title: Effects of continuous and pulsed 2450-MHz radiation on spontaneous lymphoblastoid transformation of human lymphocytes in vitro.
abstract: Normal human lymphocytes were isolated from the peripheral blood of healthy donors. One-ml samples containing (10(6)) cells in chromosome medium 1A were exposed for 5 days to conventional heating or to continuous wave (CW) or pulsed wave (PW) 2450-MHz radiation at non-heating (37 degrees C) and various heating levels (temperature increases of 0.5, 1.0, 1.5, and 2 degrees C). The pulsed exposures involved 1-microsecond pulses at pulse repetition frequencies from 100 to 1,000 pulses per second at the same average SAR levels as the CW exposures. Actual average SARs ranged to 12.3 W/kg. Following termination of the incubation period, spontaneous lymphoblastoid transformation was determined with an image analysis system. The results were compared among each of the experimental conditions and with sham-exposed cultures. At non-heating levels, CW exposure did not affect transformation. At heating levels both conventional and CW heating enhanced transformation to the same extent and correlate with the increases in incubation temperature. PW exposure enhanced transformation at non-heating levels. This finding is significant (P less than .002). At heating levels PW exposure enhanced transformation to a greater extent than did conventional or CW heating. This finding is significant at the .02 level. We conclude that PW 2450-MHz radiation acts differently on the process of lymphoblastoid transformation in vitro compared with CW 2450-MHz radiation at the same average SARs.
authors.affiliation: Center for Devices and Radiological Health, Food and Drug Administration, Rockville, Maryland.
authors.forename: E M
authors.initials: EM
authors.lastname: Czerska
authors.forename: E C
authors.initials: EC
authors.lastname: Elson
authors.forename: C C
authors.initials: CC
authors.lastname: Davis
authors.forename: M L
authors.initials: ML
authors.lastname: Swicord
authors.forename: P
authors.initials: P
authors.lastname: Czerski
mesh_terms: D006358:Hot Temperature; D006801:Humans; D066298:In Vitro Techniques; D008213:Lymphocyte Activation / Q000528:radiation effects*; D008872:Microwaves