DIY CROWDSOURCED RADIATION TESTING

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SAFECAST
http://english.aljazeera.net/news/asia-pacific/2011/08/2011810142915166342.html
Citizen group tracks down Japan’s radiation
Amid contradictory government statistics, a volunteer group has recorded 500,000 radiation points across the country.
by Dahr Jamail / 10 Aug 2011

The aftermath of the Fukushima Daiichi nuclear crisis has been marked by an outcry in Japan over radiation leaks, contaminated food and a government unable to put the public’s fears to rest. Perhaps the most worrying aspect of the meltdown that resulted from March’s earthquake–triggered disaster, activists and citizens have said, is the uncertainty that has ensued. In the months since the catastrophe, the Japanese government, its nuclear watchdogs and Tokyo Electric Power Company (TEPCO), have provided differing, confusing, and at times contradictory, information on critical health issues. Fed up with indefinite data, a group of 50 volunteers decided to take matters, and Geiger counters, into their own hands. In April, an independent network of like-minded individuals in the Japan and United States banded together to form Safecast and began an ongoing crusade to record and publish accurate radiation levels around Japan. The group handed out mobile radiation detectors and uploaded the readings to the internet to map out exposure levels.  Sean Bonner, director of Safecast, told Al Jazeera that volunteers have so far logged more than 500,000 radiation data points across Japan.  He said the group is the only organisation he knows that is tracking radiation on a local level. The findings, Bonner added, have been shocking. “People keep asking how we are doing it, when the government isn’t,” he said.

Lack of information
Dr Yuko Yanagisawa, a 51-year-old physician at Funabashi Futawa Hospital in Chiba Prefecture, feels the government’s response to health concerns has been grossly inadequate. In the area where Yanagisawa lives and works, approximately 200 km from Fukushima, unhealthy radiation levels have been recorded. Even so, she said the only information the government has released was to raise the acceptable radiation exposure limit for children from one millisieverts (mSv) of radioactivity a year to 20. “This has caused controversy, from the medical point of view,” Yanagisawa told Al Jazeera. “This is certainly an issue that involves both personal internal exposures as well as low-dose exposures.” From the start, the government’s track record on public health announcements has been poor. As early radiation readings from the disaster site emerged, Japan’s then-Minister for Internal Affairs, Haraguchi Kazuhiro, alleged that monitoring station data was actually three decimal places greater than the numbers released to the public. In late March, the Japanese Nuclear Safety Commission conducted a survey that found an estimated 45 per cent of children in the Fukushima region had experienced thyroid exposure to radiation. But the commission has not carried out any surveys since.


Health specialists say the commission fears a negative public reaction to children’s exposure to radiation from the crippled Fukushima plant.

Contaminated food fears
Recent disclosures from government agencies and TEPCO, the operator of the Fukushima plant, suggest that public information has hardly improved. Earlier this month, TEPCO said it detected 10,000 mSv of radioactivity at the heavily damaged plant. A dose this high would be fatal to humans, and was 250 per cent more than the previous high levels at the plant in March soon after the disaster. Authorities have also been vague about the extent of the radiation, and how the potential spread may be affecting vital food crops and livestock. Jyunichi Tokuyama, a specialist with the Iwate Prefecture Agricultural and Fisheries Department, said he was shocked to find radioactive hot spots in his prefecture, more than 300km from the stricken Fukushima nuclear site. “The biggest cause of this contamination is the rice straw being fed to the cows, which was highly radioactive,” Tokuyama told Al Jazeera. On August 1, Iwate became Japan’s forth prefecture to suspend all of its beef exports due to cesium contamination. Neighbouring governments have announced plans to test Japan’s agricultural exports for radioactive cesium after concerns over soil contamination.

‘Not getting the data’
Despite the alarm inside Japan and abroad, specific information about radiation levels and its range are still mostly unavailable. This lack of information is what Safecast is trying to overcome. “We spoke with a woman in Japan on Saturday who said since March she’s been calling her local offices, and the federal government, just trying to get data, and she’s not been able to get a single reading close to her house,” Bonner said. “Part of that is that the information is just not there, the government doesn’t have it. I don’t think they are necessarily withholding, but I think they are just not getting the data.” Bonner said he was disturbed by the readings he took last weekend nearly 28km outside the Fukushima site. The Japanese government maintains a mandatory evacuation zone around the plant that extends to 20km, the next 10km is the voluntary evacuation zone. People who live there are not given any financial compensation by the government if they choose to evacuate. “Sunday [August 7], we found ground contamination of 20,000 cpm,” said Bonner, referring to counts per minute, a method he believes is more accurate in analysing radiation than measuring mSv. “It was about 28km from the plant. There were police officers there standing around all day making sure nobody went into the mandatory evacuation zone, wearing no protective clothing. They said they didn’t know what the readings were, they were just told to be there.” Bonner plans to return monthly and continue with the project “indefinitely”. “Getting into this has showed us there is a lack of data everywhere,” he said. “This week I’m going to start mapping radiation data in California, and we’re going to start getting devices to people around the US and Europe. We’re going to set up fixed sensors and we’re making a device that we’ll sell to the public. We’re hoping to continue to get lots of data from lots of sources.”

