Chernobyl fallout in Mushrooms!

On the 26th of April, 1986, reactor number 4 at Chernobyl Nuclear Power Plant exploded. As a result, a large amount of radioactive isotopes was released into the environment contaminating most of eastern Europe.

Today, 35 years later, most radioactive isotopes with short half-life have decayed with only 6 isotopes remaining in significant amounts from which Caesium 137 and Strontium 90 make the top of the list.

Recently, my good friend was in Belarus and during his trip, he collected some local mushrooms.

Why do I bring this up? Because mushrooms, particularly bay boletes, accumulate heavy metals. This means that if they grew in an area contaminated by radioactive fallout then there should be a detectible amount of Caesium 137 in them.

Belarusian mushrooms

When measured with Ludlum Model 3 Survey Meter with a Johnson Pancake probe, the reading was around 150CPM which is over 3x the normal background radiation.

In order to make sure that the activity coming from these mushrooms is caused by Chernobyl fallout, I did a Gamma spectroscopy using RAYSID gamma spectrometer.

After a few minutes, a narrow peak started to form at 662keV, which is very characteristic for Caesium 137 which means that these mushrooms are contaminated by nuclear fallout from Chernobyl.

Gamma spectroscopy of the radioactive mushrooms (without lead castle)

Since I am not an expert, I can not tell you whether or not eating such mushrooms is safe but if you ask me, I do prefer non-radioactive ones!

Is the Gamma-Scout Geiger counter any good?

Gamma-Scout is an iconic Geiger counter but is it any good? Let’s find out!

Before I start, I must say that the unit that I got is not stock. It has a new battery and the GM tube was swapped for Philips ZP1400 since the original Ludlum LND712 was broken. Lastly, I have also added a metal mesh in front of the GM tube for some additional protection when measuring alpha radiation.

The version I got is the Standard model which retails for around 380 euros. Gamma-Scout offer three other models. Alert model which has an audible clicking sound and a settable alarm, a rechargeable model that has a rechargeable battery and an Online model which allows user to connect the Geiger counter to PC wirelessly.

Despite the fact, the GM tube was not original, the results I got were fairly similar to my other Geiger counters which meant that Philips ZP1400 is a very good alternative to the LND712.

Gamma-Scout next to Terra-P

One small design issue that I noticed with the Gamma-Scout is that the GM tube is slightly pushed back into the meter. This means that detecting alpha particles will be more difficult since they have a very small range.

What I really like about this meter is that it can detect alpha, beta, gamma radiation and it shows readings in dose units as well as raw activity (CPS).

Unlike most electronic devices, Gamma-Scout has no on/off button. It remains always turned on until the battery dies. Luckily, this unit is designed to run for over 10 years without the battery running out, and if it does, Gamma-Scout recommends sending the unit back to them for battery replacement and calibration but in my experience, it is fairly easy to replace the battery by your self if you know how to solder.

Unfortunately, this meter also has some downsides. There are some quality control problems including the radioactive logo being distorted and the upper and lower body parts not fitting perfectly even with screws tighten. These are small issues but they should not exist on a Geiger counter that cost almost 400 euros!

Berlin Zehlendorf 10/02/2021

What bothers me the most is that the standard model does NOT come with a speaker! In my opinion, a clicking sound should be a standard feature on EVERY modern, handheld Geiger counter. Even my cheap 30 euro DIY Geiger counter has a tiny speaker built-in. If you want audible clicking sound then you need to buy a more expensive Alert model.

Overall, I think that Gamma-Scout is a-OK Geiger-counter but it feels outdated and I find it to be overpriced. That is why I would not recommend the Gamma-Scout standard model and I would suggest looking at other meters from the competition. A good alternative that comes to my mind would be Radiascan 701.