Susan Sama

A field investigation of the acute respiratory effects of metal working fluids. II. Effects of airborne sulfur exposures.

A study of cross-shift change in pulmonary function was conducted among workers exposed to metal working fluids (MWF) in an automobile parts manufacturing company. Three hundred eighty-six workers (216 machinists exposed to straight or soluble MWFs, and 170 nonmachinists) were studied for 1 day, performing spirometry at the beginning and end of their shift. Airborne concentrations of inhalable particulate, culturable bacteria, and endotoxin were measured. We observed an approximately threefold increase in the incidence of 5% or greater cross-shift decrement in forced expiratory volume during the first second among those with exposures above about 0.15 mg/m3, compared to those with exposures below about 0.08 mg/m3. There was some evidence that chronic respiratory symptoms were more prevalent among machinists than among nonmachinists, notably for chronic cough. Baseline FEV1 was about 3% lower on average among those with soluble MWF exposure compared to nonmachinists. These findings are consistent with earlier studies showing respiratory effects of MWFs.

Sharps Injuries and Other Blood and Body Fluid Exposures Among Home Health Care Nurses and Aides

OBJECTIVES We quantified risks of sharp medical device (sharps) injuries and other blood and body fluid exposures among home health care nurses and aides, identified risk factors, assessed the use of sharps with safety features, and evaluated underreporting in workplace-based surveillance. METHODS We conducted a questionnaire survey and workplace-based surveillance, collaborating with 9 home health care agencies and 2 labor unions from 2006 to 2007. RESULTS Approximately 35% of nurses and 6.4% of aides had experienced at least 1 sharps injury during their home health care career; corresponding figures for other blood and body fluid exposures were 15.1% and 6.7%, respectively. Annual sharps injuries incidence rates were 5.1 per 100 full-time equivalent (FTE) nurses and 1.0 per 100 FTE aides. Medical procedures contributing to sharps injuries were injecting medications, administering fingersticks and heelsticks, and drawing blood. Other contributing factors were sharps disposal, contact with waste, and patient handling. Sharps with safety features frequently were not used. Underreporting of sharps injuries to the workplace-based surveillance system was estimated to be about 50%. CONCLUSIONS Sharps injuries and other blood and body fluid exposures are serious hazards for home health care nurses and aides. Improvements in hazard intervention are needed.

Exposure Assessment for a Field Investigation of the Acute Respiratory Effects of Metalworking Fluids. I. Summary of Findings

The exposure assessment summarized here is part of an epidemiologic study of the acute respiratory health effects of metalworking fluid (MF) exposures. Exposures were measured as the inhalable concentrations of the MF aerosol, a variety of metals and elements, and endotoxin as well as the level of culturable bacteria in the aerosol size fraction less than 8 microns. Bulk samples of soluble MFs were tested for pH, mineral and tramp oil fraction, endotoxin, culturable bacteria, and lipopolysaccharide levels. The MF exposed workers had higher geometric mean inhalable aerosol exposures (0.181 mg/m3) than the MF unexposed workers (0.046 mg/m3). The MF exposed workers had higher geometric mean (GM) airborne culturable microbial counts (102 colony-forming units (CFU)/m3 for bacteria < 8 microns) than the unexposed workers (GM = 14 CFU/m3). Among the unexposed, Bacillus was the predominant airborne species, while among the exposed workers, Pseudomonas predominated. Exposed workers also had higher geometric mean airborne endotoxin levels (GM = 7.1 endotoxin units (EU)/m3) than the unexposed workers (GM = 1.9 EU/m3). Elemental concentrations of iron, chlorine, and sulfur were substantially higher among the exposed workers compared to the unexposed workers. For soluble metalworking fluids, the levels of bulk constituents were examined by three categories of time since the machine sump was refilled with fresh MF (< 4 days, 4-21 days, > 21 days). Univariate analyses of percent oil, pH, culturable bacteria, tramp oil percent, endotoxin, or fatty acid levels all showed no statistically significant changes in level over time.

Case-by-case assessment of adult-onset asthma attributable to occupational exposures among members of a health maintenance organization.