Global debate
The Japanese government does not consider non-government readings to be authentic, and has urged the public to only rely on government data on radiation. Bonner said: “Getting into this has showed us there is a lack of data everywhere. We’re going to start getting devices to people around the US and Europe. We’re going to set up fixed sensors and we’re making a device that we’ll sell to the public. We’re hoping to continue to get lots of data from lots of sources.” Bonner’s ambitions appear timely against the backdrop of a revitalised global debate on the dangers of nuclear energy, especially in Japan. Prime Minister Naoto Kan recently pledged to lower Japan’s reliance on nuclear power due to the consequences of the Fukushima crisis. He and other officials have admitted to deep concerns about radiation-induced health risks. “Japan will reduce its level of reliance on nuclear power generation with the aim of becoming a society that is not dependent on nuclear power,” Kan said last week in Hiroshima in a speech to mark the 66th anniversary of the US atomic bombing of the city.

New Visualizations

http://maps.safecast.org/drives
http://blog.safecast.org/2011/08/new-visualizations/#more-1273

One of our goals at Safecast, in addition to collecting radiation data, is putting that data into a format that is helpful and useful. If you’ve been following our work for the last few months you’ve seen the map we launched with on day one progress through several evolutions including being split out into several specific purpose versions. We’ve just launched a new revision to these and now have a maps specific URL we’re we’ll keep all the mapping visualizations we’re producing. Please take a look atmaps.safecast.org.

What you’ll see there:
Safecast Map: This depicts over 500,000 radiation data points collected by the Safecast team throughout Japan. For each square, numerous geiger readings have been collected and color-coded. This is our main map and the one we’ll be tweaking and improving on a very regular basis.

Full Data Set Map: While the Safecast Map simplifies the readings into a general grid, the full data set map actually shows you each and every point we’ve collected. It’s very dense, but if you want to drill in this is where you can do it. This collected data set will be available for download in the near future.

Drive Maps: Both of the above maps are based on data we’ve collected driving around with out bGeigie sensors. If you want to see an individual drive on it’s own check out the Drive Maps, you can also download a CSV file for each drive to play with the data yourself.

Fixed Sensor Network: We’ve been working with our partners at Keio University’s Scanning The Earth project to build a network of fixed sensors, and this maps shows the data coming in from those devices we’ve installed out in the field. STE has a great historical visualization of these points, and Yahoo! Japan has just release their own map using the data we’re providing from these devices.

Aggregate Map: We also still have the original Aggregate Map showing all the data we’re scraping from other sources.

http://blog.safecast.org/2011/04/first-safecast/

While these are our newest maps, they are by no means our final versions and we’ll continue to edit and improve these as our work continues – that said we think these are a step forward from our last versions, and hope our next step will be an improvement to these. We know there are some missing legends and a little better explanation of what the colors/points mean and hope to have that up soon, but if you have any other feedback, requests, comments, concerns, etc please let us know.

Our new set up includes two geiger counters (one mounted outside the car, one handheld inside which can also be used if stopped and walking around), a laptop, a GPS module, mobile wifi hotspot and some weather proof casings. Once installed on a car this lets us track a great deal of info and upload it immediately. This is what we’re collecting data wise:

  1. • year-month-day
  2. • hour:minute:second
  3. • CPM (counts-per-minute)*
  4. • Latitude: ddmm.mmmm, dd is integer in degree, mm.mmmm is decimal in
    minute. We can divide mm.mmmm by 60 to get degrees.
  5. • N/S (north/south indicator)
  6. • Longitude: dddmm.mmmm, ddd is integer in degree, mm.mmmm is decimal
    in minute. We can divide mm.mmmm by 60 to get degrees.
  7. • E/W (east/west indicator)
  8. • GPS Quality indicator
  9. • Number of satellites available
  10. • Precision in metres
  11. • Altitude in metres
  12. • GPS Device name
  13. • Measurement type

*The use of CPM is noteworthy since most of the reports are currently using µSv/hr. There is currently a great deal of discussion about which measurement is better or more accurate as µSv/hr doesn’t specify isotopes and can vary based on what is being measured. In our case however the International Medcom Inspector Alert geiger counters that we are using displays both, but output via the connector is CPM. We’re taking note of both and using µSv/hr in discussion but will continue to look into this and evaluate which is a better unit of measurement for these purposes. In this case dividing CPM by 350 gives us µSv/hr.

