Effects of Radiofrequency Exposure and Co-Exposure on Human Lymphocytes: Influence of Signal Modulation and Bandwidth

2019 · Mixed · Low evidence

← Research stream

MixedLow evidencePaper 1782

Study snapshot

Publicationmanual · 2019

Study typein_vitro

Reported directionMixed

Evidence ratingLow

Abstract

Effects of Radiofrequency Exposure and Co-Exposure on Human Lymphocytes: Influence of Signal Modulation and Bandwidth Romeo S, Sannino A, Zeni O, Angrisani L, Mass R, Scarfi MR. Effects of radiofrequency exposure and co-exposure on human lymphocytes: The influence of signal modulation and bandwidth. IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology, May 20, 2019. DOI: 10.1109/JERM.2019.2918023 Abstract The occurrence of modulation-specific effects after co-exposures to Radiofrequency (RF) and other agents has been discussed in the literature. In this paper, the influence of modulation and bandwidth in eliciting the DNA damage of RF alone and in combination with mitomycin-C (MMC), is analyzed in human lymphocytes. Blood cultures from healthy donors were exposed to 1950 MHz, and Continuous Wave (CW), Wideband Direct- Sequence Code Division Multiple Access (WCDMA, 4.5 MHz bandwidth), and Additive White Gaussian Noise (AWGN, 9 MHz bandwidth) signals were considered. For each signal, SAR values of 0.15, 0.3, 0.6, 1.25 W/kg were tested. RF exposure alone never induced DNA damage in the micronucleus assay. When RF exposure was followed by MMC treatment, the effect depended on modulation and bandwidth. CW exposure never altered the MMC-induced DNA damage, while such damage was reduced when either signals WCDMA at 0.3 W/kg SAR or AWGN at 0.15 and 0.3 W/kg were applied. These results indicate the influence of modulation for the occurrence of the protective effect, with a relation between the bandwidth and the power absorbed by samples. If confirmed in vivo, clinical applications using modulated RF signals could be devised, to protect cells from side effects of therapeutic treatments. RF electromagnetic fields reduce the DNA damage induced by the chemical agent Mitomycin-C (MMC) in human lymphocytes. The effect is dependent on signal modulation and bandwidth. Conclusions The results of the present investigation provide further evidence that RF exposure can prompt a protective effect in mammalian cells against subsequent genotoxic insults. Moreover, in the current experimental conditions, taking advantage of a systematic comparison with the CW exposure, our findings highlight the modulation scheme and the signal bandwidth as crucial factors for the occurrence of the protective effect. Having said the above, if proved in in vivo models, a new research horizon lies ahead of us, as a potential, innovative clinical application of RF electromagnetic fields, exploiting the protective effect, could be proved. In radio-biology the AR phenomenon has been proposed as a way to protect healthy cells from side effects of chemo/radio-therapeutic treatments, by pre-treatments with low doses of ionizing radiation. However, such proposal never moved into clinical practice due to the risk of cellular transformation as a biological consequence of protracted, low-dose rate exposures to ionizing radiation [35]. The possibility of inducing AR by RF pre- treatments may overcome this issue, due to the non-ionizing nature of these fields. Moreover, RF-induced protection has been here proved to be a tunable phenomenon de-pending on the electromagnetic conditions adopted, which could be able to target different cell types located at different depths in the body. In addition, potential biomedical applications exploiting the protective effect of RF could benefit from the availability of commercially established, low-cost RF sources. Take-Home Messages The innovative feature of RF electromagnetic fields shown here, consists in offering protection to human cells against the damaging action of a chemical agent. The protective effect of RF electromagnetic fields occurs in presence of modulated signals and depends on signal bandwidth, as well as on SAR level. RF-induced protective effect has been here proved, on an in vitro model, to be a tunable phenomenon depending on the electromagnetic conditions adopted, which provides a step towards applications targeting cells located at different depths in the body. These findings suggest the existence of a complex interaction between modulated RF fields and biological systems. Such interaction becomes detectable when samples are appropriately sensitized, such as when RF exposure is combined with other chemical or physical treatments. ieeexplore.ieee.org

Machine Enhanced Logic

AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typein_vitro

Effect directionmixed

PopulationHuman lymphocytes (blood cultures) from healthy donors

Sample sizeNot supplied

ExposureRF · 1950 MHz

Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

Blood cultures were exposed to 1950 MHz RF using CW, WCDMA (4.5 MHz bandwidth), or AWGN (9 MHz bandwidth) signals at SARs 0.15, 0.3, 0.6, and 1.25 W/kg. RF exposure alone did not induce DNA damage in the micronucleus assay. When RF exposure was followed by MMC treatment, CW did not alter MMC-induced DNA damage, while MMC-induced damage was reduced after WCDMA at 0.3 W/kg and after AWGN at 0.15 and 0.3 W/kg, indicating modulation/bandwidth-dependent effects.

Outcomes measured

DNA damage (micronucleus assay)
Mitomycin-C (MMC)-induced DNA damage (co-exposure)

Limitations

In vitro study (human lymphocyte cultures); in vivo relevance not established in the abstract
Sample size/number of donors not reported in the provided text
Exposure duration and other exposure conditions not reported in the provided text
Protective effect observed only under specific modulations/SAR levels; not across all tested conditions

View raw extracted JSON

{
  "study_type": "in_vitro",
  "exposure": {
    "band": "RF",
    "source": null,
    "frequency_mhz": 1950,
    "sar_wkg": null,
    "duration": null
  },
  "population": "Human lymphocytes (blood cultures) from healthy donors",
  "sample_size": null,
  "outcomes": [
    "DNA damage (micronucleus assay)",
    "Mitomycin-C (MMC)-induced DNA damage (co-exposure)"
  ],
  "main_findings": "Blood cultures were exposed to 1950 MHz RF using CW, WCDMA (4.5 MHz bandwidth), or AWGN (9 MHz bandwidth) signals at SARs 0.15, 0.3, 0.6, and 1.25 W/kg. RF exposure alone did not induce DNA damage in the micronucleus assay. When RF exposure was followed by MMC treatment, CW did not alter MMC-induced DNA damage, while MMC-induced damage was reduced after WCDMA at 0.3 W/kg and after AWGN at 0.15 and 0.3 W/kg, indicating modulation/bandwidth-dependent effects.",
  "effect_direction": "mixed",
  "limitations": [
    "In vitro study (human lymphocyte cultures); in vivo relevance not established in the abstract",
    "Sample size/number of donors not reported in the provided text",
    "Exposure duration and other exposure conditions not reported in the provided text",
    "Protective effect observed only under specific modulations/SAR levels; not across all tested conditions"
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "radiofrequency",
    "1950 MHz",
    "SAR",
    "continuous wave",
    "WCDMA",
    "AWGN",
    "bandwidth",
    "signal modulation",
    "human lymphocytes",
    "micronucleus assay",
    "DNA damage",
    "mitomycin-C",
    "co-exposure",
    "adaptive response"
  ],
  "suggested_hubs": []
}

AI can be wrong. Always verify against the paper.

AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.1109/jerm.2019.2918023
PubMed: Not supplied

Read the original paper →

Related papers

← Back to the Research Library