Niels Koehncke

The Saskatchewan Farm Injury Cohort: rationale and methodology.

The Saskatchewan Farm Injury Cohort (SFIC) is a major new Canadian study that was developed to evaluate potential causes of injury among farmers and their family members. The cohort involves 2,390 farms and 5,492 farm people being followed over a two-year period. The article describes the rationale and methodology for the baseline and longitudinal components of this study. The SFIC is one of the first studies to apply population health theory to the modeling of risks for injury in a defined Canadian population. In doing so, the relative influence of several potential causes of farm injury, including physical, socioeconomic, and cultural factors, will be estimated. Study findings will inform the content and targeting of injury prevention initiatives specific to the farm occupational environment.

Endotoxin Exposure and Inflammation Markers Among Agricultural Workers in Colorado and Nebraska

The adverse respiratory effects of agricultural dust inhalation are mediated in part by endotoxin, a constituent of gram-negative bacterial cell walls. This study quantified personal work-shift exposures to inhalable dust, endotoxin, and its reactive 3-hydroxy fatty acid (3-OHFA) constituents among workers in grain elevators, cattle feedlots, dairies, and on corn farms. Exposures were compared with post-work-shift nasal lavage fluid inflammation markers and respiratory symptoms. Breathing-zone personal air monitoring was performed over one work shift to quantify inhalable dust (Institute of Medicine samplers), endotoxin (recombinant factor C [rFC] assay), and 3-OHFA (gas chromatography/mass spectrometry). Post-shift nasal lavage fluids were assayed for polymorphonuclear neutrophils (PMN), myeloperoxidase (MPO), interleukin 8 (IL-8), albumin, and eosinophilic cation protein (ECP) concentrations. The geometric mean (GSD) of endotoxin exposure (rFC assay) among the 125 male participants was 888 ± (6.5) EU/m3, and 93% exceeded the proposed exposure limit (50 EU/m3). Mean PMN, MPO, albumin, and ECP levels were two- to threefold higher among workers in the upper quartile of 3‐OHFA exposure compared to the lowest exposure quartile. Even numbered 3-OHFA were most strongly associated with nasal inflammation. Symptom prevalence was not elevated among exposed workers, possibly due to endotoxin tolerance or a healthy worker effect in this population. This is the first study to evaluate the relationship between endotoxins 3-OHFA constituents in agricultural dust and nasal airway inflammation. More research is needed to characterize the extent to which these agents contribute to respiratory disease among agricultural workers.

Determinants of agricultural injury: a novel application of population health theory

Objectives (1) To apply novel population health theory to the modelling of injury experiences in one particular research context. (2) To enhance understanding of the conditions and practices that lead to farm injury. Design Prospective, cohort study conducted over 2 years (2007–09). Setting 50 rural municipalities in the Province of Saskatchewan, Canada. Subjects 5038 participants from 2169 Saskatchewan farms, contributing 10 092 person-years of follow-up. Main measures Individual exposure: self-reported times involved in farm work. Contextual factors: scaled measures describe socioeconomic, physical, and cultural farm environments. Outcome: time to first self-reported farm injury. Results 450 farm injuries were reported for 370 individuals on 338 farms over 2 years of follow-up. Times involved in farm work were strongly and consistently related to time to first injury event, with strong monotonic increases in risk observed between none, part-time, and full-time work hour categories. Relationships between farm work hours and time to first injury were not modified by the contextual factors. Respondents reporting high versus low levels of physical farm hazards at baseline experienced increased risks for farm injury on follow-up (HR 1.54; 95% CI 1.16 to 1.47). Conclusions Based on study findings, firm conclusions cannot be drawn about the application of population health theory to the study of farm injury aetiology. Injury prevention efforts should continue to focus on: (1) sound occupational health and safety practices associated with long work hours; (2) physical risks and hazards on farms.

