Is RF bad for health?
Logically speaking, one cannot say something will never happen. However, carcinogenic effects of such radiation have never been shown in controlled studies.
John
RF can be definitely bad for your health, I know many radio amateurs that carry high power transmitters on their belts, giving them very deep RF burns. Climbing a high power transmitting tower can sterilize you and cause blindness. Fortunately there is not enough energy in RF waves to effect the atoms in your DNA and thus cause cancer. To prove that point look at the rate of brain cancer over the last 30 years, it has not changed by any significant amount, but the use of mobile phones for the same period has increased dramatically.
433 MHz transmitter modules have very low RF output levels and they are not realy dangerous for health unless you have a particular health exceptions.
So far there has never been any scientific proof of other than thermal effects upon human health.
Radio amateurs handing high-power transmitters should be aware that "it can burn" but nobody can get a cancer by operating a 100 W TX. Since 1920s, RF and VHF power has been successfully used to treat joint pain, UHF to treat cancerous tumors by hyperthermy (heating a tumor to 43 deg.C kills it).
In fact, QST has reported that one am was seriously ill when adjusting his 100 W TX at 432 MHz. His problem has nothing to do with cancer- his teeth fillings reacted against gums by a bad irritation and inflammation due to a RF current induced from nearby UHF transmitter.
Nobody is afraid of 500 W at 2.45 GHz in a home microwave oven, but people are very excited of cell-phone dangers emitting 0.5 to 1.5 peak at ~2 GHz. Still, nobody seems to stop talking )
Is it like Russian long range radars (1,000-10,000miles) , with pulse pow up to 10-100MW. Before it turn on, sound loud siren, if you not disappear somewhere you probably lost vision momently.
If seriously, here is to small power.
The only thing that can affect your health when working with a 433 MHz ISM module, is to get mad if is not working properly.
I'm sure you will be OK with 433MHz unless it turns out to be an unlucky number!
RF and health has interested me for a long time, but unless it's obvious like burns is tricky to assess with small population samples.
Genetically we are all different and the exposure to RF can be random, however I do have concerns about mobile phones, that we will need to wait further to know if they are a real risk.
My concerns are not the direct effect of the radiation on DNA, but the indirect effect of heating.
The blood brain barrier keeps lots of nasty things out of our brain, but is very temperature sensitive. Localised heating is being examined as a way of getting drugs through the blood brain barrier for effective 'brain' treatments. You can see where this leads when we put a mobile phone against or head!
Apparently there are also indications non malignant growths are more prevalent in the ear that we put our phone to (from web source so may not be valid. LOL!).
So don't use your phone inside a car where the power out gets turned up!
Do you ever get the vibration sensation in your leg where you tend to keep your phone in your pocket..... and then you find your phone is not there! Google it, lots of people do....
That's my view on RF, but I have no concerns on the 433MHz power levels, or that 'contained' in a microwave oven.
I had a friend who contracted leukemia after being hit by a high power radar beam which also damaged his leg so badly that he walked with a bad limp and a walking stick. FYI It was during National conscription days, he and his mates used to entertain themselves by blowing up jerry cans of petrol on the runway with the high power radar, one day George went out to replace the can and some goon turned the radar on.
Water is bad for your health too. You can drown in it and if you drink to much you die.
The sun is bad for your health, to much will burn your skin and can give you cancer
And so are many things if you get over exposed to it.
Those modules of you are like sunlight trough a spike hole in a box after a sunglass, or like spraing some water on you.
Mobile phones have been with us for a couple of decades now, and users number in billions. A bigger research sample would be hard to contrive. Each time a phone user puts the phone near the ear, the head and body is subject to a field way stronger than from the 25W radiated from the pole at the end of a school playground.
If there was any significant effect, it would have been noticed by now in huge numbers.
Provided one is not carrying any metal, including in tatoos and teeth fillings, humans are apparently able to endure fields beyond 100V/m. 60V/m used to be the limit for US service personell facing radars.
