Hermmiston Herald
03/28/02 page A-1

Nerve agent more toxic than first believed

By Frank Lockwood
Staff writer

HERMISTON - Chemical warfare nerve agent stored at Umatilla and other sites
is more toxic than Oregon emergency managers once thought.

As a result, Irrigon residents may get electrically-operated home filters.
At the Umatilla Chemical Depot, rockets filled with the agent GB are
scheduled to be destroyed first, because of their higher risk compared with
VX-filled rockets. But the gap between the VX risk and the GB risk is
shrinking.

According John Yaquiant, of Soldier and Biological Chemical Command (SBCCOM) public affairs confirmed yesterday that VX is 10 times as potent than previously
thought, and perhaps even more potent than that. And according to the
Federal Register, VX is 12 times more potent than GB.

New toxicity standards, called Acute Exposure Guideline Levels (AEGLs), are
being developed for hazardous substances, including chemicals stored at
Umatilla Chemical Depot. Emergency managers have decided to use "interim"
figures based on those AEGLs which are presently available.

Morrow County Emergency Manager Casey Beard spoke at Thursday's meeting of
the Citizens Advisory Commission, held at Good Shepherd Medical Center in
Hermiston. Beard wants to purchase home air-filtering units for up to a
thousand residents living nearest the depot.

The home filtration unit, a Honeywell F-113, is about the size of a
residential, canister-style vacuum cleaner, and makes a noise similar to
that of a window air conditioner. Residents receiving the units, those
within three and a half miles of the depot, live in Irrigon.

"If you draw a circle, Hermiston is probably outside that range," Beard
said.

Near a ground zero location, high concentrations could cause nerve gas to
more easily seep through small cracks in a "safe room" where people are
sheltering in place. The simple, industrial, recirculating air-filter has
proven effective in removing that gas at a test cottage at Aberdeen. Md.,
Beard said.

Inside the test cottage, a unit was placed in a sealed room resembling
a sheltering-in-place situation. Experimenters pumped actual nerve gas into
the test cottage, Beard said, and the monitors showed that small amounts of
nerve gas would seep into the safe room.

Honeywell's standard, light-weight filters, impregnated with carbon, removed
most of that gas, but replacing that lighter filter with 14 pounds of
activated charcoal "substantially" increased safety by extending the time in
which people would be able to remain sheltered in place, Beard said. The
longer people can safely shelter in place, the better, when someone is
trying to reach and help them.

Costs

By partnering with Alabama, Oregon could save money. The Honeywell unit's
suggested price is $349, but if Umatilla and Morrow CSEPPs were able to
partner with Alabama, they could get the unit for $211 each, Beard said.

People could also use the air filters daily, if they wanted to buy a
standard filter, Beard said. The unit and the activated charcoal filter,
however, should be kept in the shelter-in-place safe-room, he said.
Emergency planners are upgrading protective measures partly because
chemicals being stored at Umatilla are more toxic than formerly believed.

Several factors are driving CSEPP's new activities:

• Original health effects studies left out civilians - the young, the
  elderly, the infirm. Original toxicity estimates for chemical agent were
  intended for soldiers. "The general population does not consist of only
  healthy, young adult males, so we wanted to change the standard," Beard
  said.
• Computer modeling improved. The new, PUFF computer models added weather
  and terrain into the risk analysis and projected more realistic plume paths
  in case of an accidental release chemical agent into the environment.
• Chemical warfare agent, in general, is more toxic than originally
  believed. The National Advisory Committee for Acute Exposure Guidelines
  (AEGLs) for Hazardous Substances is developing guidelines on a continuing
  basis to provide agencies with information on short-term exposures to
  hazardous chemicals.

New, Interim Standards

The AEGLs give estimates of potential effects of exposure to different
concentrations of agent over time. Below certain levels there are no
noticeable effects. When the no-noticeable-effects level is exceeded,
depending on the concentration of agent and the amount of time a victim is
exposed, the effects are: notable discomfort (AEGL-1), serious, long-lasting
adverse health effects and impaired ability to evacuated (AEGL-2), and
life-threatening health effects (AEGL 3).

AEGL-1 effects are not disabling, but temporary and reversible at the end of
exposure. They could include miosis (pin-pointing of the pupils), headaches,
eye pain, tightness of the chest, and inflammation of mucous membranes for
GB and VX, or minor eye irritation for mustard.

AEGL-2 effects may be irreversible, and, depending on what agent is
involved, could include miosis, labored breathing (GB and VX) or swelling
and discharge in tissues, and eye irritation (Mustard).

AEGL-3 exposures may be fatal.

AEGLs take into account the fact that low concentrations over longer times
affect the body differently than higher concentrations over shorter times.
For each AEGL, the EPA defines concentrations for five time periods: 10
minutes, 30 minutes, 60 minutes, 240 minutes (six hours), and 480 minutes (8
hours).

The figures used by Oregon Health Department and CSEPP are considered
"interim" standards. The figures on chemical warfare agent were expedited in
a study which will complete standards for a wider range of chemicals.

CSEPP, Army, and public health officials say incineration schedules will not
suffer setbacks as a result of the new toxicity standards, but some
emergency measures will have to be adjusted.