A series of experiments in stationary and moving passenger rail cars were conducted to measure removal rates of particles in the size ranges of SARS-CoV-2 viral aerosols and the air changes per hour provided by existing and modified air handling systems. Such methods for exposure assessments are customarily based on mechanistic models derived from physical laws of particle movement that are deterministic and do not account for measurement errors inherent in data collection. The resulting analysis compromises on reliably learning about mechanistic factors such as ventilation rates, aerosol generation rates, and filtration efficiencies from field measurements. This manuscript develops a Bayesian state-space modeling framework that synthesizes information from the mechanistic system as well as the field data. We derive a stochastic model from finite difference approximations of differential equations explaining particle concentrations. Our inferential framework trains the mechanistic system using the field measurements from the chamber experiments and delivers reliable estimates of the underlying physical process with fully model-based uncertainty quantification. Our application falls within the realm of the Bayesian \"melding\" of mechanistic and statistical models and is of significant relevance to environmental hygienists and public health researchers working on assessing the performance of aerosol removal rates for rail car fleets.

Occupational noise exposure continues to be a prevalent hazard in many industries. While the proliferation of noise dosimeters and wearable devices has made it easier to assess a worker\'s exposure to noise, many employees exposed to hazardous (i.e., >85 dBA) levels of noise may go their entire career without ever having their personal noise levels measured. In contrast to other occupational exposures, noise is easily perceived by the individual exposed, allowing them to develop subjective judgments regarding its characteristics. To determine whether such self-reported exposures to occupational noise are associated with hearing loss, this analysis used audiometric data and self-reported occupational exposure to loud noise from the National Health and Nutrition Examination Survey (NHANES), which has collected such data from 1999 to May 2020. Linear and logistic regressions models found a statistically significant association between self-reported noise exposure and worsened hearing at the 3, 4, 6, and 8 kHz hearing frequency as well as an elevated odds ratio for the development of hearing loss greater than 25 dB at the 2, 3, and 4 kHz audiometric frequencies. The results of this analysis suggest that in the absence of exposure measurements, workers are likely able to detect exposure to hazardous levels of noise. In these instances, additional measurements should be collected to determine if the workers should be enrolled in a hearing conservation program.

Both nitric oxide (NO) and nitrogen dioxide (NO2) gasses are toxic to humans but are commonly found in industrial settings such as semiconductor manufacturing sites. Due to the spontaneous oxidation of NO to NO2 under ambient conditions, individuals working with NO may in fact be exposed to both gasses in the case of an accidental release. Unfortunately, most safety materials provided to NO users do not address the potential for associated NO2 toxicity, and, until now, models developed to predict health consequences following a release of NO have not appropriately considered the oxidation kinetics nor the toxicity of both NO and NO2 in their assessments. This paper describes an improved multi-module model that addresses these limitations and explores whether facilities using NO should consider adopting measures that can mitigate the simultaneous health effects of both gasses. The model predicts the morbidity (intoxication/injury), mortality (death), and treatment outcomes that may arise following an industrial NO release by first calculating the doses of both NO and NO2 received by exposed individuals and then applying newly defined toxicity parameters for NO and NO2 to assign dose-dependent probabilities for the onset of intoxication and/or death and the ability of appropriate treatment(s) to save lives. Modeling results indicate low risk to worker health in the likeliest release scenarios while identifying less likely situations that carry substantially higher risk. Moreover, these results indicate that risks to worker health can be mitigated with simple measures like maintaining reliable alarms, adequate ventilation, and on-site supplies of methylene blue, as well as encouraging quick responses by personnel. With appropriate parameterization, the improved modeling framework is generalizable to any chemical release, especially multi-hazard releases resulting from the conversion of one toxic compound into another under likely environmental conditions. By directly addressing the toxicities of multiple compounds, the improved model presents a more realistic picture of the potential health consequences of a chemical release. This generalizable framework for modeling of multi-hazard chemical releases can inform preparedness and risk mitigation strategies for NO release events.