Our plan has been to install this system into a car and then drive north into Fukushima to elementary, junior high and high schools outside of the evacuation zone and try to get some readings there and along the way. Assuming that worked we’d replicate this set up in several cars so we can cover ground more quickly. For this run we several more hand held counters just to double check the readings and set ups.

#bGeigie -first bento boxed shaped automated geotagging Geiger counter system

On Saturday, April 23rd we gave this the first field test. Japan team members Mauricio, Pieter, Robin and Steve met up at Tokyo Hackerspace first thing in the morning, hooked things up, tested them and hit the road. The Fukushima newspaper printed a radiation map showing readings around the evacuation zone which was you can see had quite a bit of variance so we hoped to get more data to cross reference with this.

#fukushima newspaper Radiation map showing 20km zone and radiation levels. Notice variance on the edges of the zone.

Additionally part of our mission is to distribute equipment to people who can continue to take readings on their own after we’ve left and have them continue to upload data to our site so we will have historical data as well. I’m happy to happy to announce that we did just that with this trip to Koriyama and were able to leave two sensor devices and an iPhone (for uploading images and data to our servers) with a team of volunteers there.

Met volunteers for #safecast.org in koriyama and handed a Geiger counter and geotagging iPhone to start data reporting

As for the actual data we recorded, that was very interesting. We’re in the process of checking the logs (removing duplicate entries and things) and will have it uploaded toour map and pachube shortly so every point we recorded will be visible and available for evaluation by outside parties. Here is photo documentation of some of the readings we took with the handheld devices. All in all we drove for 6.5 hours and measured close to 5000 locations. We measured at the gate of 5 schools in Koriyama.

We took one reading that was considerably higher than all the others:

This was the highest we reading we took, but we consistently measured 20-30µSv/hr on pavements, etc. and 5-10µSv/hr for soil (typically 5-6 for soil) For air measurement, we have very consitent data as it is measured across the entire ride. In Koriyama it was in the range of 1.2 to 2µSv/hr. We had 3 Medcom devices giving consitently the same value and a Gamma Scout that gave same readings for air. This multiple redundancy was to ensure we didn’t have malfunctioning equipment or a calibration error.

To put those numbers into some perspective, on Sunday April 24th we measured 0.089µSv/hr in the air and 0.227µSv/hr on the ground at in the Silver Lake neighborhood of Los Angeles. Furthermore in Japan, radiation worker dose limits pre-Fukushima were 100 mSv/yr and the dose limit for normal person is 1 mSv/yr. 50µSv/hr is equivalent to annual dosage of 438 mSv which is more than 4x higher than the limit for nuclear radiation workers.

There are caveats to those numbers of course and as I mentioned the Sievert is the subject of some disagreement in and of itself. Additionally those limits may be focused primarily on high energy gamma, where as our sensors measure alpha and beta which are included in our µSv/hr measurements. Some sensors only measure high energy gamma. Alpha and beta particles are slower and penetrate less so may be considered less dangerous for exposure, but when ingested or inhaled can concentrate in certain organs and cause even more damage than a blast of high energy gamma. In other words, 50µSv/hr on the wall might end up being concentrated into a tiny 1cc square in your thyroid and might end up causing a much more concentrated dose into a particular set of cells than say a 50µSv/hr blast at your body with high energy gamma which would hit all of your cells mostly evenly. Think of the difference between the concentration of radiation used for killing cancer cells vs the wide spread used in an xray. Even that is confusing but we’ve found this infographic to be helpful in understanding different kinds of radiation and doses.

