RF Safe

Effects of mobile phone electromagnetic fields at nonthermal SAR values on melatonin and body weight of Djungarian hamsters (Phodopus sungorus).

Journal of pineal research · 2008 · Mixed · Moderate evidence

← Research stream
MixedModerate evidencePaper 5021

Across three experiments (383, 900, 1800 MHz; TETRA/GSM modulation) at whole-body averaged SAR 80 mW/kg for 60 days, pineal and serum melatonin levels and organ weights (testes, brain, kidneys, liver) were not affected versus sham. Body weight increased at 38…

Study snapshot

PublicationJournal of pineal research · 2008
Study typeanimal
Reported directionMixed
Evidence ratingModerate

Abstract

In three experiments, adult male Djungarian hamsters (Phodopus sungorus) were exposed 24 hr/day for 60 days to radio frequency electromagnetic fields (RF-EMF) at 383, 900, and 1800 MHz, modulated according to the TETRA (383 MHz) and GSM standards (900 and 1800 MHz), respectively. A radial waveguide system ensured a well defined and uniform exposure at whole-body averaged specific absorption rates of 80 mW/kg, which is equal to the upper limit of whole-body exposure of the general population in Germany and other countries. For each experiment, using two identical waveguides, hamsters were exposed (n = 120) and sham-exposed (n = 120) in a blind fashion. In all experiments, pineal and serum melatonin levels as well as the weights of testes, brain, kidneys, and liver were not affected. At 383 MHz, exposure resulted in a significant transient increase in body weight up to 4%, while at 900 MHz this body weight increase was more pronounced (up to 6%) and not transient. At 1800 MHz, no effect on body weight was seen. The results corroborate earlier findings which have shown no effects of RF-EMF on melatonin levels in vivo and in vitro. The data are in accordance with the hypothesis that absorbed RF energy may result in metabolic changes which eventually cause body weight increases in exposed animals. The data support the notion that metabolic effects of RF-EMFs need to be investigated in more detail in future studies.

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
PopulationAdult male Djungarian hamsters (Phodopus sungorus)
Sample size240
ExposureRF · 0.08 W/kg · 24 hr/day for 60 days
Evidence strengthModerateConfidence: 78% · Peer reviewed: yes

Main findings

Across three experiments (383, 900, 1800 MHz; TETRA/GSM modulation) at whole-body averaged SAR 80 mW/kg for 60 days, pineal and serum melatonin levels and organ weights (testes, brain, kidneys, liver) were not affected versus sham. Body weight increased at 383 MHz (significant transient increase up to 4%) and at 900 MHz (more pronounced increase up to 6% and not transient), while no body weight effect was seen at 1800 MHz.

Outcomes measured

  • Pineal melatonin levels
  • Serum melatonin levels
  • Body weight
  • Testes weight
  • Brain weight
  • Kidneys weight
  • Liver weight

Limitations

  • Mechanistic interpretation (metabolic changes) is presented as a hypothesis rather than directly measured
  • Frequency-dependent effects observed (body weight changes at 383/900 MHz but not 1800 MHz), which may limit generalization across RF exposures
View raw extracted JSON
{
  "study_type": "animal",
  "exposure": {
    "band": "RF",
    "source": "mobile phone",
    "frequency_mhz": null,
    "sar_wkg": 0.08,
    "duration": "24 hr/day for 60 days"
  },
  "population": "Adult male Djungarian hamsters (Phodopus sungorus)",
  "sample_size": 240,
  "outcomes": [
    "Pineal melatonin levels",
    "Serum melatonin levels",
    "Body weight",
    "Testes weight",
    "Brain weight",
    "Kidneys weight",
    "Liver weight"
  ],
  "main_findings": "Across three experiments (383, 900, 1800 MHz; TETRA/GSM modulation) at whole-body averaged SAR 80 mW/kg for 60 days, pineal and serum melatonin levels and organ weights (testes, brain, kidneys, liver) were not affected versus sham. Body weight increased at 383 MHz (significant transient increase up to 4%) and at 900 MHz (more pronounced increase up to 6% and not transient), while no body weight effect was seen at 1800 MHz.",
  "effect_direction": "mixed",
  "limitations": [
    "Mechanistic interpretation (metabolic changes) is presented as a hypothesis rather than directly measured",
    "Frequency-dependent effects observed (body weight changes at 383/900 MHz but not 1800 MHz), which may limit generalization across RF exposures"
  ],
  "evidence_strength": "moderate",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "RF-EMF",
    "radiofrequency",
    "TETRA",
    "GSM",
    "383 MHz",
    "900 MHz",
    "1800 MHz",
    "SAR 80 mW/kg",
    "melatonin",
    "pineal",
    "serum melatonin",
    "body weight",
    "Djungarian hamster",
    "Phodopus sungorus",
    "nonthermal"
  ],
  "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: 10.1111/j.1600-079x.2007.00522.x
PubMed: 18339122

Read the original paper →

Related papers

← Back to the Research Library