研究のタイプ: 医学／生物学の研究 (experimental study)

[ヒト白血球の熱ショックタンパク質の非熱的誘導に対する900 MHz電磁界の影響] med./bio.

Effect of 900 MHz electromagnetic fields on nonthermal induction of heat-shock proteins in human leukocytes

著者: Lim HB, Cook GG, Barker AT, Coulton LA
掲載誌: Radiat Res 2005; 163 (1): 45-52
RISフォーマットで参考文献をダウンロード

この研究は、携帯電話タイプの電磁放射へのばく露がヒト白血球に非熱的ストレス反応を引き起こすか否かを調べた。ヒト末梢血に、異なるばく露時間（20分、1時間、4時間）、3レベルの平均比吸収率（0.4、2.0、3.6 W / kg）で、900 MHz RF（連続波またはGSM変調）信号へのばく露または擬似ばく露を与えた。ばく露は、インキュベータ内に置かれたTEMセル内で行った。インキュベータ内は、37 °C、95 %空気/ 5 %CO2で適切に制御された。陽性（42 ℃の熱ストレスを受けた）および陰性（37 ℃に保たれた）対照群を同じインキュベータ内で同時にインキュベートした。結果として、熱は、ストレスタンパク質（HSP70、HSP27）を発現している細胞の数の増加させた；この増加は時間に依存した；一方、RF電磁界ばく露後にストレスタンパク質を発現している細胞の数には有意差がなかった；これらの知見は、軽度の加熱とは対照的に、携帯電話タイプの電磁放射は正常なヒトリンパ球および単球のストレッサーではないことを示す、と報告している。

The detailed summary of this article is not available in your language or incomplete. Would you like to see a complete translation of the summary? Then please contact us →

研究目的（著者による）

To study whether exposure to mobile phone-type irradiation causes a nonthermal stress response in human leukocytes.

詳細情報

Positive (heat-stressed at 42°C) and negative (kept at 37°C) control samples were incubated simultaneously.

影響評価項目

ばく露

ばく露 パラメータ
ばく露1: 900 MHz
Modulation type: CW
ばく露時間: continuous for 4 hours
This study was performed to investigate the effects of different power levels.
  • SAR: 0.4 W/kg mean (unspecified) (input power level of 3 W)
  • SAR: 2 W/kg mean (unspecified) (input power level of 14 W)
  • SAR: 3.6 W/kg mean (unspecified) (input power level of 25 W)
ばく露2: 900 MHz
Modulation type: CW
ばく露時間: continuous for 20 min, 1 h or 4 h
This study was performed to investigate the effects of different exposure durations.
  • SAR: 2 W/kg mean (unspecified)
ばく露3: 900 MHz
Modulation type: pulsed
ばく露時間: continuous for 20 min, 1 h or 4 h
This study was performed to investigate the effects of different exposure durations using a GSM signal.
  • SAR: 0.4 W/kg mean (unspecified)

ばく露1

主たる特性
周波数 900 MHz
タイプ
  • electromagnetic field
ばく露時間 continuous for 4 hours
Additional information This study was performed to investigate the effects of different power levels.
Modulation
Modulation type CW
ばく露装置
ばく露の発生源／構造
ばく露装置の詳細 The human peripheral blood was exposed or sham-exposed in Petri dishes in a calibrated TEM cell placed in an incubator. The cell was operated in travelling wave mode, being terminated by a matched load, which increased the uniformity of the exposure.
Additional information Positive (heat-stressed at 42°C) and negative (kept at 37°C) control groups were incubated simultaneously in the same incubator. The sham-exposed dish and the positive control were heated by heater mats, the negative control was in equilibrium with the incubator temperature. The peak static magnetic flux density generated by the heater mat and measured 2 mm above the mat using an incremental gaussmeter was below 15 µT.
パラメータ
測定量 値 種別 Method Mass 備考
SAR 0.4 W/kg mean 測定値および計算値 unspecified input power level of 3 W
SAR 2 W/kg mean 測定値および計算値 unspecified input power level of 14 W
SAR 3.6 W/kg mean 測定値および計算値 unspecified input power level of 25 W
Additional parameter details

The standard deviation of the FDTD-predicted SAR was about 43% of the mean.

測定および計算の詳細

The mean SAR experienced by the exposed blood cells was predicted using a specifically developed FDTD modelling software. A detailed description of this dosimetry can be found in the reference article. The FDTD-predicted results were in good agreement with those published for a slightly different geometry and with SAR values calculated from thermal measurements. The reading of an ammeter measuring the input current of the power amplifier was used as a surrogate for the input power applied to the TEM cell.

ばく露2

主たる特性
周波数 900 MHz
タイプ
  • electromagnetic field
ばく露時間 continuous for 20 min, 1 h or 4 h
Additional information This study was performed to investigate the effects of different exposure durations.
Modulation
Modulation type CW
ばく露装置
ばく露の発生源／構造
  • E1と同じ装置
パラメータ
測定量 値 種別 Method Mass 備考
SAR 2 W/kg mean 計算値 unspecified -

ばく露3

主たる特性
周波数 900 MHz
タイプ
  • electromagnetic field
ばく露時間 continuous for 20 min, 1 h or 4 h
Additional information This study was performed to investigate the effects of different exposure durations using a GSM signal.
Modulation
Modulation type pulsed
Duty cycle 12.5 %
ばく露装置
ばく露の発生源／構造
  • E1と同じ装置
パラメータ
測定量 値 種別 Method Mass 備考
SAR 0.4 W/kg mean 計算値 unspecified -

Reference articles

  • Lim HB et al. (2002): [携帯電話からの近傍界がヒト全血のストレス反応メカニズムに与える影響を定量化するためのRFドシメトリ装置のFDTD構造]

ばく露を受けた生物:

方法 影響評価項目／測定パラメータ／方法

研究対象とした生物試料:
調査の時期:
  • ばく露後

研究の主なアウトカム（著者による）

Heat caused an increase in the number of cells expressing stress proteins (HSP70, HSP27) and this increase was dependent on time. However, no statistically significant difference was detected in the number of cells expressing stress proteins after exposure. These data suggest that mobile phone-type irradiation is not a stressor of normal human lymphocytes and monocytes, in contrast to mild heating.

研究の種別:

研究助成

関連論文