If location of the facility is within an urban

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1 INFECTIOUS WASTE MANAGEMENT Debra L. Hunt, Dr.P.H. Environmental Safety Duke University Medical Center, Durham, NC In developing an infectious waste management program for a hospital or other institution, one must realize that there is no one optimum plan. Regulations and/or recommendations must be interpreted by each facility in order to design a safe and effective plan for the handling and disposal of infectious waste at each location and type of facility. The purpose of this presentation is to review the elements within the Environmental Protection Agency "Guidelines for Infectious Waste Management" as well as the North Carolina regulations, and to discuss the various options and interpretations. Several variables should be considered before developing the specific elements of an infectious waste management program: 1. Zocat ion. The proximity of the facility to other hospitals, institutions, or commercial treatment facilities will influence the decision to treat waste off-site or to share treatment processes (i.e., a common incinerator). If location of the facility is within an urban area, public reaction to the management policy will also need to be considered. 2. The funds available for managing infectious waste will, of course, be a prevailing factor in determining cost-effective alternatives. Variables considered will include personnel, maintenance costs, service fees, hauling fees, and annual operation of waste disposal eqiuipment.

2 34 3. Available eauidment. The decision to treat waste on-site vs off-site will largely depend on what treatment equipment is available. One advantage to use of on-site equipment is that the single generator of infectious waste maintains control of the waste until it is rendered non-infectious. Since this reduces the risk for workers outside the facility, on-site treatment offers a liability advantage. In addition, many hospitals already have autoclaves available in laboratories or incinerators in pathology. The use of readily available off-site equipment (commercial treatment facilities or shared equipment with other institutions) can be the most cost-effective alternative if personnel costs or initial purchases of large treatment equipment are considered. However, if offsite treatment is used, proper processing of the waste by the outside facility must be insured,. 4. Ouantitv and nature of infectious waste eenerated. - The type and size of the institution must be considered. For example, does the institution deal primarily with animal research? Are there large quantities of needles used? the primary treatment method. If so, an incinerator may be justified as If the institution deals primarily in microbiological research, an autoclave will be adequate. 5. Reeulatorv constraints, Several agencies affect and even regulate the types of treatment and/or disposal methods for infectious waste (see Table 1). Local sewage authorities, state regulations, and federal guidelines will all impact on management decision. Locally, the county or municipal authorities may present the most restrictive requirements. For example, in New York City on August 2, 1985, Mayor

3 35 Koch signed into law the requirement that all laboratory, isolation, sharps, and surgical wastes be incinerated before acceptance into a New York City landfill (1). On July 1, 1985, the North Carolina legislature passed a law dictating that infectious waste must be treated by an approved method prior to disposal in a state landfill (2). The contents and interpretations will be discussed in more detail throughout this presentation. In May 1986, the EPA published revised guidelines for infectious waste management (3). While the EPA Guidelines are meant to be used as a reference manual and not as a set of regulations, it is possible that they may be regarded as "community standards" from a liability standpoint. These Guidelines probably represent the most detailed recommendations to date, and will also be discussed in more detail. The Centers for Disease Control (CDC) recommendations identify specific infective material from patients on infectious disease isolation (4). and are referenced in the EPA Guidelines. The Joint Commission on Accreditation of Hospitals (JCAH) also offers recommendations for handling infectious waste in hospitals (5), but these are the least restrictive of all the agencies' recommendations. These five variables listed above are the prevailing restrictions that must be confronted when designing an infectious waste management plan. Each institution must review its own unique set of variables in terms of the interpretations of the agencies' guidelines and regulations.

4 36 Table 1. Agencies Which May Regulate or Affect Infectious Waste Management Local (county, municipal) State - 10 NCAC 10G, Solid Waste Management, July 1, 1985 Solid and Hazardous Waste Management Branch Division of Health Services Department of Human Resources P.O. Box 2091 Raleigh, N.C (919) Environmental Protection Agency Guidelines - May, 1986 National Technical Information Services Springfield, Va. Order #PB EPA Document #EPA/530-SW (704) Centers for Disease Control - Guideline for Handwashing and Hospital Environmental Control, 1985, Section 4: Infective Waste Joint Commission on Accreditation of Hospitals