The warning about heating is real. Your tissue can absorb radiation dissipated as a heating effect which can cook flesh, like in a microwave oven, but these fields are not normally encountered unless you stick your hand in said microwave oven. The proteins that make up parts of the eye, like lens and membrane, lacking blood vessels, are supposedly more prone to damage. The advice is still, do not look straight up a waveguide or feed-horn when the signal is on, Do not perch at the focus of an Earth-Station dish with the transmitter on.
RF burns are burns injury from energy. Fire does it too! Good evidence that RF caused a cancer that definitely would not have happened anyway is, so far, just not there. Meantime we continue to use our phones and stroll around in radar fields, in effect accumulating evidence that it does not happen.
I can't say I have any data, but the headlines have 'indicated' a risk
These are a few initial hits returned by Google and the list goes on.....
http://news.bbc.co.uk/1/hi/health/3742120.stm
http://www.dailymail.co.uk/health/ar...in-tumour.html
Also genetic changes apparently can take much longer to appear as with scin cancer can be reult of exposure 30 to 40 years prior to the problem surfacing.
As for the general topicheading, yes there may be risk, but not at the low powers and their typical locations wrt to the body for the type of device being discussed.
Many "professors" are depending on getting money from funding organizations and governments. Easiest way is by doing a valueless research in a spectacular area and after a year write a nice report. These reports have one thing in common. Conclusion is that they have done terrible findings, but more money is needed to proof anything.
No study have yet proved any real danger related to cellphone radiation. No by science accepted proofs have yet been published. Refereed studies at BBC and Dailymail did not say so either. Newspapers writes BS every day. Read the actual report, and check if it is published in any of the well-known scientific papers. A such real finding will get big head-lines in these medias.
The Interphone project that was mentioned in the dailymail link, was a project that did try to add statistical value to all kinds of reports related to cellphone. They did not do any studies by them self. It was a summary of all other available reports.
It was concluded in the Interphone report that adding results from several studies could statistical show that cellphone users had less cancer and less problems with Alzheimer's and similar.
It could be due to a more active life-style then none cellphone users and statistical value in any direction was decided to be too low. With the logic that it is better to be safe then sorrow, in any direction, was use of cellphone set in same poison-category as coffee.
Several of the alarm-reports included in the Interphone report was done by a Swedish professor, Lennart Hardell, who long time ago warned that color TV was more dangerous then B/W TV-sets. Next was computer screens that was even worse as you will drop your teeths, become sterile and the strong fields will cause electrosensitivity. Then have he since many years been concentrated on cellphone studies. Last I heard about him was he working with an investigation of low level, non thermic radiation, resonances and such, at levels even below noise floor, and now says that low level radiation maybe is more dangerous then higher levels of radiation. So wireless headsets is not good at all. If he only can get enough funding will he proof this. DECT is dangerous at any radiation level according to Hardell. No proof yet but...
Anyway, if there is something buried in the statistical material, or if the full cancerogenic effect will take another 10-50 years to show up, do we know from existing studies that this effect is marginal compared to that cellphones already kills a lot of people every year. A part of this is due the fact that cellphone users are less skilled car drivers. Numbers mentioned for Europe says that at least 2000 people are killed every year in traffic accidents related to the use of cellphones, handsfree or not. Badly hurt is ten times as many. US have about same numbers.
It is forbidden in many countries to use phone while driving, but it is also forbidden to be drunk and drive.
This thing with XX numbers of years until full dangerous effect will show up, is something very common in these alarm-reports. It is an alternative to real proof.
"We have no proof yet, but it is on the way."
(from above) Fully agree.
(from a different poster) Disagree.
As per my earlier post this makes me uncertain of the risk....
My real point is we can't say there is 'no risk' whether this is based on the number of mobile users, years of use, ionisation levels, heating effects etc.
