Page 241 - Demo

“Your Safer Source for Science”
Chemical Disposal Procedures
239
Laboratory Chemical Disposal
• General guidelines
• Chemical disposal procedures • Biological disposal procedures
The Basics of Laboratory Chemical Disposal
Before You Undertake Any Disposal Procedure— Please Read this Narrative!
Chemical disposal is a routine part of laboratory science programs. Most lab activities will generate some leftover chemicals, solutions, and chemical byproducts that will require proper disposal. Advance planning and preparation will help you minimize the amount of hazardous waste generated and reduce the time and resources needed to dispose of excess nonhazardous chemicals or chemical byproducts.
Every school should have a Chemical Hygiene Plan that outlines appropriate policies and procedures for disposing of laboratory chemi- cal byproducts and correctly identifying hazardous waste requiring licensed disposal. The first step in any laboratory waste policy should attack the problem at its source—where and when waste is generated. Careful planning, tailoring lab activities to clear curriculum objectives, adopting microscale lab techniques, and substituting safer chemicals will help you reduce the amount of waste generated. (See the article “16 Steps to Minimize Chemical Disposal” on page 236.)
Laboratory chemical disposal requires specific knowledge and proce- dures. Knowing the type of sewer system your school has and understanding all federal, state, and local regulations that may apply are important steps in laboratory chemical disposal. Before you choose a disposal method, it is absolutely essential that you review your plans with regulatory officials. Do not assume that because we publish a set of disposal methods, these methods are “approved” or have the “bless- ing” of regulatory officials—NOT SO! In publishing laboratory waste disposal methods, we assume that:
 You will consult with local regulatory officials before proceeding.
 You will act responsibly with respect to all regulations.
 The quantity of material involved is very small (i.e., laboratory quantities).
 Only trained personnel will attempt the methods.
DO NOT USE THESE METHODS if the methods do not meet local regulations, if the quantity of material is not small, or if you are not comfortable with a disposal procedure.
Advance knowledge, preparation, and planning will also allow you to dispose of laboratory waste safely and effectively. There are three main categories of laboratory waste generated:
 Biological or biomedical waste (preserved materials, “live” mate- rial remains, culture products).
 Chemical waste (unused testing solutions, reaction products, stains and indicators).
 Hazardous waste requiring licensed disposal.
Biological Waste
Biological science experiments may produce hazardous waste. Special attention should be paid to all microbiological culture products since they may contain harmful organisms. Preserved materials, deceased living materials, and all “sharps” also deserve special attention prior to disposal. To assist with handling biological wastes, Flinn Scientific has developed a biological waste disposal procedure. Please review pages 259–260 for a thorough discussion and detailed procedures for the safe disposal of of biological waste materials.
Chemical Waste from Laboratory Experiments
Before performing any laboratory activity, review the properties of the chemicals required and any products that may be generated. If the reactants or products present unique hazards or will require specialized disposal (e.g., flammable organic solvents), consider modifying the experiment or finding a different experiment that will teach the same concept. Flinn Scientific maintains an extensive library of tested laboratory activities. Please call (1-800-452-1261) or email us ([email protected]) for suggestions of safe laboratory activities.
The catalog entry for every chemical listed in the Chemicals section of this Flinn Scientific Catalog/Reference Manual includes a Flinn Suggested Disposal Method number in the product description. Simply look up the product in the alphabetical section of the chemical list- ings and determine the disposal number. Then refer to this Suggested Disposal Method in this Reference section.
For best results, incorporate treatment of leftover chemicals and reaction byproducts into any laboratory activity involving chemi- cals. Collect all solutions or similar products in a centrally located container. For example, if students are working with acidic solutions having a pH <2, have them pour their products into one beaker placed in the hood or other central location. The acid solution may then be neutralized with base according to Flinn Suggested Disposal Method #24b at the end of the lab period. Making disposal a routine part of every lab activity teaches students that concern for the environment is everyone’s responsibility and that scientists working in the lab also take this responsibility seriously.
Inventory Management and
Laboratory Chemical Disposal
Chemicals, supplies, and equipment tend to accumulate in the science department over time and can lead to hazardous situations. Effectively managing the chemical inventory in the school will help you reduce the amount of chemical waste and the potential impact of waste disposal on your school’s budget and resources. The chemical store- room should be cleaned out on a regular basis. Before you undertake chemical cleanout and disposal, enlist the active consent and participa- tion of school or district administrators and facilities or risk managers to provide adequate resources. Hasty responses to chemical disposal are often expensive, unsafe or harmful to the environment.
Inspecting and Preparing the Inventory
Carry out a preliminary inspection to determine if cleanout and disposal are warranted. Look for the following:
• Bottles and containers that are broken, corroded or have crystals growing around the caps or liquid seeping out of closures.
• Inappropriate storage containers such as beakers and flasks, buckets, plastic soda bottles or food jars.
• Poorly labeled containers used for storing solutions or transferring chemicals. Labels must have the chemical name, concentration, date, and appropriate hazard information and warnings.
Prepare or update the annual chemical inventory and identify chemi-
cals you want to keep. Laboratory chemicals and preserved materials that are no longer part of the curriculum should be removed, as should chemicals that are dangerously toxic, potentially explosive, contami- nated or decomposed, mislabeled, out-of-date or present in surplus amounts. Assemble a list of chemicals requiring disposal. Include the
THE BASICS OF LABORATORY CHEMICAL DISPOSAL continued on next page.