Answers to the comments of A. Lerchl on the paper ''No effects of intermittent 50-Hz EMF on cytoplasmic free calcium and on the mitochondrial membrane potential in human diploid fibroblasts'' by Pilger et al. (Radiat Environ Biophys (2004) 43:203-207)

摘要: Dr. Lerchl expresses his concern about the low variability of results from comet assay reported in our publication (Pilger et al. 2004). He argues that findings are suspicious for statistical as well technical reasons. In addition, he suspects blinding experiments could have been circumvented. These allegations mainly derived controversies context with highfrequency electromagnetic fields (Lerchl and Wilhelm 2010; Rudiger Adlkofer 2009a, b; 2009). However, it should be pointed out that, apart objections raised by Lerchl, Rudiger’s group on genotoxic effects extremely low-frequency (ELF-EMF) were unexpected a completely different sense. contrast to expectations, intermittent exposure ELF-EMF was found induce DNA strand breaks, whereas no changes fragmentation observed upon treatment continuous (Ivancsits 2002). Recently, this phenomenon which seems lack biological plausibility corroborated Focke (2010) using same cells system. One main reasons Lerchl’s claim data tail factors must fabricated is rooted argument one E-cell classification more or less would result much greater variation than standard deviation 0.04. resulting range assuming factor 4.08 3.985–4.175. fundamentally flawed. There cannot miraculous addition loss but cell balanced reduction exhibiting another type. The most likely case D-cell vice versa. By simple arithmetic, an effect 0.03 not threefold higher figure 0.095 given Lerchl. It has borne mind five types A E have, under assumption only random variation, multinomial distribution variance each type count proportional p(1 p), where p probability observing Under control conditions, fraction E-cells very (about 0.0015). Hence, average number among 1,000 1.5, theoretical 1.22. Single counts paper 2004) retrieved, kept file, examination records fibroblast controls (n = 50) yielded 1.25 E-cells. This value quite close expectation. statement ‘‘The 5 replicates mean also significant since change 0.04’’ correct, incomprehensible how arrived at statement. deviation—under conditions stated Lerchl—will according following formula: