Medical/biological study (experimental study)

Terahertz radiation increases genomic instability in human lymphocytes med./bio.

By: Korenstein-Ilan A, Barbul A, Hasin P, Eliran A, Gover A, Korenstein R

Published in: Radiat Res 2008; 170 (2): 224-234

Aim of study (acc. to author)

To explore the genetic and epigenetic consequences of exposing dividing human peripheral lymphocytes to low-intensity continuous wave 0.1 THz irradiation. Aneuploidy of the chromosomes as well as replication timing and synchronization of the centromeres were examined.

Background/further details

Increased levels of aneuploidy and asynchronous replication are typical of both hematological malignancies and various solid tumors. Lymphocytes were obtained from nine male volunteers. Three groups were examined: a control group that was undisturbed for the duration of the culturing, a sham-exposed group and an exposed sample. To ascertain that the effects induced by exposing the cells were not thermal, temperature rise was monitored during exposure.

Endpoint

genotoxicity/mutation: genomic instability (aneuploidy and changes in replication timing and synchronization of their centromeres)

Exposure

- 0.1 THz
- millimeter waves
- TeraHz
- CW continuous wave

Exposure	Parameters
Exposure 1: 0.1 THz Modulation type: CW Exposure duration: continuous for 1 h, 2 h or 24 h	power density: 0.031 mW/cm² SAR: 2.4 mW/g

Exposure 1

Main characteristics

Frequency	0.1 THz
Type	electric field
Polarization	linear
Exposure duration	continuous for 1 h, 2 h or 24 h

Modulation

Modulation type	CW

Exposure setup

Exposure source	cylindrical corrugated waveguide
Distance between exposed object and exposure source	28 cm
Setup	33.4 cm long waveguide with an inner diameter of 3.8 cm placed inside a temperature controlled incubator; inner walls of incubator covered with pyramidal radiation-absorbing material
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power density	0.031 mW/cm²	-	calculated	-	-
SAR	2.4 mW/g	-	calculated	-	-

Exposed system:

intact cell/cell culture

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: genomic instability (aneuploidy [chromosomes 1,10, 11, 17] and changes in replication timing and synchronization of their centromeres [FISH])

Investigated system:

DNA/RNA
chromosomes

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The present study suggests the existence of genetic instability, reflected by increased levels of aneuploidy and increased levels of asynchronous replication of centromeres, in lymphocytes due to exposure to 0.1 THz continous wave radiation. Chromosomes 11 and 17 were most vulnerable (about 30% increase in aneuploidy after 2 and 24 h of exposure) due to exposure, while chromosomes 1 and 10 were not affected. There were changes in the asynchronous mode of replication of centromeres 11, 17 and 1 (by 40%) after 2 h of exposure and in the centromeres of all four chromosomes after 24 h of exposure (by 50%).

Study character:

medical/biological study
experimental study
full/main study

Study funded by

European Union (EU)/European Commission
Ministry of Science and Technology, Israel
Quality of Life and Management of Living Resources program of European Union

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