Where’s Your Phone? A Survey of Where Women Aged 15-40 Carry Their Smartphone

vrijdag, 13 januari 2017 - Categorie: Onderzoeken

Bron: journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0167996

Where’s Your Phone? A Survey of Where Women Aged 15-40 Carry Their Smartphone and Related Risk Perception: A Survey and Pilot Study

Published: January 6, 2017http://dx.doi.org/10.1371/journal.pone.0167996
Mary Redmayne
School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia


Smartphones are now owned by most young adults in many countries. Installed applications regularly update while the phone is in standby. If it is kept near the body, this can lead to considerably higher exposure to radiofrequency electromagnetic radiation than occurred without internet access. Very little is known about current smartphone carrying habits of young women. This survey used an online questionnaire to ask about smartphone location under several circumstances to inform the power calculation for a women’s health study. They were also asked about risk perceptions. Data was analysed using Pearson chi square. Three age categories were made: 15–20, 21–30, 31–40. Smartphones were generally kept on standby (96% by day, 83% at night). Of all participants, in the last week the most common locations of the phone when not in use or during passive use was off-body (86%), in the hand (58%), a skirt/trouser pocket (57%), or against the breast (15%). Pocket and near-the-breast storage were significant by age (χ215.04, p = 0.001 and χ210.96, p = 0.04, respectively), both positively influenced by the youngest group. The same influence lay in the association between holding the phone (χ211.082, p = 0.004) and pocket-storage (χ219.971, p<0.001) during passive use. For calls, 36.5% solely used the phone against the head. More than half kept the phone 20–50 cms from their head at night (53%), while 13% kept it closer than 20 cms. Many (36%) thought RF-EMR exposure was related to health problems while 16% did not. There was no relationship between thinking RF-EMR exposure causes health problems in general and carrying the phone against the upper or lower body (p = 0.69 and p = 0.212, respectively). However, calls with the phone against the head were positively related to perception of health risk (χ2 6.695, p = 0.035). Our findings can be used in the power calculation for a case-control study.

For the complete article see the link above. Here we add the discussion and the conclusions:


Many smartphone applications use pull or polling technology, and long polling, to keep updated with the latest available material, be it a social networking message, email, GPS position, or an advertisement about a clothing sale 18 and apps can update every 30 seconds. This means that for those who have several active applications such as social networks, messaging, marketing, GPS, and news, the phone is likely to transmit much of the time it is in standby. Each time, all the phone’s functions and apps are activated, not only the relevant app. Participants’ phones were usually left in standby.

The most common place for the phone when not in use was off the body, however, a large majority of women in our study regularly carried the phone in a trouser or skirt pocket (57% in the last week and almost three quarters had done so) and very similar numbers regularly carried it in their hand.

A surprisingly large proportion of women had carried their phone close to or against the breast recently (15%), including a third of the ≤ 20 age group. A quarter of women had ever done so. This is the necessary information for planning the proposed breast cancer study and would provide the same assistance for the study of a variety of other endpoints.

Even in standby and flight mode, the Central Processing Unit continues functioning. Induced electrical coupling occurs with close proximity for exposures at 450 MHz and lower 19. This frequency or lower is used in iPhones by the graphics processing unit or central processing unit. These frequencies penetrate the body further than the higher carrier frequencies used for calls and internet.

There is some evidence that perception of risk may have impacted on behaviour to some extent such as whether or not to use the phone against the head when making calls, since those who were concerned about it were significantly less likely to use it that way.

The picture was more complex though for perception of risk for specific carrying locations versus behaviour versus perception of the risk of specific diseases. For instance, there was an association between perceived risk of carrying a phone in the bra and actually carrying it there, but there was a dissociation between that action and perceived risk of specific disease outcomes.

Concern over effects of RF-EMR on digestion and the immune system were the only specific diseases with a clear statistically significant relationship driven by those who chose not to keep their phone in a pocket. In the sensitivity analysis, other significant associations were found for nervous system complaints, thinking/memory/concentration, and emotional/mental health (anxiety; mood; depression). These symptoms are typical of those with electrohypersenstivity. However, other typical electrohypersensitivity symptoms were not statistically associated with phone storage against the breast or in a lower pocket (complaints such as heart function, vision, and motor problems such as aches, pains and weakness), so this should be interpreted with caution.

Interestingly, there seemed to be some dissociation between the three health problems that a majority were concerned about (sleep, cancer, headaches/dizziness) (Fig 9) and behaviour in terms of whether the phone was stored in either a pocket or by the breast (Tables 3 and S1).

We asked participants whether they attributed any health problems they experienced to use of a mobile phone. Although the survey focus was RF-EMR, this does not establish what aspect of the use they believe caused the problems. There are several possible explanations such as unusual posture or prolonged skin contact with the phone surface. Some symptoms may result from conviction that RF-EMR exposure is going to cause problems. Research has demonstrated this sometimes occurs although this explanation does not fit with the typically reported order of symptom onset first followed later by causal attribution 20. Exposure to the phone’s RF-EMR emissions cannot be discounted as a cause and common, measurable changes in bio-chemistry have been demonstrated in many people reporting electrohypersensitivity 16, 21.

This study provides a considerable amount of new information on which parts of the body are most exposed to RF-EMR when smartphones are not being used, as well as during passive and active use. It would have been more helpful had we asked for information about storage location when people are outside separately from when in the car. Knowing duration of exposure in any one location would also be of help.

The ethical choice not to pursue further risk questions with those who did not perceive any risk impacted somewhat on analysis of possible links between perception of risk and behaviour. However, a useful amount of new information was gained using the one risk question (Q14) that all participants were asked. Future studies on smartphone storage could usefully include the use of an application in participants’ smartphones to measure actual use and/or exposure providing they agree not to lend their phone (or borrow others) during an agreed study period.


The information collected in this study can be used in the power calculation for the number of people needed for a case-control study. Several such studies may be called for as so many people carry smartphones against the body where they continue to transmit. More than three quarters of participants had carried their phone in a skirt or trouser pocket, which places the phone adjacent to the skin of the lower abdomen or buttock sitting over or near the colon and near reproductive organs, and a quarter of them had carried it tucked into clothing against the breast. Overall, there was not a perception of risk from exposure to RF-EMFs generally, although when specific types of illness and/or specific on-body storage locations were analysed, it was apparent there was a significant concern about carrying and using a smartphone against the body/head (although this behaviour was common). There was also a significant relationship between digestion and the immune system, and carrying the phone in a lower pocket. The sensitivity analysis indicated concern about keeping the phone in a pocket and several typical electrohypersensitivity symptoms.

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