Assessing and Reducing Taxi Drivers’ Exposure to Ultrafine Particles

Details

• Personal Author:
  Ritz B ; Shu S ; Weiss R ; Yu N ; Zhu Y
• Description:
  Taxi drivers are expected to have high occupational exposure to traffic-emitted air pollutants because they spend long working-hours on freeways and local streets where concentrations of air pollutants such as ultrafine particles (UFPs) are high. In this study, we focused on two specific aims: (1) to identify the major factors that impact the taxi drivers' occupational exposure to UFPs and (2) to develop a cost-effective strategy to mitigate taxi drivers' occupational exposure to UFPs. We recruited 22 taxi drivers in the Greater Los Angeles area in California in this study. We worked with each of them to collect air pollutant data, environmental factors (i.e. temperature, humidity, and noise level), and health indicators (i.e. ambulant blood pressure and heart rate). For each driver and his/her taxi cab, tests were conducted on four consecutive days. On each test day, the driver drove 6 hours in the Greater Los Angeles area as he or she would typically do. One field technician rode along in the taxi cab operating and maintaining all the sampling instruments. For the first two days, the original equipped manufacturer (OEM) cabin air filter was used in the taxi cab, to represent the drivers' actual working conditions. For the last two days, a custom-made High Efficiency Cabin Air (HECA) filter was used to replace the OEM cabin air filter, to test the effectiveness of HECA filter in reducing taxi drivers' occupational exposure to UFPs. In additional to the two proposed specific aims, we also (1) calculated the air exchange rates (AERs) in taxi cabin by using CO2 as tracer gas, (2) collected and analyzed taxi drivers' urine samples twice a day to explore the biomarkers of UFP exposures, and (3) explored how the exposure to air pollutants impact taxi drivers' ambulatory blood pressure. On average, taxi drivers in the Greater Los Angeles area work 11.9 +/- 2.3 hours a day, and 6.1 +/- 0.8 days a week. The on-road data collected from this study, showed UFP concentration ranges from 105 to 5x105 particles/cm3. Data showed that the on-road UFP concentrations were affected by the road type (freeways or local streets), however, driving speeds didn't affect the UFP levels significantly. The AERs were generally higher in taxi cabs compared with private passenger vehicles. The UFP in-cabin to on-roadway (I/O) ratios in taxi cabs were not significantly different between freeways and local streets, but affected by the interventions (window positions and HECA filter availabilities) significantly. Using HECA filter can significantly reduce both the UFP concentrations and UFP I/O ratios in taxi cabs. The reduction was more obvious when the drivers kept the windows closed. Results from the urinary biomarker analysis showed 1- and 2-NAP, 1-PYR and 9-FLU levels in the taxi driver group were significantly higher than the general population. [Description provided by NIOSH]
• Subjects:
  Air Pollutants, Occupational Air Pollution Automobiles Biomarkers Occupational Health Particulate Matter Safety Transportation
• Keywords:
  Air Analysis Airborne Particulates Air Filters Air Pollutants Air Quality Monitoring Biological Effects Drivers Motor Vehicles Physiological Effects Transportation Industry Ultrafine Particles

  More +
• Series:
  Grant Final Reports
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Final Grant Report
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  OEP - Office of Extramural Programs
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-47
• NIOSHTIC Number:
  nn:20053184
• NTIS Accession Number:
  PB2019-100190
• Citation:
  Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, R21-OH-010196, 2015 Sep; :1-47
• Contact Point Address:
  Yifang Zhu, UCLA Fielding School of Public Health, Department of Environmental Health Sciences, 650 Charles Young Drive South
• Email:
  yifang@ucla.edu
• Federal Fiscal Year:
  2015
• NORA Priority Area:
  Transportation, Warehousing and Utilities
• Performing Organization:
  University of California, Los Angeles
• Peer Reviewed:
  False
• Start Date:
  20120731
• Source Full Name:
  National Institute for Occupational Safety and Health
• End Date:
  20150630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:46ecbf7215b25aaa2eeee3d6e560c1fad848ac7c7097a26d60bf4b0148a7f66f338c95f5090b89b920a75aac159d618e8924ca4e4ab97bad52a4a72952a426cd
• Download URL:
  https://stacks.cdc.gov/view/cdc/218753/cdc_218753_DS1.pdf
• File Type:
  [PDF - 2.09 MB ]