Exposure characterization and risk assessment of ultrafine particles from the blast furnace process in a steelmaking plant.

OBJECTIVES: This study aimed to clarify the exposure characteristics and risks of ultrafine particles from the blast furnace process and to provide a reasonable control strategy for protecting the health of workers. METHODS: The blast furnace location of a steelmaking plant was selected as a typical investigation site. A membrane-based sampling system was used to collect ultrafine particles to analyze their morphology and elemental compositions. A real-time system was used to monitor the total number concentration (NC), total respirable mass concentration (MC), surface area concentration (SAC), and size distribution by number. The risk level of ultrafine particles was analyzed using the Stoffenmanager-Nano model. RESULTS: The total NC, total MC, and SAC increased significantly relative to background concentrations after slag releasing started and decreased gradually after the activity stopped. The three highest total concentrations during slag releasing were 3-10 times higher than those of the background or non-activity period. The ultrafine particles were mainly gathered at 10.4 or 40 nm, and presented as lump-like agglomerates. The metal elements (Al and Pt) in the ultrafine particles originated from slag and iron ore. The risk level of the ultrafine particles was high, indicating the existing control measures were insufficient. CONCLUSIONS: The blast furnace workers are at high risk due to exposure to high levels of ultrafine particles associated with working activity and with a bimodal size distribution. The existing control strategies, including engineering control, management control, and personal protection equipment need to be improved.

Emergency response to occupational brucellosis in a pharmaceutical manufacturing enterprise.

OBJECTIVES: Human brucellosis, as a zoonosis, is a serious public health problem in many developing countries, including China. To date, there has been no case report on occupational brucellosis and the emergency response in the pharmaceutical manufacturing industry. The aim of this report is to describe an emergency brucellosis outbreak in this unusual setting and the associated treatment methods from an occupational health perspective. METHODS: The emergency response included a field epidemiological investigation, a hierarchy of control strategy, and validation of control measures. RESULTS: Seven workers in the defrosting, grinding, and hydrolysis departments suffered from human brucellosis during two periods. The main symptoms were whole-body joint pain and undulant fever for several weeks, and Brucella-specific serum antibody was found in the patients. A hierarchy of exposure control strategy was implemented, including elimination, engineering control, administrative control, and the use of personal protection equipment. Raw material and environmental monitoring, measurement of placental temperature, Escherichia coli inactivation tests, and health examinations demonstrated that these measures were effective. CONCLUSIONS: This report describes an emergent case and the response to two consecutive outbreaks of occupational brucellosis among workers in a pharmaceutical manufacturing enterprise. The hierarchical control strategy used in this case may prevent new outbreaks, and several lessons can be learned from this event.