RT Journal Article SR Electronic T1 Biological effects of low level exposures dose response relationships JF Occupational and Environmental Medicine JO Occup Environ Med FD BMJ Publishing Group Ltd SP 791 OP 792 DO 10.1136/oem.53.11.791-c VO 53 IS 11 A1 Dayan, A D YR 1996 UL http://oem.bmj.com/content/53/11/791.4.abstract AB