Medical Waste

Medical wastes are generated as a result of patient diagnosis and/or treatment or the immunization of human beings or animals. The subset of medical waste that potentially could transmit an infectious disease is termed infectious waste. The Centers for Disease Control (CDC), the U.S. Environmental Protection Agency (EPA), and the World Health Organization (WHO) concur that the following wastes should be classified as infectious waste: sharps (needles, scalpels, etc.), laboratory cultures and stocks, blood and blood products, pathological wastes, and wastes generated from patients in isolation because they are known to have an infectious disease. Medical wastes can also include chemicals and other hazardous materials used in patient diagnosis and treatment. In some cases this subset of medical waste is classified as hazardous waste. Hospitals, clinics, research facilities, diagnostic labs, and other facilities produce medical waste. The bulk of the wastes generated by most health care facilities, however, is municipal solid waste (MSW), or trash. MSW includes large quantities of paper, cardboard and plastics, metals, glass, food waste, and wood. Medical waste, though a smaller portion of the total health care waste stream, is of special concern because of the potential hazards from pathogens that may be present, or from hazardous chemicals.

Risk and Health Care Waste

In the late 1980s there were a series of syringe wash ups on beaches along the East Coast of the United States, which were mistakenly attributed to health care facilities. The federal Medical Waste Tracking Act (MWTA) was passed and the EPA attempted to set standards for managing the infectious waste component of medical waste that they renamed regulated medical waste. Few states adopted its stringent guidelines. The MWTA expired in the early 1990s, making each state responsible for establishing its own classification and management guidelines for medical waste.

There are very few documented cases of disease transmission from contact with medical waste. The notable exception is needle stick, or "sharps" injuries. Paralleling the concern over beach wash ups of medical waste, was a growing awareness of the increase in HIV-AIDS and other cases of infectious diseases being diagnosed and treated in health care settings. This, along with a series of events, led to the Occupational Safety and Health Administration (OSHA), which established rules designed to protect health care workers (OSHA blood-borne pathogen standards and universal precautions) by stipulating the need for such personnel to wear protective clothing and equipment, and to take special precautions when handling or disposing of sharps. The interpretation of rules surrounding worker safety regulations led to some confusion over waste classification, thus causing a greater amount of wastes to be considered as potentially infectious. (For example, under the OSHA universal precautions guidelines, a worker handling a bandage with a single drop of blood on it should wear gloves, but the waste itself would most likely not be classified as infectious.)

Noting that there are multiple risks inherent in medical waste including toxic chemicals and radioactive materials, the WHO has chosen to use the term health care risk waste instead of medical waste.

Regulation

Many regulations govern the labeling, handling, treatment, transport, storage, and disposal of medical waste, including: Department of Transportation (DOT) rules for the packaging and transportation of wastes; OSHA guidelines for worker safety, waste labeling and handling; the Resource Conservation and Recovery Act (RCRA), which governs the management of hazardous materials and wastes, including hazardous pharmaceutical wastes; Nuclear Regulatory Commission (NRC) radioactive waste management practices, Drug Enforcement Agency (DEA) regulations for handling and disposing of controlled substances such as narcotics; the Clean Air Act, which regulates emissions from incinerators; the Clean Water Act, which defines what may be disposed of down the drain; state environmental and health rules that define certain types of waste and determine the specifics of waste treatment, as well as requirements for storage, labeling, handling, and segregation. Most other countries have similar multitiered regulatory regimes, such as Australia, where a national standard defines clinical waste (what is termed medical waste in the United States). However, the particulars of regulation are left to the discretion of individual Australian states.

Proper Management, Treatment, and Disposal

There is general consensus among professional health care organizations, the waste management industry, and regulators that proper management starts with the identification of wastes requiring special handling and treatment because of their hazardous nature (biological, chemical, or radioactive). Waste identification is necessary for proper segregation, so that only those wastes needing special treatment and handling are treated. Proper management of all waste streams enhances worker safety, protects the environment, and can reduce costs.

Wastes that are deemed potentially infectious may be treated prior to disposal by a number of different technologies that either disinfect or sterilize them. These technologies include incineration, steam sterilization, dry heat thermal treatment, chemical disinfection, irradiation, and enzymatic (biological) processes among others. In 2002 there were more than one hundred specific technologies in use. In order for treatment systems to work properly, distinctive protocols for the classification and segregation of wastes must be in place. Most treatment technologies for infectious wastes cannot process chemical or radioactive waste. Misclassification and inappropriate treatment of infectious wastes can result in significant harm to the environment and human health; for example, residual chemotherapeutic agents are should not be treated in autoclaves, but rather should be set aside and treated by either incineration (hazardous waste incinerators) or chemically neutralized where feasible.

