Sharifah Mazrah Sayed Mohamed Zain1*, Rafiza Shaharudin1
1. Environmental Health Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, 1 Jalan Setia Murni U13/52, Section U13, Setia Alam, 40170 Shah Alam, Selangor, Malaysia
*Corresponding author:
CITATION: Sayed Mohamed Zain SM, Shaharudin R. Real-time elemental mercury vapor levels in an indoor test environment. International Medical Research Journal. 2024 Oct;10(1):72–83.
ABSTRACT
This study measured elemental mercury (Hg0) vapour concentrations released from a known amount of Hg0, simulating various thermometer and sphygmomanometer spillage scenarios in an indoor test environment. A volume of 0.15 mL and 5 mL Hg0 spills were tested at 25±1ᵒC and 30±1ᵒC room temperature, measured at different heights and distances from the spills. Hg0 vapour concentrations were measured in real-time using a Mercury Survey Meter EMP-2 with an interval of 30 min for two hours. The average concentration of Hg0 vapor emitted from the 0.15 mL spill was between 0.1±0.3 µg m−3 and 6.6±11.0 µg m−3, whereas the 5 mL Hg0 spill showed a higher range from 1.0±0.3 µg m−3 to 24.8 ± 8.5 µg m−3. The difference in Hg0 concentration between a large spill and a small spill at 25ᵒC and 30ᵒC were 11.4 and 8.6 times higher, respectively. The average test room concentrations ranged from 0.4 µg m−3 to 16.8 µg m−3, exceeding the Agency for Toxic Substances and Disease Registry chronic minimal risk level of 0.3 µg m−3. The Mann-Whitney U test revealed a significant difference in the median Hg0 concentration between the spill amount (p<0.032) and room temperature (p<0.005). This study successfully provides an estimate of mercury spill levels caused by the breakage of a thermometer or sphygmomanometer implying that a small or large spill in a warm room with low ventilation could result in significantly higher levels of Hg0 vapour, posing a risk to human health.
KEYWORDS: Thermometer, Sphygmomanometer, Spill, Indoor Air, Tropical Climate