Endotoxin and Dust at Respirable and Nonrespirable Particle Sizes are not Consistent Between Cage- and Floor-Housed Poultry Operations

BACKGROUND Individuals engaged in work in intensive animal houses experience some of the highest rates of occupationally related respiratory symptoms. Organic dust and in particular endotoxin has been most closely associated with respiratory symptoms and lung function changes in workers. It has previously been shown that for intensive poultry operations, type of poultry housing [cage-housed (CH) versus floor-housed (FH)] can influence the levels of environmental contaminants. The goal of the study was to determine the differences in endotoxin and dust levels at different size fractions between CH and FH poultry operations. METHODS Fifteen CH and 15 FH poultry operations were sampled for stationary measurements (area) of dust and associated endotoxin. Fractioned samples were collected utilizing Marple cascade impactors. Gravimetric and endotoxin analysis were conducted on each of the filters. RESULTS When assessed by individual Marple stage, there was significantly greater airborne endotoxin concentration (endotoxin units per cubic meter) in the size fraction >9.8 μm for the FH operations whereas at the size fraction 1.6-3.5 μm, the CH operations had significantly greater airborne endotoxin concentration than the FH operations. Endotoxin concentration in the dust mass (endotoxin units per milligram) was significantly greater in the CH operations as compared to the FH operations for all size fractions >1.6 μm. As such, endotoxin in the respirable fraction accounted for 24% of the total endotoxin in the CH operations whereas it accounted for only 11% in the FH operations. There was significantly more dust in all size fractions in the FH operations as compared to the CH poultry operations. CONCLUSIONS There is more endotoxin in the presence of significantly lower dust levels in the respirable particle size fractions in CH poultry operations as compared to the FH poultry operations. This difference in respirable endotoxin may be important in relation to the differential respiratory response experienced by CH and FH poultry operation workers.

Pulmonary function reductions among potentially susceptible subgroups of agricultural workers in Colorado and Nebraska.

Objective: Organic dust inhalation has been associated with adverse respiratory responses among agricultural workers. We evaluated factors that may confer increased susceptibility to these health effects. Methods: We quantified personal work shift exposures to inhalable dust, endotoxin, and its 3-hydroxy fatty acid constituents, and evaluated changes in pulmonary function among 137 grain elevator, cattle feedlot, dairy, and corn farm workers. Results: Increased dust exposure was associated with work shift reductions in lung function. Although interpretation is limited because of small samples, a suggestion of stronger exposure–response relationships was observed among smokers, as well as workers reporting pesticide/herbicide application, asthma, or allergies, and those with genetic polymorphisms (TLR4) (Pinteraction ⩽ 0.05). Conclusions: A better understanding of factors leading to increased susceptibility of adverse respiratory outcomes is needed to optimize exposure reduction strategies and develop more comprehensive wellness programs.

The relationship between fatigue-related factors and work-related injuries in the saskatchewan farm injury Cohort Study†

BACKGROUND The objective was to examine the relationship between seasonal variations in sleep quantity and work-related injuries on Saskatchewan farms. METHODS A cross-sectional analysis of data from the Saskatchewan Farm Injury Cohort Study was conducted. Analyses were restricted to workers, aged ≥16 years. The primary outcome was work-related injury in the last year. Logistic regression models were used to identify associations between sleep quantity and farm injury. RESULTS After controlling for confounding variables peak production season sleep was not associated with increased odds of injury. However, those obtaining ≤5 hr sleep per night during non-peak production seasons had increased odds of injury (OR 2.42, 95% CI 1.04-5.59) compared with those sleeping ≥7 hr per night. CONCLUSIONS We identified that restricted sleep durations, in certain seasons, placed farmers, and farm workers at risk of injury. Agricultural injury intervention programs need to consider the role of seasonal-related variations in sleep on farm injury.

A community-based participatory research methodology to address, redress, and reassess disparities in respiratory health among First Nations