The EPA has cited medical waste incinerators as among the top sources of mercury and dioxin pollution. New regulations governing the operation of, and emissions from, medical waste incinerators in the late 1990s have resulted in the closure of most such incinerators in the United States. Other countries such as the Philippines have completely banned incineration because of its adverse environmental impacts.

The health care industry is rapidly changing in ways that continue to have significant impact on the volume and characteristics of wastes produced.

• New (e.g., laproscopic and laser) surgical techniques result in procedures that produce very little blood-contaminated waste.
• Advances in cancer treatment have produced many drugs used in chemotherapy that are highly toxic in small quantities, producing more hazardous chemical wastes.
• Patient residence time in hospitals has declined. Procedures that previously required an extended stay now commonly occur on an outpatient basis without necessitating an overnight stay.
• Home care continues to grow, shifting the location of service delivery. Dialysis, chemotherapy, and hospice care are but a few examples of health care that often take place in a home setting, the result being that many wastes regulated as infectious or hazardous waste in a hospital are being disposed of as ordinary trash at curbside. (Household waste is exempt from many regulations.)
• As hospitals close their incinerators, biohazardous and sometimes (inadvertently) hazardous wastes are being hauled significant distances to centralized facilities for treatment and disposal.
• All of these changes represent new challenges in continuing efforts to properly define, classify, regulate and manage medical wastes.

see also Dioxin; Endocrine Disruption; Hazardous Waste; Incineration; Infectious Waste; Mercury; Occupational Safety and Health Administration (OSHA); Resource Conservation and Recovery Act.

Bibliography

bisson, connie leach; mcrae, glenn; and gusky shaner, hollie. (1993). an ounce of prevention: waste reduction strategies for health care facilities. chicago: american hospital association.

health care without harm. (2001). "non-incineration medical waste treatment technologies." washington, d.c.

mcrae, glenn, and gusky shaner, hollie. (1996). guidebook for hospital waste reduction planning and program implementation. chicago: american hospital association.

pruss, a.; giroult, e.; and rushbrook, p. (1999). safe management of wastes from health-care activities. geneva: world health organization.

rutala, william a., and mayhall, c. glen. (1992). "medical waste: the society for hospital epidemiology of america position paper." infection control and hospital epidemiology 13:38–48.

internet resources

centers for disease control web site. available from http://www.cdc.org.

u.s. environmental protection agency web site. available from http://www.epa.gov.

Hollie Shaner and Glenn McRae

PHARMACEUTICAL WASTE

Pharmaceutical wastes are diverse and in some cases trace amounts can be discarded as medical waste. Certain pharmaceuticals are hazardous wastes when disposed, and some common ones are "acute" hazardous wastes under RCRA regulations (e.g., Epinephrine, Nitroglycerin, Warfarin (>0.3%)).

Medical Waste

Introduction

Medical waste, also termed health-care waste, is garbage and effluent (liquid waste) produced by hospitals, clinics, research facilities, laboratories, and veterinary facilities. Most health-care waste (up to 85%) is similar to ordinary non-hazardous household trash, but about 10% consists of potentially infectious biological materials and 5% of hazardous wastes (chemical, radioactive, and pharmaceutical substances). Sometimes, the term medical waste is restricted to the infectious/hazardous component of health-care waste. In the United States, medical waste is governed by the Medical Waste Tracking Act of 1988, which required the U.S. Environmental Protection Agency (EPA) to establish a medical-waste tracking program.

Historical Background and Scientific Foundations

Medical waste first became a major political issue in the United States in 1987 and 1988, when large amounts of medical waste and other trash washed up on New Jersey beaches. The waste included disposable syringes (injection needles), so the event came to be known as the Syringe Tide. Hearing about the repulsive and possibly dangerous pollution, thousands of tourists stayed away from the Jersey shore, usually a prime tourist destination, costing the state almost one billion dollars in lost business revenue. New Jersey blamed New York City for the waste, and indeed, it was eventually traced to New York’s Fresh Kills Landfill on Staten Island. In late 1987, a federal judge approved an agreement in which New York City accepted partial responsibility for the medical and other trash washing up on New Jersey beaches, and agreed to pay one New Jersey town, Woodbridge, $1 million in compensation and to pay for cleanup of the town’s shoreline. The suit actually long predated the Syringe Tide, being brought by the town in 1979. Regular collection of floating trash by New York City and the U.S. Army Corps of Engineers has kept closings of beaches due to washed-up trash much lower since 1989.

