Safe Hazardous Waste Disposal: A Comprehensive Overview

Defining Hazardous Waste

Hazardous waste (HW) is defined as waste with intrinsic chemical and physical characteristics like toxicity, ignitability, reactivity, and corrosivity (Kumar et al., 2023). These characteristics can pose substantial danger to people or the environment (Kumar et al., 2023).

Key Characteristics:

• Toxicity: Capable of causing harm to living organisms.
• Ignitability: Easily combustible or flammable.
• Reactivity: Unstable and prone to violent reactions or explosions.
• Corrosivity: Able to dissolve or destroy materials, including living tissue.

The EPA (Environmental Protection Agency) maintains a Toxics Release Inventory (TRI) database listing over 600 potentially hazardous chemicals (Kumar et al., 2023).

Risk Evaluation and Management

Importance of Risk Evaluation

Proper risk evaluation of hazardous waste inventory is crucial for safe operation, especially given limited disposal capacity (Deng et al., 2020). Risk management is essential to prevent environmental pollution and disasters (Deng et al., 2020).

Risk Evaluation System

A risk evaluation system should consider:

• Equipment
• Management Level
• Nature of Hazardous Waste
• Operations (Deng et al., 2020)

Methodologies for Risk Evaluation

• BWM-TOPSIS Hybrid Method: Used to evaluate safety risks associated with hazardous waste inventory (Deng et al., 2020).

Inventory Management

Effective inventory management is vital, considering hazardous waste is often worthless but cannot be discarded at will (Deng et al., 2020).

Safe Disposal Methods and Strategies

Waste Management Hierarchy

Prioritize waste management strategies based on sustainability:

1. Reduction: Minimizing waste generation at the source (Orazov et al., 2024).
2. Reuse: Employing items for their original purpose or repurposing them (Orazov et al., 2024).
3. Recycling: Processing waste materials into new products (Kumar et al., 2023).
4. Treatment: Altering the chemical or physical characteristics of waste to reduce its hazard (Srivastava, 2024).
5. Disposal: Safely containing waste in landfills or through incineration (Kumar et al., 2023).

Common Disposal Techniques

• Landfilling:
  • Most common disposal method, but can lead to leachate and VOC emissions (Kumar et al., 2023).
  • Leachate can contaminate groundwater (Kumar et al., 2023).
• Incineration:
  • Reduces waste volume but can release toxic gases (Kumar et al., 2023).
  • Requires careful management of emissions and incinerator leachate (Kumar et al., 2023).
• Recycling:
  • Sustainable strategy to minimize harmful impacts (Kumar et al., 2023).
  • Allows for the reuse of materials (Kumar et al., 2023).
• Chemical Treatment:
  • Using chemical reactions to detoxify or neutralize hazardous waste (Srivastava, 2024).

Medical Waste Management

• Labeling: Proper labeling of containers with hazard symbols (Srivastava, 2024).
• Disinfection: Using sodium hypochlorite for disinfection (Srivastava, 2024).
• Mutilation/Shredding: Reducing environmental risks by mutilating or shredding waste (Srivastava, 2024).

Sustainable Hazardous Waste Management

• Aim for a circular economy approach (Kumar et al., 2023).
• Combine waste management strategies based on toxicity levels (Kumar et al., 2023).

Regulatory Framework and Compliance

International Agreements

• Relevant international agreements regulate the flow of hazardous waste across borders (Wilson et al., 2024).

European Regulations

• Waste is defined as hazardous if it satisfies at least one of the 15 hazard properties (HP) (Beggio et al., 2021).
• Wastes are classified as hazardous according to the 6-digits codes enlisted in the European Waste Catalog (Beggio et al., 2021).

Direct vs. Indirect Approach

• Indirect Approach: Assigning HPs from the total content of hazardous substances (Beggio et al., 2021).
• Direct Approach: Relies on outcomes of single HP-specific laboratory tests (Beggio et al., 2021).
• European legislation affirms that direct test results will prevail over the results from chemical composition analyses (Beggio et al., 2021).

Case Studies and Examples

ETUT's Zero Waste Program

• Oguz Han Engineering and Technology University of Turkmenistan (ETUT) implements a Zero Waste Program (Orazov et al., 2024).
• Strategies include educational campaigns, eco-friendly purchasing, and collaboration with vendors (Orazov et al., 2024).
• Employs structured waste categorization and centralized repositories (Orazov et al., 2024).
• Manages hazardous waste from laboratories with local authorities (Orazov et al., 2024).

District General Hospital, Hambantota

• Implemented waste management interventions to reduce waste production (Ubeysekara et al., 2024).
• Waste production per bed per day was significantly reduced (Ubeysekara et al., 2024).

Challenges and Future Directions

Limited Disposal Capacity

• The disposal capacity of hazardous waste is often far behind the amount of hazardous waste generated (Deng et al., 2020).

Need for Improved Technologies

• Adopting new technologies in hospital waste management is essential (Khaled & Ali, 2023).

Addressing Public Health Concerns

• Effective biomedical waste treatment is crucial for safe ecosystems and healthy populations (Anam et al., 2024).