The China Benzene Sperm Study (C-BASS)

A Woman Walking Alone in an Air Separation Factory in China

The China Benzene Sperm Study (C-BASS) examines whether occupational benzene exposure may be related to genetic damage to sperm. 

Benzene is a common environmental pollutant present in crude oil, smoke, gasoline, paints, adhesives and solvents. It is listed among the International Agency for Research on Cancer (IARC) Group 1 human carcinogens, found to induce leukemia & lymphoma and is associated with increased chromosomal anomalies in cells.

The United States Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) is 1 part of benzene per million parts (ppm) averaged over 8 hours. The China Occupational Exposure Limit (OEL) permits almost twice this level, at 1.9 ppm. 

Factory Worker in China

Study at a Glance: 

  • Study Objectives:  Investigate in detail the specific relationship between benzene exposure and genetic damage to sperm 
  • Geographic Area: Tianjin, China.
  • Participants: 96 men, 18 to 50 years old
  • Study Tools: Interview, sperm sample and blood sample. Personal passive-air badge sample and urine sample collected at two time point per participant.
  • Principal Investigators: Dr. Brenda Eskenazi
  • Funders: National Institute for Environmental  Health Sciences (NIEHS) and U.S. Environmental Protection Agency (EPA) Superfund Research Program