5 37 Elements of an Infectious Waste Management Plan The following are the important elements that must be defined in order to develop an effective, safe, infectious waste management policy. They are outlined in the EPA Guidelines, but are discussed here in light of existing NC state regulations. 1. Definition of Infectious Waste. In both the EPA Guidelines and the state regulations, infectious waste is defined as "...waste capable of producing an infectious disease" (2, 3). The statement is a rather broad one, but lays the foundation for decisions that must be made in defining infectious waste within certain llgray" areas within the institution. Note that neither definition states that waste "contaminated" with organisms is considered infectious. Rather, the waste must be capable of initiating an infectious disease. 2. TvDes of Inf ectious Waste. The EPA and the state of North Carolina have designated categories of waste that each considers infectious. A comparison of the two indicates that they are similar in their designations (Table 2). There are'some major differences, however, that will influence the amount of waste considered infectious as well as the methods used for treatment. Ultimately, these have a large impact on the cost of implementation of the waste management plan. The most distinguishable difference between the two is the absence of isolation waste (i.e., waste from patients placed on infectious disease isolation) from the NC state regulations and its inclusion in the EPA categories. Isolation waste is handled in a more contained

6 38 Table 2. Categories of Infectious Waste Environmental Protection Aeencv North Carolina Isolation Wastes Cultures & Stocks Human Blood/Products Pathological Waste Microbiological Waste Blood/Products (Bulk) Pathological Waste (human and contaminated animal) Contaminated Animal Carcasses, Body Parts, and Bedding Contaminated Sharps Sharps Miscellaneous

7 39 manner within hospitals if CDC isolation precautions are followed. However, in the state of North Carolina, this category of waste need not be treated prior to disposal in a landfill. While both agencies categorize blood and blood products as infectious waste, the NC regulations specify "bulk" blood. This definition allows an area of interpretation for each hospital. For example, Duke Medical Center sets a quantity of 20 milliliters or above to denote "bulk" blood, primarily to exclude the small quantities of blood that might be contained in vacutainer tubes. The third difference noted in the categorization of infectious waste is that the EPA has included a miscellaneous category in its Guidelines that includes the following types of waste: o surgery and autopsy wastes (soiled dressings, sponges, etc.) o miscellaneous laboratory wastes (used specimen containers, parafilm, slides, etc.) o dialysis unit wastes (tubing, filters, etc.) o contaminated equipment (disposable equipment used in patient care) The NC regulations include "human tissues, organs, body parts, secretions and excretions, blood and body fluids that are removed during surgery and autopsies" under the classification of pathological waste,. and, therefore, require them to be handled as infectious waste. The regulations, however, do not include materials "contaminated" by the above wastes (soiled dressings, sponges, etc.)

8 40 The EPA leaves the final determination of infectious waste to the individual institution. A designated, responsible person must make the decision regarding the infectious nature of the above wastes based on a rational and logistical approach. For example, surgery waste originating from septic cases might be handled as infectious, whereas that from aseptic cases might be handled as routine trash. The designation of the types of infectious waste will be one of the more important decisions for an infectious waste manager. It will determine the extent of the problem, the treatment method chosen, the cost of the program, and the liabilities involved. 3. Handline of Infectious Waste, Once the difficult decisions regarding infectious waste designation have been made, the "nuts and bolts" of the operation can be established. First, it may be useful to determine a rough estimate of the quantity of infectious waste that the hospital generates. The amount that needs special processing will, of course, effect the type of treatment, transport, and storage of the waste, and, ultimately, the cost of the program. Rutala and Sarubbi (6), in a survey of hospitals in North Carolina, estimated that an average of lb of solid waste per patient per day was generated (11.85 to lb depending on hospital size). They also determined that "infectious waste" in this study comprised 10.9% of the total solid waste generated. Using Duke Hospital as an example, the following estimate can be made:

9 41 Amount of Solid Waste: 15 lb./patient/day x 1,000 patients = 15,000 lb/day Solid Waste Amount of Infectious Waste: 15,000 lb/day x 10.9% = 1,635 lb/day Infectious Waste Wallace et al. (7) have shown that different areas in an institution generate different quantities of solid waste. For example, the heavy.care units (ICUs, operating room) produce twice as much waste as support areas such as administration or pharmacy. They developed a table of formulas that allows calculation of waste quantity generated by these various units (Table 3). Calculation of the quantity of infectious waste might be further modified, depending on designations of infectious waste from each of the areas. The calculations are further complicated by estimation of the quantities of the ttes of infectious waste (e.g., sharps, microbiological, blood). Preliminary audits, surveys, and actual daily logs will provide this additional data, and will be more accurate than using a general formula. A. Segregation. The first procedure in an infectious waste management program will be the actual physical separation of the. infectious waste from general trash at the point of generation.

