Habits of cell phone usage and sperm quality – does it warrant attention?
Ariel Zilberlicht, Zofnat Wiener-Megnazi, Yulia Sheinfeld, Bronislava Grach, Shirly Lahav-Baratz, Martha Dirnfeld. Habits of cell phone usage and sperm quality – does it warrant attention? Reproductive BioMedicine Online, Available online 18 June 2015.
This study investigates an association between characteristics of cell phone usage and semen quality. Questionnaires accessing demographic data and characteristics of cell phone usage were completed by 106 men referred for semen analysis. Results were analysed according to WHO 2010 criteria.
Talking for ≥1 h/day and during device charging were associated with higher rates of abnormal semen concentration (60.9% versus 35.7%, P < 0.04 and 66.7% versus 35.6%, P < 0.02, respectively). Among men who reported holding their phones ≤50 cm from the groin, a non-significantly higher rate of abnormal sperm concentration was found (47.1% versus 11.1%). Multivariate analysis revealed that talking while charging the device and smoking were risk factors for abnormal sperm concentration (OR = 4.13 [95% CI 1.28–13.3], P < 0.018 and OR = 3.04 [95% CI 1.14–8.13], P < 0.027, respectively).
Our findings suggest that certain aspects of cell phone usage may bear adverse effects on sperm concentration. Investigation using large-scale studies is thus needed.
In the present study it was found that certain characteristics of cell phone usage are highly associated with low sperm concentration. Several studies have reported observational data on exposure to cell phone radiation and sperm parameters. The main strength of the current study is the detailed information on many characteristics of cell phone usage.
Talking on a cell phone for more than one hour per day was associated with an elevated rate of abnormal sperm concentration. This concurs with the results of Agarwal et al., who reported that talking for a duration of more than 4 h/day on a cell phone was associated with a lower sperm count, as well as a lower number of viable sperm, motility and morphology ( Agarwal et al., 2008). Similarly, longer daily transmission time on cell phones was associated with a lower proportion of rapid progressive motile sperm ( Fejes et al., 2005).
The lack of association found between cell phone usage and sperm motility, a finding that has been demonstrated in previous studies, may be due to differences in criteria for sperm motility between WHO 1999 and 2010 manuals for reference values for semen parameters.
The participants in this study, who reported talking on their phones while the device was being charged, were more likely to have abnormal semen concentration. To our knowledge, this aspect of cell phone use has not been previously addressed. During charging of cell phones, two changes occur: (i) the external power source by itself emits energy; and (ii) due to the continuous supply of energy from the external source, the device transmits at a higher power, without the need for energy saving, in contrast to the usual talking mode.
Participants who constantly carry the device at a distance ≤50 cm from the groin were found to have a higher rate of abnormal sperm concentration. Although the association did not reach statistical significance, it appears that sperm parameters may be affected, even during a stand-by mode (when RF-EMR is emitted from the device for short durations). Similarly, Kilgallon and Simmons reported that men who carried a cell phone in a hip pocket or on their belts had 11% fewer motile sperm than men who kept a phone elsewhere on their body (Kilgallon and Simmons, 2005). Another study showed that men who carried a cell phone on their belt ≥6 h/day for 5 days, had a 19% drop in highly motile sperm from their previous concentrations (Davoudi et al., 2002).
A multivariate logistic regression analysis revealed a strong independent effect of two variables on the risk for abnormal sperm concentration: talking while the device is being charged and smoking.
A number of mechanisms may explain these findings. For one, emission of RF-EMR has both thermal and non-thermal effects. However; there is no consensus as to which effects predominate (Dasdag et al., 2003; Weisbrot et al., 2003). RF-EMR emitted by cell phones can induce DNA damage to spermatozoa, may affect sperm motility and may correlate with sperm chromatin damage (Davoudi et al, 2002 and Giwercman et al, 2003). Studies of military personnel who self-reported exposure to RF-EMR showed an elevated risk for infertility, compared with those who did not (Baste et al., 2008). Similar findings were described recently (Gorpinchenko et al., 2014). This mechanism may be explained in the light of long-term use of cell phones, as an RF-EMR-mediated reduction in spermatogenesis and thus lower sperm concentration. In-vitro studies on mice suggested that Leydig cells are among the most susceptible cells to RF-EMR, a mechanism that may also explain the effect on spermatogenesis (Wang et al., 2003). RF-EMR may cause an increased body temperature, particularly in the groin, and thus cause disruption of spermatogenesis (Jung, Schill, 2000 and Kandeel, Swerdloff, 1988). RF-EMR waves emitted from cell phones may lead to oxidative stress in human sperm (Agarwal et al, 2009 and Erogul et al, 2006), which causes DNA fragmentation in somatic cells (Sun et al., 1997).The latter may serve as a common postulated pathway to the above-mentioned mechanisms.
In conclusion, the findings of this study suggest that a few small changes in cell phone usage, such as avoidance of talking while it is being charged, reducing the total time of conversations and keeping the device away from the groin may be highly beneficial for men seeking fertility. From a practical point of view, men who seek fertility are advised to turn off their devices while charging or, if not possible, to keep the device at least 50 cm from the groin during daily activities and while sleeping. Users are advised to carry the device a distance from the groin, for example in the shirt pocket, and to talk using earphones or to use a speaker whenever possible. A large scale study is needed to assess these and other possible effects of cell phone usage on sperm quality.
Also see: Adams JA, Galloway TS, Mondal D, Esteves SC, Mathews M. Effect of mobile telephones on sperm quality: A systematic review and meta-analysis. Environment International. 70:106-112. September 2014.http://www.saferemr.com/2014/
Joel M. Moskowitz, Ph.D., Director
Center for Family and Community Health
School of Public Health
University of California, Berkeley
Electromagnetic Radiation Safety
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