Value chain · CLM-1326
In plain terms
A 1980s US federal health review of animal studies put the onset of harm at about 2 watts absorbed per kilogram of body, mostly from heating. Below about a tenth of that it found few effects and none it judged harmful, though a cancer-promotion result at 2-3 W/kg was unconfirmed.
The claim as recorded
A US Centers for Disease Control staff review of the RF biological-effects literature through 1982, prepared towards proposed occupational limits, concludes that the threshold for adverse effects in experimental animals is about 2 W/kg whole-body SAR. Above 10 W/kg effects were generally adverse (death, severe heat stress, burns, cataracts, tissue lesions, malformations), mostly from body heating. Below 10 W/kg, long exposures could still kill: rats died after 139 minutes at 3.6 W/kg, and the review notes that a sustained body temperature rise of 3-4 degrees C is usually lethal in birds and mammals. The lowest clearly adverse case was bantam chicks at 1.87 W/kg (24 GHz pulsed, 17 mW/cm2, 5 hours a day for 10 days), which staggered, collapsed and avoided the beam. Between 0.17 and 1.87 W/kg there were temperature rises of up to 1.7 degrees C and changes in behaviour, blood, hormones and brain chemistry that the authors did not judge adverse. Below 0.17 W/kg no temperature rise was reported and most exposures had no detectable effect; most reported effects were calcium efflux from the brain, of no known health significance, or blood-brain barrier permeability, which was hard to replicate and may be an artefact. Chronic exposure of mice at 2-3 W/kg brought forward chemically induced skin cancer and spontaneous breast tumours; the review says there is no evidence that RF is itself a carcinogen but at those levels it may act as a promoter or cocarcinogen, unconfirmed and not tested at lower levels.
Evidence behind this: T3 (provisional), a US federal health agency staff review with named authors and a stated screening method; it permits "the review concludes Y". Animal data only. The tabulated literature (Appendix A) is not in the copy held.
Scope and limits
Animal studies only, mostly small mammals; SAR for a given power density depends strongly on frequency and body size, so the 2 W/kg cannot be converted to a single power density. "Adverse" is the authors' own judgement after their own reliability screen; studies above 20 W/kg were not screened. The data appendix and full reference list are missing from this copy, so the underlying studies cannot be checked from it. Undated staff paper, not an adopted limit.
What it assumes
Whole-body average SAR as each cited study reported or as the authors computed it; animal results taken as indicative for setting human limits.
Where it comes from
PDF p.2 (abstract): "THERE APPEARS TO BE A THRESHOLD FOR ADVERSE BIOLOGICAL EFFECTS IN ANIMALS AT A SPECIFIC ABSORPTION RATE (SAR) OF ABOUT 2 W/KG". PDF p.5 / printed -3-: "DEATH WAS REPORTED IN RATS EXPOSED FOR 139 MINUTES AT AN SAR OF ONLY 3.6 W/KG". PDF p.8 / printed -6-: calcium efflux "HAS NO KNOWN SIGNIFICANCE TO THE HEALTH OF THE ANIMAL"; the barrier effect "MAY BE AN EXPERIMENTAL ARTIFACT". PDF p.10 (unnumbered): "THERE IS NO EVIDENCE THAT RF RADIATION IS ITSELF A CARCINOGEN, BUT AT THESE LEVELS IT MAY ACT AS A PROMOTER OR A COCARCINOGEN". PDF p.13, Table 1 row 194-16: 24000 (PW), 17 mW/cm2, 5 hours/day for 10 days, 1.87 W/kg.
Basis: W/kg whole-body SAR; minutes or hours of exposure
Related records
- Answers question
- QST-001 not published in this release
Cite this
energyaperture.com/c/clm-1326
CLM-1326, Energy Aperture, as of 1984.