Electromagnetic fields produced by incubators influence heart rate variability in newborns.

BACKGROUND: Incubators are largely used to preserve preterm and sick babies from postnatal stressors, but their motors produce high electromagnetic fields (EMFs). Newborns are chronically exposed to these EMFs, but no studies about their effects on the fragile developing neonatal structure exist. AIM: To verify whether the exposure to incubator motor electric power may alter autonomous nervous system activity in newborns. MATERIAL AND METHODS: Heart rate variability (HRV) of 43 newborns in incubators was studied. The study group comprised 27 newborns whose HRV was studied throughout three 5-minute periods: with incubator motor on, off, and on again, respectively. Mean HRV values obtained during each period were compared. The control group comprised 16 newborns with constantly unrecordable EMF and exposed to changes in background noise, similar to those provoked by the incubator motor. RESULTS: Mean (SD) total power and the high-frequency (HF) component of HRV increased significantly (from 87.1 (76.2) ms2 to 183.6 (168.5) ms2) and the mean low-frequency (LF)/HF ratio decreased significantly (from 2.0 (0.5) to 1.5 (0.6)) when the incubator motor was turned off. Basal values (HF = 107.1 (118.1) ms2 and LF/HF = 1.9 (0.6)) were restored when incubators were turned on again. The LF spectral component of HRV showed a statistically significant change only in the second phase of the experiment. Changes in background noise did not provoke any significant change in HRV. CONCLUSION: EMFs produced by incubators influence newborns' HRV, showing an influence on their autonomous nervous system. More research is needed to assess possible long-term consequences, since premature newborns may be exposed to these high EMFs for months.

Reduction of exposure of newborns and caregivers to very high electromagnetic fields produced by incubators.

The aims of this paper is to measure whether ferromagnetic panels sufficiently reduce the high electromagnetic fields (EMF) to which newborns are exposed in incubators and to which caregivers are exposed when working near the incubators. We measured EMF at mattress level in three neonatal incubators with and without ferromagnetic panels between the electric motor and the mattress. We then measured the EMF at the level of the maximum emission point for caregivers, i.e., near the display panel. The ferromagnetic panels were (a) 5 mm thick iron, (b), (c), (d) respectively, one, two, and three sheets of 0.3 mm thick mu-metal. The weight of iron sheet was 4 g/cm2, and mu-metal 0.2 g/cm2. The use of the ferromagnetic panels significantly reduced the EMF. No significant difference in attenuation was recorded using one, two, or, three sheets of mu-metal, or a single sheet of iron. One, two, and three sheets of mu-metal reduced EMFs by 77%, 82%, and 84.3%, respectively; the reduction with iron was 80%. EMF values measured in incubators were higher than those to which the general population is exposed. The use of ferromagnetic panels significantly reduces the level of EMFs to which neonates and caregivers are exposed.

[Vibration risk during neonatal transport]. / Rischi da vibrazione durante il trasporto neonatale.

AIM: The aim of this paper is to assess the entity of the mechanical vibrations which newborn and medical staff are exposed to and to evaluate the possible risks connected with excessive exposure. METHODS: Vibrations during a simulated emergency ambulance transport were studied. Vibration values with an accelerometer at the level of the incubator's mattress and at passengers' and pilot's seat level were measured. Mean accelerations (awz) and peak accelerations (awpeak), measured using a ponderation filter, according with ISO standard 2631, were considered. RESULTS: Inside the incubator an acceleration mean value of 1.33 (+/-0.13) m/s(2) and peak values of 11.8 (+/-0.1) m/s(2) were found. On passengers' seats the awz findings were 0.55 m/s(2) (+/-0.13) and 0.56 m/s(2) (+/-0.08) while awpeak respectively 4.8 m/s(2) (+/-0.1) and 10.2 m/s(2) (+/-0.1). On pilot's seat a mean acceleration of 0.48 m/s(2) (+/-0.08) and an awpeak value of 4.5 m/s(2) (+/-0.1) were found. CONCLUSION: Peak vibration values which newborns are exposed to (11.8 m/s(2)) are high, when compared with acceleration of gravity (9.8 m/s(2)); this can provoke repeated jerks. Environmental stress can easily alter the stability of an ill newborn and interfere with care manoeuvres. Decreasing vibrations in neonatal transport unit could increase the safety of newborns, reducing the risks which newborns are actually exposed to.

Infrared radiation exposure in traditional glass factories.

This article reports on a general method of evaluating exposure to infrared radiation (IR-A, IR-B, IR-C) from high temperature (T > 1000 degrees C) black body sources, simply by performing measurements with a luxometric and/or near IR detector. The method, which may be applied to any black body source, uses the universality of the Planck formula for the black body spectrum, which allows estimation of the radiated power in any wavelength range by measuring the power radiated in another range. This capability may be very useful when the range of interest is one in which radiometers are expensive and difficult to calibrate, as for the IR-B and IR-C ranges, because a more commonly available luxometer can be used instead. The results of measurements and evaluations in two traditional Italian glass factories are reported and compared with the threshold limit value given by the American Conference of Governmental Industrial Hygienists. Intense exposures in the IR-B and IR-C ranges has been found for some workers, exceeding the limit by a large factor. This exposure must be reduced, as it has been shown by epidemiologic studies that there is indeed a correlation between cataractogenesis and work with fused glass and metals.