Again we want to make it clear that we are not radiation experts nor health physicists – we aren’t making any claim about how safe, or not, any of these measurements might be – rather we are trying to find and provide data that could be important for residents of these areas so that they can make informed decisions on their own. It’s one thing to be told everything is fine, it’s another thing to have access to the actual measurements and make that decision on your own. That said we are actively looking for experts to help us interpret this data and improve our protocols. If you or someone you know can help us there please get in touch. We expect to continually review and revise our methods as we continue to learn more about this ourselves. This is just the first of many runs we’ll be making in Japan, and with each one we plan to distribute more sensors to help build a clearer picture of what is happening on on ongoing basis.

These efforts have so far been funded by the kindness and donations of a few people but we’re going to need more financial help to keep this up. If you’d like to chip in a few dollars, please check out our kickstarter fundraiser. Thanks so much.

INFORMATION WITHHELD
http://nytimes.com/2011/08/09/world/asia/09japan.html
by Norimitsu Onishi and Martin Fackler / August 8, 2011

The day after a giant tsunami set off the continuing disaster at the Fukushima Daiichi nuclear plant, thousands of residents at the nearby town of Namie gathered to evacuate. Given no guidance from Tokyo, town officials led the residents north, believing that winter winds would be blowing south and carrying away any radioactive emissions. For three nights, while hydrogen explosions at four of the reactors spewed radiation into the air, they stayed in a district called Tsushima where the children played outside and some parents used water from a mountain stream to prepare rice. The winds, in fact, had been blowing directly toward Tsushima — and town officials would learn two months later that a government computer system designed to predict the spread of radioactive releases had been showing just that. But the forecasts were left unpublicized by bureaucrats in Tokyo, operating in a culture that sought to avoid responsibility and, above all, criticism. Japan’s political leaders at first did not know about the system and later played down the data, apparently fearful of having to significantly enlarge the evacuation zone — and acknowledge the accident’s severity. “From the 12th to the 15th we were in a location with one of the highest levels of radiation,” said Tamotsu Baba, the mayor of Namie, which is about five miles from the nuclear plant. He and thousands from Namie now live in temporary housing in another town, Nihonmatsu. “We are extremely worried about internal exposure to radiation.” The withholding of information, he said, was akin to “murder.”

In interviews and public statements, some current and former government officials have admitted that Japanese authorities engaged in a pattern of withholding damaging information and denying facts of the nuclear disaster — in order, some of them said, to limit the size of costly and disruptive evacuations in land-scarce Japan and to avoid public questioning of the politically powerful nuclear industry. As the nuclear plant continues to release radiation, some of which has slipped into the nation’s food supply, public anger is growing at what many here see as an official campaign to play down the scope of the accident and the potential health risks. Seiki Soramoto, a lawmaker and former nuclear engineer to whom Prime Minister Naoto Kan turned for advice during the crisis, blamed the government for withholding forecasts from the computer system, known as the System for Prediction of Environmental Emergency Dose Information, or Speedi. “In the end, it was the prime minister’s office that hid the Speedi data,” he said. “Because they didn’t have the knowledge to know what the data meant, and thus they did not know what to say to the public, they thought only of their own safety, and decided it was easier just not to announce it.”

In an interview, Goshi Hosono, the minister in charge of the nuclear crisis, dismissed accusations that political considerations had delayed the release of the early Speedi data. He said that they were not disclosed because they were incomplete and inaccurate, and that he was presented with the data for the first time only on March 23. “And on that day, we made them public,” said Mr. Hosono, who was one of the prime minister’s closest advisers in the early days of the crisis before being named nuclear disaster minister. “As for before that, I myself am not sure. In the days before that, which were a matter of life and death for Japan as a nation, I wasn’t taking part in what was happening with Speedi.” The computer forecasts were among many pieces of information the authorities initially withheld from the public. Meltdowns at three of Fukushima Daiichi’s six reactors went officially unacknowledged for months. In one of the most damning admissions, nuclear regulators said in early June that inspectors had found tellurium 132, which experts call telltale evidence of reactor meltdowns, a day after the tsunami — but did not tell the public for nearly three months. For months after the disaster, the government flip-flopped on the level of radiation permissible on school grounds, causing continuing confusion and anguish about the safety of schoolchildren here in Fukushima.

Too Late
The timing of many admissions — coming around late May and early June, when inspectors from the International Atomic Energy Agency visited Japan and before Japan was scheduled to deliver a report on the accident at an I.A.E.A. conference — suggested to critics that Japan’s nuclear establishment was coming clean only because it could no longer hide the scope of the accident. On July 4, the Atomic Energy Society of Japan, a group of nuclear scholars and industry executives, said, “It is extremely regrettable that this sort of important information was not released to the public until three months after the fact, and only then in materials for a conference overseas.” The group added that the authorities had yet to disclose information like the water level and temperature inside reactor pressure vessels that would yield a fuller picture of the damage. Other experts have said the government and Tokyo Electric Power Company, known as Tepco, have yet to reveal plant data that could shed light on whether the reactors’ cooling systems were actually knocked out solely by the 45-foot-tall tsunami, as officials have maintained, or whether damage from the earthquake also played a role, a finding that could raise doubts about the safety of other nuclear plants in a nation as seismically active as Japan.

