Qualitative Exposure Assessment Research Articles

Hospital Bed for Diabetes Care: An Invention to Support Professional and Hygienic Nursing Practice

Appropriate diabetes mellitus (DM) wound care requires safe and comfortable space and facilities for patients and nurses. However, the existing hospital bed for DM has not supported the safety and comfort for nurses to serve patients, including the problem of liquid waste and some DM wounds emit a foul smell. Therefore, a hospital bed for DM wound care was designed in this research to support professional, efficient, ergonomic, and safe nursing practice. Multidisciplinary collaboration by engineers, wound nursing practitioners, and industry is carried out in this project. The level of risk of work disturbances was evaluated using a rapid entire body assessment (REBA), the level of risk of contamination was evaluated by a qualitative exposure assessment, and the level of comfort was measured using the visual analog method. Trials on 30 respondents consisting of 28 nurses and 2 doctors indicated that they were comfortable working with the new design of this prototype with lower risk.

Occurrences and ecotoxicological risks of trace metals in the San Benito Archipelago, Eastern Pacific Ocean, Mexico

Trace metal concentrations (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd, As, Hg) were determined in water, sediment and biota samples collected from the San Benito Islands off the Pacific Coast of Baja California, Mexico for a geochemical forensic study. Due to the proximity to the continental – oceanic crust interface and high biological endemism, the islands demanded a profound geochemical survey for evaluating the presence and provenance of trace metals. Results suggested that the metals in the region are mainly originated from the geogenic sources (Fe, Mn, Ni, Cr, Cu, Co), deep water circulation (Cd), atmospheric deposition (Pb) and hydrothermal processes (As). Dissolved phase is the major metal carrier of Pb with an average value of 0.182 mg L−1, while Fe (1.60%), Mn (335.42 mg kg−1), Ni (61.77 mg kg−1), Zn (32.36 mg kg−1) and Cr (28.7 mg kg−1) are mainly present in the particulate phase. High values of Pb, As, Cd and Hg in biota with no biological functions are highly toxic and are especially critical to those predators (Sea lions) in the region due to the process of biomagnification. For a qualitative exposure assessment of trace metals, several indices namely Heavy metal Evaluation Index (HEI), Nemerow Pollution Index (NPI), Bioconcentration Factor (BCF) and Biota Sediment Accumulation Factor (BSAF) were calculated. The indices revealed that the overall pollution status of the region is “moderate”. This study advocates a preliminary environmental surveillance in trace metal concentrations for implementing better conservation strategies in maintaining and promoting the ecological richness and endemism of the islands.

Using checklists and algorithms to improve qualitative exposure judgment accuracy

ABSTRACTMost exposure assessments are conducted without the aid of robust personal exposure data and are based instead on qualitative inputs such as education and experience, training, documentation on the process chemicals, tasks and equipment, and other information. Qualitative assessments determine whether there is any follow-up, and influence the type that occurs, such as quantitative sampling, worker training, and implementing exposure and risk management measures. Accurate qualitative exposure judgments ensure appropriate follow-up that in turn ensures appropriate exposure management. Studies suggest that qualitative judgment accuracy is low. A qualitative exposure assessment Checklist tool was developed to guide the application of a set of heuristics to aid decision making. Practicing hygienists (n = 39) and novice industrial hygienists (n = 8) were recruited for a study evaluating the influence of the Checklist on exposure judgment accuracy. Participants generated 85 pre-training judgments and 195 Checklist-guided judgments. Pre-training judgment accuracy was low (33%) and not statistically significantly different from random chance. A tendency for IHs to underestimate the true exposure was observed. Exposure judgment accuracy improved significantly (p <0.001) to 63% when aided by the Checklist. Qualitative judgments guided by the Checklist tool were categorically accurate or over-estimated the true exposure by one category 70% of the time. The overall magnitude of exposure judgment precision also improved following training. Fleiss’ κ, evaluating inter-rater agreement between novice assessors was fair to moderate (κ = 0.39). Cohen's weighted and unweighted κ were good to excellent for novice (0.77 and 0.80) and practicing IHs (0.73 and 0.89), respectively. Checklist judgment accuracy was similar to quantitative exposure judgment accuracy observed in studies of similar design using personal exposure measurements, suggesting that the tool could be useful in developing informed priors and further demonstrating its usefulness in producing accurate qualitative exposure judgments.

Exposure to thoracic aerosol in a prospective lung function study of cement production workers.