10 42 Table 3. Quantity of Solid Wastes Areas Light Care Units - (Psychiatric, ENT, Gen Med) Heavy Care Units - (Surgery, Cardiovcascular, Burn, ICUs, OR) Support Units - (Admin., Laundry) Special Units: x-ray, ER. Laboratories Kitchen Ouantitv (lb/dav) 2.77 number paid staff 4.47 number paid staff 2.21 number paid staff 0.48 number pts treated/day 0.19 number tests run or patients treated/day 1.5 number meals served/day

11 43 Segregation is useful not only to insure that the infectious waste is identified for proper treatment or handling, but to reduce the cost of special handling that might be applied to non-infectious waste. The infectious waste should be contained in clearly marked bags or receptacles such as a red bag or a container marked with a biohazard symbol. Infectious waste that also contains other recognized hazards (i.e., antineoplastics, radioactive materials) should be further separated and handled according to the federal or state regulations regarding these hazards. B. Packaging. More than any other element in an infectious waste management program, packaging of the waste becomes the most effective means of protecting the personnel who must deal with the waste from the point of generation to final disposal. Although infectious waste has not been shown to be a hazard for the general environment, documented occupational infections have occurred when an infectious waste has been improperly packaged for disposal. Needlesticks and cuts from sharp instruments that have been improperly handled or disposed have been a major mode of transmission of hepatitis B in health care personnel for decades. Therefore, integrity of the packaging of infectious waste should persist through all steps of the program - transport, storage, and treatment. Several factors that effect packaging should be considered: o Waste type. Liquids should be contained in capped bottles, solids in appropriate bags, and needles in puncture- resistant, rigid containers.

12 1 44 o Handling and transport. If transporting waste for long distances, plastic bags should be placed in boxes to insure their integrity. Infectious waste should not be compacted before treatment since this might effect the integrity of the containers and actualy disperse the waste. If transporting microbiological waste before treatment, specific packaging requirements by the CDC and Department of Transportation (DOT) must be considered. o Special considerations. Again, containers of infectious waste need to be marked in some manner for identification. Besides color coding and biohazard designations, some bags are available that have special tape or markings that change color or disappear/appear after treatment. Not only are these bags useful for identification of infectious waste, but they also assist in quality assurance of the program., C. Storage. If same day treatment for infectious waste cannot be obtained, storage of the waste should be addressed in the management program. The following factors will effect adequate storage: o Integrity of packaging. A recurring factor, integrity of the containers should also insure that no rodents or vermin are able to penetrate during storage. o Temperature and time. Some states place restrictions on storage time and temperature. For example, California permits storage for a maximum of four days at temperatures

13 45 greater than 32F. North Carolina regulations, however, do not address this issue. The EPA broadly recommends that storage times "be kept as short as possible" ( 3). o Location and design. The storage area should be specifically designated as such with limited access, In addition, the area should be well marked, as with a biohazard symbol. D. Transport. Safe transport of infectious waste should be.insured not only within the institution, but also if shipping off-site for treatment. Several factors to address include: o Proper packaging. As previously mentioned, rigid or semirigid leak-proof containers need to be used for off-site transport for treatment. Also, CDC and DOT packaging requirements need to be maintained. o Safe in-house transfer. To avoid dispersal of infectious material throughout the institution, trash chutes should not be used for transport. Rather, carts are recommended for transport in-house. Carts or vehicles used for in-house transport should be frequently disinfected. E. Treatment, The EPA notes that potential hazards resulting from - infectious waste are those that may occur when package integrity is compromised and infectious material is dispersed. The EPA, therefore,

14 46 recommends that infectious waste be treated before disposal in order to insure protection from these potential hazards. The NC regulations require that those wastes designated as infectious be treated and rendered non-infectious before disposal at a landfill. Treatment is defined by EPA as "any method, technique, or process designed to change the biological character or composition of waste... Treatment must reduce or eliminate pathogens (present in the waste) so that it no longer poses a hazard to persons who may be exposed to it." (3) Several optional means of treatment are recommended by the EPA as well as the NC regulations. The treatment(s) selected for an infectious waste management program will probably constitute the majority of the costs and liabilities of the program. For these reasons, several important factors need to be considered: o Use of recommended treatment techniques. Using recommended treatment techniques for infectious waste is desired because of proven efficacy and for liability purposes. The following techniques are recommended by the EPA: (1) Steam Sterilization. Use: Recommended for treatment by the EPA of all waste except pathological and animal bedding.

