Quantitative changes in potassium, sodium, and calcium in the submaxillary salivary gland and blood serum of rats exposed to 2880-MHz microwave radiation.

PAPER pubmed Bioelectromagnetics 1983 Animal study Effect: harm Evidence: Low

Read original paper → DOI: 10.1002/bem.2250040106 PMID: 6838667 Evidence Lab

Abstract

Na+, K+, and Ca2+ concentrations in the blood serum and submaxillary salivary gland (SSG) were investigated in adult, male rats exposed to 2880-MHz microwaves modulated with 1.5-mus pulses at a pulse repetition rate of 1000 Hz or in a hyperthermal environment. Rats were exposed, one at a time, for 30 min to microwaves producing a specific absorption rate (SAR) of: 4.2, 6.3, 6.8, 8.4, 10.8, or 12.6 W/kg, or were sham exposed under similar environmental conditions. In a second series, one group of rats was exposed singly for 15, 30, or 60 min to microwaves producing an SAR of 9.5 W/kg and other rats were exposed for similar periods at 40 degrees C; and 10 rats were sham exposed. Flame photometric analysis indicated that the thresholds of microwave radiation required to induce a change in Na+, K+, and Ca2+ concentrations in the salivary glands are 6.8, 6.8, and 6.3 W/kg, respectively. The directions of Na+, K+, and Ca2+ ion shifts in exposed rats' salivary glands are similar, whether affected by microwaves or hyperthermia. Greater changes in Na+ and K+ concentrations in SSG of rats exposed to microwaves for 15 and 30 min were found than in those exposed at 40 degrees C. On the other hand, exposure to hyperthermia at 40 degrees C or to microwaves for 1 h caused Na+ concentration to be increased by 68.7 and 59.5% and K+ concentration to be decreased by 29.6 and 21.7%, respectively.

AI evidence extraction

At a glance

Study type

Animal study

Effect direction

harm

Population

Adult, male rats

Sample size

—

Exposure

microwave · 2880 MHz · 15, 30, or 60 min (also 30 min in dose-response series)

Evidence strength

Low

Confidence: 74% · Peer-reviewed: yes

Main findings

Adult male rats were exposed to 2880-MHz pulsed microwaves at various SARs and durations, with sham exposure and a 40°C hyperthermia comparison. Flame photometry suggested SAR thresholds for changes in salivary gland ions of 6.8 W/kg (Na+), 6.8 W/kg (K+), and 6.3 W/kg (Ca2+). Ion shift directions in salivary glands were reported as similar for microwave exposure and hyperthermia; at 1 h, Na+ increased (59.5% microwaves; 68.7% hyperthermia) and K+ decreased (21.7% microwaves; 29.6% hyperthermia).

Outcomes measured

Na+ concentration (submaxillary salivary gland)
K+ concentration (submaxillary salivary gland)
Ca2+ concentration (submaxillary salivary gland)
Na+ concentration (blood serum)
K+ concentration (blood serum)
Ca2+ concentration (blood serum)

Limitations

Sample size not reported in abstract (except mention of 10 sham-exposed rats in second series).
Outcome details for blood serum changes are not described in the abstract.
Potential thermal confounding noted via hyperthermia comparison; separation of thermal vs non-thermal effects is not fully established in abstract.
Randomization/blinding not described in abstract.

View raw extracted JSON

{
    "study_type": "animal",
    "exposure": {
        "band": "microwave",
        "source": null,
        "frequency_mhz": 2880,
        "sar_wkg": null,
        "duration": "15, 30, or 60 min (also 30 min in dose-response series)"
    },
    "population": "Adult, male rats",
    "sample_size": null,
    "outcomes": [
        "Na+ concentration (submaxillary salivary gland)",
        "K+ concentration (submaxillary salivary gland)",
        "Ca2+ concentration (submaxillary salivary gland)",
        "Na+ concentration (blood serum)",
        "K+ concentration (blood serum)",
        "Ca2+ concentration (blood serum)"
    ],
    "main_findings": "Adult male rats were exposed to 2880-MHz pulsed microwaves at various SARs and durations, with sham exposure and a 40°C hyperthermia comparison. Flame photometry suggested SAR thresholds for changes in salivary gland ions of 6.8 W/kg (Na+), 6.8 W/kg (K+), and 6.3 W/kg (Ca2+). Ion shift directions in salivary glands were reported as similar for microwave exposure and hyperthermia; at 1 h, Na+ increased (59.5% microwaves; 68.7% hyperthermia) and K+ decreased (21.7% microwaves; 29.6% hyperthermia).",
    "effect_direction": "harm",
    "limitations": [
        "Sample size not reported in abstract (except mention of 10 sham-exposed rats in second series).",
        "Outcome details for blood serum changes are not described in the abstract.",
        "Potential thermal confounding noted via hyperthermia comparison; separation of thermal vs non-thermal effects is not fully established in abstract.",
        "Randomization/blinding not described in abstract."
    ],
    "evidence_strength": "low",
    "confidence": 0.7399999999999999911182158029987476766109466552734375,
    "peer_reviewed_likely": "yes",
    "keywords": [
        "microwave radiation",
        "2880 MHz",
        "pulsed modulation",
        "SAR",
        "rats",
        "submaxillary salivary gland",
        "blood serum",
        "sodium",
        "potassium",
        "calcium",
        "hyperthermia"
    ],
    "suggested_hubs": []
}

AI can be wrong. Always verify against the paper.

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

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