A preliminary investigation into the effect of exposure of photosensitive individuals to light from compact fluorescent lamps

Summary Background  Compact fluorescent lamps (CFLs) are due to replace common incandescent lamps over the next few years. There has been no investigation of the possible effect of this on patients with photosensitive disorders. Objectives  To determine the effect of exposure of photosensitive individuals to light from CFLs. Methods  The spectral emission from a sample of CFLs was measured using a calibrated spectroradiometer. The erythemal response was determined in one normal individual and four photosensitive individuals by direct exposure of the skin to light from a CFL. The susceptibility of a wider group of photosensitive individuals was predicted based on the light dose known to elicit a reaction during phototesting at discrete ultraviolet (UV) wavelengths. Results  CFLs emit UV radiation at wavelengths down to 254 nm. Prolonged exposure of a normal individual’s skin produced erythema. However, an exposure of only 2·5 min at 5 cm elicited marked erythema in one of the abnormally photosensitive patients. Conclusions  CFLs could be a source of harmful UV radiation to photosensitive individuals. Patients with chronic actinic dermatitis are thought to be at greatest risk. The use of a protective envelope is recommended.     

Leonard Bell Cox (1894–1976) – pioneer of Australian clinical neurology

The name of Leonard Bell Cox (1894–1976) will long be associated with a number of very significant areas in the intellectual and cultural life of the Australian State of Victoria. A quarter of a century after his death, his cultural achievements, and the enduring products of these achievements, continue to be celebrated in his native city, Melbourne. However his enormous contributions in these cultural fields were matched by his perhaps less widely known achievements in medicine, in particular in the neurosciences. In his time he not only pioneered the foundation and progressive development of the speciality of clinical neurology in Australia, but at the same time became a recognised world expert on the pathology of brain tumours.     

Inhibition of monocyte esterase activity by organophosphate insecticides

Organophosphate insecticides, such as Vapona, Naled, and Rabon, are highly potent inhibitors of an enzyme found in human monocytes. The enzyme, a specific monocyte esterase, could be inhibited by Vapona in blood samples via airborne contamination at levels easily achieved from commercial slow-release insecticide strips. Fifty percent inhibition (I50)--as measured on the Hemalog D (Technicon Corp.)--occurred at solution concentrations of 0.22, 1.5, and 2.6 X 10(-6) g/liter for Vapona, Rabon, and Naled, respectively. Parathion (a thiophosphate) and Baygon (a carbamate) were less potent, with I50 values of 3.7 X 10(-5) and 1.5 X 10(-4) g/liter, respectively. Dursban (another thiophosphate) and Carbaryl (a carbamate) showed only marginal inhibition. Eserine, malathion, nicotine and pyrethrum had no inhibitory effect up to 0.5 g/liter. The occurrence of this effect in vivo has not yet been shown, nor is it clear what the implications of such an effect would be. The inhibition of this enzyme by airborne contaminants, however, may interfere with the proper functioning of the Hemalog D.