Publicity over the medical waste washing up on New Jersey beaches led to hundreds of pieces of legislation (according to the EPA) originating from town and city governments up to Congress. The most far-reaching law pertaining to medical waste to come from the Syringe Tide incident was the Medical Waste Tracking Act of 1988. This laid out a federal definition of what constitutes medical waste and mandated a cradle-to-grave tracking system for June 1989 to June 1991 under which hospitals would have to keep track of their medical waste so that its proper disposal, usually by incineration, would be verifiable. Penalties for mismanagement of medical waste were established. The tracking system was applied only in New York, New Jersey, Connecticut, Rhode Island, and Puerto Rico and expired in 1999.

What Is Medical Waste?

The hazardous fraction of medical waste can be broken down into a number of sub-categories. Different expert sources use somewhat different categories, but the World Health Organization of the United Nations recognizes the following:

• Infectious waste: includes used bandages and dressings; swabs, sponges, tubes, and other disposable products used in surgery; infectious cultures from laboratories; all wastes from infectious-disease wards.
• Pathological waste: tissue samples, body parts removed during surgery or autopsy, blood and blood products, dead infected laboratory animals, body fluids, etc.
• Sharps: all items that can cut or puncture the skin: most commonly needles, used surgical tools, and broken glass.
• Pharmaceutical waste: unused drugs of all kinds.
• Genotoxic waste: waste containing substances that interfere with the functioning of DNA, whether by causing cancer, interfering with fetal development, or causing mutations. The main substances in this category are cytotoxic (cell-toxic) drugs, widely used in chemotherapy for cancer to interfere with the replication of cancer cells.
• Chemical waste: waste containing chemical substances such as disinfectants, solvents, cleansers, preservatives (e.g., formaldehyde), photographic chemicals, oils, pesticides, acids, or the like.
• Heavy metals: wastes containing a high heavy-metal content. The most common toxic heavy metals are lead and mercury, which are found in batteries, old thermometers, and wall-mounted sphygmomanometers (blood-pressure gauges), and other wastes.
• Pressurized containers: all containers containing gas under pressure, such as handheld aerosol cans and oxygen tanks.
• Radioactive waste: all radioactive materials, including sealed sources of radiation from radiotherapy machines and substances used in nuclear medicine.

WORDS TO KNOW

RADIOACTIVITY: The property possessed by some elements of spontaneously emitting energy in the form of particles or waves by disintegration of their atomic nuclei.

SHARPS WOUNDS: Wounds caused by discarded medical instruments including hypodermic needles and, scalpels (knives) and other sharp objects potentially contaminated by human contact.

TOXIC: Something that is poisonous and that can cause illness or death.

Impacts and Issues

The type of hazard posed by medical waste depends on what type, or mixture of types, of waste it contains. It may contain infectious agents (viruses or bacteria that can cause disease), genotoxic agents, toxic chemicals, radioactivity, or sharps that can cause wounds and transmit infections (e.g., of HIV, the virus that causes AIDS). Persons working in health-care facilities are most exposed to these hazards; the next most exposed category includes people who handle waste directly from such facilities, such as garbage collectors.

Injury by sharps is the most common form of harmful encounter with medical waste. For example, from 46,000 to 70,000 nurses are injured by used sharps every year in the United States; from 500 to 7,300 waste handlers are injured. Cases of disease transmission by hospital waste have been documented: most of these involve hospital workers handling sharps. For example, by June 1996, the U.S. Centers for Disease Control and Prevention (CDC) had identified 51 cases of HIV infection due to occupational exposure. Most of the cases were from sharps wounds; four involved contact with infected blood. Data from Japan show that puncture by a used hypodermic needle in medical waste conveys a 0.3% chance of contracting HIV, a 3% chance of contracting viral hepatitis B, and a 3 to 5% chance of contracting viral hepatitis C.

The EPA, after the two years when it tracked medical waste in part of the United States, concluded that the potential of medical waste to cause disease is greatest when it is newly generated. At that point it contains the most living disease organisms and its chemicals are most concentrated. Risk from exposure to medical waste decreases as the waste ages.

