An outbreak of work-related asthma and silicosis at a US countertop manufacturing and fabrication facility.

Background: Outbreaks of severe silicosis have affected workers who fabricate artificial stone countertops. Work-related asthma (WRA) has not been a prominent feature of those prior outbreaks.

Methods: This report describes an outbreak of WRA and silicosis at a facility that manufactures and fabricates chemical-resistant countertops comprised of sand, epoxy resin, and phthalic anhydride (PA), a known respiratory sensitizer.

Methemoglobinemia resulting from exposure in a confined space: Exothermic self-polymerization of 4,4'-methylene diphenyl diisocyanate (MDI) material.

A worker attempting to remove solidified material inside a confined space (storage tank) suffered severe methemoglobinemia and almost died. The tank contained liquid 4,4'-methylene diphenyl diisocyanate monomer that had solidified after an equipment power failure caused excessive heating. Wearing a full-face elastomeric air-purifying respirator and Tyvek® coveralls, the worker used pneumatic air hammers to break up the solid material.

The influence of bone-density on in vivo K x-ray fluorescence bone-lead measurements.

Mathematical simulations and benchmark measurements were performed to assess the impact that normal variations in human calcium content have on in vivo K x-ray fluorescence measurements of lead in bone. Four sets of cortical bone tissue simulants were fabricated containing from 20.8% to 23.

A cohort mortality study of chemical laboratory workers at Department of Energy Nuclear Plants.

Objective: This study evaluates the mortality experience of 6,157 chemical laboratory workers employed at United States Department of Energy facilities.

Methods: All cause, all cancer and cause-specific standardized mortality ratios were calculated. Cox regression analyses were conducted to further evaluate the relation between chemical exposure and mortality risk due to selected cancers.

Estimation of radon exposures to workers at the Fernald Feed Materials Production Center 1952-1988.

The Feed Materials Production Center (FMPC) at Fernald, Ohio produced uranium metal products for use in Department of Energy defense programs. Radium-contaminated waste material was stored on-site in two K-65 silos on the west side of the facility and provided a source of 222Ra. The initial objective of this study was to estimate radon exposures to employees at FMPC working from 1952 to 1988.