Tuesday, October 30, 2007

Radiological Exposure Testing: A Wide Gap

Just a few days after the publication of HSPD 21: Public Health and Medical Preparedness and TOPOFF IV exercise, which focused on a radiological disaster scenario, the House Subcommittee on Investigations and Oversight - House Science and Technology Committee has released a brief report that should raise the eyebrows of anyone involved in disaster preparation at any level.

The report analyzes the ability of U.S. laboratories to test for radiological contamination among the population of those potentially affected by a radiological event. We have to point out that a "dirty bomb" is one of the more likely "mass effect" attacks. It is perhaps the least technologically sophisticated of these attacks, requiring a radioactive source and a conventional explosive (or another mechanism for releasing radioactivity). And the materials are out there. Earlier this year, the Canadian
Security Intelligence Service rated a dirty bomb attack as the most likely WMD attack. (See this post.)

Let's also recall that the Redefining Readiness Workgroup has found that, in the event of a "dirty bomb" attack, only about 59% of citizens would shelter in place (unless they were at home). This would make them more likely to become exposed to radioactive materials.

So reality suggests that such an attack is likely and that many people may be at risk of contamination. We should be prepared. Are we?

The Subcommittee found that in some key respects we are not. Most notably, the laboratory infrastructure for testing radiation is insufficient, despite the requirement found in the National Planning Scenarios:

One of the key assumptions in National Planning Scenario #11 is that all potentially exposed individuals (an estimated 100,000 people, including 20,000 victims with detectible contamination) will be tested for radiological exposure and/or contamination and that a valid method exists for testing these clinical specimens.

Yet, today validated methods to test clinical specimens in a radiological emergency exist for only six of the 13 highest priority radioisotopes most likely to be used in a terrorist scenario. For those isotopes for which “validated” methods do exist screening 100,000 individual clinical specimens in the wake of a radiological attack could take more than four years to complete due to the current shortfall in radiochemistry laboratories, personnel and equipment. Environmental sampling could take as long as six years to complete given the current capacity and capabilities of the U.S. radiochemistry laboratory infrastructure.
Picture the crisis of confidence that could result from this scenario: A dirty bomb explodes. Tens of thousands of people downwind fear or suspect they've been exposed to radiation. (It's worth remembering that in the immediate aftermath, it will not be clear whether the bomb was dirty. You can't tell the difference between an IED and a dirty bomb just by looking.) They sensibly want to get tested for exposure. And public officials have to tell them to wait in line - for months or perhaps years before the test can be run.

People will be likely to demand testing, and the only way to do it is with lab testing:
[Laboratory analysis] will be necessary for the thousands of “exposed” individuals to determine whether they suffer from internal contamination and to identify appropriate medical treatment. Clinical analysis may also be demanded by those medically unaffected, but fearful of contamination nonetheless.
As the subcommittee puts it:
[I]n any real world event the critical lack of a sufficient laboratory capacity will delay appropriate public health care actions and plans, increase public panic, degrade public trust in government officials and increase the economic losses due to delays in assessment and cleanup.

While the human health consequences from an RDD attack are likely to be small, the public outcry for detailed clinical health assessments confirming their lack of radiological contamination is likely to be tremendous. The need to provide these individuals – expected to number in the tens of thousands – with a clean bill of health will help to reassure them psychologically and emotionally that they have not suffered harm and will enhance their trust in the government’s ability to effectively recover from the incident.
So how have we gotten into this mess? The main problem is systemic:
[T]he only current method for determining internal contamination is through laborious laboratory analysis, often involving a 24-hour urine collection, days to process the results and still more time to interpret them accurately.
I should note, however, that researchers are working to speed the testing process, as noted in this post.

But at present the long, hard way is the only way. The CDC is supposed to do the testing, but it has insufficient capacity:
National Preparedness Guidelines released last month by the Department of Homeland Security call for the nation’s public health laboratory infrastructure to be able to rapidly detect and accurately identify chemical, radiological and biological agents and “produce timely and accurate data to support ongoing public health investigations and the implementation of appropriate preventative or curative countermeasures.”

The Centers for Disease Control and Prevention (CDC) is tasked with monitoring, assessing and coordinating follow up medical monitoring on people’s health as a result of exposure to or contamination with radiological materials in a national emergency.

The CDC, for instance, currently has no capacity to analyze seven of thirteen of the most likely radioisotopes that would be present in a radiological or nuclear incident, according to information provided to the Subcommittee. For some of the most likely “dirty bomb” or RDD scenarios the CDC is currently capable of processing only 65 human samples per day. At that rate it would take more than four years to process 100,000 clinical samples as called for in National Planning Scenario #11.
Other problems could plague the response to a radiological incident as well. For instance, environmental testing could be just as cumbersome if not moreso:
The U.S. ability to evaluate potential radiological contamination on the environmental side also lacks the resources to effectively respond to a radiological emergency. White House National Planning Scenario #11 demands that the EPA be capable of analyzing more than 350,000 environmental samples in the 12 month period following a radiological attack.

Depending on the radioisotope used in the attack, however, it would take two to six years to complete that task given the current available laboratory facilities today, according to a March 2007 draft EPA report.
And roles have not been fully defined:
A recent interagency (draft) report on responding to a radiological attack found that the specific roles and responsibilities of federal agencies tasked with responding to a radiological event have not been clearly defined in the National Nuclear/Radiological Incident Annex, upon which these agencies rely.
Which is kind of a big deal, as there are many agencies that can play a part in such a response. See this article in Nuclear News from Sept. 2006.

For local disaster planners, information like this provides an opportunity for improving preparations. Let's say that these systemic problems persist for the forseeable future. This is likely, given that you can't just spin up one of these laboratories at a moment's notice. What can a local disaster planner do? A few ideas:

Educate. Citizens who are prepared to shelter in place are less likely to become contaminated. Also, if they understand the health risks involved with a dirty bomb attack, they are likely not to panic and may be less likely to succumb to the "worried well" phenomenon. Depending on the amount of radioactive material and the effectiveness of its dispersal, it is possible that the health effects may be limited to a relatively small area. The better informed citizens are, the better they will be able to respond in the immediate aftermath.

Communicate. Ensure that communications plans are in effect for a radiological disaster. This is a different risk than most. Through experience, most people have a reasonable understanding of natural disasters. They can rationalize accidents. But radiation - unseen, unfelt - is something that scares people. They don't know what to do.

Decontaminate. Set up decontamination stations - as large as possible - so that those who suspect that they might be contaminated can take action and get cleaned up. In the aftermath of a major incident, it is important for people to be able to take positive action and improve their situation.

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