Disposal of Chemical Waste

Segregation of regular waste from hazardous laboratory waste is essential

Regular waste pertains to waste devoid of chemical, biological, or radioactive content.
Regular waste should be placed in designated trash bins, which will then be taken out of the laboratory by cleaning personnel.

Avoid placing sharp items like broken glass, Pasteur pipettes, syringes, or any potentially harmful materials in regular trash bins. Dispose of sharp objects in a specialized rigid plastic container known as a "sharps" container.

Chemical waste is transported to a specified section within the department that follows proper control measures. Do not leave chemical waste within the laboratory premises or in shared spaces like corridors, equipment rooms, or temperature-controlled chambers.

Empty containers are collected separately from hazardous waste and stored in a dedicated area designed for this purpose.

Chemical Waste Management Guide

  1. Ensure waste disposal is carried out following the chemical compatibility groups guidelines.
  2. Empty chemical liquids into assigned collection containers labeled with appropriate waste stickers, complete necessary details, and proceed to the waste collection area.
    As a standard practice, chemical waste should be discarded in containers of the same material as those in which they were received. For instance, a chemical substance that arrived in a glass container should be disposed of in a glass container. Similarly, chemicals received in plastic containers should be discarded in containers of the same plastic type (such as polypropylene, polystyrene, HDPE etc.). It's crucial to confirm that the chemical won't cause the container to dissolve.
    For instance, Chloroform and Xylene must be separately placed in glass containers since they can melt plastic containers, such as medium containers that have been rinsed. In contrast, Hydrofluoric acid (HF) and NaOH solution should be separately placed in HDPE (High Density Polyethylene) containers since they react with glass.
  3. Allow dishes with residual volatile chemical liquids to remain within the chemical fume hood (once emptied) until the liquid remnants have completely evaporated. Once evaporation is complete, plastic utensils (which are biodegradable) can be placed into a regular waste bin. Glassware (non-biodegradable) should be washed for future use.
  4. Dispose of contaminated plastic utensils (bearing non-volatile chemical residues) in a specified waste container or a chemical waste bag (biohazard waste bag). Apply an appropriate label to the bag/container and proceed to the waste collection area.
  5. Dispose of biodegradable sharp waste (including needles, glass pipettes, etc.) into a designated sharp bin container.

General Highlights

  1. Students and staff are accountable for transporting chemical waste to the designated waste collection point within their department or floor.
  2. Exercise caution when segregating compatible chemicals (refer to the link provided) to prevent potential chemical reactions. It is permissible to combine multiple compatible chemicals within a single container. If there are any uncertainties regarding compatibility, it is advised to keep the chemicals separate.
  3. Chemical waste containers should be marked appropriate labels. Utilize the dedicated Weizmann Net application to access suitable labels for the specific chemicals being disposed. It is imperative to clearly inscribe the substance's full name (without abbreviations), its concentration, the department's name, room number, and the contact number of the waste responsible individual in the lab.
  4. Refrain from disposing of chemical waste into lab equipment like Erlenmeyer flasks, test tubes or chemical beakers. Utilize plastic containers with capacities ranging from 100 ml to 5 liters or glass bottles (based on the material being discarded) and ensure that the vessel is filled no more than 80% of its capacity

Ethidium bromide waste

Ethidium bromide up to a concentration of 1ug/ml is considered as a non-hazardous chemical. Those Solutions can be discarded into the sink. Likewise, gels disposed into regular waste bins. However, when working with more concentrated solutions exceeding 1ug/ml, it's still necessary to follow the "tea bag" disposal procedure. (Details in the safety unit). 

It's important to note that gloves that encounter gels, running solutions, sample-loading tips, diapers, and wet surfaces resulting from running solutions (such as on the UV table or floor) should be disposed of in regular waste bins due to their minimal ethidium bromide content.

Empty dripping bottles that contained ethidium bromide up to 1mg/ml will be disposed into regular waste bins.