How much cesium and strontium is there in our food?

In Kyiv it is a cinch to buy berries and mushrooms from the Chornobyl zone, fish caught in the Prypiat River, and the many other “bounties” of Chornobyl. The Internet newspaper www.24.ua decided to find out how much strontium and cesium there is in locally purchased fish, sausages, milk, and cheese. This was not a difficult task: the city’s Environmental Health Office (SES) does free testing of foods and charges 205 hryvnias to test building materials.

Volodymyr Zhuravliov, an engineer at the radiology department of the Kyiv branch of the SES, recalled some testing that his division had done. “We were testing frankfurters, which turned to have levels of Cesium-137 and Strontium-90 several times higher than normal. Luckily, the frankfurters had been taken off store shelves well before the inspection.”

During the summer public hygiene officers inspect retail outlets at least three times a week. They say they sometimes have to be accompanied by a policeman because the market vendors refuse to allow even a small part of their wares to be tested. Radionuclides are usually found in mushrooms and bilberries, although they also occur in meat.

According to the Web site of www.24.ua , the SES recently tested the carcass of a wild boar shot by hunters. The verdict: it is strictly forbidden to eat this type of meat. Last year the SES and the Department of Veterinary Medicine tested over 576,000 samples. In 19 of them the levels of cesium and strontium were off the chart. Among the tested samples were berries from the village of Malyna and the town of Ovruch in Zhytomyr oblast, the villages of Nemishaievo in Kyiv oblast and Kivertsi in Volyn oblast, as well as mushrooms and game from the Vyshhorod and Polissia districts of Kyiv oblast.

According to Zhuravliov, this year’s tests were all positive. He emphasized, however, that they were random samplings. The radiology engineer knows that there will be items contaminated by radiation among the bounties of the forests, which will be delivered soon to markets and supermarkets. This is why doctors are urging consumers to check what they have bought — especially from street vendors. The SES will do all the tests free of charge. All a shopper has to do is to bring a kilogram or a liter of a product and fill out a formal request to Kyiv’s chief environmental health officer.

Early in the morning the reporters set off to the improvised markets to buy a few things. Doctors had advised them to purchase home-produced meat and milk, riverine fish, beets, radishes, and forest berries and mushrooms because these items are expected to show excessive levels of radioactive isotopes. The first purchase was made near the Pozniaky metro station, where the journalists bought some farm milk. The seller, an old woman, assured us that it was pollution-free. She had brought it from the village of Rozhiv in Makariv raion, 50 kilometers from the capital.

Near the Darnytsia Railway Station the journalists bought a kilo of fresh cheese made in the village of Babyntsi, Borodianka raion, more than 30 kilometers northwest of Kyiv. The seller could not understand why we bought her cheese without tasting it. She became offended and refused to sell it unless we ate a small piece and approved it. We relented and tasted the cheese.

Next, we went to the Lisova metro station, where we bought two sticks of suspiciously inexpensive sausage allegedly from Khmelnytsky oblast — for just 10 hryvnias a half-kilo. At an improvised market near the Lukianivska metro station, we purchased three beets grown in Motyzhyn, a village located 30 km west of Kyiv. Near the Nyvky metro station we bought some radishes from the Brovary area. Since we could not find any street vendors who were selling fresh fish, we had to buy some at a stationary market on Shcherbakov Street. We spent a total of 100 hryvnias on all our purchases and sent them to the municipal SES.

The food testing laboratory is a small room packed with old computers and all kinds of gadgets. The technicians started with the cheese. First they weighed it. The seller had not cheated and had sold exactly one kilo. Then they put a sample on a special tray and inserted it into a gamma- spectrometer, a device for measuring the spectrum of gamma radiation.

The journalists wondered if people could go around a market with a dosimeter and test all the food products on the spot. Zhuravliov laughed and said it would be silly to do that because a dosimeter cannot show faint radioactivity present in food. A lab assistant clicked on a special computer program that deciphers spectrometer signals. Fifty minutes later Zhuravliov showed us the results: the sample only contained the natural radionuclide Potassium-40, which occurs in all foods. The milk did not show any radioactive additives either, although milk is generally the main indicator of an area’s radiation contamination.

“Cows graze in a large area, and if the grass contains Cesium-137 and Strontium-90 in some places, they will definitely show up. If the Rozhiv milk is fine, there will probably be no deviations in the other products from this village,” Zhuravliov said.

No technogenic radionuclides were found in the suspiciously cheap sausage and beets. But as soon as the pieces of pike-perch went into the spectrometer, the computer flashed 16.1 Bq/kg of Cesium-137. Although this dose is nine times lower than the maximum norm, the word “norm” is a relative concept in Ukraine.

According to Zhuravliov, nobody in this country has ever studied the effect of small doses of technogenic radionuclides on humans. Therefore, it has not been ruled out that after you eat this fish, some irreversible processes may start in your body. There is a solution, however: before cooking the fish, you can soak it in vinegar for half an hour. Zhuravliov says that this will help remove some of the dangerous radionuclides.

REFERENCE NOTE

Cesium and strontium are radioactive isotopes. Once they are absorbed by a human body, they impair bone tissue and produce chemical dysfunctions in cells, which later lead to cancer of the blood and bones.