NIOSH Evaluates Mercury and Noise Hazards at Lightbulb Recycling Facility
In September, NIOSH released a health hazard evaluation (HHE) report providing a set of recommended controls for mercury and noise hazards at a lightbulb recycling facility. At the request of management, NIOSH visited the facility to measure employees’ mercury and noise exposures and observe how the crew of 15 sorted and crushed lightbulbs manually and through the use of machines. Phosphor dusts from broken lightbulbs may contain mercury, which may be emitted into the air, the HHE report explains.
Of the 18 personal air samples collected by NIOSH evaluators, 10 indicated mercury levels above ACGIH’s Threshold Limit Value, and seven showed mercury levels above NIOSH’s recommended exposure limit (REL) for a normal workday, but none exceeded OSHA’s permissible exposure limit for mercury. Five out of 14 employees who provided urine samples had elevated mercury levels (an additional sample was too dilute to interpret, NIOSH noted) above the limit set by professional guidelines, and 10 of the 15 employees reported health symptoms they thought were work related. These symptoms included a metallic or bitter taste in their mouths, changes in personality, and difficulties with thinking and writing, which are consistent with mercury exposure. For noise exposures, 10 out of 18 full-shift personal noise exposure measurements taken by NIOSH indicated noise levels above the agency’s REL, and seven showed noise exposures above OSHA’s action level.
The HHE report’s first recommendation is that the employer reduce exposures to mercury-containing dust. Inhalation of mercury can harm the lungs in the short term and cause tremors, memory loss, mood changes, and mouth ulcers in the long term. At this facility, management could control mercury exposures by installing local exhaust ventilation in production areas and improving air flow in nonproduction areas. Better housekeeping procedures, such as using a vacuum designed for mercury cleanup rather than sweeping up broken bulbs and dust, may also help reduce mercury exposures. The employer could also implement administrative controls such as separating “clean” and “dirty” functions in the facility, removing dust from clothing and surfaces, and standardizing the personal protective equipment for workers exposed to dust.
To control noise exposures, the HHE report recommends that the employer implement a hearing conservation program; ensure regular maintenance, isolation, or enclosure of equipment; and require workers to use hearing protection in noisy areas. NIOSH also recommends that management periodically reevaluate and perform maintenance on safety controls, conduct comprehensive air monitoring throughout the facility, and encourage employees to report new, persistent, or worsening symptoms to healthcare providers. Finally, the report addresses a handful of safety concerns unrelated to mercury or noise exposure, such as the safe use of forklifts and pallets.
The HHE report may be downloaded as a PDF from NIOSH’s HHE report library.