Few data are available on the risks to health workers and the public of chemical, genotoxic, radioactive, and other sub-categories of medical waste. However, these are among the most potentially harmful types of medical waste, likely to cause much more disease over time than infectious agents. Of particular concern are heavy metals. According to the EPA, over 90% of potentially infectious medical waste is disposed of by incineration. Incineration is not appropriate for heavy metals, since they are dispersed more widely by burning and not destroyed. Medical waste incinerators (most of which are located at hospitals) were once a major source of mercury pollution: In 1990, they were responsible for 25% of U.S. mercury emissions. The EPA states that its regulations governing emissions from medical-waste incinerators, promulgated in 1997, have reduced mercury emissions from medical-waste incineration by 94%.

One well-documented case illustrates the importance of containing radioactive medical wastes. In the Brazilian town of Goiano, a radiotherapy institute was closed in 1985. (Radiotherapy is the selective use of radiation to kill cancer cells.) A machine containing a large quantity of the radioactive nuclide 137Cesium, whose radiation was once used to treat cancer, was abandoned in the facility. Local people, scavenging gear from the site, obtained the lead-encased source and broke it open, revealing its blue contents. Having no idea what it was, they gave the sticky radioactive powder to children to play with, who painted their skin with it, and otherwise

spread it widely. Four people died from radiation exposure and hundreds more were exposed, causing long-term health consequences that have not been tracked by the Brazilian government.

Medical waste is also generated by home use of pharmaceuticals, home dialysis, and other products. In early 2008, a five-month investigation by the Associated Press revealed that a wide variety of prescription drug metabolites (drugs requiring a doctor’s order) are found in most U.S. drinking water: these drugs include mood stabilizers, anti-epileptics, sex hormones, and antibiotics. The likely source of these drugs was not only health-care facilities, but also home consumers of the drugs, who pass the unmetabolized drug out of their bodies in urine and dump unused drugs into the toilet. Flushed drugs enter the municipal wastewater streams and spread out into the environment. Whether any of the drugs exist in amounts large enough to be harmful is debated by epidemiologists (scientists who study the causes of disease in populations). Since February, 2007, the U.S. government has advised persons who are disposing of unused drugs not to flush them down the toilet, but mix them with some repellent material such as coffee grounds (to insure that they will not be retrieved from the garbage and eaten by children) and to put them out with the regular trash for eventual landfill burial.

Primary Source Connection

In response to the pollution of beaches by medical waste, Congress enacted the Medical Waste Tracking Act of 1988 (MWTA), an excerpt of which follows, as an amendment to the Solid Waste Disposal Act. The MWTA established a two-year program that studied the disposal of medical wastes in several states on the East Coast as well as states adjacent to the Great Lakes. The program had four major goals. The first was to develop clear definitions of medical waste. The second was to develop a tracking system for medical waste from the point of origin through the final disposal point. The program also developed standardized measures for packing, labeling, and storing medical waste. Finally it established penalties for not adhering to the medical waste tracking system.

The formal outcome of the Medical Waste Tracking Act of 1988 was a set of recommendations called Standards for the Tracking and Management of Medical Waste. Although the Standards were only in place for two years, the MWTA resulted in stricter laws and regulations for the disposal of medical wastes in state and local governments. A multi-billion dollar industry developed in response to these requirements. Facilities that are properly equipped to autoclave, incinerate, microwave, chemically disinfect, or thermally inactivate medical wastes have become an important part of the medical waste disposal stream. Businesses that contract with hospitals, doctors and dentists offices, veterinarians, and research laboratories are required to obtain permits and to adhere to strict performance standards.

MEDICAL WASTE TRACKING ACT OF 1988

TITLE 42, CHAPTER 82, SUBCHAPTER X

Sec. 6992. Scope of demonstration program for medical waste

(a) Covered States

The States within the demonstration program established under this subchapter for tracking medical wastes shall be New York, New Jersey, Connecticut, the States contiguous to the Great Lakes and any State included in the program through the petition procedure described in subsection (c) of this section, except for any of such States in which the Governor notifies the Administrator under subsection (b) of this section that such State shall not be covered by the program.