If there is a risk it can take much longer to find and be caused by another pathway and a genetic disposition.
Proving a link as you state is often difficult (look at vacinations MMR(what is the latest belief?) or nCJD) and may be in the noise level (hence rubbish small population findings), but if a health effect is found the impact could be large on your expected lifespan (and possibly even worse for the younger generation).
That's all from me, but keep using the TX/RX modules....
Dont worry in both cases you cant avoid contact with RF in any freq ranges.
or if you insist you can get this helmet over eBay as protection:
http://i109.photobucket.com/albums/n...infoilhats.jpg
For sure is not healthy if you are near powerfull RF source or HV power plant cables.
Best regards,
Peter
Just like global warming, oops excuse me, climate change....opinions vary! There is a lot of pseudo science out there. But there are known effects...a few watts of microwave power will heat up your skin surface, so you do not want that to be a continuous 24/7 type of event. Also, there is some evidence that says lower levels of microwaves could cause cataracts in your eyeballs.
The rest, yeah I do not feel great about holding my cell phone next to my head while it is transmitting. If I used it a lot of the time, I would use a Bluetooth headset at a couple of milliwatts instead of a cell phone at .5 watts....simple common sense
I've been using high powered Amateur radio equipment and mobile phones for years and I've never seen anyones ears or mental faculties hurt by them. In fact hgoddb juhlpo bhsyy garubn nayefu kdgeuus ateubgss.
Brian.
not to scare anyone, but there IS interaction with the body. When I used to do a lot of oscillator work, I could actually "hear" the microwaves as I tuned up the oscillator. Was the microwave energy hitting the cochlear and exciting it? Was it hitting my brain and bypassing my ear? Who knows, but I have heard it many different times.
If you just hear the microwaves maybe is not too bad. Dangerous is when you start to see them
This remember me about a quote from an old movie:
-- I see angels, Mickey. They're comin' down for us from heaven. And I see you ridin' a big red horse, and you're driving them horses, whippin' 'em, and the're spitting and frothing all 'long the mouth, and the're coming right at us. And I see the future, and there's no death, 'cause you and I, we're angels... --
I have posted on this before - but regarding being able to "hear microwaves" maybe deserves a little more attention. We are all talking about stuff where the answer is not really known, and managing to ignore a lot of clear evidence on the way.
The exposure of hundreds of millions, maybe billions of mostly city-based folk to very high levels of microwaves from mobile phones, networks, and other sources has been under way for two decades now. Beyond that, we have the direct exposure of both military and civilian folk to extreme radar fields for even longer. Consider the one small example of a officer on a minesweeper - a plastic ship, serving for more than a decade in the side-lobe of the radar above his living area, in a staggeringly high field, apparently to no ill effect. There must be much more like that.
I am aware that pinout disagrees, but to ignore the mass evidence defies credulity. Quoting myself..
Addressing the ways we might "hear" microwaves. No - not directly, but yes - possibly from some secondary effects. Those who have played with Tesla coils know that provided one connects to a large enough area to avoid a RF burn from the hot arc (I gripped a screwdriver), the RF current even at 500kHz is at an AC frequency too high to cause any nerve or other chemical response. The speed of the nervous system is too slow to respond. I felt nothing, even as I watched 100kV corona discharge and the florescent lamp bulb I was holding lit up. I could "hear" the musical note buzz from a tooth filling.
The very loud noise heard in the head when undergoing NMR scanning seems to be at the pulse repetition rate. It is at an audio frequency.
There are folk who have reported hearing "music" and other radio broadcasts, also related to rectification effects from dental or other structures.
Aside from microwave exposure damage from radiant energy at "cooking" levels, by dielectric absorption in the water in the body, it is hard to see how microwaves can mess with the cells. The wavelength is just too long to do that. Being able to "hear" them might be possible by secondary rectification effects. If anyone knows of a direct mechanism to get auditory response from just pure unmodulated RF, then do tell.