Objective: In a general population of employed persons with health insurance, what proportion of adult-onset asthma is caused by occupational exposures? Method: We conducted a 2-year prospective study to identify adult-onset asthma among health maintenance organization (HMO) members. Telephone interviews regarding occupational exposures, symptoms, medication use, and triggers were used to assess likelihood of work-related asthma for each case. Weighted estimating equations were used to adjust the proportion of asthma attributable to workplace exposures for factors associated with interview participation. Results: Overall, 29% (95% confidence interval, 25–34%) of adult-onset asthma was attributable to workplace exposures; 26% (21–30%) and 22% (18–27%) of cases had asthma attributable to occupational irritant and sensitizer exposures, respectively. Conclusions: Occupational exposures, including irritants, are important causes of adult-onset asthma.

The Validation of Work-related Self-reported Asthma Exacerbation

Objective: To determine the validity of work-related self-reported exacerbation of asthma using the findings from serial peak expiratory flow (PEF) measurements as the standard. Methods: Adults with asthma treated in a health maintenance organisation were asked to conduct serial spirometry testing at home and at work for 3 weeks. Self-reported respiratory symptoms and medication use were recorded in two ways: a daily log completed concurrently with the serial PEF testing and a telephone questionnaire administered after the PEF testing. Three researchers evaluated the serial PEF records and judged whether a work relationship was evident. Results: 95 of 382 (25%) working adults with asthma provided adequate serial PEF data, and 13 of 95 (14%) were judged to have workplace exacerbation of asthma (WEA) based on these data. Self-reported concurrent medication use was the most valid single operational definition, with a sensitivity of 62% and a specificity of 65%. Conclusions: A work-related pattern of self-reported asthma symptoms or medication use was usually not corroborated by serial PEF testing and failed to identify many people who had evidence of WEA based on the serial PEF measurements.

Occupational health of home care aides: results of the safe home care survey

Objectives In countries with ageing populations, home care (HC) aides are among the fastest growing jobs. There are few quantitative studies of HC occupational safety and health (OSH) conditions. The objectives of this study were to: (1) assess quantitatively the OSH hazards and benefits for a wide range of HC working conditions, and (2) compare OSH experiences of HC aides who are employed via different medical and social services systems in Massachusetts, USA. Methods HC aides were recruited for a survey via agencies that employ aides and schedule their visits with clients, and through a labour union of aides employed directly by clients or their families. The questionnaire included detailed questions about the most recent HC visits, as well as about individual aides’ OSH experiences. Results The study population included 1249 HC aides (634 agency-employed, 615 client-employed) contributing information on 3484 HC visits. Hazards occurring most frequently related to musculoskeletal strain, exposure to potentially infectious agents and cleaning chemicals for infection prevention and experience of violence. Client-hired and agency-hired aides had similar OSH experiences with a few exceptions, including use of sharps and experience of verbal violence. Conclusions The OSH experience of HC aides is similar to that of aides in institutional healthcare settings. Despite OSH challenges, HC aides enjoy caring for others and the benefits of HC work should be enhanced. Quantification of HC hazards and benefits is useful to prioritise resources for the development of preventive interventions and to provide an evidence base for policy-setting.

Identifying the Determinants of Viable Microorganisms in the Air and Bulk Metalworking Fluids

Exposure assessment was conducted for an epidemiologic study of the respiratory effects of exposure to metalworking fluids (MWF). As part of the study, airborne microorganisms were collected with a two-stage microbial impactor, and a sample of the bulk soluble MWF was collected from each machine sump, as well as information about the work environment. These data were then used to develop multivariate statistical models of the determinants bulk MWF and airborne microbial levels. Microbial concentrations in the bulk MWF ranged from 5 x 10(4) to 5 x 10(10) colony-forming units (CFU)/mL, with a geometric mean of 3.4 x 10(7) CFU/mL. The geometric mean airborne microbial level was 182 CFU/m3 (for particles size <8 microm) with a range of 1 to 8,308 CFU/m3. In modeling the determinants of bulk microorganisms, fluid-related factors were the most important characteristics associated with microbial levels, followed by process-related and environmental factors. The final full multivariate model predicted a significant reduction in bulk microbial levels by increasing pH of the fluid and reducing the amount of tramp oil leaking into the fluid. For the airborne microbial models, process-related factors were the major characteristics associated with microbial levels, followed by factors related to worker activities and environmental factors. The final full multivariate model predicted a significant control of airborne microorganisms by increasing worker distance from the machine, reducing the number of machines within 10 feet of the worker, decreasing the bulk microbial levels, and adding machine enclosures. These models can be used to prioritize nonbiocidal interventions to control microbial contamination of the bulk MWF and the air.