(b) Opt out

1. If the Governor of any State covered under subsection (a) of this section which is not contiguous to the Atlantic Ocean notifies the Administrator that such State elects not to participate in the demonstration program, the Administrator shall remove such State from the program.
2. If the Governor of any other State covered under subsection (a) of this section notifies the Administrator that such State has implemented a medical waste tracking program that is no less stringent than the demonstration program under this subchapter and that such State elects not to participate in the demonstration program, the Administrator shall, if the Administrator determines that such State program is no less stringent than the demonstration program under this subchapter, remove such State from the demonstration program.
3. Notifications under paragraphs (1) or (2) shall be submitted to the Administrator no later than 30 days after the promulgation of regulations implementing the demonstration program under this subchapter.

(c) Petition in

The Governor of any State may petition the Administrator to be included in the demonstration program and the Administrator may, in his discretion, include any such State. Such petition may not be made later than 30 days after promulgation of regulations establishing the demonstration program under this subchapter, and the Administrator shall determine whether to include the State within 30 days after receipt of the State’s petition.

(d) Expiration of demonstration program

The demonstration program shall expire on the date 24 months after the effective date of the regulations under this subchapter.

Sec. 6992a. Listing of medical wastes

(a) List

Not later than 6 months after November 1, 1988, the Administrator shall promulgate regulations listing the types of medical waste to be tracked under the demonstration program. Except as provided in subsection (b) of this section, such list shall include, but need not be limited to, each of the following types of solid waste:

1. Cultures and stocks of infectious agents and associated biologicals, including cultures from medical and pathological laboratories, cultures and stocks of infectious agents from research and industrial laboratories, wastes from the production of biologicals, discarded live and attenuated vaccines, and culture dishes and devices used to transfer, inoculate, and mix cultures.
2. Pathological wastes, including tissues, organs, and body parts that are removed during surgery or autopsy.
3. Waste human blood and products of blood, including serum, plasma, and other blood components.
4. Sharps that have been used in patient care or in medical, research, or industrial laboratories, including hypodermic needles, syringes, pasteur pipettes, broken glass, and scalpel blades.
5. Contaminated animal carcasses, body parts, and bedding of animals that were exposed to infectious agents during research, production of biologicals, or testing of pharmaceuticals.
6. Wastes from surgery or autopsy that were in contact with infectious agents, including soiled dressings, sponges, drapes, lavage tubes, drainage sets, underpads, and surgical gloves.
7. Laboratory wastes from medical, pathological, pharmaceutical, or other research, commercial, or industrial laboratories that were in contact with infectious agents, including slides and cover slips, disposable gloves, laboratory coats, and aprons.
8. Dialysis wastes that were in contact with the blood of patients undergoing hemodialysis, including contaminated disposable equipment and supplies such as tubing, filters, disposable sheets, towels, gloves, aprons, and laboratory coats.
9. Discarded medical equipment and parts that were in contact with infectious agents.
10. Biological waste and discarded materials contaminated with blood, excretion, excudates [1] or secretion from human beings or animals who are isolated to protect others from communicable diseases.
11. Such other waste material that results from the administration of medical care to a patient by a health care provider and is found by the Administrator to pose a threat to human health or the environment.

(b) Exclusions from list

The Administrator may exclude from the list under this section any categories or items described in paragraphs (6) through (10) of subsection (a) of this section which he determines do not pose a substantial present or potential hazard to human health or the environment when improperly treated, stored, transported, disposed of, or otherwise managed

Sec. 6992b. Tracking of medical waste

(a) Demonstration program

Not later than 6 months after November 1, 1988, the Administrator shall promulgate regulations establishing a program for the tracking of the medical waste listed in section 6992a of this title which is generated in a State subject to the demonstration program. The program shall:

1. provide for tracking of the transportation of the waste from the generator to the disposal facility, except that waste that is incinerated need not be tracked after incineration,
2. include a system for providing the generator of the waste with assurance that the waste is received by the disposal facility,
3. use a uniform form for tracking in each of the demonstration States, and

1. include the following requirements:
2. A requirement for segregation of the waste at the point of generation where practicable.
3. A requirement for placement of the waste in containers that will protect waste handlers and the public from exposure.
4. A requirement for appropriate labeling of containers of the waste.

(b) Small quantities

In the program under subsection (a) of this section, the Administrator may establish an exemption for generators of small quantities of medical waste listed under section 6992a of this title, except that the Administrator may not exempt from the program any person who, or facility that, generates 50 pounds or more of such waste in any calendar month.

