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Exposure to polycyclic aromatic hydrocarbons (PAHs) of high molecular weight from chimney soot can cause cancer among chimney sweepers. These sweepers may also be exposed to high concentrations of nanosized particles, which can cause significant inflammatory responses due to their relatively greater surface area per mass. In this study, the authors aimed to assess the exposure profiles of airborne personal exposure to gaseous and particulate PAHs, and real-time samples of the particle number concentrations (PNCs), particle sizes, and lung-deposited surface areas (LDSAs), for chimney sweepers in Norway. Additionally, the authors aimed to assess the task-based exposure concentrations of PNCs, sizes, and LDSAs while working on different tasks. The results are based on personal samples of particulate PAHs (n = 68), gaseous PAHs (n = 28), and real-time nanoparticles (n = 8) collected from 17 chimney sweepers. Samples were collected during a "typical work week" of chimney sweeping and fire safety inspections, then during a "massive soot" week, where larger sweeping missions took place. Significantly higher PAH concentrations were measured during the "massive soot" week compared to the "typical work week," however, the time-weighted average (TWA) (8-hr) of all gaseous and particulate PAHs ranged from 0.52 to 4.47 µg/m3 and 0.49 to 2.50 µg/m3, respectively, well below the Norwegian occupational exposure limit (OEL) of 40 µg/m3. The PNCs were high during certain activities, such as emptying the vacuum cleaner. Additionally, during 2 days of sweeping in a waste sorting facility, the TWAs of the PNCs were 3.6 × 104 and 7.1 × 104 particles/cm3 on the first and second days, respectively, which were near and above the proposed nano reference limit TWA value of 4.0 × 104 particles/cm3 proposed by the International Workshop on Nano Reference Values. The corresponding TWAs of the LDSAs were 49.5 and 54.5 µm2/cm3, respectively. The chimney sweepers seemed aware of the potential health risks associated with exposure, and suitable personal protective equipment was used. However, the PNCs reported for the activities show that when the activities change or increase, the PNCs' TWAs can become unacceptably high.

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Using an exposure chamber, we investigate the precision of the DustTrak DRX monitor by comparing its results to those obtained from taking traditional gravimetric samples of two stone minerals commonly used in asphalt and lactose powder. We also discuss the possibility of using real-time monitors such as DustTrak DRX for occupational exposure monitoring purposes. The results are based on 19 days of experiment, each day with measurements collected over 4 h. Compared to the gravimetric samples, the DustTrak DRX overestimated the PM2.5 and respirable dust concentrations, while it underestimated the total dust concentration by a factor of nearly two. However, the ratios, being done for more than one material, between the DustTrak DRX and the gravimetric sample readings varied daily and across the different exposure materials. Real-time sensors have the potential to excel at identifying exposure sources, evaluating the measured control efficiency, visualizing variations in exposure to motivate workers, and contributing to the identification of measures to be implemented to reduce exposure. For total dust, a correction factor of at least two should be used to bring its readings up to those for the corresponding gravimetric samples. Also, if the DustTrak DRX is used in the initial profiling of occupational exposure, the exposure could be considered acceptable if the readings are well below the occupational exposure limit (OELs) after correction. If the DustTrak DRX readings, after correction, is close to, or above, the accepted exposure concentrations, more thorough approaches would be required to validate the exposure.

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OBJECTIVE: Stone minerals are a partially ignored environmental challenge but a significant contributor to urban air pollution. We examined if short-term exposure to two stone minerals - quartz diorite and rhomb porphyry - commonly used in asphalt pavement would affect lung function, promote pulmonary inflammation, and affect bronchial reactivity differently. METHODS: Our randomized crossover study included 24 healthy, non-smoking young adults exposed to the stone minerals quartz diorite, rhomb porphyry, and control dust (lactose). Exposure occurred in an exposure chamber, in three separate 4-hour exposure sessions. Fractional exhaled nitric oxide (FeNO) and lung function were monitored before exposure, then immediately following exposure, and 4 and 24 hours after exposure. In addition, methacholine was administered 4 hours following exposure, and exhaled breath condensate (EBC) was collected before exposure, then immediately and 4 hours after exposure. EBC was analyzed for pH, thiobarbituric acid reactive substances (TBARS), intercellular adhesion molecule 1 (ICAM-1), interleukin-6 (IL-6), IL-10, P-Selectin, surfactant protein D (SP-D), and tumor necrosis factor-α (TNF-α). RESULTS: Our results showed significantly elevated concentrations of FeNO after exposure to quartz diorite compared to rhomb porphyry, suggesting that quartz diorite is more likely to trigger pulmonary inflammation after short-term exposure. Moreover, short-term exposure to rhomb porphyry was associated with a modest but statistically significant decline in forced vital capacity (FVC) compared to quartz diorite. CONCLUSION: These results emphasize that using stone material in asphalt road construction should be reconsidered as it may affect lung inflammation and lung function in exposed subjects.

