Historical Asbestos Measurements in Denmark—A National Database

Objectives: Due to the long lag-time for health outcomes, historical asbestos exposure measurements are valuable to support assessments of associated occupational health effects, and also to assess time trends and effects of preventive measures. Methods: Different sources of stored data were collated, assessed and refined to create a harmonized database on historical asbestos fibre concentrations measured in specific work tasks and different industries. The final database contains 9236 asbestos measurements from Danish workplaces collected from 1971 to 1997. Results: The geometric mean of asbestos concentrations in different occupations and tasks ranged from 0.003 to 35 fibres cm−3. Highest concentrations were registered during handling of asbestos products in the construction services during the period 1981–1997. Although all the measured asbestos exposures without the use of respiratory equipment by the worker in the period of 1971–1997 exceeded the current 8-h time-weighted average exposure limit of 0.1 fibres cm−3, the majority of samples collected in the earlier period of 1971 to 1980 did not exceed the exposure limit of 2 fibres cm−3, which was in place at the time. All exposure data obtained from 1980 and onwards were found to be one seventh of the mean fibre concentrations in the previous measurement period. The impact of time shows a clear exponentially decreasing trend-line. Conclusions: Despite limitations in coverage of different occupations and tasks associated with the inventoried historical asbestos measurements, the data are helpful to identify specific work scenarios within an industry, where relatively high asbestos exposure levels may still occur or have occurred from 1971 to 1997.

Study on the Law of Harmful Gas Release from Limnoperna fortunei (Dunker 1857) during Maintenance Period of Water Tunnel Based on K-Means Outlier Treatment

It is of great significance for air pollution control and personnel safety guarantee to master the release characteristics of harmful gases in the process of Limnoperna fortunei corruption. In view of the lack of research on the environmental pollution caused by the corruption of Limnoperna fortunei, a model experiment was designed to study the three harmful gases of NH3, H2S, and CH4 in the putrid process of Limnoperna fortunei by considering the density of Limnoperna fortunei and the time of leaving water. The results show that: (1) The recognition and processing of outliers based on wavelet decomposition and K-means algorithm can effectively reduce the standard deviation and coefficient of variation of the data set and improve the accuracy of the data set. (2) The variation of NH3 and H2S gas concentrations with the time of water separation satisfies polynomial linear regression (R2 > 99%). (3) At a density of 0.5–7.0 × 104 mussels/m2, the highest concentration of NH3 reached 47.9777–307.9454 mg/m3 with the increase in the density of Limnoperna fortunei and the extension of the time away from water, far exceeding the occupational exposure limit of NH3 of 30 mg/m3, potentially threatening human health and safety. The highest detection value of H2S concentration is 0.1909–5.0946 mg/m3, and the highest detection concentration of CH4 is 0.02%, both of which can be ignored.

Highly Efficient Candlelight Organic Light-Emitting Diode with a Very Low Color Temperature

Low color temperature candlelight organic light-emitting diodes (LEDs) are human and environmentally friendly because of the absence of blue emission that might suppress at night the secretion of melatonin and damage retina upon long exposure. Herein, we demonstrated a lighting device incorporating a phenoxazine-based host material, 3,3-bis(phenoxazin-10-ylmethyl)oxetane (BPMO), with the use of orange-red and yellow phosphorescent dyes to mimic candlelight. The resultant BPMO-based simple structured candlelight organic LED device permitted a maximum exposure limit of 57,700 s, much longer than did a candle (2750 s) or an incandescent bulb (1100 s) at 100 lx. The resulting device showed a color temperature of 1690 K, which is significantly much lower than that of oil lamps (1800 K), candles (1900 K), or incandescent bulbs (2500 K). The device showed a melatonin suppression sensitivity of 1.33%, upon exposure for 1.5 h at night, which is 66% and 88% less than the candle and incandescent bulb, respectively. Its maximum power efficacy is 23.1 lm/W, current efficacy 22.4 cd/A, and external quantum efficiency 10.2%, all much higher than the CBP-based devices. These results encourage a scalable synthesis of novel host materials to design and manufacture high-efficiency candlelight organic LEDs.