An exposure study was conducted as part of a multi-national longitudinal study of lung function in cement production workers. To examine exposure to thoracic aerosol among cement production workers during a 4-year follow-up period. Personal shift measurements of thoracic aerosol were conducted among the cement production workers within seven job types, 22 plants, and eight European countries (including Turkey) in 2007, 2009, and 2011. The thoracic sub-fraction was chosen as the most relevant aerosol fraction related to obstructive dynamic lung function changes. Production factors, job type, and respirator use were recorded by questionnaire. The exposure data were log-transformed before mixed models analysis and results were presented by geometric mean (GMadj) exposure levels adjusted for plant or job type, worker, and season as random effects. A total of 6111 thoracic aerosol samples were collected from 2534 workers. Repeated measurements were obtained from 1690 of these workers. The GMadj thoracic aerosol levels varied between job types from 0.20 to 1.2mg m(-3). The highest exposure levels were observed for production, cleaning, and maintenance workers (0.79-1.2mg m(-3)) and could reach levels where the risk of lung function loss may be increased. The lowest levels were found for administrative personnel (0.20mg m(-3)) serving tasks in the production areas. Office work was not monitored. GMadj exposure levels between plants ranged from 0.19 to 2.0mg m(-3). The time of year/season contributed significantly to the total variance, but not year of sampling. Production characteristics explained 63% of the variance explained by plant. Workers in plants with the highest number of employees (212-483 per plant) were exposed at a level more than twice as high as those in plants with fewer employees. Other production factors such as cement production, bag filling, and tidiness were significant, but explained less of the exposure variability. These determinants factors can be useful in qualitative exposure assessment and exposure prevention in the cement production industry. Respirator use was minor at exposure levels <0.5mg m(-3) but more common at higher levels. Production, cleaning, and maintenance work were the job types with highest exposure to thoracic aerosol in cement production plants. However, plant had an even larger effect on exposure levels than job type. The number of employees was the most important factor explaining differences between plants. Exposure reached levels where the risk of lung function loss may be increased. No significant differences in exposure between sampling campaigns were observed during the 4-year study period.

Exposure assessment for a cohort of workers at a former uranium processing facility

Exposure was assessed for a cohort of 6409 workers at a former uranium processing facility as part of a mortality study. Workers at the facility had potential for exposure to a wide variety of radiological and chemical agents including uranium, thorium, radon, external ionizing radiation, acid mists, asbestos, and various solvents. Organ dose from internal exposure to uranium was assessed, along with dose from external ionizing radiation and exposure to radon. Qualitative assessment of exposure to thorium, acid mists, asbestos, coal dust, welding fumes, and other chemicals was also performed. Mean cumulative organ dose from internal uranium exposure ranged from 1.1 mGy (lung) to 6.7 μGy (pancreas). Mean cumulative external ionizing radiation dose was 13.4 mGy. Mean cumulative radon exposure was 26 working level months (WLMs). The chemical agents to which the largest numbers of study subjects were exposed were acid mists, machining fluids, and a tributyl phosphate/kerosene mixture used in the refining process.

Inventory of the chemicals and the exposure of the workers’ skin to these at two leather factories in Indonesia

PurposeTannery workers are exposed to hazardous chemicals. Tannery work is outsourced to newly industrialized countries (NICs) where attention into occupational health hazards is limited. In this study, we investigated the skin exposure to hazardous chemicals in tannery workers and determined the prevalence of occupational skin diseases (OSDs) at tanneries in a NIC.MethodsA cross-sectional study on the observation of the working process and an inventory and risk assessment of the chemicals used. Classification of chemicals as potential sensitizers/irritants and a qualitative assessment of exposure to these chemicals. Workers were examined and interviewed using Nordic Occupational Skin Questionnaire-2002/LONG.ResultsThe risk of OSDs at the investigated tanneries was mainly related to the exposure of the workers’ skin to chemicals in hot and humid environmental conditions. In 472 workers, 12% reported a current OSD and 9% reported a history of OSD. In 10% of all cases, an OSD was confirmed by a dermatologist and 7.4% had an occupational contact dermatitis (OCD). We observed that personal protective equipment (PPE) used was mainly because of skin problems in the past and not as a primary protection against OSD.ConclusionWe observed a high frequency and prolonged exposure to many skin hazardous factors in tannery work although PPE was relatively easily available and which was generally used as a secondary preventative measure. The observed point-prevalence in this study was at the same level as that reported for other high-risk OSDs in Western countries and other tanneries in NICs. However, the observed point-prevalence in this study was lower than that reported in India and Korea. The results of our study and those of other studies at tanneries from other NICs were probably influenced by Healthy Worker Survivor Effect (HWSE).

