Dr. Cavanaugh:

Hello again. Given the events since the last post… it looks like we are about to have a very radical viewpoint pushed onto the country. So… I’m thinking that whole open-mindedness portion of the previous post (Critical Thinking) is going to get tested in a major way; especially the point regarding not being required to like another person’s point-of-view. Ultimately, I believe this will stamp out our collective social apathy and lead to some really positive change… mainly realizing that people are people and that we are all on the same rock hurtling through space… why not at least try to get along? I just hope there is a country/planet worth inhabiting by the end of the next administration. Which, climate change will be the subject of a future post… but for today, I’d like to address a reader question!

Dear Resident Scientist, 
What I want to know – do phone calls from cell phones pass through our bodies? Do microwaves send waves through our bodies if one stand too close? What things – out there in the world- pass through our bodies without our awareness? What damage, if any, occurs? Cancer? 
Thank you,
Uninformed Resident

Thanks for the awesome question Uninformed Resident (though… I doubt you are uninformed… just differently informed!). When I saw this question… the first thing it made me think of was Johnny Mnemonic. The second is that this same thought occurred to me a few years back, when I started listening to audiobooks to fall asleep (via my phone and sleep headphones). While the official verdict (research science) is still out on this one, it is leaning towards NO (which I agree with). Cell phones transmissions are not carcinogenic (and neither are microwave ovens). Honestly, I am far more concerned about a battery explosion in any of my portable devices (again… a post for another day).

This question is awesome because it touches on so many topics that people know of but probably have not had time to really understand… hence the fear of cell phone ‘signals’ and cancer. My goal here is to help you to gain some understanding of these topics, in order to draw your own informed conclusions. As such… there needs to be some explanation of why & how in order to understand the reasoning. I tried like hell to write this up as a single post, but it was just too damn long. So… today, we’ll talk a bit about cancer because it is the scary part. Then… I’ll hit up the physics to show why you shouldn’t be worried about your cell phone.

But first… Johnny Mnemonic! I have to admit, that I have yet to read the short story this movie is based upon, but William Gibson is a great writer (if you are into the whole cyberpunk genre). Anyways… long story short (warning… spoilers), Keanu Reeves dumps his long term childhood memories to make enough storage space in his wet-wired brain to smuggle a giant hunk of data for a client. Of course… something goes wrong, the data gets stuck in his head, mercenary‑preacher Dolph Lundgren tries to kill him a few times, and finally a dolphin and Ice‑T download the data, saving Reeves from permanent brain damage while also restoring his childhood memories. Happy ending!

So… what the hell does this have to do with cell phone signals? Well, the data turned out to be the cure for a disease called ‘The Black Shakes,’ an insidious plague responsible for countless deaths and widespread fear/turmoil/rioting due to a lack of knowledge regarding its origin and as well as a cure. Henry Rollins (the ER doctor!) reveals that it’s caused by technology… specifically the ‘transmissions and waves’ coming from all the equipment, gear, cybernetic implants, etc. that the world had become dependent upon. Queue the dramatic music. One thing to keep in mind… is that Gibson envisioned this well before cell phones and wireless internet had become ubiquitous. So… I would venture that in our current state, humans are bombarded with more electromagnetic radiation than those inhabiting Johnny’s world. Luckily, nothing remotely similar to the ‘Black Shakes’ has arisen in our world. But, the lack of a fictional disease in the real world isn’t reassuring (or for that matter a valid argument). What about real world fears like cancer? Can the electromagnetic (EM) waves we are steeped in increase the likelihood of cancer? Well… it depends on the wave. (Precisely the sort of answer you expect from a scientist, right!)

But, before we explore the physics, there is an important question to ask… Do you know what cancer is? I’m guessing you have a great deal of knowledge regarding the many causes of cancer but are a little fuzzy as to what happens between too much sun too often and the appearance of an ill-tempered mole on your back. If we take the time to explore this a bit, then we’ll have a solid foundation to evaluate the potential risks of cell phones and microwave ovens. Granted, I’m no expert in oncology/biochemistry/etc, but in my readings, I’ve come to the very broad conclusion that:

Cancer comes down to how your cells talk to one another.

Cells are remarkable. They are tiny factories for manipulating matter at the atomic scale according to the blueprints encoded in DNA – a truly astounding feat, really… go google some of the simulations that researchers have developed to visualize the action occurring at the molecular level. These aren’t just animations… they are simulations relying upon cutting edge physics, chemistry, math, and structural biology to ‘see’ molecular reactions in action.