We investigated the level of protection of reproductive and developmental toxicity offered through occupational exposure limits (OELs) and Derived No-Effect Levels for workers\' inhalation exposure (wDNELs). We compared coverage of substances that have a harmonised classification as reproductive toxicant 1 A or 1B (Repr.1 A/B), numerical values and scientific basis of 12 lists of OELs and wDNELs from REACH Registrants\' and the Committee for Risk Assessment. Across the 14 sources of OELs and wDNELs, 53 % of the Repr1A/B-substances had at least one exposure limit (counting groups of metals as one entry). Registrants\' wDNELs covered the largest share, 40 %. The numerical values could be highly variable for the same substance across the lists. How often reproductive toxicity is identified as the critical effect varies between the examined lists, both due to different assessments of the same substance and different substance coverage. Reviewing the margin of safety to reproductive toxicity cited in the documents, we found that 15 % of safety margins were lower to reproductive toxicity than the critical effect. To conclude, neither the REACH nor work environment legislation supply wDNELs or OELs for a substantial share of known reproductive toxicants. EU OELs cover among the fewest substances in the range, and in many cases national OELs or wDNELs are set at more conservative levels.

The aim of the study was to assess non-occupational and occupational exposure to bisphenol compounds in Finland. The participants were 151 non-occupationally exposed volunteers and 15 potentially exposed employees of a sewage-pipe relining company and a floor-coating company. The following chemicals were measured in the urine samples: bisphenol A (BPA), bisphenol F (BPF), bisphenol A diglycidyl ether (BADGE), bisphenol F diglycidyl ether (BFDGE), and the metabolites of the latter two [bisphenol A (2,3-dihydroxypropyl) glycidyl ether (BADGE·H2O), bisphenol A bis(2,3-dihydroxypropyl) ether (BADGE·2 H2O), bisphenol A (3-chloro-2-hydroxypropyl) (2,3-dihydroxypropyl) ether (BADGE·HCl·H2O), bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether (BADGE·HCl), and bisphenol A bis(3-chloro-2-hydroxypropyl) ether (BADGE·2HCl) and bisphenol F bis(2,3-dihydroxypropyl) ether (BFDGE·2 H2O), and bisphenol F bis(3-chloro-2-hydroxypropyl) ether (BFDGE·2HCl)]. BADGE and BFDGE were also measured in breathing zone air samples and hand-wipe samples of the sewage-pipe relining and floor-coating workers. Non-occupational exposure to BPA has decreased in Finland. The BPF level of the non-occupationally exposed was higher than the respective levels reported in the recent literature. BPA and BPF concentrations in the workers\' urine samples were in the same range as those in the corresponding concentrations of the non-occupationally exposed population. Higher concentrations of BADGE and BFDGE metabolites were found in some of the workers\' urine samples. Elevated urine concentrations were also observed in the samples collected the next morning. Some of the urinary BADGE and BFDGE metabolite results correlated with the hand-wipe results. The results show that occupational exposure to BADGE and BFDGE may occur in sewage-pipe relining and floor-coating work. They also indicate that dermal contamination plays a role in total exposure. Although the measured urinary levels indicate that the absorption of these bisphenol compounds are unlikely to pose a systemic health risk, the risk of dermal sensitization remains.

A vast variety of chemical compounds have been fabricated and commercialized, they not only result in industrial exposure during manufacturing and usage, but also have environmental impacts throughout their whole life cycle. Consequently, attempts to assess the risk of chemicals in terms of toxicology have never ceased. In-silico toxicology, also known as predictive toxicology, has advanced significantly over the last decade as a result of the drawbacks of experimental investigations. In this study, ProTox-III was applied to predict the toxicity of the ligands used for metal-organic framework (MOF) design and synthesis. Initially, 35 ligands, that have been frequently utilized for MOF synthesis and fabrication, were selected. Subsequently, canonical simplified molecular-input line-entry system (SMILES) of ligands were extracted from the PUBCHEM database and inserted into the ProTox-III online server. Ultimately, webserver outputs including LD50 and the probability of toxicological endpoints (cytotoxicity, carcinogenicity, mutagenicity, immunotoxicity, and ecotoxicity) were obtained and organized. According to retrieved LD50 data, the safest ligand was 5-hydroxyisophthalic. In contrast, the most hazardous ligand was 5-chlorobenzimidazole, with an LD50 of 8 mg/kg. Among evaluated endpoints, ecotoxicity was the most active and was detected in several imidazolate ligands. This data can open new horizons in design and development of green MOFs.