SIRAD – Personal radiation detectors

Abstract SIRAD badge dosimeters provide a visual qualitative measurement of exposure to radiation for mid range dose exposure. This is performed using an active radiochromic dosimeter in a transparent window, combined into a badge assembly. When irradiated, the badges active window turns blue, which can be matched against the given colour chart for a qualitative assessment of the exposure received. Two peaks in the absorption spectra located at 617 nm and 567 nm were found. When analysed with a common computer desktop scanner, the optical density response of the film to radiation exposure is non-linear but reproducible. The net OD of the film was 0.21 when exposed to 50cGyand 0.31 at 200 cGy exposure when irradiated with a 6 MV x-ray energy beam and analysed using a broad spectrum light source. These values reduced when exposed with kilovoltage x-rays with an approximate 30% reducing in sensitivity at 50 kVp. The film provides an adequate measurement and visually qualitative assessment of radiation exposure for levels in the range of 0–50 cGy.

THE MEASUREMENT AND DISTRIBUTION OF WOOD DUST

In Italy, the woodworking industry presents many issues in terms of occupational health and safety. This study on exposure to wood dust could contribute to the realization of a prevention model in order to limit exposure to carcinogenic agents to the worker. The sampling methodology illustrated the analysis of dust emissions from the woodworking machinery in operation throughout the various processing cycles. The quantitative and qualitative assessment of exposure was performed using two different methodologies. The levels of wood dust were determined according to EN indications and sampling was conducted using IOM and Cyclon personal samplers. The qualitative research of wood dust was performed using an advanced laser air particle counter. This allowed the number of particles present to be counted in real time. The results obtained allowed for an accurate assessment of the quality of the dust emitted inside the workplace during the various processing phases. The study highlighted the distribution of air particles within the different size classes, the exact number of both thin and ultra-thin dusts, and confirmed the high concentration of thin dust particles which can be very harmful to humans.

Feathers as bioindicators of PCB exposure in clapper rails

In this study we used feathers to biomonitor exposure to the polychlorinated biphenyl (PCB) Aroclor 1268 congener mixture in clapper rails (Rallus longirostris). This species has been used as an indicator species of environmental damage for the LCP superfund site located in Brunswick, GA, USA which is contaminated with Aroclor 1268, a congener mixture that has been used in limited amounts elsewhere and therefore can be used as a contaminant marker. The Aroclor 1268 congener mixture, including congener profiles, were quantified in feathers using gas chromatography (GC). Concurrently, each sample was quantified for the total Aroclor 1268 congener mixture using an enzyme-linked immunosorbant assay (ELISA) and compared to the GC results to determine if ELISA was an efficient method for quantifying or qualifying PCBs in feathers. ELISA consistently quantified PCB loads over an order of magnitude lower than the GC. Based on sample replication, extraction recovery, and sample spike, it appears that GC is the more reliable method of detection and that ELISA methods may be more suitable for qualitative exposure assessment for this particular Aroclor. Moreover, since all clapper rails from the LCP site had the Aroclor 1268 congener mixture in their feathers, this experiment showed that birds were returning to the site to breed despite the adverse effects experienced by this population from the contamination revealed in previous studies. This study also supports the utility of feathers as a non-lethal mechanism by which to biomonitor PCBs in the environment.

Mortality among Former Love Canal Residents

BackgroundThe Love Canal is a rectangular 16-acre, 10-ft deep chemical waste landfill situated in a residential neighborhood in Niagara Falls, New York. This seriously contaminated site first came to public attention in 1978. No studies have examined mortality in the former residents of the Love Canal neighborhood (LC).ObjectiveThe aim of this study was to describe the mortality experience of the former LC residents from the years 1979–1996.MethodsFrom 1978 to 1982, 6,181 former LC residents were interviewed. In 1996, 725 deaths from 1979–1996 were identified in this cohort, using state and national registries. We compared mortality rates with those of New York State (NYS) and Niagara County. Survival analysis examined risks by potential exposure to the landfill.ResultsWe were unable to demonstrate differences in all-cause mortality for either comparison population for 1979 1996. Relative to NYS, the standardized mortality ratio (SMR) was elevated [SMR = 1.39; 95% confidence interval (CI), 1.16–1.66] for death from acute myocardial infarction (AMI), but not relative to Niagara County. Death from external causes of injury was also elevated relative to both NYS and Niagara County, especially among women (SMR = 1.95; 95% CI, 1.25 2.90).ConclusionsThe role of exposure to the landfill in explaining these excess risks is not clear given limitations such as multiple comparisons, a qualitative exposure assessment, an incomplete cohort, and no data on deaths prior to 1978. Lack of elevation for AMI when compared with Niagara County but not NYS suggests possible regional differences. However, direct cardiotoxic or neurotoxic effects from landfill chemicals or indirect effects mediated by psychological stress cannot be ruled out. Revisiting the cohort in the future could reveal patterns that are not yet apparent.