Understanding sharps injuries in home healthcare: The Safe Home Care qualitative methods study to identify pathways for injury prevention

BackgroundHome healthcare is one of the fastest growing sectors in the United States. Percutaneous injuries from sharp medical devices (sharps) are a source of bloodborne pathogen infections among home healthcare workers and community members. Sharps use and disposal practices in the home are highly variable and there is no comprehensive analysis of the system of sharps procurement, use and disposal in home healthcare. This gap is a barrier to effective public health interventions. The objectives of this study were to i) identify the full range of pathways by which sharps enter and exit the home, stakeholders involved, and barriers for using sharps with injury prevention features; and ii) assess the leverage points for preventive interventions.MethodsThis study employed qualitative research methods to develop two systems maps of the use of sharps and prevention of sharps injuries in home healthcare. Twenty-six in-depth interview sessions were conducted including home healthcare agency clinicians, public health practitioners, sharps device manufacturers, injury prevention advocates, pharmacists and others. Interview transcripts were audio-recorded and analyzed thematically using NVIVO qualitative research analysis software. Analysis of supporting archival material also was conducted. All findings guided development of the two maps.ResultsSharps enter the home via multiple complex pathways involving home healthcare providers and home users. The providers reported using sharps with injury prevention features. However, home users’ sharps seldom had injury prevention features and sharps were commonly re-used for convenience and cost-savings. Improperly discarded sharps present hazards to caregivers, waste handlers, and community members. The most effective intervention potential exists at the beginning of the sharps systems maps where interventions can eliminate or minimize sharps injuries, in particular with needleless treatment methods and sharps with injury prevention features. Manufacturers and insurance providers can improve safety with more affordable and accessible sharps with injury prevention features for home users. Sharps disposal campaigns, free-of-charge disposal containers, and convenient disposal options remain essential.ConclusionsSharps injuries are preventable through public health actions that promote needleless treatment methods, sharps with injury prevention features, and safe disposal practices. Communication about hazards regarding sharps is needed for all home healthcare stakeholders.

Outdoor Air Pollution and COPD-Related Emergency Department Visits, Hospital Admissions, and Mortality: A Meta-Analysis.

ABSTRACT A systematic literature review was performed to identify all peer-reviewed literature quantifying the association between short-term exposures of particulate matter <2.5 microns (PM2.5), nitrogen dioxide (NO2), and sulfur dioxide (SO2) and COPD-related emergency department (ED) visits, hospital admissions (HA), and mortality. These results were then pooled for each pollutant through meta-analyses with a random effects model. Subgroup meta-analyses were explored to study the effects of selected lag/averaging times and health outcomes. A total of 37 studies satisfied our inclusion criteria, contributing to a total of approximately 1,115,000 COPD-related acute events (950,000 HAs, 80,000 EDs, and 130,000 deaths) to our meta-estimates. An increase in PM2.5 of 10 ug/m3 was associated with a 2.5% (95% CI: 1.6–3.4%) increased risk of COPD-related ED and HA, an increase of 10 ug/m3 in NO2 was associated with a 4.2% (2.5–6.0%) increase, and an increase of 10 ug/m3 in SO2 was associated with a 2.1% (0.7–3.5%) increase. The strength of these pooled effect estimates, however, varied depending on the selected lag/averaging time between exposure and outcome. Similar pooled effects were estimated for each pollutant and COPD-related mortality. These results suggest an ongoing threat to the health of COPD patients from both outdoor particulates and gaseous pollutants. Ambient outdoor concentrations of PM2.5, NO2, and SO2 were significantly and positively associated with both COPD-related morbidity and mortality.

Studying home health care nurses and aides: Research design and challenges

Home health care (HHC) is growing rapidly and yet health and safety conditions of HHC clinicians are poorly understood. Study of this workforce presents unique challenges because it is decentralised, often part-time and mobile. As part of a larger project on sharps injuries and blood exposures in HHC, this paper addresses the challenges of recruiting a large cohort of HHC nurses and aides and describes novel cross-sectional survey methodology. Recruitment was conducted with cooperation from eight HHC agencies and two labour unions. Intensive personal contacts and a financial incentive (