Government officials insist that they did not knowingly imperil the public. “As a principle, the government has never acted in such a way as to sacrifice the public’s health or safety,” said Mr. Hosono, the nuclear disaster minister. Here in the prefecture’s capital and elsewhere, workers are removing the surface soil from schoolyards contaminated with radioactive particles from the nuclear plant. Tens of thousands of children are being kept inside school buildings this hot summer, where some wear masks even though the windows are kept shut. Many will soon be wearing individual dosimeters to track their exposure to radiation. At Elementary School No. 4 here, sixth graders were recently playing shogi and go, traditional board games, inside. Nao Miyabashi, 11, whose family fled here from Namie, said she was afraid of radiation. She tried not to get caught in the rain. She gargled and washed her hands as soon as she got home. “I want to play outside,” she said. About 45 percent of 1,080 children in three Fukushima communities surveyed in late March tested positive for thyroid exposure to radiation, according to a recent announcement by the government, which added that the levels were too low to warrant further examination. Many experts both in and outside Japan are questioning the government’s assessment, pointing out that in Chernobyl, most of those who went on to suffer from thyroid cancer were children living near that plant at the time of the accident.

Critics inside and outside the Kan administration argue that some of the exposure could have been prevented if officials had released the data sooner. On the evening of March 15, Mr. Kan called Mr. Soramoto, who used to design nuclear plants for Toshiba, to ask for his help in managing the escalating crisis. Mr. Soramoto formed an impromptu advisory group, which included his former professor at the University of Tokyo, Toshiso Kosako, a top Japanese expert on radiation measurement. Mr. Kosako, who studied the Soviet response to the Chernobyl crisis, said he was stunned at how little the leaders in the prime minister’s office knew about the resources available to them. He quickly advised the chief cabinet secretary, Yukio Edano, to use Speedi, which used measurements of radioactive releases, as well as weather and topographical data, to predict where radioactive materials could travel after being released into the atmosphere. Speedi had been designed in the 1980s to make forecasts of radiation dispersal that, according to the prime minister’s office’s own nuclear disaster manuals, were supposed to be made available at least to local officials and rescue workers in order to guide evacuees away from radioactive plumes. And indeed, Speedi had been churning out maps and other data hourly since the first hours after the catastrophic earthquake and tsunami. But the Education Ministry had not provided the data to the prime minister’s office because, it said, the information was incomplete. The tsunami had knocked out sensors at the plant: without measurements of how much radiation was actually being released by the plant, they said, it was impossible to measure how far the radioactive plume was stretching. “Without knowing the strength of the releases, there was no way we could take responsibility if evacuations were ordered,” said Keiji Miyamoto of the Education Ministry’s nuclear safety division, which administers Speedi.

The government had initially resorted to drawing rings around the plant, evacuating everyone within a radius of first 1.9 miles, then 6.2 miles and then 12.4 miles, widening the rings as the scale of the disaster became clearer. But even with incomplete data, Mr. Kosako said he urged the government to use Speedi by making educated guesses as to the levels of radiation release, which would have still yielded usable maps to guide evacuation plans. In fact, the ministry had done precisely that, running simulations on Speedi’s computers of radiation releases. Some of the maps clearly showed a plume of nuclear contamination extending to the northwest of the plant, beyond the areas that were initially evacuated. However, Mr. Kosako said, the prime minister’s office refused to release the results even after it was made aware of Speedi, because officials there did not want to take responsibility for costly evacuations if their estimates were later called into question.

A wider evacuation zone would have meant uprooting hundreds of thousands of people and finding places for them to live in an already crowded country. Particularly in the early days after the earthquake, roads were blocked and trains were not running. These considerations made the government desperate to limit evacuations beyond the 80,000 people already moved from areas around the plant, as well as to avoid compensation payments to still more evacuees, according to current and former officials interviewed. Mr. Kosako said the top advisers to the prime minister repeatedly ignored his frantic requests to make the Speedi maps public, and he resigned in April over fears that children were being exposed to dangerous radiation levels. Some advisers to the prime minister argue that the system was not that useful in predicting the radiation plume’s direction. Shunsuke Kondo, who heads the Atomic Energy Commission, an advisory body in the Cabinet Office, said that the maps Speedi produced in the first days were inconsistent, and changed several times a day depending on wind direction. “Why release something if it was not useful?” said Mr. Kondo, also a retired professor of nuclear engineering at the University of Tokyo. “Someone on the ground in Fukushima, looking at which way the wind was blowing, would have known just as much.”

