Table 1.
Combined exposure to ELF magnetic field and heat: studies reporting on a potentiation of heat-induced effects.
| Reference | Model system | Exposure conditions | Thermal stress conditions | End point (s) | Outcome of coexposure | Comments |
|---|---|---|---|---|---|---|
| (54) | Human adenocarcinoma cells (HeLa) | 60 Hz | 43°C | Luciferase gene expression in cells transfected with HSP70 promoter | Synergistic effect (luciferase gene expression) | Increased luciferase expression after MF alone |
| 80 µT | 20 min | |||||
| 20 min | Concurrent | |||||
| (42) | Endothelial cells from pig pulmonary arteries (SPAE) | 50 Hz | 44°C | mRNA level and synthesis of HSP70 | Enhanced accumulation and translation of the heat-induced HSP70 mRNA | MF induced an increased level of inducible HSP70 in endothelial, lymphoma, and leukemia cells. No effect in human fibroblasts |
| 680 µT | 30 min | |||||
| 24 h | Postexposure | |||||
| (47) | Human myeloid leukemia HL-60 cells | 50 Hz | 43°C | mRNA level and synthesis of HSP70A/B/C; HSC70; HSP27, 60, 75, and 90 (α and β) | Strong induction in HSP70 gene family in the interval 40–80 µT | Increased HSP70 mRNA levels and synthesis after MF alone |
| 10–140 µT | 30 min | |||||
| 30 min | Concurrent | |||||
| (55) | Breast MCF 7 and cervical HeLa (cancer); breast epithelium HBL-100 (healthy) | 50 Hz train pulsed MF (2 s burst and 1 s rest) | 40°C | HSP70 synthesis, cell proliferation | Increased HSP70 by MF under thermal stress in both healthy and cancer cells | No effects of MF alone |
| 42°C | ||||||
| Concurrent | ||||||
| 34 mT | ||||||
| 0–12 h | ||||||
| (57) | Drosophila wild-type CS and mutant w1118 flies | 50 Hz | 35°C | Death rate, life span, locomotion, HSP 22/26/70 mRNA levels, oxidative stress | MF enhanced thermal stress effects | Some gender differences, sporadic MF effect at 25°C |
| 3 mT | Concurrent | |||||
| 2 and 24 h | ||||||
| (56) | Transgenic C. elegans | 50 Hz | 28 and 29°C | Expression of HSP16 and 70 promoters upstream of lacZ at 100 µT | EMF enhanced the lacZ reporter gene expression under the control of HSP16 or 70 promoters | No effect of MF alone |
| 50, 100 µT | Concurrent | |||||
| 1 h | ||||||
| (58) | Wistar rats | 60 Hz | 43°C for 12 min before MF | Histopathological and histomorphometrical analysis of rat testes | MF aggravates the effects of thermal stress | |
| 1 mT | ||||||
| 15, 30, 60 days | ||||||
| (59) | Drosophila melanogaster | 50 Hz | 34–37°C | Embryogenesis anomalies | MF aggravates the anomalies due to thermal stress | |
| 100 µT | Concurrent | |||||
| 30 min | ||||||