chapter 9 - a proven plan for eliminating dangerous ... · picric acid was originally used in...

CHAPTER 9 A PROVEN PLAN FOR ELIMINATING DANGEROUS CHEMICALS FROM SCHOOLS

J. CERLOVICH Iowa Department of Public Instruction, Des Moines, Iowa

197

9.1 INTRODUCTION

At the secondary educational level (grades 7- 14), the type of conducted in science classes and the selection and management of priate reagents constitute two of the most critical means of main safe learning environment. With increasing propensity of the public to tort liability suits when a wrong is perceived, teachers must protect selves by becoming better informed concerning the benefivrisk valu the chemicals selected for inclusion in their science cumculum.

According to Coble and Hounshell (I) ,

The questions science teachers should be evaluating relate not only to th alleged, or known, risk of the substance, but also to:

1. The perceived importance of the educational objective that the 1 tory exercise is designed to meet.

2. The existence (or nonexistence) of alternative ways of meeting the objective, or of chemicaI substitutes.

3. The method by which the exercise is to be conducted-whether as a hands-on student activity or as a teacher demonstration.

4. The maturity and/or “competence” of the students. 5. Environmental conditions within the laboratory (adequacy of ventila-

tion; l ~ r a t o r y design, including safety features; storage facilities; etc.).

In a 1961 survey of California chemistry teachers, Macomber reported that “several teachers finished their college chemistry courses with only vague ideas about the dangers involved in certain experiments or in the use of certain chemicals” (2). In 1974 two Paxton Center (Massachusetts) School 13-year-old girls were severely burned, as a result of misinterpre- tation of experimental procedures outlined in their textbook (3). The total suit involved $825,000. In 1975 a California high school student was injured in a chemistry laboratory when a chemical mixture exploded in his hands. Although the student had substituted potassium chlorate for potassium nitrate (specified by the textbook), he alleged that he had not been warned of the hazard of substitution. The student filed suit alleging teacher negligence in not providing instruction pertaining to chemical substitution. The court concluded that it is the teacher’s responsibility to

personally instruct students regarding selection, mingling, and use Of

ingredients in potentially dangerous mixtures, including instructions con- ceming chemical substitutes (4).

At *e Tenth Biennial ‘f

1. . . . that it (ACS) (

safety and health, i

istry departments V. side services for the

3. . . . to elementary a

tion to safety and hi 16. . . . to manufadun

catalogue listings a the contents.

It appears that steps vel of science teachers J

At least two specific qUeS

1. Which chemicals P!

2. Considering newb (EPA) regulations of certain substanc - - wen’ inability to stances; pressure I fices, and school k

in the secondary s( ----- - ~ --

-

1 Y

INTRODUCTION 199

In October 1979 a northern Iowa junior high school teacher experi- enced the symptoms of cardiac arrhythmia following a full teaching day conducting experiments in which nitrous oxide fumes were liberated in the laboratory. Since no exhaust hood was available, experiments were conducted on the window sill, with windows ajar. Following admission to the local hospital, the attending physician diagnosed nitrous oxide poison- ing due to cumulative effects (5).

During fall 1979 some long-forgotten picric acid (potential explosive chemical under certain conditions) was discovered on the shelves of many Pennsylvania schools. The overreaction of some officials touched off a series of repercussions in many other states. McDermott and Edgar reported that the whole episode could have been avoided if science teachers had heeded the repeated warnings to clean out storerooms and discard unwanted or unused chemicals (6).

At the Tenth Biennial Education Conference of the American Chemical Society (ACS) (October 1977) the participants recommended (7):

1. . . . that it (ACS) establish an adequately funded office of chemical safety and health, and that this office. . . . Provide academic chemistry departments with information about internal procedures and out- side services for the disposal of chemical wastes . . . . . . to elementary and secondary schools that they give greater attention to safety and health in their science courses . , . . . . to manufacturers and distributors of chemicals that they provide catalogue listings and labels that clearly indicate the hazard class of the contents.

13.

16.

turers' inability to retrieve and dispose of these hazardous substances; pressure by insurance companies, fire marshall's of- fices, and school boards to purge such chemicals f" storemms

200 A PROVEN PLAN FOR ELlMlNATlN

and the lack of pragmatic disposal techniques; how do loc schools remove such unwanted chemicals?