15 I 47 Advantages Disadvantages - availability; most facilities have autoclaves - no initial expense - inexpensive to run and monitor - easy to operate - time consuming - small quantities only - no reduction of waste volume (2) Incineration. Use: Recommended for treatment of all waste types by EPA and NC Advantage s Disadvantages - up to 95% reduction in waste volume - burning of non-regulated - pathological incinerators chemicals or plastics available in most hospitals require capability of - usable energy may be generated heat > 1,088F (heat recovery) - must meet federal, state, and local air pollution standards - expensive initial investment and high maintenance costs - requires trained personnel to operate

16 (3) Thermal Inactivation. Use: Recommended by EPA for microbiological cultures, generally large volume liquids of known pathogens (industrial). (4) GaS/VaDOr Sterilization (formaldehyde and ethylene oxide). Use: Formaldehyde may be used for certain items such as HEPA filters from biological safety cabinets. Advantages Disadvantages - effective - both are potential human - ET0 commonly used as a sterilant carcinogens - requires highly trained personnel (5) Chemical Disinfection. (Discussed in another chapter.) Use: Recommended by EPA for disinfection of contaminated equipment, liquid waste, and bloodfiody fluids. Advantages Disadvantages - effective if properly used - inexpensive - available - increases volume for disposal - residue must comply with local sewer restrictions

17 49 (6) Ionizing Irradiation. Use: Effective means of treatment for all infectious material except body parts (does not render unrecognizable) Advantages Disadvantages - effective - high initial cost - requires highly trained p e r s onne 1 - requires large space - problem of ultimate disposal of radiation source As implied above, different treatment methods may have specific applications for certain types of infectious waste. The EPA Guidelines and NC regulations each specify recommended treatment techniques for the various categories of infectious waste (Tables 4 and 5). Both agencies recommend incineration as a means of treatment for all types of infectious waste. The EPA recommends steam sterilization for practically all waste types except for animal bedding. For aesthetic reasons, both EPA and NC recommend that pathological waste such as body parts be rendered unrecognizable before disposal in a landfill. Therefore, steam sterilization is an adequate method of treatment for - the infectious nature of pathological waste, but this waste must be ground up and discharged to the sewer.

18 Table 4. Recommended Techniques for Treatment of Infectious Waste I Type of Steam Incineration Thermal Chem Other Infectious Steril. Inactiv. Disinf. Waste Isolation Waste Cultures & Stocks (Microbiological) Human Blood/ Blood Products (sewer) Pathological Wastes (mortician) Sharps Contaminated Animal carcasses Parts, Bedding

19 51 Table 5. Recommended Techniques for Treatment of Infectious Waste Type of Steam Incineration Other Infectious Waste Sterilization Microbiological Wastes Human Blood/ Blood Products (Bulk) Pathological Wastes Sharps Contaminated Animal Carcasses and Parts (sewer) (hardwalled container)

20 52 Unlike the EPA Guidelines, the NC regulations do not specifically recommend steam sterilization as a treatment technique for bulk blood or sharps. Instead, bulk blood must be either incinerated or discharged to the sewer (contingent on local sewer restrictions). Sharps must be either incinerated or mutilated, presumably to render needles inoperable and to interrupt their mode of transmission of infectious diseases. Note: Effective November 1, 1987, a new NC statute (G.S A) prohibits mutilation of needles and syringes as a means of treatment. Rather, sharps should now be placed unbroken in either an incinerator or in a hardwalled container and disposed of in a sanitary landfill. This.statute is consistent with the CDC's "Recommendations for Prevention of HIV Transmission in Health-Care Settings" (August 21, 1987; MMWR, vol. 36, No. 2s). It must be noted that although EPA and NC recommend specific treatment methods, both agencies recognize that other technologies might be available for effective treatment of infectious waste. If an institution chooses an alternative method of treatment, the EPA recommends that it must demonstrate that the method is effective before use, and biological testing schedules should be developed for monitoring the treatment process. NC regulations, likewise, will approve alternative methods "upon determination that the method effectively renders infectious waste non-infectious." (2). o Establish standard operating prodecures. For whatever treatment process is selected, the institution must be familiar with its limitations, such as maximum temperature, waste feed rate, and time required for optimum treatment.

