Are
the risks worth the wow? The answer, increasingly, is
no.
As stories about mercury spills at schools tumble
across newspaper headlines, more states and districts
are deciding that the educational benefits that mercury
might have in lessons do not outweigh the hazards
associated with handling the toxic, and enticing,
element. Eleven states, at a minimum, have taken steps
to rid schools of the substance through legislation or
other means.
"It's too dangerous," declared Kenneth R.
Roy, the head of the safety advisory board for the
National Science Teachers Association.
When mercury—specifically, metallic mercury—is
released, it breaks apart into tiny beads and releases a
vapor that can cause shortness of breath, nausea,
vomiting, diarrhea, and possibly death.
At least seven U.S. schools, in separate incidents,
have been evacuated because of major spills so far this
school year.
The latest, and possibly the most dramatic, incident
happened at Ballou Senior High School in Washington this
month.
After taking about half a cup of mercury from an
unlocked science lab at the 1,300-student school on Oct.
2, a student shared it with some classmates, who played
with the dangerous material.
The student's actions resulted in a massive cleanup
involving school district officials, the District of
Columbia fire department's hazardous-materials team, the
federal Environmental Protection Agency, and the local
health department.
Nearly 300 people came into direct contact with the
mercury, and more than 1,200 students, teachers, and
staff members at Ballou High were screened for mercury
poisoning.
No one was identified as having symptoms of such
poisoning, but 165 people required additional checkups
as of last week, according to Briant K. Coleman, a
health department spokesman.
In addition, 86 houses were tested for mercury
exposure, 11 of which have shown elevated levels and
will need to be decontaminated, Mr. Coleman said.
Mercury was also found on one of five public buses
that city emergency workers examined and took out of
service, he said.
When the cleanup will be finished and what it will
cost were still up in the air last week.
Meanwhile, Ballou students are attending classes at
the former Washington Convention Center and taking field
trips to the capital's landmarks and museums.
'Anti-Social' Element
What
to do (and not do) in case of a
mercury spill
The U.S.
Environmental Protection Agency has
three sets of guidelines for cleaning up
mercury, depending on the size of the
spill. The following procedures pertain
to spills that commonly occur in
schools.
DO
Isolate the
area
Lower the temperature.
Open Windows.
Put all contaminated material, including
clothing, shoes, and bookbags, in a
sealed plastic bag.
Notify the local fire department and
public health officials.
If more than one pound (equal to two
tablespoons) of mercury is spilled, call
the National Response Center at (800)
424- 8802.
DON'T
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Some of the same properties that make mercury so
attractive are also what make it difficult to clean up.
Unlike water, which will adhere to almost anything,
mercury adheres to itself. To demonstrate that
principle, science teachers commonly have students
compare one graduated cylinder containing water and one
containing mercury, said Mr. Roy of the science
teachers' association.
The top of the water appears concave, while the
mercury appears convex because the glass sides of the
cylinder are attracting the water, and mercury is trying
to attract itself.
"Mercury tends to be anti-social," said Mr.
Roy, who is also the safety-compliance officer for the
8,000-student Glastonbury, Conn., school district.
That self-possessed property is why, when released,
mercury forms little balls that tend to roll into cracks
and crevices. Trying to sweep up the beads with a broom
and dustpan—a common mistake, according to Mr. Roy—
only spreads the mercury around more and releases its
toxic vapor.
In the case of a mercury spill, schools must
immediately isolate the area around the spill and shut
down the ventilation system, which can carry the vapors
throughout the building. They should also call the local
fire marshal, Mr. Roy advised.
Depending on the size of the spill, teachers may be
able to use specially designed cleanup kits that are
available from chemical-supply companies, he said.
Careful attention needs to be paid to students' and
teachers' clothing and shoes, because mercury can attach
itself to certain fibers and, as was the case in the
Washington spill, travel to students' homes.
"It is the gift that keeps on giving," Mr.
Roy said jokingly.
Even when mercury is not used in experiments or
demonstrations, it can show up in school science labs in
the form of such commonly used equipment as
thermometers, barometers, and manometers.
Now, many supply companies are sponsoring exchange
programs so that teachers can trade in their old devices
for newer models that are safer and more accurate, Mr.
Roy said.
Mercury is becoming so unpopular that at least 11
states—including Connecticut, Indiana, Kansas, Maine,
Maryland, Michigan, Minnesota, Oregon, Vermont,
Virginia, and Wisconsin— have introduced programs or
passed legislation to remove the metal from schools,
according to the Environmental Protection Agency.
The EPA will hold an online workshop Nov. 14 for
teachers and administrators to discuss different
mercury-reduction programs. More information on the
Webcast can be found at www.epa.gov/mercury/classroom.htm.
"The initiatives are there," Mr. Roy said.
"Unfortunately, some behaviors are very difficult
to change."
Costly Cleanup
Ingrained behavior is exactly what complicated
cleanup efforts in Onaway, Mich. Even though the
750-student district had rid its single school of
mercury three years ago, this fall three students took
about half a cup of mercury from an abandoned house last
month, brought it to school, and spilled it in a busy
hallway.
Then a well- intentioned custodian vacuumed it up,
said Superintendent Robert Szymoniak. "You don't do
that," Mr. Szymoniak emphasized. "That puts
mercury vapors in the air, where it is most
dangerous."
The custodian followed what was for years the
standard cleanup procedure at the school, Mr. Szymoniak
said. As soon as the superintendent heard about the
spill, he evacuated the school and hired a professional
company to test the air and decontaminate the building.
In the end, Onaway Area School was closed for four
days. The cleanup bill will amount to more than $40,000,
Mr. Szymoniak said. Because the students didn't know
what they had, they were not disciplined, he said.
In response to that kind of price tag, some school
administrators have decided to close down science labs
altogether, Mr. Roy said.
"Let's not throw the baby out with the bath
water," he said. Instead, Mr. Roy suggests that
science teachers receive annual professional-development
instruction on the topic, and that schools make their
laboratories safer. ("Science-Lab
Safety Upgraded After Mishaps," April 30,
2003.)
The federal Occupational Safety and Health
Administration, or OSHA, requires schools with science
labs to have a chemical-hygiene plan, outlining the
safety procedures and equipment employees should use
when dealing with potentially dangerous chemicals. In
essence, those plans promote "professional
responsibility," Mr. Roy said.
Still, he added, "most schools are handling this
responsibly."