Many of the details of these questions are addressed in the plan ou below. The experience of one state indicated that there are no easy, answers. Through the cooperative efforts of all agencies responsible, ever, the problems can be addressed safely and effectively.

9.2

9.2.1

Picric acid was originally used in science classes to stain cell organell for microscopy work. As textbook science programs changed, better s

IOWA EXPERIENCE WITH PICRIC ACID

The Tip of the Iceberg

ing techniques and chemicals were introduced to teachers. Picric acid slowly fell into disuse. Over the years, without regular inventories and/or purging, the acid accumulated in the storerooms of many schools. As the chemical dried out, it became increasingly unstable.

In early April 1979, an article appeared prematurely in the Iowa State Superintendent’s Newsletter, Outreach, entitled “Picric Acid Means Dan- ger in School Lab” (8). The newsletter, which is mailed regularly to all Iowa educational institutions, created a series of repercussions. Many principals, superintendents, and classroom teachers immediately requested assistance in disposing of the acid. At that time, no convenient, effective mechanism existed to provide safe, practical, inexpensive, and expeditious disposal of the potential explosive. Manufacturers could not or would not retrieve suih small quantities of these chemicals because of transportation regulations, containers missing lot numbers, and diverse geographic distribution. In addition, the total magnitude of the problem, including quantity, physical state, and exact location of the substances was unknown.

In late April 1979, a chemical inventory entitled Assessment Inventory of Picric Acid in Iowa Schools (Table 9.1) was sent by the science consultant of the Iowa Department of Public Instruction (DPI) to all secondary schools (grades 7- 12) and community colleges to ascertain the magnitude of the problem. Teachers were instructed to note all forms of the picric acid in their inventories, including Cd-I,N,O,, ammonium picrate, 2,4,6-

J

__

EXPERIENCE WITH P i a

’? rABLE 9.1 Inventory Sheet

&ufwturer*s name and a$ Date of manufacture and/or container size Estimated amount in contai i d if dry) Concentration statements OJ

Any evidence of container i Building name: School address:

nitmphenol, picroniUi8 noltrinitrate. Indivih

wear protective gloves, 1 and to avoid unnecessw- requested of teachers inc dition, physical state of c

By May 1979, approx of 20 community college acid. The individual qua possessing the acid were

Since a great deal of tionally concerning the p more definitive guideline assist in the redistributiol

By mid-May 1979, a state agencies who cod( assembled by the State I

The agencies representec fice of Disaster Service$ ~

(DEQ) , University Hygil versity of Iowa, Chemica Science Safety Task Fb Public Instruction.

On confemng with c EPA , guidelines were de

~~

- --

SCHOOLS

local

outlined sy, quick de, how-

organelles :tter stain- ’icric acid ies and/or )Is. As the

Iowa State Ieans Dan- larly to all ms. Many diately re- :onvenient , znsive, and s could not because of

and diverse ie problem, stances was

nc ZnventorY :nce consul- 11 secondary e magnitude of the picric crate, 2 9 6

IOWA EXPERIENCE WITH PICRIC ACID 201

TABLE 9.1 Schools

h4anufacturer’s name and address (if available) Date of manufacture and/or lot number (if available) Container size Estimated amount in container (determine by visual inspection-do not remove lid if dry) Concentration statements on label (if any) Any evidence of container damage Building name: School address: City or town: Zip code:

Inventory Sheet Used to Assess Amounts of Picric Acid in Iowa

trinitrophenol, picronitric acid, carbazotic acid, nitroxanthic acid, and phenoltrinitrate. Individuals conducting the inventory were cautioned to wear protective gloves, laboratory aprons, and eye protective equipment and to avoid unnecessary, or rough, handling of containers. Information requested of teachers included chemical quantity, container type and con- dition, physical state of chemical, and age if known.

By May 1979, approximately 200 of Iowa’s 445 school districts and 6 of 20 community colleges reported the presence of various forms of picric acid. The individual quantities ranged from 1 ounce to 2 lb. The schools possessing the acid were widely dispersed across the state.

Since a great deal of ambiguous information was being circulated na- tionally concerning the properties and explosive potential of the material, more definitive guidelines had to be developed prior to asking teachers to assist in the redistribution or disposal operation.