Exposure of cleaning workers to chemical agents and physical conditions in swimming pools and spas

Swimming pools and spas require a high hygiene level, and therefore constant cleaning. In this study, cleaning workers’ exposure to volatile organic compounds (VOCs), trichloramine (TCA), and particulate matter (PM) in the swimming pools and spas were evaluated. Also, statistical methods were employed to determine what activities affect the exposure to disinfection byproducts (DBPs). The study was conducted in 32 swimming pools and spas. The measurement locations were pool areas, bathrooms, and locker rooms, both during cleaning and opening hours. During the cleaning, the total volatile organic compound (TVOC) concentrations were low, on average 96, 251, and 91 µg/m3 for locker rooms, bathrooms, and pool areas, respectively. Similarly, during the opening hours, the TVOC concentrations were on average 78, 125, and 83 µg/m3, for locker rooms, bathrooms, and pool areas, respectively. This is in line with previous studies investigating cleaning work in other environments. The most prevalent compounds during the cleaning were 2-(2-butoxyethoxy)ethanol (DEGBE), 2-(2-ethoxyethoxy)ethanol (DEGEE), 2-butyl-1-octanol, trichloromethane (chloroform), decamethylcyclopentasiloxane (D5), and carbon tetrachloride. The most prevalent compounds during the opening hours were D5, D-limonene, carbon tetrachloride (bathrooms and pool areas), and trichloromethane (bathrooms and pool areas). The TCA concentrations during the cleaning in the bathrooms and pool areas were on average 60 and 67 µg/m3, respectively, and during the opening hours, 28 and 122 µg/m3, respectively. The use of disinfectants was found to increase the TCA concentration in the bathrooms, while the other cleaning products did not. Even though the TCA concentrations were below the WHO’s guideline and the Finnish occupational exposure limit value of 500 µg/m3, the measured TCA levels were occasionally high enough to pose a risk of irritative symptoms. The PM concentrations were low, both in the real-time monitoring (aerodynamic diameter, Dae ≤ 15 µm) and inhalable dust samples (Dae ≤ 100 µm). Highest measured inhalable dust concentration was 350 µg/m3, well below the Finnish occupational limit value of 5,000 µg/m3 for organic inhalable dust.

Coal mine dust lung disease in miners killed in the Upper Big Branch disaster: a review of lung pathology and contemporary respirable dust levels in underground US coal mines

ObjectivesIn 2010, 29 coal miners died due to an explosion at the Upper Big Branch (UBB) mine in West Virginia, USA. Autopsy examinations of 24 individuals with evaluable lung tissue identified 17 considered to have coal workers’ pneumoconiosis (CWP). The objectives of this study were to characterise histopathological findings of lung tissue from a sample of UBB fatalities and better understand the respirable dust concentrations experienced by these miners at UBB relative to other US coal mines.MethodsOccupational pulmonary pathologists evaluated lung tissue specimens from UBB fatalities for the presence of features of pneumoconiosis. Respirable dust and quartz samples submitted for regulatory compliance from all US underground coal mines prior to the disaster were analysed.ResultsFamilies of seven UBB fatalities provided consent for the study. Histopathologic evidence of CWP was found in all seven cases. For the USA, central Appalachia and UBB, compliance dust samples showed the geometric mean for respirable dust was 0.468, 0.420 and 0.518 mg/m3, respectively, and respirable quartz concentrations were 0.030, 0.038 and 0.061 mg/m3. After adjusting for quartz concentrations, UBB exceeded the US permissible exposure limit (PEL) for respirable dust in 28% of samples.ConclusionsAlthough higher than average respirable dust and quartz levels were observed at UBB, over 200 US underground coal mines had higher dust concentrations than UBB and over 100 exceeded the PEL more frequently. Together with lung histopathological findings among UBB fatalities, these data suggest exposures leading to CWP in the USA are more prevalent than previously understood.

Analysis of Process Safety and Occupational Health in Leather Process Industry: A Holistic Approach

Process Safety and Occupational health (PSOH) aspects in process industries are essential and need more consideration along with development in manufacturing and processing. In this regard, PSOH aspects are essential for the leather industry in order to prevent health hazards associated with it and improve upon adequate measures. Better safeguards and practices are necessary in PSOH for the benefit of not only for people working in the industry but for the environment at large. The situation is significant wherever hazardous chemicals or chemicals which could lead to compromise on safety in the workplace are involved. The degree of toxicity or hazard and exposure limit associated for some of them, inside factory premises are of major concern. In addition to the chemicals, other aspects such as dusts, noise levels, lighting, ergonomics, ventilation, personal safety and hygiene are worth considering. As mentioned above, the present paper analyzes various aspects of PSOH in leather process industries as a holistic approach.

