RF Safe

Electromagnetic fields (UHF) increase voltage sensitivity of membrane ion channels; possible indication of cell phone effect on living cells.

Electromagnetic biology and medicine · 2015 · Mixed · Low evidence

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MixedLow evidencePaper 4561

Using voltage clamp recordings of single OmpF porin channels in an artificial bilayer, exposure to UHF EMF (910–990 MHz) increased channel gating frequency and increased voltage sensitivity, with effects reported as frequency-dependent and maximal at 930 MHz.…

Study snapshot

PublicationElectromagnetic biology and medicine · 2015
Study typein_vitro
Reported directionMixed
Evidence ratingLow

Abstract

The effects of ultra high frequency (UHF) nonionizing electromagnetic fields (EMF) on the channel activities of nanopore forming protein, OmpF porin, were investigated. The voltage clamp technique was used to study the single channel activity of the pore in an artificial bilayer in the presence and absence of the electromagnetic fields at 910 to 990 MHz in real time. Channel activity patterns were used to address the effect of EMF on the dynamic, arrangement and dielectric properties of water molecules, as well as on the hydration state and arrangements of side chains lining the channel barrel. Based on the varied voltage sensitivity of the channel at different temperatures in the presence and absence of EMF, the amount of energy transferred to nano-environments of accessible groups was estimated to address the possible thermal effects of EMF. Our results show that the effects of EMF on channel activities are frequency dependent, with a maximum effect at 930 MHz. The frequency of channel gating and the voltage sensitivity is increased when the channel is exposed to EMF, while its conductance remains unchanged at all frequencies applied. We have not identified any changes in the capacitance and permeability of membrane in the presence of EMF. The effect of the EMF irradiated by cell phones is measured by Specific Absorption Rate (SAR) in artificial model of human head, Phantom. Thus, current approach applied to biological molecules and electrolytes might be considered as complement to evaluate safety of irradiating sources on biological matter at molecular level.

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
PopulationNot supplied
Sample sizeNot supplied
ExposureRF
Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

Using voltage clamp recordings of single OmpF porin channels in an artificial bilayer, exposure to UHF EMF (910–990 MHz) increased channel gating frequency and increased voltage sensitivity, with effects reported as frequency-dependent and maximal at 930 MHz. Channel conductance was unchanged across frequencies, and no changes were identified in membrane capacitance or permeability in the presence of EMF.

Outcomes measured

  • OmpF porin single-channel gating frequency
  • Voltage sensitivity of channel gating
  • Single-channel conductance
  • Membrane capacitance
  • Membrane permeability

Limitations

  • Artificial bilayer/in vitro model (OmpF porin) rather than intact cells or organisms
  • No SAR value reported for the experimental exposure conditions
  • Sample size not stated in the abstract
  • Exposure duration not stated in the abstract
View raw extracted JSON
{
  "study_type": "in_vitro",
  "exposure": {
    "band": "RF",
    "source": "mobile phone",
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": null
  },
  "population": null,
  "sample_size": null,
  "outcomes": [
    "OmpF porin single-channel gating frequency",
    "Voltage sensitivity of channel gating",
    "Single-channel conductance",
    "Membrane capacitance",
    "Membrane permeability"
  ],
  "main_findings": "Using voltage clamp recordings of single OmpF porin channels in an artificial bilayer, exposure to UHF EMF (910–990 MHz) increased channel gating frequency and increased voltage sensitivity, with effects reported as frequency-dependent and maximal at 930 MHz. Channel conductance was unchanged across frequencies, and no changes were identified in membrane capacitance or permeability in the presence of EMF.",
  "effect_direction": "mixed",
  "limitations": [
    "Artificial bilayer/in vitro model (OmpF porin) rather than intact cells or organisms",
    "No SAR value reported for the experimental exposure conditions",
    "Sample size not stated in the abstract",
    "Exposure duration not stated in the abstract"
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "UHF",
    "RF EMF",
    "910 MHz",
    "930 MHz",
    "990 MHz",
    "OmpF porin",
    "nanopore",
    "ion channel",
    "voltage clamp",
    "single-channel activity",
    "gating",
    "conductance",
    "artificial bilayer",
    "SAR",
    "phantom"
  ],
  "suggested_hubs": [
    {
      "slug": "who-icnirp",
      "weight": 0.2,
      "reason": "Mentions SAR and evaluating safety of irradiating sources, but no direct policy/ICNIRP/WHO content in abstract."
    }
  ]
}
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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: 10.3109/15368378.2013.844706
PubMed: 24236537

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