By mid-May 1979, a 10-member, blue-ribbon committee representing state agencies who could provide applicable professional assistance was assembled by the State Science Consultant for the DPI in Des Moines. The agencies represented included: the State Fire Marshall’s Office, Of- fice of Disaster Services (ODs), Department of Environmental Quality (DEQ) , University Hygienic Lab, Environmental Health Services-Uni- versity of Iowa, Chemical Safety Committee-Iowa State University, Iowa Science Safety Task Force, Community Colleges, and Department of Public Instruction.

On conferring with chemical manufacturers, state chemists, and the EPA, guidelines were developed, to provide safe handling for local dis-

202 A PROVEN PLAN FOR ELIMINATING DANGEROUS CHEMICALS FROM SCHWu ” % .

posal of small quantities of the picric acid. Copies of the disposal insmc, tions were developed on the basis of testing at the University of Iowa. Large quantities of the acid, excessively dry batches, or containers of the acid from which lids could not be removed (after 48 hours of soaking in water), were removed from schools individually by the state fire ma- shall’s office, local sheriff‘s office, local fire department, or by the DEQ. In most cases, these containers of picric acid were remotely detonated in an environmentally approved landsite.

On May 10, 1979 and May 24, 1979, letters regarding picric acid stabilization and disposal were mailed to all secondary educational insti- tution administrators, who had identified the acid in their science storerooms, providing directions both for short-term stability and ultimate disposal. Instructions were based on the fact that picric acid normally contains 10-20% water for stability. The content of these letters is presented in Sections 9.2.2 and 9.2.3.

As of this publication all identified picric acid has been eliminated from local schools, without incident, by means of the above procedure or by the DEQ or the local fire marshall’s office.

9.2.2 letter 1 : Inventory of Picric Acid in Iowa Schools

Although picric acid is used predominantly in science classes, it may be utilized in art (staining glass) and crafts (tanning leather) classes also.

Picric acid normally contains IO-20% water for stabilizing. With the passage of time, such chemicals may become sufficiently dry to present potential explosive hazards. However, to date no such explosions have occurred without purposeful detonation.

In order to assess the quantities of picric acid presently in Iowa schools, and to initiate removal andlor dilution procedures the DPI is asking for your cooperation.

Things to Do: The following measures are recommended:

1. Avoid excessive movement or concussion of containers. 2. Carefully inventory your supplies (this is probably done regu-

larly each year).

1

3. Complete the attac sure to note all cc ammonium picrate bazotic acid, nitro)

4. Wear protective ch tection as a precau

5. Remove all oxidiz; kaloids from the in

6. Confirm that stora, access.

f Spills Occur. Absorb n mixture (90: 10 mixtu

UT local Department of 1

Things Not to Do. The fo

1. Do not open contair sugar). Tilt bottle. indicate a sufficient1

2. Do not attempt disp

3. Do not attempt dilu by chemical expert! future newsletters.)

9.2.3 letter 2: Picric AC

Following conferences with mental Quality (DEQ), Uni Marshall’s Office, Universil -- ~-

fice of Disaster Services, i enclosed guidelines were de

Picric acid normally con lowing instructions are p ~ l . creasing short-term potentia

:HOOLS

nstruc- Iowa. of the

king in e mar- DEQ .

ated in

ic acid il insti- ; store- xte dis- ontains nted in

:d from 2 or by

may be Is0 . Jith the present IS have

chools, Ling for

7egu-


3. Complete the attached questionnaire and return (Table 9.1). Be sure to note all compounds and derivatives of picric acid [i.e., ammonium picrate (2,4,6-trinitrophenol, picro-nitric acid, carbazotic acid, nitroxanthic acid)]. Wear protective chemical gloves, laboratory apron, and eye protection as a precaution against skin contact.

Remove all oxidizable materials, finely divided metals, and al- kaloids from the immediate vicinity of the picric acid.

6. Confirm that storage area is well ventilated and has restricted access.

4.

5.

If Spills Occur. Absorb materials with sodium bicarbonate or sand-soda ash mixture (9O:lO mixture). Store in covered glass container and call your local Department of Environmental Quality Spills Unit.

Things Not to Do. The following measures must not be undertaken:

1. Do not open container if picric acid is dry (similar to dry salt or sugar). Tilt bottle. If crystals roll over each other, this may indicate a sufficiently dry state to be hazardous.