Quantitative and Qualitative Assessment of Exposure among Employees in Norwegian Smelters

To generate a job exposure matrix (JEM) for dust exposure in Norwegian smelters to be used in an epidemiologic study of respiratory diseases and to identify determinants of exposure. The arithmetic mean and geometric mean (GM) of 2619 personal dust exposure measurements were applied in constructing the JEM, which was assigned to 2620 employees participating in a respiratory survey including yearly spirometry and a respiratory questionnaire. A qualitative exposure classification was constructed: (i) line operators were those employed full time in the production line, (ii) non-exposed employees were those who did not work in production and (iii) the remainder were classified as non-line operators. In the ferrosilicon alloy and silicon metal production group (FeSi/Si-metal), the median GM of dust exposure was 2.3 mg m(-3) (0.04-5.6) (10-90% percentiles) compared with 1.6 mg m(-3) (0.02-2.3) in the silicomanganese, ferromanganese and ferrochromium production group (SiMn/FeMn/FeCr). Multivariate analyses showed that dust exposure concentration levels decreased significantly with increasing age (FeSi/Si-metal), was significantly lower in females than in males and was significantly higher in current smokers than in never-smokers. Dust exposure concentration levels were also higher in employees reporting previous exposure to dust, fumes and gases than in employees without such previous exposure, though, significant only in the FeSi/Si-metal production group. The dust exposure levels of the employees were higher in the FeSi/Si-metal production group than in the SiMn/FeMn/FeCr production group. Age, gender, smoking status and previous exposure were significant determinants of dust exposure and should be evaluated in future analyses of the relationship between health outcomes and dust exposure in this industry.

Qualitative exposure assessment for Salmonella spp. in shell eggs produced on the island of Ireland

A qualitative exposure assessment for Salmonella in eggs produced on the island of Ireland was developed. The assessment was divided into three main modules (production and packing, distribution and storage, and preparation and consumption), and each of these stages into defined steps in the exposure pathway. In the production and packing stage the initial prevalences of Salmonella in the contents and on the shell of eggs were estimated to be negligible and low respectively. Numbers of Salmonella both in and on eggs were estimated to be low. At each subsequent step in the pathway, qualitative assessments were made of the impact of events on the probability and level of Salmonella contamination on the shells and in the contents of eggs. At the end of each module assessments were combined to give an overall probability and level of Salmonella contamination. In the first two modules the assessment focused on the effect of the duration and temperature of storage on yolk membrane integrity and the likelihood of shell penetration. During the final stage the influence of factors such as safe-handling procedures, pooling practices, consumption patterns and the effectiveness of cooking, on the prevalence and level of Salmonella contamination in a food item at time of consumption was assessed. The outcome of this assessment was an estimate of a low probability and level of Salmonella contamination of egg-containing foods, prepared with eggs produced on the island of Ireland.

Evaluation of the Predictive Abilities of a Qualitative Exposure Assessment Model

Various qualitative exposure assessment models based on different underlying assumptions requiring distinct inputs and providing diverse outputs are used by occupational hygienists and risk managers to evaluate the magnitude of occupational exposures. Although a wide variety of exposure assessment models are available, most models have not been validated. This study compared the inhalation risk factor of a qualitative exposure assessment model with quantitative exposure data collected at a manufacturing facility for more than 9 years for 12 worker groups involving 24 chemical agents. A Spearman's rho correlation found no significant correlation between the model's risk factor and the maximum measured exposure (rs = 0.119, p = 0.496). A Fisher exact test found that the maximum measured exposure was independent of the model's inhalation risk factor (χ2 = 0.203, p = 0.653). The model accurately classified measured exposures in 18 out of 35 cases (51%), 53% of the measured exposures classified as acceptable were correctly classified by the model (sensitivity), whereas 33% of the measured exposures classified as uncertain/unacceptable were correctly classified by the model (specificity). There was a 67% probability that the model would result in a false low classification and a 47% probability that the model would result in a false high classification. Although the model was simple to apply, the overall predictive ability for the low level exposures seen in the study were poor and inconsistent among worker groups compared.

