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Safe Science Series
Hazardous Chemical Removal
By Cliff Schrader
(Article #6)
Most schools have chemicals that should be eliminated. Some of the chemicals are extremely hazardous and others are a nuisance. In the past, unwanted chemicals were put in the trash or dumped down the drain. Environmental regulations and common sense tell us this method o f disposal is wrong.
When I started teaching at Dover High School in 1963, the chemistry laboratory had just been remodeled. I spent three days shelving the chemicals. I stored them alphabetically according to the name on the container, a method that made sense to me and was commonly used at this time. Although I was a chemistry major with a degree in science education as well, I had no classes or training in safety or the hazards of chemicals.
Is Ignorance Bliss?
I was aware of only the most obvious hazards. I knew concentrated sulfuric and nitric acids were very corrosive to clothing and skin and I had learned both lessons by intimate contact in the laboratory I knew arsenic and cyanide were poisons, as many people know that a compound of lithium is used to treat bipolar disorder. I had little knowledge of which chemicals were poisonous and had not heard of the L. D. 50 dose.
By watching movies I learned that nitroglycerine was an unstable and unpredictable explosive but knew nothing of explosives in general. When I picked up a quart bottle of picric acid I merely thought, I've never heard of this acid. I looked in the three chemistry books available to me which included Pauling's College Chemistry and two high school texts and found no information so I shelved it with P's . I noted it was a solid and the only other solid acid I knew about was carbolic acid, or phenol, used as an antiseptic by Joseph Lister in 1865. If the bottle had been labeled trinitrophenol I might have suspected it was dangerous, but I had only the common name and little awareness of potential hazards.
Don't Depend on Luck
More than a decade later I was at home reading The Science Teacher and learned a teacher had been severely injured when a bottle of picric acid exploded. Anyone who had picric acid was advised to avoid touching the container and to call the fire department. I said to my wife; "I think I have some picric acid at school." The next day I saw the quart bottle through the glass door of the cabinet. I informed the principal and called the fire department. The fire chief replied, "We don't handle picric acid; call the bomb squad." The bomb squad came that day ],removed the picric acid carefully, transporting it in an explosion box. I went with them when they exploded it at a nearby strip mine. The bomb experts compared the violence of the explosion to that of several sticks of dynamite.
I thought the picric acid was an aberration as a hazard and continued as before. We have found 10% of Ohio schools have at least one potential explosive, which requires a high hazard team. Occasionally, when I shelved the chemicals I reordered, I wondered about all the chemicals I never used. I assumed as I learned more about teaching I would know what they fore for and how to use them. I had more than 10 kilograms of various chemicals that I thought had a use in the lab.
Around 1980, Larry Flinn Jr. came to Ohio and gave an eye-opening presentation titled, "Your stockroom is a disaster waiting to happen." He related dozens of incidents that caused severe injury and property damage. He also described ways to prevent those accidents. His advice is in every Flinn Catalogue and has become the model for teachers who are informed and attentive to safety in the l/laboratory. Storing acids, flammables, and substances properly not only makes sense, it is the law.
After I spent two days reshelving chemicals, as Flinn suggested, I again wondered why I had more than ten kilograms of lead oxide, potassium cyanide, sulfur, sodium arsenate, sodium thiosulfate, sodium stearate, etc. even though I never used them. When I learned boric acid was too toxic for students to use in a simples laboratory experiment, I wondered about the hazards of the chemicals I never used. It was obvious that at least a third of them were obtained before World War II!
Perpetual Care = Perpetual Responsibility
Getting rid of what I didn't use was difficult and expensive. All such discarded chemicals are classed as waste and the school is perpetually responsible, even if we pay a contractor to remove and dispose of them. How do officials in a small school identify the chemicals to be disposed of and locate a reliable contractor?
