Clastogenic effects of radiofrequency radiations on chromosomes of Tradescantia.

Abstract

The clastogenicity of electromagnetic fields (EMF) has so far been studied only under laboratory conditions. We used the Tradescantia-micronucleus (Trad-MCN) bioassay in an in situ experiment to find out whether short-wave electromagnetic fields used for broadcasting (10-21 MHz) may show genotoxic effects. Plant cuttings bearing young flower buds were exposed (30 h) on both sides of a slewable curtain antenna (300/500 kW, 40-170 V/m) and 15 m (90 V/m) and 30 m (70 V/m) distant from a vertical cage antenna (100 kW) as well as at the neighbors living near the broadcasting station (200 m, 1-3 V/m). The exposure at both sides of the slewable curtain antenna was performed simultaneously within cages, one of the Faraday type shielding the field and one non-shielding mesh cage. Laboratory controls were maintained for comparison. Higher MCN frequencies than in laboratory controls were found for all exposure sites in the immediate vicinity of the antennae, where the exposure standards of the electric field strength of the International Radiation Protection Association (IRPA) were exceeded. The results at all exposure sites except one were statistically significant. Since the parallel exposure in a non-shielding and a shielding cage also revealed significant differences in MCN frequencies (the latter showing no significant differences from laboratory controls), the clastogenic effects are clearly attributable to the short-wave radiation from the antennae.

AI evidence extraction

Main findings

In an in situ Tradescantia-micronucleus bioassay, higher micronucleus (MCN) frequencies than laboratory controls were observed at exposure sites in the immediate vicinity of broadcasting antennae (10–21 MHz), where IRPA electric field strength standards were exceeded; most sites showed statistically significant increases. A parallel exposure using a non-shielding mesh cage versus a Faraday-type shielding cage showed significant differences, with the shielding cage not differing significantly from laboratory controls, supporting attribution of the effect to short-wave radiation from the antennae.

Outcomes measured

• Micronucleus (MCN) frequency (Tradescantia-micronucleus bioassay)
• Clastogenicity / genotoxic effects on chromosomes

Limitations

• Sample size not reported in the abstract.
• Exposure quantified as electric field strength (V/m) and transmitter power; no SAR or absorbed dose reported.
• In situ design may involve uncontrolled environmental factors; details of control of confounding are not provided in the abstract.
• One exposure site did not show statistically significant results (details not provided).

Suggested hubs

• who-icnirp (0.55)
  Mentions IRPA exposure standards being exceeded and relates effects to guideline exceedance.

{
    "study_type": "other",
    "exposure": {
        "band": "RF",
        "source": "broadcasting antenna",
        "frequency_mhz": null,
        "sar_wkg": null,
        "duration": "30 h"
    },
    "population": "Tradescantia plant cuttings bearing young flower buds",
    "sample_size": null,
    "outcomes": [
        "Micronucleus (MCN) frequency (Tradescantia-micronucleus bioassay)",
        "Clastogenicity / genotoxic effects on chromosomes"
    ],
    "main_findings": "In an in situ Tradescantia-micronucleus bioassay, higher micronucleus (MCN) frequencies than laboratory controls were observed at exposure sites in the immediate vicinity of broadcasting antennae (10–21 MHz), where IRPA electric field strength standards were exceeded; most sites showed statistically significant increases. A parallel exposure using a non-shielding mesh cage versus a Faraday-type shielding cage showed significant differences, with the shielding cage not differing significantly from laboratory controls, supporting attribution of the effect to short-wave radiation from the antennae.",
    "effect_direction": "harm",
    "limitations": [
        "Sample size not reported in the abstract.",
        "Exposure quantified as electric field strength (V/m) and transmitter power; no SAR or absorbed dose reported.",
        "In situ design may involve uncontrolled environmental factors; details of control of confounding are not provided in the abstract.",
        "One exposure site did not show statistically significant results (details not provided)."
    ],
    "evidence_strength": "low",
    "confidence": 0.7399999999999999911182158029987476766109466552734375,
    "peer_reviewed_likely": "yes",
    "keywords": [
        "Tradescantia-micronucleus (Trad-MCN)",
        "clastogenicity",
        "genotoxicity",
        "micronuclei",
        "short-wave",
        "radiofrequency",
        "broadcasting",
        "in situ",
        "Faraday shielding",
        "electric field strength",
        "IRPA standards"
    ],
    "suggested_hubs": [
        {
            "slug": "who-icnirp",
            "weight": 0.5500000000000000444089209850062616169452667236328125,
            "reason": "Mentions IRPA exposure standards being exceeded and relates effects to guideline exceedance."
        }
    ]
}

Comments

Log in to comment.

No comments yet.