PSXIII-18 The effect of lead on alkaline phosphatase serum activity in European carp

The aim of this research is to assess the toxic influence of heavy metals in fish. This study was intended to analyze alkaline phosphatase (AP) serum activity under the influence of various lead concentrations in European carp. AP is involved in the dephosphorylation processes and is an important indicator of liver and skeleton tissue metabolism. When exposed to heavy metals, a change in the activity of this enzyme can be observed. In this experiment 3 groups of fish (European carp) were formed, 10 fish in each group: control group; 1-experimental group – fish were contained in water with 0.06 mg/l lead acetate concentration (upper threshold level than fishery waters permissible exposure limit according to the laws of the Russian Federation); 2-experimental group – fish were contained in water with 0.6 mg/l lead acetate concentration (10 times higher than fishery waters permissible exposure limit according to the laws of the Russian Federation). Exposure time was 4 hours. The blood samplings were taken from heart by syringe and placed in dry test tubes. After samplings centrifugation in non-hemolysed serum samples AP activity was assessed. The study revealed the decreasing trend of AP serum activity by 1.08% (21.89±0.24 IU/l) in 1-experimental group in compare with control group (22.13±0.78 IU/l). In case where the lead acetate concentration were 10 times higher than fishery waters permissible exposure limit were meaningful decreasing of AP activity (P ≤ 0.05) by 66.23% (17.42±0.63 IU/l) accordingly in 2-experimental group in compare with control group. In conclusion, a statistically significant decrease in the AP activity in fish blood serum was found after acetate concentration 10 times higher than the permissible exposure limit in fishery waters, according to the laws of the Russian Federation. We can suppose that the activity of this enzyme is the reason for the inhibitory effect of lead on liver tissue.

An Interdisciplinary Framework for Derivation of Occupational Exposure Limits

Protecting the health and safety of workers in industrial operations is a priority of the utmost importance. One of the fundamental parameters relied upon to ensure worker safety is an occupational exposure limit (OEL), which is based on empirical data from animal or observational human studies. There are various guidelines for the derivation and implementation of OELs globally, with a range of stakeholders (including regulatory bodies, governmental institutions, various expert groups, etc) providing such guidance. The purpose of this manuscript is not to review or provide commentary on existing guidance, but rather to share our learnings from a multidisciplinary approach to the OEL derivation process (from problem formulation to uncertainty analysis). The technical assessment that is foundational to the development of a scientifically-derived OEL follows the same sequence of steps as other types of risk assessment: (1) problem formulation, (2) literature review, (3) weight of evidence considerations, (4) point of departure (PoD) selection/derivation, (5) application of assessment factors, and the final step, derivation of the OEL. This manuscript describes a technical framework by which available data relevant for occupational exposures is compiled, analyzed, and utilized to inform safety threshold derivation applicable to OELs.

Occupational Lead Exposure and Safety Measures at Shooting Ranges: a Systematic Review

Background: Individuals at shooting ranges are exposed to high amount of lead fumes either indoor or outdoor. The shooters sprayed lead dust into the air upon discharge of the cartridge at arm’s length distance. Most of the previous studies conducted at shooting ranges focused on blood lead levels (BLLs) of exposed people and there are limited studies on the risk associated with the shooting of firearms. This study aimed to review previous studies on the hazards associated with the discharge of firearms, and safety measures at shooting ranges. Methods: A systematic review was conducted to explore the available evidence. The databases were searched using the keywords “indoor shooting ranges”, “outdoor shooting ranges”, “firearms shooting”, “lead poisoning hazard”, “blood lead biomarkers”, “permissible exposure limit”, and “safety practice on lead”. Results: The designated BLL for case definition in lead poisoning was between 0.1μg/dL - 0.49μg/dL. It was estimated that at Permissible Exposure Limit (PEL). PEL of 0.5μg/m3, 95 percent of range users who are exposed to lead poisoning regularly can have BLL of <5μg/dL during 20 years of working life, while at 2.1μg/m3, 95 percent of the workers can have BLL of<10μg/dL during their working life. Conclusion: To protect firearm handlers and shooting range workers, policy on preventive measures should be implemented at shooting ranges by policymakers. Compliance with preventive measures is encouraged to avoid the high cost of rehabilitation lead poisoning.