Mean barium concentrations in background air collected from April-October 2002 at the University of Birmingham, United Kingdom, were 0.32 and 1.4 ng/cu m, respectively(1).
Literature: (1) ATSDR; Toxicological Profile for Barium and Barium Compounds. Atlanta, GA: Agency for Toxic Substances and Disease Registry, US Public Health Service (2007)
http://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+6934

ATSDR = Agency for Toxic Substances and Disease Registry
http://www.atsdr.cdc.gov/

Last edited by Denglisch; 01/25/14 06:17 PM.