Associations between airborne crude oil chemicals and neurological symptoms among workers in the gulf long-term follow-up study.

Background: Many volatile organic compounds may be neurotoxic at occupational levels. However, little is known about the neurotoxicity of these chemicals below occupational exposure limits, including among oil spill response and cleanup (OSRC) workers.

Objective: We studied associations of neurological symptoms with exposure to benzene, toluene, ethylbenzene, xylenes, and n-hexane (BTEX-H) individually and as a mixture among 23,641 OSRC workers enrolled in the Gulf Long-Term Follow-up (GuLF) Study, a cohort following the 2010 Deepwater Horizon disaster.

Personal exposures to air pollutants and respiratory health among brick kiln workers and household members.

Background: Brick kiln workers (BKWs) may be exposed to high levels of respirable silica and other pollutants; however, few studies have measured personal exposures and health impacts in BKWs. We characterized exposures to brick kiln pollution and respiratory health among BKWs in Bhaktapur, Nepal.

Methods: We identified 64 brick kilns and selected a random sample of ten to conduct a household census and select a stratified random sample of 60 BKWs (makers, stackers, and haulers) aged ≥14 years with ≥10 years of kiln work, and household members aged ≥9 years.

Mesothelioma risks and cumulative exposure to elongate mineral particles of various sizes in Minnesota taconite mining industry.

Objectives: An excess of mesothelioma has been previously observed in iron ore miners in Northeastern Minnesota. This study explored the potential association between mesothelioma and elongate mineral particle (EMP) exposures in the Minnesota taconite mining industry, examining both regulated and non-regulated EMP dimensions.

Methods: A nested case-control study design within the Mineral Resources Health Assessment Programme cohort analysed 104 mesothelioma cases and 410 controls.

Estimating the time-varying emission rate of peracetic acid.

The use of peracetic acid (PAA) as a general disinfectant has seen increasing usage in recent years, and although it is a strong irritant, exposure monitoring for PAA may often be difficult due to relatively high costs and the potential for interferences by other co-occurring chemicals such as hydrogen peroxide. These issues with exposure monitoring make modeling a potentially useful tool in exposure assessment of PAA if model parameters can be accurately determined. This study estimates the time-varying mass emission rate of PAA for use in exposure modeling by using the small spill model and examines the effect of various environmental conditions on the PAA evaporation rate, including surface roughness/substrate, general ventilation rate, and local wind speed.

Volatile hydrocarbon exposures and immune-related illnesses among Deepwater Horizon oil spill workers.

Background: Despite evidence from experimental studies linking some petroleum hydrocarbons to markers of immune suppression, limited epidemiologic research exists on this topic.

Objective: The aim of this cross-sectional study was to examine associations of oil spill related chemicals (benzene, toluene, ethylbenzene, xylene, and n-hexane (BTEX-H)) and total hydrocarbons (THC) with immune-related illnesses as indicators of potential immune suppression.

Methods: Subjects comprised 8601 Deepwater Horizon (DWH) oil spill clean-up and response workers who participated in a home visit (1-3 years after the DWH spill) in the Gulf Long-term Follow-up (GuLF) Study.

Bayesian hierarchical modeling and inference for mechanistic systems in industrial hygiene.

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.

Application and demonstration of meso-activity exposure factors to advance estimates of incidental soil ingestion among agricultural workers.

Background: Soil is an understudied and underregulated pathway of chemical exposure, particularly for agricultural workers who cultivate food in soils. Little is known about how agricultural workers spend their time and how they may contact soil while growing food. Exposure factors are behavioral and environmental variables used in exposure estimation.

Subchronic exposure to ambient PM impairs novelty recognition and spatial memory.

Air pollution remains a great challenge for public health, with the detrimental effects of air pollution on cardiovascular, rhinosinusitis, and pulmonary health increasingly well understood. Recent epidemiological associations point to the adverse effects of air pollution on cognitive decline and neurodegenerative diseases. Mouse models of subchronic exposure to PM (ambient air particulate matter < 2.

Reliability of low mass toenail samples as biomarkers of chronic metal exposure.

Background: Toenails are a promising matrix for chronic metal exposure assessment, but there are currently no standard methods for collection and analysis. Questions remain about sample mass requirements and the extent to which metals measured in this matrix are representative of chronic body burden.

Objective: This study proposes a method to maximize sample conservation for toenail metals analysis using inductively coupled plasma mass spectrometry (ICP-MS).

Volatile Hydrocarbon Exposures and Incident Coronary Heart Disease Events: Up to Ten Years of Follow-up among Oil Spill Workers.

Background: During the 2010 () disaster, response and cleanup workers were potentially exposed to toxic volatile components of crude oil. However, to our knowledge, no study has examined exposure to individual oil spill-related chemicals in relation to cardiovascular outcomes among oil spill workers.

Objectives: Our aim was to investigate the association of several spill-related chemicals [benzene, toluene, ethylbenzene, xylene, -hexane (BTEX-H)] and total hydrocarbons (THC) with incident coronary heart disease (CHD) events among workers enrolled in a prospective cohort.

Exposure to volatile hydrocarbons and neurologic function among oil spill workers up to 6 years after the Deepwater Horizon disaster.

Background: During the 2010 Deepwater Horizon (DWH) disaster, oil spill response and cleanup (OSRC) workers were exposed to toxic volatile components of crude oil. Few studies have examined exposure to individual volatile hydrocarbon chemicals below occupational exposure limits in relation to neurologic function among OSRC workers.