Everyone wants to avoid making the problem worse. A chemical company near Times Beach, Missouri, hired a local contractor to dispose of 70 kiloliters of an oily residue. Since he had the contract to oil the unpaved roads in the area he decided to mix the oily residue with the road oil. Flies, birds, cats, and dogs started dropping dead. When horses began dying (62 in all) the source of the problem was located (high concentrations of dioxin) and the cleanup cost over $36 million of your tax money and mine. After this incident, laws were enacted to make the generator of waste perpetually responsible. Choosing a reliable waste disposal contractor is more important than finding the cheapest one.
Ohio's Solution
Discussions with other chemistry teachers in Ohio indicated nearly everyone had unwanted chemicals. It took a decade of committee work but Ohio has found a solution that could and should be adopted or adapted in every state. The problem of hazardous waste disposal is statewide and requires resources easily available at the state level. Without a statewide effort, the few schools that have resources remove hazardous chemicals, while most schools do nothing. The $3 million appropriated for Ohio is less than a tenth of the amount required to clean up the disaster in Missouri. The Hazardous Waste Removal Program (HWRP) in Ohio will pay for the removal and disposal of all chemicals that result from the instructional program. Not that custodial and maintenance materials are excluded. The program is voluntary and all final decisions are made locally. We learned that to get chemistry teachers, who are natural hoarders, to get rid of enough of their chemicals, a strung educational component was necessary. To participate in the HWRP schools must first send someone (we think the chemistry teacher is the right person) to a day long seminar. Schools then send an inventory of chemicals to be removed by our contractor. The Safety Seminar and removal are free.
The Safety Seminar presents: (1) Governmental regulations; (2) A model school safety program, K - 12; (3) Directions for teaching safety to students; (4) Suggestions for taking and maintaining an inventory of chemicals; (5) Correct chemical storage; (6) Cautions for demonstrations; (7) Instruction in microscale; (8) Articles on chemical safety by nationally known safety consultants; (9) Recommendations for selecting chemicals to discard.
We did a small pilot study of chemical removal without a safety seminar. In our experience, schools at which the chemistry teachers attend a safety seminar dispose of twice as much as schools in which only no one attends.
Deciding What to Keep
A national expert in toxicology gave a seminar last year and concluded the toxic level of most chemicals is unknown. Even so, a rating from mast hazardous, 4, to least hazardous, 1, of the chemicals commonly found in schools is provided. *It is difficult to make absolute statements about which chemicals may be used in teaching and which are too hazardous.
The first question a teacher should ask is , "Why do I need to use this chemical?" Then, "What are the hazards, and how can I minimize potential harm? Is there another chemical that can be used with less risk? Can this experiment be done in microscale?" If microscale is used the students will be exposed to tiny amounts, the amount purchased is much less and the amount of waste to dispose of is correspondingly small.
After visiting over a hundred schools in Ohio, it is evident that nearly all have chemicals they should dispose of. Even schools that have had chemicals removed recently may be unsafe because they feel they have solved their problems. They keep chemicals because the hazards of those chemicals are unknown to the teacher. In addition, improper storage of appropriate chemicals can cause harmful incidents.
In March of 1999, a shelf collapsed and bottles of concentrated nitric acid, acetic acid, and aqueous ammonia, broke, mixed and reacted. The fumes and damage were discovered and a hazardous clean up company employed. Correct storage would have prevented the mixing and need for a hazardous chemical team. School was cancelled for four days and the clean up cost was $150,000 for this Ohio school.
Getting Started
I noted earlier that it took ten years to accomplish the program in Ohio. I think other states can make use of our experience and do it in 2 or 3 years. NSELA can help by developing an awareness of he problem and the solution.
Information on this topic that could save you months of effort is available on our web site: http://www.summit.K12.oh.us/HWRP
Dr. Cliff Schrader is the Director of the Ohio Hazardous Waste Removal Program. He can be contacted at 1.800.968.0132 or by e-mail Cliffs@summit.k12.oh.us
LIVE LONG AND PROSPER WITH SAFETY!
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Dr. Ken Roy
K-12 Director of Science & Safety & authorized OSHA instructor
c/o Glastonbury Public Schools
Glastonbury, CT 06033-3099
Fax 860-652-7275
E-Mail: royk@glastonburyus.org
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