ARKHANGELSK, Russia — From the promenade at the water’s edge in the city of Arkhangelsk, a view opens of the broad, fast-flowing Northern Dvina River and a smudge of greenery on the far bank.
About 40 miles in that direction, a still mysterious nuclear accident last week released radiation, killed at least seven people and tripped radiation meters in two cities, including Arkhangelsk.
Yet there they were, Ilya and Yelena Ivanov, pushing a baby stroller on the embankment along with dozens of other new parents, taking in a cool, moist breeze blowing off the water.
“It is worth worrying about,” Yelena said of the radiation release. But the baby, 1-year-old Marina, needed air and besides, she said, nobody had warned against going outside.
Ilya held a different view: That if there really was something to worry about, people would know.
“They cannot hide anything,” he said of the government, despite the official silence on details of the incident on Aug. 8 that apparently involved the explosion of an experimental, nuclear-propelled missile known in the West as the “Skyfall.”
“We aren’t living in the 1980s,” Ilya said. “We are a contemporary society.”
In fact, experts on nuclear safety say, there is no means to settle the parents’ debate. Scant public comments from the Russian authorities offer too few technical details to assess safety for communities near the explosion. Without knowing the radioactive substances used in the missile, the nature of the fallout also remains unclear, experts say.
Arkhangelsk, a port with a rich history stretching back to medieval Russia, this week became a city of home remedies for radiation.
On Friday, the Ministry of Emergency Situations, a Russian agency responsible for civil defense, issued a daily update on the Arkhangelsk region saying that “the radiation, chemical and bacteriological situation is normal.”
And it offered the advice to “wash your hands with soap more often,” though it was unclear whether this related to radiation or just good hygiene.
The cloak of secrecy around the explosion, part of stepped-up testing of new delivery systems for nuclear weapons by Russia and the United States in what some see as a renewed arms race, has left residents on edge.
A flurry of misinformation and misdirection in Russian state media has not helped. On the day of the accident, the Russian military released a statement carried by Tass, a state news agency, saying a rocket engine had exploded and radiation levels were normal. But in an online post that was subsequently removed, city authorities in Severodvinsk, about 25 miles away from the site, said radiation briefly spiked.
Two days later, Rosatom, the Russian nuclear energy company, issued a vague statement saying an accident involving radioactive isotopes had killed five employees.
Bruno Chareyron, laboratory director at CRIIRAD, a French nongovernmental group that monitors radiation risks, said in a telephone interview that any airborne radioactive materials had most likely settled into the water or onto soil or vegetation.
If what exploded was a small nuclear reactor fueled by plutonium or uranium, he said, it would release a range of contaminants including radioactive iodine that poses a risk of thyroid cancer. The device, however, may have used other fuels.
“Scientifically, it is impossible to answer the question of risk,” Mr. Chareyron said. In the meantime, he said, “don’t eat fresh vegetables,” a warning not heard from Russian officials.
On Thursday, Norway’s radiation and nuclear safety authority said it had detected tiny amounts of radioactive iodine in northern Norway.
But such traces waft across from Russia half a dozen times a year, from old nuclear tests or leaks, rendering it impossible to determine the origin, the agency said.
Russian officials have not said whether the explosion released iodine isotopes, which might tip their hand on the type of fuel used in the novel missile design, even as residents take medication against iodine contamination.
Tatyana A. Kozyreva, a saleswoman at an Arkhangelsk drugstore, has been dispensing her own advice on taking supplements of nonradioactive iodine. “Nobody told us anything,” she said. “The bosses are all on vacation.”
She said she counsels customers to take “40 drops of iodine in a glass of water” daily against radiation.
With nary a word of advice from government doctors, independent scientists have stepped in.
One is a professor of mathematics, Aleksandr Yufryakov, who posts advice next to an illustration of a glowing mushroom cloud. “Better be active today than radioactive tomorrow,” he recommends.
He posts analyses of wind currents on the day of the accident, and advises against eating berries, mushrooms and fish, or drinking milk from local cows.
On Friday, the Russian meteorological agency reported in a statement that “it is supposed” that the spike in radiation on Aug. 8 in the city of Severodvinsk resulted from “the passage of a cloud of radioactive inert gasses.” The agency said it quickly dispersed.
But a radioactive cloud might contain a mix of contaminants and settle unpredictably in hot spots, Mr. Yufryakov said. “Imagine how unpleasant it would be to find your garden was a hot spot,” he said.
“The government is silent and what has been said is contradictory, meaning it is a lie,” Mr. Yufryakov added. “This information vacuum is creating worry and even panic.”
Okasana Vladyka, a lawyer, said she was angry but not surprised by the government’s silence.
“They cannot say anything because that would mean admitting a mistake,” she said. “And then they would have to pay compensation.”
At the Arkhangelsk Regional Clinical Hospital, where those injured in the incident were first treated, doctors and nurses were not warned of radiation risks, said a nurse who offered only her first name, Viktoria, out of concern she said might face retribution for speaking publicly.
Later, doctors found their scrubs were causing radiation meters to click. Those who treated the injured were subsequently evacuated to Moscow for treatment.
“They didn’t tell us anything,” Viktoria said. “Then they told us, ‘we will wash the walls and then everything will be all right.’”
For the authorities who may have been wary of setting off panic, there was never going to be an easy way to sugarcoat news that an experimental nuclear weapon had exploded near population centers.
And in at least one instance, officials appear to have risked breaching secrecy to safeguard children. Lyudmila Kongratyeva, 32, a secretary in Severodvinsk, heard rumors of radiation on the morning of the incident. “My maternal instinct set in and I immediately called the kindergarten” attended by her 4-year-old son, she said.
But somebody with knowledge of the nuclear accident, perhaps in the military or civil defense agency, had beat her to it. “They said ‘mother, don’t worry, we got a warning and closed all the windows.’”