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A large fraction of particulate matter (PM), especially PM10, concentrations are due to non-exhaust emissions, such as road abrasion and wear on tires and brake pads. Concentrating on road abrasion, we aimed to investigate blood coagulability in healthy adults after exposure to two types of stone materials commonly used in asphalt on Norwegian roads. This study followed a randomized, double-blind, cross-over study design. Using an exposure chamber, 24 healthy young volunteers were exposed to aggregates of two different types of rocks and placebo dust: quartz diorite, rhomb porphyry, and lactose (placebo dust). Each exposure session lasted for 4 hours (h), and blood samples were collected before exposure (baseline), 4 h post-exposure, and 24 h post-exposure to analyse potential changes in the von Willebrand factor (vWF) as well as of fibrinogen, d-dimer, leukocytes, and thrombocytes. The dust concentration in the exposure chamber was measured with real-time instruments and gravimetric samples of total dust, respirable dust, PM10, PM2.5, and ultrafine particles (UFP). The results were analysed using a linear mixed-effect model. Leukocyte blood counts increased post-exposure for all exposure materials; however, none of the increases were statistically significant. The concentration of fibrinogen increased after exposure to quartz diorite, while it decreased after exposures to rhomb porphyry and lactose. Type of material was a statistically significant explanatory variable for the concentration of fibrinogen, with the most significant increase occurring 24 h post-exposure to quartz diorite. After exposure to the three materials, vWF decreased. For the thrombocytes, an increase in blood count was observed 24 h post-exposure to quartz diorite and rhomb porphyry, with a modest (p = 0.09) positive association for quartz diorite. Although the results are limited, we conclude that the different effects observed post-exposure to quartz diorite support considering potential health effects when choosing materials in the production of asphalt.

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The Internet of Things (IoT) explores new perspectives and possible improvements in risk assessment practices and shows potential to measure long-term and real-time occupational exposure. This may be of value when monitoring gases with short-term maximum levels and for time-weighted average (TWA) concentrations used in standard measuring practices. A functional embedded system was designed using low-cost carbon monoxide (CO) electrochemical sensors and long-range-wide-area-network radio communication technology (LoRaWAN) was used to enable internet connectivity. This system was utilized to monitor gas levels continuously in the working atmosphere of an incineration plant over a 2-month period. The results show that stable and long-term continuous data transfer was enabled by LoRaWAN, which proved useful for detecting rapid changes in gas levels. However, it was observed that raw data from the low-cost sensors did not meet the NIOSH accuracy criteria of ± 25% of the estimated true concentration based on field data from a co-located gas detector that met the NIOSH accuracy criteria. The new IoT technologies and CO sensor networks shows potential for remote monitoring of exposure in order to: (1) detect rapid changes in CO and other possible hazardous airborne gases; and (2) show the dynamic range of real-time data that may be hazardous for workers in the sampled areas. While the IoT low-cost sensors appear to be useful as a sentinel for monitoring hazardous atmospheres containing CO, the more useful finding may be showing real-time changes and the dynamic range of exposures, thus shedding light on the transient and toxic nature of airborne hazards. More importantly, the low-cost CO sensors are not a clear substitute for the more costly real-time gas detectors that perform within the NIOSH accuracy criteria.

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We investigated how UV treatment of indoor pool water affects the concentration of trihalomethanes (THMs) and chloramines (NCl3) in the air above one therapy pool. One-hundred and sixty-two samples of tTHMs (sum of the four most common THMs in swimming facilities) and thirty-six samples of NCl3 were collected simultaneously at poolside and in the extract channel in a room with one therapy pool for 2 days a week over a period of 5 weeks. When the UV lamp was on, the concentration of combined chlorine in the water decreased 58%, the concentration of tTHMs in the air increased 37%, and the concentration of NCl3 in the air decreased 15%. Between 42% and 56% of the gases in the air are recirculated back into the poolroom along with the recycled air. The correlation between NCl3 and THMs in the air was stronger when the UV treatment was on (r2 = 0.963) compared to when the UV treatment was off (r2 = 0.472). Using a linear mixed model, 30% of the variability in THMs was attributed to UV treatment. For NCl3, the number of bathers was the most important predictor variable. UV treatment has a limited effect on airborne NCl3 but increases the air concentration of tTHMs.

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INTRODUCTION: Negative health effects related to long-term exposure to volatile trihalomethanes (THMs) formed during the chlorination of pool water is recognized, but the determinants causing the concentrations to vary within and between sampling locations have not received much attention. METHODS: One hundred and twenty air samples of four THMs were examined in three Norwegian indoor pool facilities. In each facility, repeated samples were collected above a sports pool and a therapy pool, 0.05 and 0.60 m above the water's surface. A linear mixed model (LMM) was used to identify determinants of exposure and the variability in THM concentration within and between sampling locations, days, and heights in pool facilities. RESULTS: The within variability of days, sampling locations, and heights was greater than between days, sampling locations, and heights. Determinants contributing significantly to the exposure were pool facility, height, swimming pool, day of the week, time during the day, and number of bathers. These findings limits how exposure categories should be defined to be able to identify the real long-term exposure and to propose suitable exposure limit values. DISCUSSION: These determinants could help future research be designed with effective sampling strategies and to collect information about the real long-term exposure, which is important in terms of establishing a dose-response relationship and exposure limit values. CONCLUSIONS: If unbiased exposure assessments are to be conducted among the different users of the pool facility, air samples should be collected over time and for different exposure scenarios.

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