NUCLEONICS WEEK - August 22, 2002
SOURCE DESTROYED ACCIDENTALLY
DURING TRANSFER AT PARIS AIRPORT
A medium-size iodine-131 source was dropped from a
transfer dolly and crushed in Roissy Charles de Gaulle airport
near Paris early this week, dispersing radioactive powder in a
transit area between two terminals, French authorities said Aug. 20.
Officials at regulatory agency DGSNR and the Institute of
Radiological Protection and Nuclear Safety (IRSN) said the
Aug. 17 incident was "highly unusual" because the iodine
package had been "completely destroyed."
Patrick Gourmelon, head of IRSN's dosimetry and health
protection department, said the 5-gigabecquerel source (about
100 millicuries) would have caused only "very low doses,"
below the 1 milliSievert limit for public exposure, because the
volatile iodine was dispersed over a wide area. But Jean-Luc
Pasquier, head of IRSN's Le Vesinet site (the former rad
protection office OPRI), said the incident is further demonstration
that "there's a dysfunction in transfer of radioactive
materials at Roissy." IRSN issued a report on the incident late
Aug. 20 following an inspection at the airport Aug. 19
(www.irsn.org).
The capsule containing powdered sodium iodide, sent by
CIS-Bio International in Saclay, was en route to a hospital in
Zagreb, where it was to have been used to treat a cancer patient,
Pasquier said. At the Paris airport, it was handled by a
transit company and its subcontractors. The crushed package
was found on the ground by gendarmes.
The incident highlighted the problems of shipping small
or medium-sized radioactive sources, which until recently
have been essentially uncontrolled in France. The French
nuclear safety authority only recently was given jurisdiction
over radiation protection and radioactive sources, and although
in principle DGSNR's predecessor agency, DSIN, had
authority over nuclear materials transportation, in reality the
agency hasn't had the resources to inspect and police the
hundreds of thousands of "small nuclear" transports that occur
in France every year.
The way the iodine package was damaged-falling off a
dolly in transit and believed being crushed by a truck-
"shows that radioactive packages are handled like noodles or
potatoes," commented one French expert. He said DGSNR is
only just getting a handle on the problem, but there still appears
to be confusion within the French bureaucracy over
which agency or ministry is responsible for transport of small sources.
The problem has taken on a higher profile since Sept. 11,
2001 in light of fears that terrorists might seize on a radioactive
source to use as a threat or to incorporate in a so-called dirty bomb.
More FedEx Analysis
The dysfunction of the source shipment system was high-lighted
in early January when an iridium-192 package en
route at Roissy airport from Studsvik in Sweden to Memphis,
Tenn. and New Orleans, La. was found to be leaking on arrival
(NW, 10 Jan., 1). Because of its size, the source was enclosed
in a Type B container, with more stringent requirements,
but subsequent investigations showed the lids on two
of three shipping tubes had not been properly screwed on.
In May and June, DGSNR announced that two employees
at Federal Express' Roissy hub had received doses estimated
at about 15 and 100 milliSievert, respectively, showing the
package was already leaking when it arrived in Paris.
The doses are much higher than the limit for the general
public, 1 mSv, but lower than the threshold for detection with
traditional cell-count methods used in other countries, about
150 mSv. Only IRSN counts enough cells to find effects under
that threshold, experts said. In the wake of the June finding,
DGSNR asked FedEx to designate a further batch of
employees who might have come into contact with the irradiating package.
This week, IRSN's Gourmelon said results of the latest
batch of detailed chromosome readings of FedEx personnel,
just completed, had "not changed the picture" regarding the
radiological impact of the iridium package, i.e., no further
unusually high dose had been detected. He added that the cost
of reading the 2,000 blood cells required to detect such relatively
low doses was prohibitive, making it unlikely French
authorities would order further investigations of the incident.
Meanwhile, sources with the World Nuclear Transport
Institute (WNTI) said the institute intended to "get more in-
volved" in source transports. WNTI up to now has concentrated
on the high-profile nuclear fuel cycle transport its members
represent. Last month it published an issue brief outlining
transport industry response to new regulations, known as ST-1,
that since Jan. 1 require rad protection programs for all
kinds of nuclear material transport. The issue brief said WNTI
investigations, based on experience of actual transports,
showed the expected maximum dose to handlers, crew and
the public for shipment of all types of fuel cycle materials was
"unlikely" to exceed 1,000 microSievert.
That result contrasts with the 100 mSv received by the
FedEx worker in Paris. "If a dose like that had been received
in the nuclear fuel industry, there would have been public
outcry," said a WNTI source. He said that partly because "the
anti-nuclear power lobby would try to connect these incidents"
to nuclear fuel transport, WNTI wants to "play a role"
in helping make sure smaller transports are kept safe.
He said that presently, WNTI "doesn't know very much"
about the other part of the transport industry-that not dealing
with fuel cycle materials-but "within a year we expect to be
paying more attention" to that sector. He said WNTI "can do
a lot to help the organizations involved" to set up rad protection
programs based on its own experience and interface with
regulators worldwide. He said the institute will be contacting
those organizations with a view to collecting information and
inviting them to join WNTI.-Ann MacLachlan, Paris