Back to the topic… cells are tiny nanofactories for building the proteins and enzymes necessary for our bodies to function – an amazing feat all alone – however, there is another layer to their awesomeness. Each cell in your body contains a complete copy of your DNA… thus each one is capable of producing every protein (chemical) present inside your body. However, it would make for a bad day if your liver cells suddenly decided that making liver enzymes was lame and instead started producing keratin (a component of hair and finger nails). These sort of bad days are prevented by a phenomenon known as cell differentiation, which is the process by which cells learn to read the portion of DNA required for their job. This specialization is a result of two factors. First, the surrounding environment: is it warm? is it moist? is it bright? And second, cell signaling… a complex, chemical language cells use to talk to one another.

The first factor is basically cellular natural selection – cells must live in their environment and do their job or they die and probably so do the other cells which are dependent upon them. For example, liver cells live in a warm, dark, moist place. This place is constantly flooded with high concentrations of chemicals (such as sugar, fat, alcohol, etc), and liver cells must do one of the following: process these chemicals for other cells to use; store them for future use; or package them for waste disposal. Skin cells on the other hand must thrive in a bright place while dealing with temperature changes, constant bacterial assault, and cuts/scrapes. You can imagine that liver and skin cells each need a different set of tools (proteins and enzymes) to survive… which naturally affects the portions of your DNA they access.

This differentiation via natural selection is then reinforced by cell signaling. Cells ‘talk’ to one another using concentrations of ions, proteins, enzymes, and hormones. The result is a torrent of information exchanged between adjacent cells as well as throughout your body. This communication is vital, because an individual cell cannot accomplish much on its own… the downside of playing at the molecular level. Each cell is capable of amazing feats in terms of generating complex chemicals/proteins, but the process is low volume. Thus, cells ‘want’ to have friends around because ‘many hands make light work.’ Thus, part of the communication between cells controls the rate at which they divide (reproduce). And, this is where cancer comes into play and your body becomes a Thunderdome. (just think… this all started with EM waves J… I promise we’ll get there!)

In short… cancer cells do not play well with others. They’ve lost their ability to communicate effectively and act selfishly. Cancer cells multiply and use up the surrounding resources (oxygen, energy, etc.) while ignoring their healthy, neighbors’ frantic signals, “Cut it out before everyone dies!” Cancerous cells are essentially invaders to your body. Normally, your immune system identifies an invader (think bacteria/virus/fungus) and wipes it out (another remarkable feat), but cancer cells share enough common traits with healthy cells that your immune system cannot distinguish between them. Thus, they have a free pass to run rampant.

How does this happen? It’s because as remarkable as cells are… they have no capacity for critical thinking. (kinda like a person who drives into a lake on the advice of their in-car navigation). Cells follow the strictest interpretation of the instructions contained in their DNA – no questions asked. If something happens that alters the DNA, such as missing a portion of DNA or a typo (made during DNA replication), then your DNA is considered damaged. The changes are random, and often a cell that has damaged DNA just dies because its instructions tell it to drive off a cliff (in a metabolic sense). This is no problem – the surrounding cells have procedures to handle dead neighbors. However, there is a remote possibility that the DNA damage results in an ill-tempered cell, one that is viable, can multiply (propagating its defective DNA), and no longer plays well with other cells, thus cancer blooms.

Please keep in mind that this is a very generalized view of cancer… there is a reason why we haven’t beat it yet despite all the research funding that has gone into fighting it. But, this overview gives us an idea of what cancer is (a lack of communication between cells) and what causes it (damaged DNA). Which means we are in a much better place to think about carcinogens (things that can damage DNA). The next post(s) will talk a bit more about how DNA gets damaged and how radio waves interact with your body in order to explain why you shouldn’t fear catching cancer from your cell phone (though, I can’t say the same for the Black Shakes… Henry Rollins might have been right!). Thanks for reading!


Dr. Craig Cavanaugh has a PhD in Applied Physical Sciences from the University of North Carolina. His wife, the other Dr. Cavanaugh, has a PhD in Molecular Biology from the University of Colorado. Their sons, Haydn and Riley, the future leaders of the Resistance Against the Machines, read a lot.

His previous posts:  Cool Gus’ Resident Scientist Checks in with his first post

Dr Cavanaugh weighs in on Critical Thinking