2. Do not attempt disposal in any manner. 3. Do not attempt dilution until adequate information is provided

by chemical experts and manufacturers. (This will appear in future newsletters.)

9.2.3 letter 2: Picric Acid Stabilization

Following conferences with representatives of the Department of Environ- mental Quality (DEQ), University of Iowa Hygienics Lab, Iowa State Fire Marshall's Office, University of Iowa Environmental Health Service, Of- fice of Disaster Services, and the Iowa Science Safety Task Force, the enclosed guidelines were developed.

Picric acid normally contains 10-20% water for stabilizing. The following instructions are premised on increasing such stability while de- creasing short-term potential hazards.

I

,

204 A PROVEN PLAN FOR ELIMINATING DANGEROUS CHEMICALS FROM SCHWU~

Things To Do: The following measures are recommended:

1.

2.

3.

4.

5.

6 .

7.

8.

9.

10.

All preparations should be completed in a laboratory near a sink. Sand-soda ash mixture (10: 1) should be available in case of accidental spill (refer to April 20 letter). Wear rubber gloves, laboratory apron, and eye protection when handling the containers of picric acid. All bottles containing the picric acid should be handled gently and cautiously. Clean the external surface of the bottle by wiping with a damp cloth. Carefully invert the bottle of picric acid in a beaker, or similar glass container, filled with tap water (Figure 9.1).

Cover beaker with glass plate to help assure immersion of the bottle and to help reduce water evaporation. Clearly label the beaker: “PICRIC ACID-DO NOT DIS- TURB.”

Inform custodial staff not to tamper with this setup. Place the beaker on a shelf away from general access. Do not be concerned with possible gas bubbles or water discol- oration; these are both positive signs that water is entering the bottle and stabilizing the picric acid. Discolored water indicates that acid is entering the water. As this is a strong dye, do not allow contact with skin surface.

Glass weight

Tap water Bottle containing picric acid

Beaker Label

FIGURE 9.1 to enter and remove sensitivity to explosion by moistening the chemical.

Submersion of a bottle of picric acid in water. The inverted position allows water

f IOWA EXPERIENCE WITH PIC‘ -

spills. If a spill occurs or if there is a spill on mixture; place glass co\ unit.

Things Not to DO. Do - attempt disposal. This I preparing the container A

9.2.4 letter 3: Picric

General Discussion. Tl followed by discharge 1

presuppose that the pic water in accordance wit in a vessel that is easily

Some consideration t

solutions being discharg biological organisms of than 200 ppm (200 mg dilution will occur in tj treatment system. It is be less than 2000 ppm procedure described in I

If your school is not L has its own septic syste environmental authoritir

Useful Conversion facto disposal are as follow:

_- 1 pound = 1 pound = ~

The solubility limit of F

14,( 1

0.12 p

HOOLS

:ar a case

when

ently

iamp

milar

If the

DIS-

liscol- ng the licates do not

cric acid

allows water


Spills. If a spill occurs in the sink, flush with copious amounts of water, or if there is a spill on the counter or joor , cover with sand-soda ash mixture; place glass cover over spill. In both cases, call the DEQ Spills Unit.

Things Not to Do. Do not remove lid from picric acid bottle, and do not attempt disposal. This procedure will help assure stability in addition to preparing the container for further dilution procedures.

9.2.4 letter 3: Picric Acid Disposal for Iowa Schools

General Discussion. This disposal technique is essentially one of dilution followed by discharge to the sanitary sewer system. These instructions presuppose that the picric acid container has already been immersed in water in accordance with earlier instructions or that the acid is contained in a vessel that is easily opened.

Some consideration must be given to the concentration of picric acid solutions being discharged to the sanitary sewer. Picric acid is toxic to the biological organisms of a sewage treatment plant in concentrations greater than 200 ppm (200 mg/liter). It is safe to assume that at least a tenfold dilution will occur in the plumbing system of any metropolitan sewage treatment system. It is important, therefore, that the picric acid solution be less than 2000 ppm at the point of discharge (laboratory sink). The procedure described in the following paragraphs will ensure that.

Ifyour school is not connected to a municipal sewage system but rather has its own septic system, do not follow this procedure. Instead, contact environmental authorities for specific instructions.