21 53 o Monitoring. The EPA further recommends that each process be monitored, perhaps as part of a quality control protocol. For example, the US Pharmacopeia recommends the use of biological indicators for monitoring treatment processes such as steam sterilization, incineration, and thermal inactivation (8). Biological indicators are standardized products inoculated with spores of resistant strains of bacteria that are placed within a load of waste as it is processed. For more information, please refer to Perkins (9). o Treatment Combinations. In many instances, the most cost- effective means of treating the infectious waste spectrum of an institution might be a combination of treatment methods, both on- and off-site. For example, laboratory wastes can be steam sterilized since most laboratories already have autoclaves, and sharps, animal bedding, and pathological waste can be incinerated. o Disposal. Generally, infectious waste that has been treated by an approved method can be disposed of as common solid waste in a sanitary landfill. Again, it is prudent for each hospital or institution to contact its local and state governments to insure compliance with any restrictions. 4. Contineen CY Plannim Any effective waste management program should include a contingency plan to provide for emergency situations.. An office or responsible person should be designated as a resource to call when the following situations arise:

22 54 Spills. The plan should include written procedures for cleanup, personnel protection, and disposal of the spill residue. The procedures should be available at sites of infectious waste generation, storage, and disposal. Rupture of plastic bags. When solid infectious waste is inadvertently dispersed, the contingency plan should indicate the person responsible for repackaging the waste. Equipment failure. If a treatment method is disrupted because of equipment failure, plans need to be made for storage and/or alternative treatment methods. For example, is off-site treatment readily available, or is there a back-up treatment method on-site? 5. Staff Training. Once developed, the infectious waste management plan should be explained not only to those employees who transport the waste, but also to those employees who generate the waste. They should know what kind of work practices are necessary, what protective garments need to be used for handling infectious materials, etc. The staff should be aware of exposure policies offered by the Employee Health Office. For example, what can be done for an employee when exposed to a contaminated needle? How and when should it be reported? Staff training should begin during employee orientation, and should recur in continuing education classes and when management practices are changed.

23 55 6. Policv Implementation. The EPA recommends that a designated person or division be responsible for making policy decisions and for implementing the program. This information should be written into the program with strong support from administration. Conclusions There is no one optimum infectious waste management plan that is effective for all hospitals or institutions. Each facility will need to consider budgetary constraints, availability of cost-effective treatment.methods, and local, state, and federal regulatory constraints in order to design its own unique plan. The EPA as well as the state of North Carolina offer reasonable guidelines, but contain trgrayt' areas that are subject to interpretation. It is important that a responsible person or division within the facility make rational decisions that comply with regulations, and that the infectious waste management plan be made available to all employees. The infectious waste manager is in a unique position as a liaison with the public regarding a realistic approach to infectious waste management. Diseases such as AIDS will continue to feed emotional rather than rational decisions regarding infectious waste within local and state governments. National legislation is not forthcoming because "considerable evidence that these wastes cause harm to human health and the environment is needed to support Federal rulemaking" (3).. Therefore, it is necessary that an infectious waste management plan first address the occopational risk within the facility, and then insure proper treatment and safe packaging for transport and disposal to protect the off-site handlers from the small, if not negligible, risk posed by infectious waste.

24 56 References 1. Local laws of New York City, no. 57, Aug. 2, In Hemorrhage from the hospitals: Mismanagement of Infectious Waste in New York State. Legislative Commission on Solid Waste Management, Albany, N.Y.. March 25, NCAC 10G; Statutory Authority G.S. 130A-294; Eff. April 1, 1982; amended Eff. July 1, U.S. Environmental Protection Agency, Office of Solid Waste. EPA Guide for Infectious Waste Management, May, Washington, D.C. 4. Garner, J.S. and B.P. Simmons CDC Guidelines for Isolation Precautions in Hospitals. Infection Control 4: Joint Commission on Accreditation of Hospitals. In Accreditation. Manual for Hospitals, 1985 edition. Chicago, pp Rutula, W.A. and F.A. Sarubbi, Management of Infectious Waste from Hospitals. Association for Practitioners in Infection Control Annual Meeting, Atlanta, Ga. 7. Wallace, L.P., R. Zaltzman, and J.C. Burchinal Where solid waste comes from; where it should go. Mod Hosp 118(2): U.S. Pharmacopeia1 Conventin, Inc., Sterilization. In the United States Pharmacopeia. 20th revision. Rockville, MD Perkins, J.J. Principles and Methods of Sterilization in Health Sciences. 2nd edition. Charles C. Thomas, Springfield.