There is a serious problem with all to date published epidemiology and human studies because nearly all of them present cell phone radiation exposure as minutes/day of cell phone use.
This is a wrong “measure” of radiation exposure and it causes serious problems for finding effects, it there are any…
Minutes of use of cell phone do not represent well person’s radiation exposure. Two persons, using cell phone in different coverage areas, can be, and certainly are, differently exposed to radiation. In good coverage field, cell phone is emitting much less radiation than the phone being used in poor coverage area.
This means that two persons speaking for the same length of time can receive dramatically different radiation exposures. However, in studies using minutes/day as exposure metrics, these two differently exposed persons are placed in the same exposed group and… analyzed as having “the same” exposure.
This means that if the high exposure causes effect and low exposure causes no effect, the size of the effect in such group will be diminished because of averaging.
This might be the main reason why none of the epidemiological or human volunteer studies was able to show any dose-dependent effect.
If there are any dose-dependent effects they are very well “muffled” by having exposed groups defined as minutes of use of cell phone.
What is “disturbing”, this research was already published as peer-reviewed study and has become a “valid scientific evidence of no effect”… This might be a correct conclusion or a wrong conclusion – we do not know which one because of missing and adequate and reliable radiation exposure data.
Here is as example, one of the “misguided” studies that analyzes exposure as minutes of use and, not surprisingly,… finds no effect…
Pregnancy outcomes after parental cell phone exposure
Valborg Baste1, Gunnhild Oftedal2, Ole Mollerlokken1, Kjell Hansson Mild3 & Bente Elisabeth Moen1, 4
- 1Occupational and environmental medicine, University of Bergen, Bergen, Norway,
- 2Faculty of Technology, Sør-Trøndelag University College (HiST), Trondheim, Norway,
- 3Department of Radiation Sciences, Umeå University, Umeå, Sweden,
- 4Centre for International Health, University of Bergen, Bergen, Norway
Based on the Norwegian Mother and Child Cohort Study (1999-2009), information on maternal cell phone use during pregnancy and paternal cell phone use prior to conception was obtained. The cohort was linked to the Medical Birth Register, Norway to obtain information about all singleton pregnancy. The cohort comprises 100730 singleton births, response rate: 38.7%. There was no association between maternal cell phone use and adverse pregnancy outcomes. Fathers with testis exposure when using cell phones were associated with a borderline increased risks of perinatal mortality and slightly decreased risk of partner experience of preeclampsia during pregnancy compared with no cell phone exposure of head or testis.
The increased use of cell phone has generated new health issues. The exposure to the head has been extensively studied with brain cancer as endpoint but also headache, concentration and behavioural problems has been discussed as possible problems after cell phone use. This concern has led to use of hands-free devices for cell phones to reduce exposure from the phones to the head. Other health issues studied are offspring’s motor or cognitive/language developmental delays among infants at 6 and 18 months of age and behavioural problems in children at age seven and the possible association with mothers’ cell phone use during pregnancy. Some studies have suggested an association between prolonged cell phone use among men and adverse sperm motility, while results concerning other sperm parameters differ among studies. Pregnancy outcome after women’s cell phone use during pregnancy or men’s cell phone use before conception has to our knowledge not been published.
The aim of the present study was to investigate the risk of negative pregnancy outcomes after maternal cell phone exposure during pregnancy and paternal cell phone exposure before conception in a prospective cohort study .
Materials and Methods
Pregnant women were recruited prior to a routine ultrasound examination to the Norwegian Mother and Child Cohort Study that was conducted during the decade 1999 – 2009 . The women answered a questionnaire in gestational week 15 and again around gestational week 30. The questionnaires had identical questions about maternal cell phone use. One question was regarding frequency while the other was regarding duration of calls. The two questions were combined and formed: low, medium and high cell phone exposure.
The expectant father was invited to answer a questionnaire during gestational week 15 (2001 – 2009). Based on the questionnaire two variables were formed to characterize paternal cell phone exposure during the 6 months before conception. Amount of cell phone exposure was based on a combination on frequency and duration of cell phone use grouped in low, medium and high cell phone exposure. The other variable describes what part of the body that was most exposed during a cell phone call: no exposure of head or testis, head exposure and testis exposure.
The response rate was 38.7% and the cohort comprises 100730 singleton births, where 74908 had paternal information.
Pregnancy outcomes were obtained by linkage to the Medical Birth Registry of Norway (MBRN). Reproductive health outcomes studied were congenital malformations, perinatal mortality, low birth weight, preterm birth, borne small for gestational age and preeclampsia during pregnancy.
Log-binomial regression was used to estimate relative risks (RR) and 95% confidence interval (CI) for negative reproductive health outcomes among cell phone exposed with low or no exposure of head or testis as reference group. The analysis regarding maternal exposure was adjusted for (first pregnancy and second or later pregnancy), maternal age and smoking during pregnancy. The analysis regarding paternal exposure was in addition adjusted for paternal age and paternal smoking habits.
Among the pregnant women, 24% had low, 61% had medium and 15% had high exposure during pregnancy. There was no difference in risk of adverse pregnancy outcomes between the cell phone exposure groups; however, when adjusting for potential confounders, the risk of preeclampsia was slightly lower among women with medium and high cell phone exposure compared to low exposure.
Among the fathers, cell phone exposure was low for 27%, medium for 52% and high for 21%. While 28% had no exposure of head or testis, 66% reported head exposure and 6% testis exposure during cell phone calls. Fathers with testis exposure when using cell phones were associated with a borderline increased risks of perinatal mortality and slightly decreased risk of partner experience of preeclampsia during pregnancy compared with no cell phone exposure of head or testis. None of the other pregnancy outcomes were associated with paternal cell phone exposure.
We found no association between maternal prenatal or paternal preconceptional cell phone exposure and any of the studied pregnancy outcomes. The only risk estimate suggesting a potential increased risk was not consistent with the other findings.
 Baste V, Oftedal G, Møllerløkken OJ, Hansson Mild K, Moen BE. Prospective study of pregnancy outcome after maternal and paternal cell phone exposure, The Norwegian Mother and Child Cohort Study. Accepted for publication in Epidemiology.
 Magnus P, Irgens LM, Haug K, Nystad W, Skjaerven R, Stoltenberg C and the MoBa Study Group. Cohort profile: The Norwegian Mother and Child Cohort Study (MoBa). Int J Epidemiol 2006; 35:1146-50.
Thanks Tom. This time I fully agree with you…
This harks back to your December 18, 2010 blog entitled “A job worth doing is a job worth doing well;” and seems so obvious! Using a crude proxy instead of gathering actual exposure data may save a lot of time and money. But, it cannot give us accurate and reliable exposure assessment/dosimetry. And without this, it is impossible to reach reliable conclusions.
It is pointless to continue employing unreliable methods and expecting reliable results. It isn’t going to happen! And this fatal flaw affects all studies equally; whether they are negative or positive.
The existing practice is analogous to estimating a person’s food consumption by guessing how often they visit – and how much time they spend – at the dinner table!