Useful Conversion factors. disposal are as follow:

The units most commonly used in picric acid

1 pound = 16 ounces 1 pound = 454 g

1 ounce = 24.4g 1 gallon = 3.8 liters

The solubility limit of picric acid in water at 25°C (77°F) is:

14,000 ppm = 14,000 mg/liter = 14 @liter = 53.2 g/gallon =

0.12 pounds/liter = 0.44 pounds/gallon

I

Disposal. The following measures are recommended for picric acid dis. posal:

1 . Picric acid is a strong mordant dye. Wear rubber gloves and l a b ratory apron. Wear eye protection. Picric acid is also toxic by inhalation (of dust), skin absorption, and ingestion. Wash any accidentally exposed skin immediately with soap and water. In case of accidental eye contact, flush immediately with water for at least 15 minutes and consult a physician.

2. Remove the picric acid container from the beaker of water in which it had been immersed (see Sec. 9.2.3). Rinse the exterior of the bottle in the sink with copious amounts of cold tap water.

3. Inspect the water in the immersion container. The intensity of yellow coloration is directly proportional to the picric acid concentration. If the immersion container is glass, proceed to step 4. If not, transfer the water into a suitable clean glass beaker ( I liter or larger) and then proceed to step 4.

4. Carefully open the picric acid container. Note: If the bottle will not open with hand force, even after immersion in water, do not apply excessive force by rapping the lid or using tools. Instead, contact the DEQ spills unit for further instructions.

Slowly add the picric acid to the immersion water with gentle stirring using a glass rod. Continue additions until the solubility limit is approached. Do not apply heat to enhance solubility. Follow the table below to determine approximate amounts of picric acid to reach solubility limits.

5.

Container Volume Weight of Picric Acid

14 g I liter 1 liter 0.03 Ib 1 liter 0.5 ounces

1 gallon 53.2 g 1 gallon 0.12 Ib 1 gallon 1.8 ounces

Note: All table values are approximate. Remember that you don't know

initial percent water of the s mber also that immersior of water into the bottle b.

he picric acid to some exre- picric acid prior to its addic

6. Open the cold water tq Sharging at a rate of 10 Li: le: This discharge rate is 2

l&oratory water taps. If your i adjust the followhg steps asci flow increase.

I SCHOOLS

acid dis-

and labo- nhalation r exposed : contact, t a physi-

. in which bottle in

:ensity of entration. ansfer the n proceed

le will not Ay exces- )EQ spills

ith gentle ty limit is the table solubility

lon’t know


the initial percent water of the solid picric acid (it may be as high as 15%). Remember also that immersion of the picric bottle in water has allowed entry of water into the bottle by capillary action, thus allowing hydration of the picric acid to some extent. It is not necessary, therefore, to weigh the picric acid prior to its addition to the water.

6 . Open the cold water tap in the laboratory sink and verify that it is discharging at a rate of 10 liters/minute (2.6 gallons/minute) or more. Note: This discharge rate is assumed to be easily obtainable by most laboratory water taps. If your facility cannot attain this rate of discharge, adjust the following steps accordingly. Do not use hot water to obtain a flow increase.

7. Assuming your picric acid solution is at or near saturation, the acid concentration will be 10,000-14,000 ppm (at 25°C). With the cold water tap discharging at approximately 10 literdminute, slowly and evenly discharge one liter of saturated picric acid solution into the sink over a 2- minute period. Under these conditions, the average picric acid concentration in the sink drain will be 476-666 ppm (10,OOO-14,OOO mg of acid in 21 liters of water). Consider this to be a maximum discharge rate. Obviously, the slower the discharge rate of acid solution, the greater the dilution, the less probable the adverse impact on the sewage treatment plant. Feel free to lower the discharge rate of the acid and expand the dilution to the limits of practicality.

8. Continue by refilling the acid solution container with clean tap water and resuming additions of picric acid to that water until the solubility limit is again reached. Discharge this solution to the sink as in step 7. Repeat steps 7 and 8 until the entire supply of picric acid is depleted.

9. Wash all glassware and the sink with a mild bicarbonate solution, followed by a strong soap solution. Rinse with tap water, paying particular attention to removal of all splash residues on the laboratory counter and upper sink walls.

10. Dispose of the empty, rinsed, picric acid container in the trash. Glass-stoppered bottles can be returned to stock after thorough washing.

Finally, it is recommended that this disposal be done during peak flow to the sewage treatment plant, which in most cases is early morning (8:00-9:00 A.M.).

.

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