(c) On-site incinerators

Concurrently with the promulgation of regulations under subsection (a) of this section, the Administrator shall promulgate a recordkeeping and reporting requirement for any generator in a demonstration State of medical waste listed in section 6992a of this title that:

1. (1) incinerates medical waste listed in section 6992a of this title on site and
2. (2) does not track such waste under the regulations promulgated under subsection (a) of this section. Such requirement shall require the generator to report to the Administrator on the volume and types of medical waste listed in section 6992a of this title that the generator incinerated on site during the 6 months following the effective date of the requirements of this subsection.

(d) Type of medical waste and types of generators

For each of the requirements of this section, the regulations may vary for different types of medical waste and for different types of medical waste generators

U.S. Congress

U.S. CODE. “MEDICAL WASTE TRACKING ACT OF 1988. AN AMENDMENT TO THE SOLID WASTE DISPOSAL ACT.”TITLE 42, CHAPTER 82, SUBCHAPTER X, SECTIONS 6992, 6992A AND 6992B.

See Also Toxic Waste

BIBLIOGRAPHY

Books

Dutta, Subijoy. Environmental Treatment Technologies for Hazardous and Medical Wastes: Remedial Scopand Efficacy. New York: McGraw-Hill, 2007.

Periodicals

Narvaez, Alfonso. “New York City to Pay Jersey Town $1 Million Over Shore Pollution.” New York Times (December 8, 1987).

Web Sites

CNN.com“Prescription Drugs Found in Drinking Water Across U.S.” March 10, 2008. http://www.cnn.com/2008/HEALTH/03/10/pharma.waterl.ap/ (accessed May 10, 2008).

U.S. Environmental Protection Agency. “Medical Waste.” http://www.epa.gov/epaoswer/other/medical/ (accessed May 10, 2008)

U.S. Environmental Protection Agency. “Medical Waste Tracking Act (1988).” http://www.epa.gov/epaoswer/other/medical/mwpdfs/mwta.pdf (accessed May 10, 2008).

World Health Organization. “Medical Waste.” http://www.who.int/topics/medical_waste/en/ (accessed May 10, 2008).

World Health Organization. “Safe Management of Wastes from Health-Care Activities.” http://www.healthcarewaste.org/en/documents.html?id=1 (accessed May 10, 2008).

Larry Gilman

Medical waste

Medical waste is a subcategory of hazardous waste that is attracting increasing concern. The Environmental Protection Agency (EPA) lists the following categories of medical waste: cultures and stocks; pathological wastes which includes body parts; blood and blood products; used "sharps" such as needles and scalpels; animal waste or animal corpses which have been inoculated with infectious substances in medical research; isolation wastes, which come from people with highly contagious diseases; and unused, discarded "sharps."

Ten to fifteen percent of medical waste is considered infectious, although guidelines on just what is infectious medical waste vary from state to state. As a result, state and federal guidelines on disposal of these wastes are a hodgepodge of confusing laws and regulations. And the guidelines that do exist usually exempt generators of 50 pounds (23 kg) or less per month from any regulatory action.

The need to address medical waste began soon after such items as syringes, IV bags, and scalpels were observed washing up on ocean beaches in the summer of 1988. Congress directed the EPA to gather data on their sources, associated health hazards, and current procedures and regulations for management and disposal and to evaluate the health hazards associated with transporting them, incinerating them, burying them in a landfill , and disposing of them in a sanitary sewer system.

A two-year, voluntary program enacted by Congress, the Medical Waste Tracking Act of 1988, was instituted in response to public concern over the treatment of medical waste. The Act created a "cradle-to-grave" tracking system based on detailed shipping records, similar to the program in place for hazardous waste. The pilot program has now expired, the EPA data has been sent to Washington administrators, and any action on the findings of the EPA's study is in limbo. It is doubtful that the EPA report on medical waste will ever be submitted to Congress or find its way into the Federal Register because many of the states that participated in the program went on to pass strict medical-waste management guidelines of their own. All the states participating at least revised their municipal solid waste guidelines to include the category of medical waste, whether or not management practices were included.

Another complicating factor in the regulation of medical waste is that at least four different federal agencies are involved with medical-waste issues: the EPA, the Occupational Safety and Health Administration (OSHA), the Centers for Disease Control (CDC), and the Agency for Toxic Substances and Disease Registry .

