Comprehensive Assessment of Occupationally Relevant Exposures
NIEHS is coordinating an NTP effort with NIOSH to better understand worker exposures, identify occupational health research gaps, and educate workers. The NIEHS and NIOSH interagency agreement supports these projects. The FY 2017 efforts listed below address worker exposures to welding fumes, nanosized materials, food flavorings, and other industrial chemicals. Click the project title for a brief summary.
NIOSH mobile lab for field studies
Study Scientist: Elizabeth Whelan
Support of NIOSH scientists in (1) participating in review and oversight of NTP activities and (2) attending NTP-related meetings in Research Triangle Park, North Carolina and Washington, D.C.
Study Scientist: Kevin Hanley
Characterization of welding fume exposures with a focus on manganese. Welders’ exposures to total and respirable manganese were evaluated using a novel sequential chemical extraction method to (1) identify industries, such as construction, shipbuilding, manufacturing companies, and unions, involved in welding operations for which the potential for substantial manganese exposure exists; (2) develop methods to identify manganese compounds and different oxidation states based on selective solubility with various welding fume matrices; and (3) characterize welding fume exposures based on welding-associated jobs, tasks, and processes. Three hundred full-shift worker-days were assessed during stick electrode welding, gas metal arc welding, flux cored welding, and gas tungsten arc welding in construction, refineries, heavy equipment, structural steel, shipyard, and appliance industries. To date, three manuscripts have been published (and a fourth has been submitted to a journal) that demonstrated excessive manganese exposures associated with welding fumes, often exceeding Threshold Limit Values of the American Conference of Governmental Industrial Hygienists (ACGIH TLVs) by an order of magnitude.
Study Scientist: Charles Geraci
Identification of workplaces engaged in the synthesis, manufacture, and use of engineered nanomaterials and characterization of workplace exposures to selected engineered nanoparticles.
Study Scientist: Aleksandr Stefaniak
Investigation of the in vitro durability of nanocellulose materials in artificial lung fluids. Data generated from this study will be used to inform larger in vivo inhalation studies.
Study Scientist: Cheryl Estill
Assessment of exposure to nine alternative flame retardants plus a panel of polybrominated diphenyl ethers. Exposure has been assessed at 19 facilities involved in the manufacture, installation, or use of goods containing these flame retardants. Worksite categories included are manufacture of products that use flexible polyurethane foams; fabrication and manufacture of rigid polystyrene foam; cutting, installing, or spraying polyurethane foam insulation at construction sites; gymnasiums; nail salons; and the fire service industry. This study is comparing exposures among industries, processes, and tasks; determining the routes of exposure; and making recommendations to reduce exposures. These data will be used to determine exposure levels of workers in different occupations and how they relate to the general population by comparison to the National Health and Nutrition Examination Survey data. The results will aid in the design, understanding, and use of toxicological studies and risk assessment.
Study Scientist: Kevin Hanley
Evaluation of the levels of occupational chemical exposure among workers who are using coal tar-based pavement sealants. Coal tar is sometimes used as a base material for blacktop pavement sealants, accounting for as much as 35% of the formulation in some of these products. Coal tar is a byproduct of the production of coke, which is needed for steel production. Coal tar pitch volatiles are a mixture of chemicals that can evaporate into air from products containing coal tar, including coal tar pavement sealants. Coal tar sealant aerosols and volatiles contain several chemicals known as PAHs. This study focuses on the assessment of occupational exposure to PAHs among coal tar sealant workers. Currently, no data are available in the scientific literature on exposure to PAHs and their metabolites for workers applying coal tar sealant-based coatings on pavements. This study is providing data regarding levels of exposure to airborne chemicals for comparison to current NIOSH recommended exposure limits, if available. Results for specific PAH chemicals using NIOSH analytical methods will be reported. PAHs are measured in dermal wipe samples, and PAH metabolites measured in biological samples collected from workers to characterize levels present in this workforce. In FY 2017, construction surveys increased the database by 968 PAH measurements for air exposure time-weighted-average calculations, 968 skin wipe PAH measurements; and 704 PAH metabolite analyses in urine specimens.