Decontamination of Infectious Wastes

Infectious Wastes What are infectious wastes?? –Depends on whose regulations your situation falls under Regulatory Authority for Infectious Wastes –EPA (RCRA, MWT, CAA) –OSHA (OSHAct; sharps, BBP) –DOT (inter- and intrastate transport) –CDC (Biosafety Guidelines w/NIH) –States

Professional Organizations Joint Commission on Accreditation of Health Care Organizations (JCAHO) National Committee for Clinical Laboratory Standards (NCCLS) Hospital Infection Control Practices Advisory Committee (HICPAC) American Biosafety Association (ABSA)

Thermal Inactivation Factors affecting heat resistance of microbes: –Age –Growth Phase –Growth Temperature –Sublethal Heating –Nutrient Conditions –pH –Antibiotics –Cation Exchange Other treatments affecting heat resistance: –Hydrostatic Pressures –Ionizing Radiation –Chemical Treatment (e.g. hydrogen peroxide) –Other Substances

Thermal Inactivation Factors Affecting Dry Heat Destruction –Temperature –Microbial Water Content –Control of Water Content During Heating –Encapsulation in Crystals and Solids –Gas Atmosphere –Added Solutes –Lipids

Traditional Waste Treatment and Disposal Incineration –2400 MW incinerators in operation –846,000 toms of MW –Reduce to non-combustible ash ( ºC; 1093ºC) Autoclaving –Laboratory: 121ºC at 15psi for 30 minutes –Commercial: 135ºC at psi for 1 hour

Alternative Treatment Processes Thermal Processes –Rotoclav (144ºC at 48 psi for 65 minutes) –Sani-Pak Sterilizers (32 psi, 132ºC then ºC; 30 minutes) –Chemi-Clav (continuous feed; sodium hypochlorite and water; ºC for 30 minutes) –Microwave Treatment (1.2 kW; ºC for 30 minutes) –Electro-Thermal Deactivation (ETD) (low-frequency radiowaves used to heat 93ºC –Bio-oxidation/pyrolysis (93-538ºC then ºC) –Plasma Pyrolysis (electrically charged gas; same results as incineration but no emissions problems)

Alternative Waste Treatment Processes Chemical Processes –Peracetic acid (Ecocycle 10) –Degradables Processing (Polyvinyl alcohol products; Orex DP2000; 82-95ºC) –Alkaline Hydrolysis (WR2 Tissue Digestor; ºC at psi for 3-18 hours) Irradiation –E-beams

Microwave Shredding Treatment

Chemi-Clav

Alkaline Hydrolysis

Air Incineration

Bio-Oxidation/Pyrolysis