Monday, October 26, 2015

Probably an Under-Estimate of Exposure

The Mainichi reported on a survey of Self-Defense workers' radiation exposure from the Fukushima disaster recovery and rescue operations. 

 After the excerpt from the Mainichi, I will post some material from my 2013 book, Fukushima and the Privatization of Risk.
“Over 1,000 workers around Fukushima plant exposed to radiation above 1 millisievert,” The Mainichi, October 27, 2015.

"The survey covered about 2,800 members of the Self-Defense Forces who worked within a 20-kilometer radius of the Fukushima No. 1 plant between March 12, 2011 -- the day after the outbreak of the disaster -- and March 31 of that year, along with roughly 170 police officers and firefighters. Their tasks included guiding evacuees, performing search and rescue operations, and transporting injured people. Since all of them were wearing full-body radiation suits and masks, their internal radiation exposure was presumed to be zero in the survey. Data was collected from individual dosimeters measuring external exposure." The survey found that 62 percent of Self-Defense Force members received a dose of less than 1 millisievert of radiation, while the remaining 38 percent registered levels upwards of 1 millisievert. The highest figure was 10.8 millisieverts.
Ok so The Mainichi is reporting that the highest exposure figure measured for Self Defense Forces was for 10.8 millisieverts. It is presumed that workers had zero internal exposure because they were wearing full suits.

However, we learned from the Ebola hospital outbreaks that it is difficult to shut off entirely from a contaminating environment. In particular, its easy to become contaminated because of poor seals, faulty or limited ecapabilities equipment, and through the process of removing contaminated protective gear.

More generally, I question the 10.8 millisievert level for two reasons. 

First, the badge system was described in the Japanese news media as underestimating exposure levels by seven times when compared to an atmospheric monitoring technique:
Lower radiation readings proposed to speed return of Fukushima evacuees (2013, November 9). The Asahi Shimbun. Available
The Nuclear Regulation Authority has drafted a proposal to accelerate the return home of Fukushima nuclear disaster evacuees by using radiation readings that tend to be lower than the ones now officially used. The NRA wants residents to take radiation measurements with dosimeters instead of relying on the current government system of determining levels through aircraft monitoring…. (“Lower Radiation Readings,” 2013)

Secondarily, Fukushima workers reportedly had much, much higher levels of exposure recorded for the Self Defense forces, but these reported discrepancies are hard to reconcile.

Firefighters who responded to the Fukushima disaster were exposed to the radiation from the fire in spent fuel pool #4 and from the reactor fires in units 1-3. Surely the firefighters, as members of the Self Defense forces, would have higher levels of exposure than reported above.

Here is an excerpt from my book, Fukushima and the Privatization of Risk, Chapter III concerning the conditions for workers at the Daiichi site:

.... During the early days of the disaster workers did not receive dosimeters to monitor their radiation exposure.[i] The command center used by workers during cleanup was subsequently revealed to be contaminated, potentially causing thousands of workers to ingest radioactive particles. One worker waded into radioactive water and was burned because he was not wearing appropriate protection. Workers were not required to wear waterproof ponchos when it rained, although rainwater is known to wash out radioactive contamination in the air.  

Testing of workers found hundreds were contaminated. In December of 2012, The Asahi Shimbun reported that TEPCO found 178 workers whose thyroid glands evidenced exposure levels exceeding 100 millisieverts.[ii] One hundred and sixty-three workers were calculated to have had thyroid doses exceeding 200 millisieverts. The highest dose recorded was 11,800 millisieverts, although two workers were found with exposure levels over 10,000 millisieverts.