Visible absorption spectra of radiation exposed SIRAD dosimeters

SIRAD badge dosimeters are a new type of personal dosimeter designed to measure radiation exposure up to 200 R and give a visual qualitative measurement of exposure. This is performed using the active dosimeter window, which contains a radiochromic material amalgamated in the badge assembly. When irradiated, the badges active window turns blue, which can be matched against the given colour chart for a qualitative assessment of the exposure received. Measurements have been performed to analyse the absorption spectra of the active window, and results show that the window automatically turns a blue colour upon irradiation and produces two peaks in the absorption spectra located at 617 nm and 567 nm. When analysed with a common computer desktop scanner, the optical density response of the film to radiation exposure is non-linear but reproducible. The net OD of the film was 0.21 at 50 R exposure and 0.31 at 200 R exposure when irradiated with a 6 MV x-ray energy beam. When compared to the calibration colour strips at 6 MV x-ray energy the film's OD response matches relatively well within 3.5%. An approximate 8% reduction in measured OD to exposure was seen for 250 kVp x-rays compared to 6 MV x-rays. The film provides an adequate measurement and visually qualitative assessment of radiation exposure for levels in the range of 0 to 200 R.

Bladder cancer among chemical workers exposed to nitrogen products and other substances.

To investigate further bladder cancer mortality excess based on four deaths observed among the internal comparison population of a previous historical cohort study of workers from a chemical plant in Lima, Ohio. The internal population mainly comprised workers from the Nitrogen Products (NP) Division. The original Lima cohort was expanded to include all workers (n = 1,841) employed between 1955 and 1996. A subcohort of workers employed mainly in the NP Division (NP Subcohort) was identified and used as the primary study population and as the source of cases and controls for a matched case-control study of bladder cancer. All death records were reviewed for any mention of bladder cancer; all available personnel, medical, and insurance files were reviewed to identify any current or former employees with an existing diagnosis of bladder cancer. A qualitative exposure assessment of all cases and controls was performed to evaluate an exploratory hypothesis that the bladder cancer excess may be associated with work histories involving both NP and urea, specifically, nitric acid and urea. We identified 96 new deaths among the expanded Lima cohort and obtained cause of death for 90. One additional bladder cancer death and one living case were identified and these were members of the original Lima cohort. The bladder cancer standardized mortality ratio (SMR) for the NP Subcohort (SMR = 3.31, 95%CI = 0.90-8.47) fell between the SMRs observed for all workers in the original and expanded Lima cohort (SMR = 3.93, 95%CI = 1.07-10.06 and 3.10, 95%CI = 1.01-7.24, respectively), but was markedly less than the SMR observed for corresponding subcohort of AN-unexposed workers in the original Lima cohort (SMR = 7.01, 95%CI = 1.91-17.96). Sparse data and a high prevalence of exposure among controls precluded an informative statistical analysis of the possible association between work histories involving both nitric acid and urea and bladder cancer risk. This study confirms that bladder cancer mortality is elevated among persons who worked mainly in the NP Division of the Lima plant, but at a lower, less statistically significant level than indicated by the original cohort study. No occupational risk factors considered to be causally related to the bladder cancer excess could be identified by this intensive investigation; other possible reasons for the excess are suggested by the descriptive data.

Assessment of exposure to chemical agents and ergonomic stressors in tanneries in Kanpur, India.

In developing countries qualitative assessment of exposure at the workplace may be an essential tool in evaluating hazardous working conditions. This survey reports on qualitative assessment of exposure to chemicals, dust, and ergonomic stressors among 298 workers in 15 tanneries in Kanpur, India. In general, chemical exposure and dermal exposure were highest among beamhouse workers, less for workers involved in dry finishing activities, and lowest for those performing the wet finishing of hides. Dermal exposure was rated as high to very high during beamhouse activities, reflecting direct contact with wet hides and manual handling of hides in soak tanks. Relevant dust exposure was observed only during dry finishing activities. Most workers experienced severe postural load due to working in trunk flexion and rotation for more than 50% of their daily work time. In addition, manual materials handling with loads over 20 kg frequently occurred. The size of the tannery, in general a reflection of state of technology, showed no systematic influence on exposure profiles. The survey suggested that mechanization of material transfer and application of trolleys reduced the work time with trunk flexion and rotation and implied less manual lifting. The presence of local exhaust ventilation in large tanneries seemed to reduce the chemical exposure. This survey has demonstrated the importance of rapid appraisal techniques for evaluating hazardous conditions at the workplace. In developing countries this approach may facilitate occupational hygiene research and practice.