Perhaps this issue may have come originally from the EU Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR)
Report on Light Sensitivity in 2008.
The Abstract reads:
Quote:
SCENIHR did not find suitable direct scientific data on the relationship between energy saving lamps and the symptoms in patients with various conditions (i.e xeroderma pigmentosum, lupus, migraine, epilepsy, myalgic encephalomyelitis, Irlen-Meares syndrome, fibromyalgia, electrosensitivity, AIDS/HIV, dyspraxia, and autism). Therefore, SCENIHR examined whether three lamp characteristics (flicker, electromagnetic fields, and UV/blue light emission) could act as triggers for disease symptoms. Due to lack of data on CFLs, existing data on traditional fluorescent tubes were extrapolated to situations when compact fluorescent lamps may be used.
While for some conditions either flicker and/or UV/blue light could exacerbate symptoms, there is no reliable evidence that the use of fluorescent tubes was a significant contributor. Of all compact fluorescent lamps properties, only UV/blue light radiation was identified as a potential risk factor for the aggravation of the light-sensitive symptoms in some patients with such diseases as chronic actinic dermatitis and solar urticaria.
The committee wishes to draw attention of the Commission Services to the fact that it has been observed that some single-envelope CFLs emit UVB and traces of UVC radiation. Under extreme conditions (i.e. prolonged exposures at distances <20 cm) these CFLs may lead to UV exposures approaching the current workplace limit set to protect workers from skin and retinal damage.
...
The committee notes that the use of double-envelope energy saving bulbs or similar technology would largely or entirely mitigate both the risk of approaching workplace limits on UV emissions in extreme conditions and the risk of aggravating the symptoms of light-sensitive individuals.
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Flourescent lamps usually produce a spectrum with two
UVC emission lines (253.7 nm and 185 nm) caused by inelastic scattering/impact ionisation emissions in the mercury plasma. (The rest of the emissions from a bulb are determined by the phosphor coating and the glass envelope. There's probably a reasonable variance amongst different types/brands, because of the variations in the materials used ??).
From the same source:
Quote:
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Some single-envelope CFLs emit UV-B and traces of UV-C radiation at wavelength of 254 nm, which is not the case for incandescent lamps (Khazova and O ́Hagan 2008). Experimental data show that CFLs produce more UVA irradiance than a tungsten lamp. Furthermore, the amount of UVB irradiance produced from single-envelope CFLs, from the same distance of 20 cm, was about ten times higher than that irradiated by a tungsten lamp (Moseley and Ferguson 2008).
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Mind you, the Moseley & Ferguson source they quote above, is listed as 'Personal Communication' and is very difficult to find on the web.
Cheers