994

Voices of leadership in a community under stress: personal observations by officials on an epidemiologic mistake.

We studied the responses of leaders in a suburban community in western Canada near Edmonton, Alberta, that was affected by a false allegation of increased cancer risk. In 1986, a cancer agency responded to community concerns by conducting a study of cancer incidence (1979-1983) and reported elevations on the order of 25 per cent over expected for most sites. Reanalysis of these data several months later revealed an error in the population figure used to calculate the rates. Correction brought the rates into line with Alberta as a whole and comparable to those for other communities surrounding Edmonton. We interviewed elected and appointed public officials in one affected community as well as non-official community leaders and realtors to determine their subjective impression regarding the effect of the incident on their communities and to rule out alternative explanations for the drop in housing prices in association with the incident we have reported elsewhere. Their narrative responses were particularly interesting and articulate, and are quoted at length. Their collective perceptions appear to confirm the impression of a profound impact on the community, reflected in housing prices, and attribute at least part of the impact to the disclosure that a high official in the community was afflicted by cancer. Most felt that there remained a great deal of latent concern in the community and at least some felt that a subsequent public issue involving transmission line rights-of-way near the community reactivated this latent concern.

Adult↗
PubMed1994

Consistency of diagnostic criteria for asthma from Laënnec (1819) to the National Asthma Education Program (1991).

Interpretation of longitudinal trends in asthma incidence, prevalence, and mortality must assume consistency in the diagnostic criteria used by clinicians. This review samples the textbook and clinical literature on clinical recognition and diagnosis of asthma from Laënnec (1819) to the National Asthma Education Program (1991), which introduced as a standard for clinical care a set of diagnostic criteria based on laboratory confirmation. There is great consistency among authors in descriptions of the cardinal diagnostic criteria of asthma as episodic dyspnea punctuating periods of normal breathing, generally associated with expiratory wheezing and prolonged expiration. In contrast, there is much greater variation in the formal definitions or explanations of the presumed pathophysiology of the disorder. It is much more difficult to document the actual diagnostic criteria used by practicing clinicians in the past, but these findings indicate a high degree of consistency over 172 years in what was taught and was considered acceptable practice. The literature on asthma contains several medical classics, a few gems of insight, and some unusual authors; some of these are noted in the discussion, as is the strong tradition of reciprocity in American and British medicine.

Asthma↗
PubMed1994

Mortality from airways disorders in Alberta, 1927-1987: an expanding epidemic of COPD, but asthma shows little change.

Mortality from asthma has been reported to be increasing in recent years in many countries, including Canada. Alberta, and the prairie provinces generally, appear to have an excess of deaths from asthma compared to other provinces. We studied mortality from asthma and from chronic obstructive pulmonary disease (COPD) generally in Alberta between 1927 and 1987 using a data set compiled and recorded from Alberta Vital Statistics to describe birth cohorts' age-specific mortality rates. We also present the distribution of deaths in the years since 1987. There was a clear and sustained increase in mortality from COPD since 1950 after age 40 but no evidence to support the proposition that deaths from asthma were increasing in recent years; more recent data from Alberta Vital Statistics show no sustained increase since 1987, either. There was great variability from year to year and sporadically increased rates in a given year that were not sustained. These transient increases were observed particularly among females aged 10-14, 15-19, and 25-29 and among males aged 15-19, 25-29, and 80-84; however, there were also comparable decreases in asthma mortality of similar magnitude during the same time period in different age groups or in the other sex in the age group 10-14. We conclude that there is no excess of deaths from asthma over those expected by historical trends in Alberta at the present time but that the smoking-related epidemic of deaths from COPD continues unabated. The "smoothness" and consistency of the mortality trends suggest that physicians certifying deaths from these causes are using implicit diagnostic criteria that have not changed abruptly.

Adolescent↗
PubMed1994

Critical science and the critique of technology.

Environmental and occupational epidemiology are in the tradition of "critical science." Critical science is a mode of science in which scientific methods are used to critique the adverse consequences of technological development. Critical science should be explicitly recognized as a paradigm in interdisciplinary research. It is the "mode" in which environmental and occupational epidemiology function and the role that these and related disciplines play in society. As the feedback to society on the performance of technology, critical science has assumed a major role in modern society by providing an acceptable critique of technological development. The close association between scientific research and technology of the last three and one-half centuries has been the exception to the historical rule. Intelligent guidance of technology in modern society makes public participation and education in scientific, biomedical, and technical affairs imperative. Critical science in its interdisciplinary dimension is imperative to this public process. Truly interdisciplinary work can only be accomplished when the disciplinary underpinnings are strong and when individual investigators are encouraged to pursue their individual priorities. Critical science is no exception and requires encouragement of skepticism on the part of the investigator toward conventional assumptions.

Ecology↗
PubMed1994

Comparing environmental risks: a consultative approach to setting priorities at the community level.

Environmental risk management is facing a crisis. The number of recognized environmental hazards has clearly outstripped the resources available to do detailed studies on each or to establish effective control measures for each on an individual basis. Some method of prioritizing environmental hazards is required that does not involve detailed and individualized quantitative risk assessment. An alternative approach that has gained favour in recent years has been "risk comparison", as sponsored by the U.S. Environmental Protection Agency and as applied in several American states and local communities. Risk comparison is an approach that involves expert panels and the interested public in a consultative and iterative process leading to widespread agreement, if not consensus, on the relative rankings of often disparate environmental hazards. An outline of steps in the process formulated by the Northeast Center for Comparative Risk at the Vermont Law School is presented with commentary regarding its applicability to the Canadian scene. Implicit tradeoffs in risk comparison are also explored, including emphasis on categorical hazards v. media quality, magnitude of hazard v. population affected, ecological integrity v. human health, social concern v. scientific assessment, and novel v. familiar hazards. In practice, risk comparison is a process-oriented and often tedious approach, but it represents one way out of the current conundrum in dealing with environmental hazards.

Canada↗
PubMed1994

Basic clinical skills in occupational medicine.

By incorporating the principles of occupational medicine into their practices, physicians can better help those patients with job-related disorders and can improve the management of patients whose non-work-related conditions have implications for their employment. This article focuses on occupational history, physical examination skills, investigation of work sites, risk assessment, screening and surveillance, fitness-to-work evaluations and disability assessment, administration, prevention, health education and general communication, and ethical issues.

Health Education↗