Objectives: To investigate the association of several spill-related chemicals (benzene, toluene, ethylbenzene, xylene, n-hexane, i.

Efficacy of Grignard Pure to Inactivate Airborne Phage MS2, a Common SARS-CoV-2 Surrogate.

Grignard Pure (GP) is a unique and proprietary blend of triethylene glycol (TEG) and inert ingredients designed for continuous antimicrobial treatment of air. TEG has been designated as a ″Safer Chemical" by the US EPA. GP has already received approval from the US EPA under its Section 18 Public Health Emergency Exemption program for use in seven states.

Accuracy of professional judgments for dermal exposure assessment using deterministic models.

The accuracy of exposure judgments, particularly for scenarios where only qualitative information is available or a systematic approach is not used, has been evaluated and shown to have a relatively low level of accuracy. This is particularly true for dermal exposures, where less information is generally available compared to inhalation exposures. Relatively few quantitative validation efforts have been performed for scenarios where dermal exposures are of interest.

Experimental studies of particle removal and probability of COVID-19 infection in passenger railcars.

A series of experiments in stationary and moving passenger railcars was conducted to measure the removal rates of particles in the size ranges of SARS-CoV-2 viral aerosols, and the air changes per hour provided by the existing and modified air handling systems. The effect of ventilation and air filtration systems on removal rates and their effects on estimated probability (i.e.

A qualitative characterization of meso-activity factors to estimate soil exposure for agricultural workers.

Background: Agricultural workers' exposure to soil contaminants is not well characterized. Activity pattern data are a useful exposure assessment tool to estimate extent of soil contact, though existing data do not sufficiently capture the range and magnitude of soil contact in the agricultural context.

Objective: We introduce meso-activity, or specific tasks, to improve traditional activity pattern methodology.

Associations between airborne crude oil chemicals and symptom-based asthma.

Rationale: The 2010 Deepwater Horizon (DWH) oil spill response and cleanup (OSRC) workers were exposed to airborne total hydrocarbons (THC), benzene, toluene, ethylbenzene, o-, m-, and p-xylenes and n-hexane (BTEX-H) from crude oil and PM from burning/flaring oil and natural gas. Little is known about asthma risk among oil spill cleanup workers.

Objectives: We assessed the relationship between asthma and several oil spill-related exposures including job classes, THC, individual BTEX-H chemicals, the BTEX-H mixture, and PM using data from the Gulf Long-Term Follow-up (GuLF) Study, a prospective cohort of 24,937 cleanup workers and 7,671 nonworkers following the DWH disaster.

Potential Influence of Skin Hydration and Transepidermal Water Loss on the Dermal Transfer and Loading of Elemental Metallic Lead.

The factors influencing transfer of chemicals or other contaminants to and from the surface of the skin are often poorly understood. Previous research has indicated that environmental conditions, skin hydration, and repeated contacts may all influence the quantity of dermal transfer. The aim of this analysis was to evaluate the influence of skin hydration and condition on quantitative chemical transfer in a series of systematic measurements using human subjects for 5 and 10 repeated contacts.

Assessing Exposures from the Deepwater Horizon Oil Spill Response and Clean-up.

The GuLF Study is investigating adverse health effects from work on the response and clean-up after the Deepwater Horizon explosion and oil release. An essential and necessary component of that study was the exposure assessment. Bayesian statistical methods and over 135 000 measurements of total hydrocarbons (THC), benzene, ethylbenzene, toluene, xylene, and n-hexane (BTEX-H) were used to estimate inhalation exposures to these chemicals for >3400 exposure groups (EGs) formed from three exposure determinants: job/activity/task, location, and time period.

Estimation of Aerosol Concentrations of Oil Dispersants COREXIT™ EC9527A and EC9500A during the Deepwater Horizon Oil Spill Response and Clean-up Operations.

The April 2010 Deepwater Horizon drilling unit explosion at the Macondo oil well resulted in the release of approximately 779 million l of oil into the Gulf of Mexico. As part of the response effort to break up oil slicks on the water's surface, 6.81 million l of chemical dispersants COREXIT™ EC9500A and COREXIT™ EC9527A were applied by plane or vessel or injected near the seabed.

Exposure Group Development in Support of the NIEHS GuLF Study.

In the GuLF Study, a study investigating possible adverse health effects associated with work on the oil spill response and clean-up (OSRC) following the Deepwater Horizon disaster in the Gulf of Mexico, we used a job-exposure matrix (JEM) approach to estimate exposures. The JEM linked interview responses of study participants to measurement data through exposure groups (EGs). Here we describe a systematic process used to develop transparent and precise EGs that allowed characterization of exposure levels among the large number of OSRC activities performed across the Gulf of Mexico over time and space.

Assessing variability of aerosols generated from e-Cigarettes.

While some and experiments have studied the toxic effects of e-cigarette (e-cig) components, the typical aerosol properties released from e-cigarettes have not been well characterized. In the present study, we characterized the variability in mass concentration and particle size distribution associated with the aerosol generation of different devices and e-liquid compositions in an experimental setup. The findings of this study indicate a large inter-day variability in the experiments, likely due to poor quality control in some e-cig devices, pointing to the need for a better understanding of all the factors affecting exposures in and experiments, and the development of standardized protocols for generation and measurement of e-cig aerosols.