The American Iron and Steel Institute (AISI) gathered data between 1989 and 1997 to build an \"objective database\" to further understand the occupational exposures generated by the few asbestos-containing materials remaining at various steelmaking companies at this time. This paper analyzed the 520 samples from this campaign which occurred at five different steel manufacturers: Georgetown Steel Company, Inland Steel Company, Ling-Temco-Vought (LTV) Corporation, United States Steel Corporation, and Weirton Steel Corporation. This database is believed to have never previously been systematically organized. Samples were grouped based on sampling times to determine whether they should most appropriately be compared to the OSHA short-term excursion limit (EL) or the 8-hr time-weighted average (TWA) permissible exposure limit (PEL). Sampling times of 30 min or less were considered short-term samples, and samples of 180 min or greater were considered representative workday samples. Samples that did not fit into either category, with sampling times between 31 and 179 min, were considered task samples. Overall, the data indicated that the airborne concentrations were quite low in 1989 and they continued to be low through the study period which ended in 1997. Only seven out of 286 (approximately 2.5%) short-term or representative workday samples were in exceedance of the current OSHA OELs that were implemented in 1994 (short-term samples being compared to the 1 f/cc EL and representative workday samples being compared to the 0.1 f/cc 8-hr TWA PEL). Consistent with prior data, analysis of this dataset supports the view that materials containing asbestos were not used in many applications in the steel industry, and measured airborne concentrations of asbestos were almost always below the occupational exposure limits (OELs) in the post-OSHA era (1972-2000).

Graduates of industrial hygiene training (IH) programs must be able to meet continuously evolving health and safety needs in a wide variety of occupational settings. Therefore, academic IH graduate programs must regularly evaluate their curricula and solicit input from industry professionals to make curricular changes that will better prepare their students for professional roles in industry. The purpose of this study was to identify the training gaps that existed between industry needs and the current curriculum for a United States-accredited IH graduate training program. The research team facilitated two group interviews with the IH program advisory board, collected alumni survey data, and performed a qualitative analysis to identify skills gaps/needs for the IH Program graduates. The research team identified 3 themes from participant interviews and alumni surveys (technical, applied, and essential skills) and selected several skills within each theme that interview participants thought were necessary proficiencies for junior IH professionals. The skills identified in the qualitative interview and survey data can be incorporated into the curriculum to improve the training of IH graduate students. Additionally, by using qualitative analysis, the researchers uncovered essential skills previously unidentified in IH needs assessments, providing valuable information for all IH graduate programs.

This study describes a method whose aim is to help companies assess the chemical occupational risks related to labeled products and industrial chemical emissions. The method is intended to be used by industrial hygienists at the scale of one company. Both inhalation and cutaneous exposure routes are taken into account.
The method relies on a control-banding scheme. A work situation is described by exposure parameters such as the process or the local exhaust ventilation and by the hazard of the product. Each possible value of the parameters is associated with a \"band,\" which is associated with an integer value. The multiplication of these values results in a score, which represents a priority for intervention. The higher the score, the more the situation warrants investigation for implementing prevention measures, such as chemical substitution and the addition of local exhaust ventilation. To simplify communication, the priority is associated with a colored priority band: red for \"very high priority,\" orange for \"high priority,\" and green for \"moderate priority.\" The priority bands are computed for all work situations performed in a company.
An example of the use of this method is described in a French façade insulation company.
A tool named Seirich was developed to implement this method and promote good practices for helping industrial hygienists in the prioritization of interventions for reducing chemical risk in France.

The NIOSH Pocket Guide to Chemical Hazards is a trusted resource that displays key information for a collection of chemicals commonly encountered in the workplace. Entries contain chemical structures-occupational exposure limit information ranging from limits based on full-shift time-weighted averages to acute limits such as short-term exposure limits and immediately dangerous to life or health values, as well as a variety of other data such as chemical-physical properties and symptoms of exposure. The NIOSH Pocket Guide (NPG) is available as a printed, hardcopy book, a PDF version, an electronic database, and a downloadable application for mobile phones. All formats of the NIOSH Pocket Guide allow users to access the data for each chemical separately, however, the guide does not support data analytics or visualization across chemicals. This project reformatted existing data in the NPG to make it searchable and compatible with exploration and analysis using a web application. The resulting application allows users to investigate the relationships between occupational exposure limits, the range and distribution of occupational exposure limits, and the specialized sorting of chemicals by health endpoint or to summarize information of particular interest. These tasks would have previously required manual extraction of the data and analysis. The usability of this application was evaluated among industrial hygienists and researchers and while the existing application seems most relevant to researchers, the open-source code and data are amenable to modification by users to increase customization.