BackgroundTo date, determinants of respiratory health in First Nations people living on reserves and means of addressing and redressing those determinants have not been well established. Hence the Saskatchewan First Nations Lung Health Project (FNLHP) is a new prospective cohort study of aboriginal people being conducted in two First Nations reserves to evaluate potential health determinants associated with respiratory outcomes. Using the population health framework (PHF) of Health Canada, instruments designed with the communities, joint ownership of data, and based on the 4-phase concept of the First Nations Regional Longitudinal Health Survey, the project aims to evaluate individual factors, contextual factors, and principal covariates on respiratory outcomes. The objective of this report is to clearly describe the methodology of (i) the baseline survey that consists of two components, an interviewer-administered questionnaire and clinical assessment; and (ii) potential intervention programs; and present descriptive results of the baseline data of longitudinal FNLHP.MethodsThe study is being conducted over 5 years (2012–2017) in two phases, baseline and longitudinal. Baseline survey has been completed and consisted of (i) an interviewer-administered questionnaire-based evaluation of individual and contextual factors of importance to respiratory health (with special focus on chronic bronchitis, chronic obstructive pulmonary disease, asthma and obstructive sleep apnea), and (ii) clinical lung function and allergy tests with the consent of study participants. The address-redress phase consists of potential intervention programs and is currently being rolled out to address-at community level (via green light program and environmental study), and redress-at policy level (via obesity reduction and improved diagnosis and treatment of obstructive sleep apnea) the issues that have been identified by the baseline data.ResultsInterviewer-administered surveys were conducted in 2012–2013 and collected data on 874 individuals living in 406 households from two reserve communities located in Saskatchewan, Canada. Four hundred and forty six (51%) females and 428 (49%) males participated in the FNLHP.ConclusionsThe information from this project will assist in addressing and redressing many of the issues involved including the provision of adequate housing, health lifestyle practices, and in planning for health service delivery.

Three new cases of apparent occupational asthma in swine confinement facility employees

To the Editors: In a previous issue of the European Respiratory Journal , Dosman et al. 1 reported on four cases of occupational asthma in newly employed workers in the large, recently developed, swine production facilities in Saskatchewan (Canada). All were full-time employees and all developed symptoms suggestive of asthma within a short time of commencing employment. None of the cases had a history of asthma, allergy symptoms or previous exposure to indoor air contaminants of swine confinement facilities. Work in swine buildings has been associated with respiratory symptoms, reductions in mean and across-shift lung function values 2, and increased bronchial responsiveness 3, 4. Asthma has been reported in swine workers, but this has typically occurred in workers with lengthy employment 5, 6. Cases 1–3 in our initial report showed some reaction to …

Occupational health and safety regulations in the dairy industry

ABSTRACT The application of occupational health and safety (OHS) legislation in the dairy industry varies throughout the world. Generally there is no specific OHS legislation that applies to the dairy industry and mostly in countries the current OHS legislation applies to all workplaces with specific guidelines that apply to agricultural industries. The main difference between countries is in the application of OHS legislation specifically in relation to the size of the farms. In the USA, the OHS legislation, and therefore enforcement, does not, in most cases, apply to farms with less than 11 employees, whereas in other countries there is no minimum number of employees and in some cases such as the United Kingdom and Australia it covers all people who work on the farm. The other area of difference is in the use and publication of guidelines for the industry; some countries have a wide range of guidelines whereas other counties have few. Generally, this relates to the jurisdiction of the OHS legislation, which in several countries is not at a national level such as USA, Canada, and Australia. The main principal of OHS legislation is that all workplaces, including dairy farms, should be a safe and healthy place to work, and does not vary significantly between the countries reviewed even those with prescriptive legislation.

The Hierarchy of Control in the Epidemic of Farm Injury

ABSTRACT The application of the hierarchy of control (HOC) is a well-established approach to hazard reduction in industrial workplaces. However, it has not been generally applied in farm workplaces. The objective was to determine current practices of farmers in the context of a modified HOC, and the effect of these practices on farm injury outcomes. A self-reported mail survey of 1196 Saskatchewan farm operations was conducted in 2013. Selected survey questions were used as proxy measures of the farm owner-operator’s practices relevant to each of the six steps of increasing importance in a modified HOC: (1) hazard identification; (2) risk assessment; (3) personal protection; (4) administrative controls; (5) engineering controls; and (6) elimination of the hazard. Analysis used basic descriptive statistics and logistic regression to examine associations of interest. When four of the six HOC steps were adhered to, there was a significant protective effect: odds ratio (OR) = 0.32 (95% confidence interval [CI]: 0.14–0.74) for any injury and OR = 0.27 (95% CI: 0.07–0.99) for serious injury in the overall study population. For farm owner-operators utilizing four of the six steps in the modified HOC, there was a significant protective effect for any injury (OR = 0.30, 95% CI: 0.11–0.83). Although there is a considerable absence of use of elements of the HOC among farm operators, for farmers who adhere to these steps, there is a significant reduction in their risk for injury. Prevention strategies that embrace the practice of these principles may be effective in the control of farm workplace injury.