Harbin Institute of Technology and other institutions published a study in the Journal of Hazardous Materials, screening cerebrospinal fluid samples from 91 subjects in Harbin who self-reported no history of occupational pesticide exposure, and detected a total of 20 pesticide-related compounds; biphenyl was detected in all samples, and 6 triazole components were also found. On October 18, a blogger posted a video introducing the study.