Medical/biological study (experimental study)

Induction of adaptive response in human blood lymphocytes exposed to 900 MHz radiofrequency fields: Influence of cell cycle med./bio.

By: Sannino A, Zeni O, Sarti M, Romeo S, Reddy SB, Belisario MA, Prihoda TJ, Vijayalaxmi, Scarfi MR

Published in: Int J Radiat Biol 2011; 87 (9): 993-999

Aim of study (acc. to author)

To study the influence of the cell cycle on the adaptive response induced by the exposure of human blood lymphocytes to radiofrequency fields.

Background/further details

Adaptive response: Different cell types that were exposed to an extremely small adaptation dose of a genotoxic agent were found to be less susceptible to the induction of genetic damage when given a higher challenge dose of the same or similar genotoxic agent. The induction of an adaptive response was shown to be influenced by several factors (e.g. the dose used for adaptation, the dose rate, the time between the adaptation and challenge doses).
Human peripheral blood lymphocytes in G₀ phase, G₁ phase or S phase of the cell cycle were exposed for 20 hours to an adaptive dose of 900 MHz radiofrequency and then treated with a challenge dose of 100 ng/ml mitomycin C.
Lymphocytes of nine different healthy male donors were investigated.

Endpoint

genotoxicity/mutation: DNA damage (micronucleus formation)

Exposure

- RF
- mobile communications
- mobile phone
- GSM

Exposure	Parameters
Exposure 1: 900 MHz Exposure duration: continuous for 20 h	SAR: 1.25 W/kg average over time SAR: 10 W/kg peak value

Exposure 1

Main characteristics

Frequency	900 MHz
Type	electromagnetic field
Exposure duration	continuous for 20 h

Exposure setup

Exposure source	wire patch cell
Setup	two wire patch cells placed inside an incubator with a constant temperature of 36.9° C +/- 0.5° C and a humidified atmosphere of 5% carbon dioxide and 95% air
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
SAR	1.25 W/kg	average over time	-	-	-
SAR	10 W/kg	peak value	-	-	-

Reference articles

Sannino A et al. (2009): Induction of adaptive response in human blood lymphocytes exposed to radiofrequency radiation
Palumbo R et al. (2008): Exposure to 900 MHz radiofrequency radiation induces caspase 3 activation in proliferating human lymphocytes
Scarfi MR et al. (2006): Exposure to radiofrequency radiation (900 MHz, GSM signal) does not affect micronucleus frequency and cell proliferation in human peripheral blood lymphocytes: an interlaboratory study

Exposed system:

intact cell/cell culture

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: micronucleus formation (cytokinesis block micronucleus assay; Giemsa stain; light microscopy)
cell viability/cell division/proliferation: cytotoxicity (proliferation index (M1+2M2+3(M3+M4)/total number of cells; M1 to M4: number of cells with 1 to 4 nuclei); binucleate cell index (percentage of binucleated cells))

Investigated system:

intact cell/cell culture
chromosomes

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The data indicated that the cells which were exposed to an adaptive dose of radiofrequency in G₀ phase and G₁ phase of the cell cycle did not exhibit an adaptive response while such a response was observed when the cells were exposed to an adaptive dose of radiofrequency in the S phase of the cell cycle.
These findings confirmed the observations reported in previous investigations (Sannino et al. 2009) where an adaptive response was found in human blood lymphocytes exposed to an adaptive dose of radiofrequency in S phase of the cell cycle and further suggested that the timing of an adaptive dose exposure of radiofrequency is important to elicit an adaptive response.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

not stated/no funding

Zong C et al. (2015): Adaptive response in mice exposed to 900 MHz radiofrequency fields: Bleomycin-induced DNA and oxidative damage/repair
Sannino A et al. (2014): Adaptive response in human blood lymphocytes exposed to non-ionizing radiofrequency fields: resistance to ionizing radiation-induced damage
Waldmann P et al. (2013): Influence of GSM Signals on Human Peripheral Lymphocytes: Study of Genotoxicity
Jiang B et al. (2013): Induction of adaptive response in mice exposed to 900MHz radiofrequency fields: application of micronucleus assay
Vijayalaxmi et al. (2013): Incidence of micronuclei in human peripheral blood lymphocytes exposed to modulated and unmodulated 2450 MHz radiofrequency fields
Jiang B et al. (2012): Adaptive Response in Mice Exposed to 900 MHz Radiofrequency Fields: Primary DNA Damage
Karaca E et al. (2012): The genotoxic effect of radiofrequency waves on mouse brain
Hintzsche H et al. (2012): 900 MHz radiation does not induce micronucleus formation in different cell types
Zeni O et al. (2012): Induction of an adaptive response in human blood lymphocytes exposed to radiofrequency fields: Influence of the universal mobile telecommunication system (UMTS) signal and the specific absorption rate
Cao Y et al. (2011): Induction of adaptive response: pre-exposure of mice to 900 MHz radiofrequency fields reduces hematopoietic damage caused by subsequent exposure to ionising radiation
Sannino A et al. (2009): Induction of adaptive response in human blood lymphocytes exposed to radiofrequency radiation
Hansteen IL et al. (2009): Cytogenetic effects of 18.0 and 16.5 GHz microwave radiation on human lymphocytes in vitro
Hansteen IL et al. (2009): Cytogenetic effects of exposure to 2.3 GHz radiofrequency radiation on human lymphocytes in vitro
Zeni O et al. (2008): Evaluation of genotoxic effects in human leukocytes after in vitro exposure to 1950 MHz UMTS radiofrequency field
Vijayalaxmi et al. (2008): Genetic damage in mammalian somatic cells exposed to radiofrequency radiation: a meta-analysis of data from 63 publications (1990-2005)
Scarfi MR et al. (2006): Exposure to radiofrequency radiation (900 MHz, GSM signal) does not affect micronucleus frequency and cell proliferation in human peripheral blood lymphocytes: an interlaboratory study