Mr. Kosako and others, however, say the Speedi maps would have been extremely useful in the hands of someone who knew how to sort through the system’s reams of data. He said the Speedi readings were so complex, and some of the predictions of the spread of radiation contamination so alarming, that three separate government agencies — the Education Ministry and the two nuclear regulators, the Nuclear and Industrial Safety Agency and Nuclear Safety Commission — passed the data to one another like a hot potato, with none of them wanting to accept responsibility for its results. In interviews, officials at the ministry and the agency each pointed fingers, saying that the other agency was responsible for Speedi. The head of the commission declined to be interviewed. Mr. Baba, the mayor of Namie, said that if the Speedi data had been made available sooner, townspeople would have naturally chosen to flee to safer areas. “But we didn’t have the information,” he said. “That’s frustrating.” Evacuees now staying in temporary prefabricated homes in Nihonmatsu said that, believing they were safe in Tsushima, they took few precautions. Yoko Nozawa, 70, said that because of the lack of toilets, they resorted to pits in the ground, where doses of radiation were most likely higher. “We were in the worst place, but didn’t know it,” Ms. Nozawa said. “Children were playing outside.” A neighbor, Hiroyuki Oto, 31, said he was working at the plant for a Tepco subcontractor at the time of the earthquake and was now in temporary lodging with his wife and three young children, after also staying in Tsushima. “The effects might emerge only years from now,” he said of the exposure to radiation. “I’m worried about my kids.”

Seeds of Mistrust
Mr. Hosono, the minister charged with dealing with the nuclear crisis, has said that certain information, including the Speedi data, had been withheld for fear of “creating a panic.” In an interview, Mr. Hosono — who now holds nearly daily news conferences with Tepco officials and nuclear regulators — said that the government had “changed its thinking” and was trying to release information as fast as possible. Critics, as well as the increasingly skeptical public, seem unconvinced. They compare the response to the Minamata case in the 1950s, a national scandal in which bureaucrats and industry officials colluded to protect economic growth by hiding the fact that a chemical factory was releasing mercury into Minamata Bay in western Japan. The mercury led to neurological illnesses in thousands of people living in the region and was captured in wrenching photographs of stricken victims. “If they wanted to protect people, they had to release information immediately,” said Reiko Seki, a sociologist at Rikkyo University in Tokyo and an expert on the cover-up of the Minamata case. “Despite the experience with Minamata, they didn’t release Speedi.”

In Koriyama, a city about 40 miles west of the nuclear plant, a group of parents said they had stopped believing in government reassurances and recently did something unthinkable in a conservative, rural area: they sued. Though their suit seeks to force Koriyama to relocate their children to a safer area, their real aim is to challenge the nation’s handling of evacuations and the public health crisis. After the nuclear disaster, the government raised the legal exposure limit to radiation from one to 20 millisieverts a year for people, including children — effectively allowing them to continue living in communities from which they would have been barred under the old standard. The limit was later scaled back to one millisievert per year, but applied only to children while they were inside school buildings. The plaintiffs’ lawyer, Toshio Yanagihara, said the authorities were withholding information to deflect attention from the nuclear accident’s health consequences, which will become clear only years later. “Because the effects don’t emerge immediately, they can claim later on that cigarettes or coffee caused the cancer,” he said. The Japanese government is considering monitoring the long-term health of Fukushima residents and taking appropriate measures in the future, said Yasuhiro Sonoda, a lawmaker and parliamentary secretary of the Cabinet Office. The mayor of Koriyama, Masao Hara, said he did not believe that the government’s radiation standards were unsafe. He said it was “unrealistic” to evacuate the city’s 33,000 elementary and junior high school students. But Koriyama went further than the government’s mandates, removing the surface soil from its schools before national directives and imposing tougher inspection standards than those set by the country’s education officials. “The Japanese people, after all, have a high level of knowledge,” the mayor said, “so I think information should be disclosed correctly and quickly so that the people can make judgments, especially the people here in Fukushima.”