Ilya Perlingieri described these workers as expendable in her essay ‘No Protection for Fukushima’s Expendable Citizens or Us’:

On March 14, the Japanese industry of Health and Labor raised ‘the maximum [radiation] dose for workers to 250 mSv [milli Sieverts] a year’ an increase in exposure from the previous 100 mSv. These new figures are also drastically higher than those from the International Commission on Radiological Protection's guidelines stipulating a maximum of 20 mSv a year.[iii]

The Mainichi reported on 22 June 2011 that the whereabouts of 30 former Fukushima plant workers were unknown: ‘The workers' names were listed in records showing that they had been loaned dosimeters, but when the plant's operator, TEPCO, contacted the companies they were associated with, the companies replied that there was no record of those workers.’[iv] By August 2011, TEPCO was reporting that the whereabouts of 143 workers was unknown.[v] TEPCO also reported in August that a 40 year old worker died of acute leukemia after working at the plant for seven days.[vi] In July of 2012, it was revealed that a subcontractor at the Fukushima plant had required workers to blanket their personal radiation detection devices in lead in an effort to keep their official radiation exposure under the safety threshold.[vii]  In November of 2012, The Asahi Shimbun reported that workers involved in the disaster cleanup were not being given the special allowance of between 3,300 yen and 10,000 yen allocated by the Environment Ministry for workers in radiation contaminated areas. The article implied that the six general contractors were withholding the allowances. The Asahi Shimbun noted that it had found instances of nonpayment in all six projects of 100 million yen each.[viii]

            Concerns about the risks posed to workers continued to be reported in the Japanese media through the end of 2012. In December of 2012, The Asahi Shimbun interviewed workers who claim that TEPCO assigned contractors to the highest radiation areas and that these contractors feared for their health but were driven by economic imperatives to take these dangerous jobs: ‘Workers come from around the country because they are willing to work even at a nuclear plant due to the economic slump,’ one worker said.[ix] He continued: ‘Many businesses siphon off part of their wages, taking advantage of their vulnerable positions.’ Another worker in his 20s who was interviewed asserted ‘I was told to work at the plant like a kamikaze pilot . . . I have no idea about how much radiation I was exposed to.’ The worker expressed concern for his future health and ability to produce healthy children. Unfortunately, the Japanese government’s difficulties in keeping track of contract workers and its decision to restrict cancer surveys for workers[x] may ultimately privatize the risks for health impacts when sickened former plant workers lack formal documentation of their time spent at the plant and/or their levels of radiation exposure.

[i] P. Dvorak (14 June 2011) ‘Japanese Nuclear Cleanup Workers Detail Lax Safety Practices at Plant’, The Wall Street Journal, A1, A12.

[ii] Y. Oiwa (1 December 2012) ‘High Thyroid Radiation Doses in 178 Fukushima Workers’, The Asahi Shimbun,, date accessed 7 December 2012.

[iii] I. Perlingieri (4 May 2011) ‘No Protection For Fukushima's ‘Expendable’ Citizens Or Us,’ Jeff Rense,, date accessed 9 July 2011.

[iv] ‘Whereabouts of 30 Nuclear Power Plant Subcontractors Unknown: Health Ministry’ (21 June 2011), The Mainichi,, date accessed 22 June 2011.

[v] ‘TEPCO Says It Has Lost Contact with 143 Nuclear Plant Workers’ (10 August 2011), Japan Today,, date accessed 11 August 2011.

[vi] O. Mitsuru (31 August 2012) ‘Japan Finds Radiation Spread Over a Wide Area’, The Wall Street Journal, A11.

[vii] Reuters (21 July 2012) ‘Japan Probes Under-Reporting of Fukushima Radiation Dosage’, The Washington Post,, date accessed 22 July 2012.

[viii] M. Aoki (5 November 2012) ‘Special Allowance Not Reaching Workers Involved in Disaster Cleanup’, The Asahi Shimbun,, date accessed 6 November 2012.

[ix] M. Aoki and T. Tada (9 December 2012) ‘Worker Wants New Government to Secure Safety at Fukushima Plant’, The Asahi Shimbun,, date accessed 10 December 2012.

[x] M. Aoki (21 November 2012) ‘Most Fukushima Nuke Plant Workers Ineligible for Free Cancer Checks’, The Asahi Shimbun,, date accessed 22 November 2012.


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