Effects of Long-Term Exposure of Intermediate Frequency Magnetic Fields (20 kHz, 360 µT) on the Development, Pathological Findings, and Behavior of Female Mice

Bioelectromagnetics · 2021 · Mixed · Low evidence

← Research stream

MixedLow evidencePaper 1128

No differences were reported for body mass development, survival, tumor incidence, 8-arm maze performance, or most open-field endpoints between exposed (20 kHz, 360 µT rms) and sham groups. Rotarod retention times were significantly longer in exposed mice (P …

Study snapshot

PublicationBioelectromagnetics · 2021

Study typeanimal

Reported directionMixed

Evidence ratingLow

Abstract

Effects of Long-Term Exposure of Intermediate Frequency Magnetic Fields (20 kHz, 360 µT) on the Development, Pathological Findings, and Behavior of Female Mice Alexander Lerchl, Karen Drees, Née Grote, Isabel Gronau, Dirk Fischer, Julia Bauch, Axel Hoppe. Effects of Long- Term Exposure of Intermediate Frequency Magnetic Fields (20 kHz, 360 µT) on the Development, Pathological Findings, and Behavior of Female Mice. Bioelectromagnetics. 2021 May;42(4):309-316. doi: 10.1002/bem.22337. Abstract The use of magnetic fields in the intermediate-frequency (IF) range to wirelessly charge electric cars with power transfer in the kilowatt range has become increasingly widespread, leading to unavoidable stray fields in the microtesla range. Only a handful of studies have assessed the potential biological risks associated with exposure to such fields. We exposed female mice (n = 80 per group) to either 20 kHz, 360 µT (rms), or sham in Helmholtz coils to conduct a blind design study. Exposure started at 3 months of age (24 h/day). Body mass was recorded every 1-2 weeks. At 10 months of age, three behavioral tests were performed on 24 animals per group. Three months later, the mice were sacrificed and organs (brain, liver, kidney, spleen, and lung) were removed and prepared for microscopic analysis. Our findings demonstrate no differences in the development of body mass and survival rates (96% and 89%, respectively). Similarly, no significant differences were observed in tumor incidence rates. When it comes to behavioral tests, the 8-arm maze results revealed no significant differences. In contrast, the Rotarod data were significantly (P < 0.001) different with longer retention times seen in the exposed mice. In the open field, the number of supported rears was significantly lower (P < 0.01), whereas the other endpoints did not show any differences. Overall, our data reveal no adverse effects of exposure to 20 kHz, 360 µT on the development and tumor incidences, while the significant differences in the behavioral tests may indicate higher levels of alertness in mice. pubmed.ncbi.nlm.nih.gov

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 typeanimal

Effect directionmixed

PopulationFemale mice

Sample size160

ExposureIF · 0.02 MHz · 24 h/day; from 3 months of age to sacrifice ~13 months of age

Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

Outcomes measured

Body mass development
Survival
Tumor incidence
Behavioral tests (8-arm maze)
Behavioral tests (Rotarod)
Behavioral tests (open field; supported rears and other endpoints)
Microscopic pathology of brain, liver, kidney, spleen, lung

Limitations

Animal study (female mice); generalizability to humans not addressed in abstract
Exposure scenario uses Helmholtz coils; may not capture all real-world wireless-charging exposure characteristics
Behavioral testing conducted on a subset (24 animals per group)

View raw extracted JSON

{
  "study_type": "animal",
  "exposure": {
    "band": "IF",
    "source": "wireless charging (electric cars) stray fields (modeled in Helmholtz coils)",
    "frequency_mhz": 0.02,
    "sar_wkg": null,
    "duration": "24 h/day; from 3 months of age to sacrifice ~13 months of age"
  },
  "population": "Female mice",
  "sample_size": 160,
  "outcomes": [
    "Body mass development",
    "Survival",
    "Tumor incidence",
    "Behavioral tests (8-arm maze)",
    "Behavioral tests (Rotarod)",
    "Behavioral tests (open field; supported rears and other endpoints)",
    "Microscopic pathology of brain, liver, kidney, spleen, lung"
  ],
  "main_findings": "No differences were reported for body mass development, survival, tumor incidence, 8-arm maze performance, or most open-field endpoints between exposed (20 kHz, 360 µT rms) and sham groups. Rotarod retention times were significantly longer in exposed mice (P < 0.001), and supported rears in the open field were significantly lower (P < 0.01).",
  "effect_direction": "mixed",
  "limitations": [
    "Animal study (female mice); generalizability to humans not addressed in abstract",
    "Exposure scenario uses Helmholtz coils; may not capture all real-world wireless-charging exposure characteristics",
    "Behavioral testing conducted on a subset (24 animals per group)"
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "intermediate frequency",
    "magnetic fields",
    "20 kHz",
    "360 µT",
    "wireless power transfer",
    "electric car charging",
    "Helmholtz coils",
    "mouse",
    "tumor incidence",
    "behavior",
    "Rotarod",
    "open field",
    "8-arm maze"
  ],
  "suggested_hubs": [
    {
      "slug": "wireless-charging",
      "weight": 0.86,
      "reason": "Study motivated by stray intermediate-frequency magnetic fields from wireless charging of electric cars."
    }
  ]
}

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: 10.1002/bem.22337
PubMed: 33822410

Read the original paper →

Related papers

← Back to the Research Library