The EPA's study reported that 3.2 million tons of medical waste was produced in the United States each year. Not surprisingly, hospitals, long-term health care facilities, and physician's offices are the major producers of medical wastes, which account for about 0.3% by weight of all municipal solid waste . The EPA found out that current practices of management and disposal range from handling the waste as nonhazardous municipal solid waste to strict segregation, packaging, labeling, and tracking from the generator to the disposal site, the so-called "cradle-to-grave" management.

Health care workers are required by federal law to segregate medical waste in special containers; if the waste is transported for treatment, it must be labeled with the generator's name and carry a biological hazard symbol. But facilities that produce less than 50 lb (23 kg) of medical waste per month are exempt from most requirements. Home and small generator medical wastes fall through the cracks. Insulin-dependent diabetics, for instance, typically dispose of used syringes in their household trash or flush them down the toilet. In some northeastern cities, New York City for example, antiquated sewage systems pour material into rivers and oceans during heavy rainfalls. Depending on tides and currents, syringes can end up on beaches, which is what New York and New Jersey coastlines experienced in 1988 and 1989.

A growing source of medical waste that is not regulated is that generated by home health-care providers. As a result of new patient-care strategies and rising medical costs, more long-term illnesses are being treated at home. That means that medical waste is being disposed of in ordinary household trash. Medical clinics and intravenous drug users are also suspected of contributing to unsafe dumping of medical wastes. Even U.S. Navy vessels contributed to beach medical waste.

The need to address the problem evolved long before wastes washed up on northeastern beaches, however. Over the last 10 years, and partly in response to the AIDS and hepatitis epidemics, the use of disposable health care products has contributed to the increased volume of medical waste. Cost-containment measures have increased the use of plastic disposables in health care settings. From syringes to bedpans, health care aids are increasingly thrown away.

Common treatment techniques of medical waste include steam sterilization and incineration , although some waste is discarded into sewage systems. During autoclaving, the waste is exposed to steam at a temperature of 250°F (121°C) for at least 45 minutes. Autoclaving fails to reduce the volume of waste that must be landfilled, and is only preferred in areas where there is no appropriate incineration equipment. Proper incineration efficiently destroys all categories of infectious wastes, effectively kills live and dormant forms of pathogenic organisms, and alters the waste volume.

About 60 percent of medical waste is treated on site at hospital facilities. After treatment, ash residues or sterilized and disinfected materials must be transported to commercial treatment facilities or taken directly to landfills. Other options for medical waste treatment include compaction , microwaving, and mechanical or chemical disinfection, which could be less costly and alleviate concerns about emissions from incinerators.

According to the congressional Office of Technology Assessment (OTA), air emissions of dioxin and heavy metals from hospital incinerators average 10 to 100 times more per gram of waste burned than emissions from well-controlled municipal waste incinerators. And while waste generators are generally required to track with manifests the route their wastes take to reach disposal, strict requirements do not exist for on-site treatment facilities.

Some industry watchers, environmentalists, and policy makers are advocating a medical waste disposal program similar to some in Europe. Virtually all medical wastes in Switzerland and Germany, for example, go to regional incineration facilities. Stringent air-quality regulations in these countries make it impractical for hospitals to do on-site incineration, but the regional facilities made advanced air pollution control devices cost-effective. In Munich, operators dump the resulting ash in specially lined landfills. Hospitals in Canada are turning away from disposable supplies in favor of products that can be cleaned and reused.

For a regional system to work, however, medical waste must be safely transported. In the United States, there are no federal statutes governing the transport of medical refuse. Refrigerated trucks legally can and do carry food after transporting medical wastes.

A proposal to manage home users of syringes and medicines that end up in municipal solid waste landfills would include a pharmacy "swap" system. In Switzerland and Germany, for example, pharmacies accept old medicines for appropriate disposal, then send the medicine to regional incineration outlets. A deposit-and-return system on syringes has been advocated in this country to insure the safe disposal of syringes.

[Linda Rehkopf ]

RESOURCES

BOOKS

Moeller, D. W. Environmental Health. Cambridge: Harvard University Press, 1992.

PERIODICALS

Carlile, J. "Finding Disposal Options for Medical Waste." American City and County (November 1989): 66.

Groves, L. "Hospitals Re-Think Disposables." Alternatives (January-February 1993): 13.

Hershkowitz, A. "Without a Trace: Handling Medical Waste Safely." Technology Review (August-September 1990): 35.

"Managing Medical Waste." The Futurist (September-October 1991): 49. "Tracking Seaside Medical Wastes." Science News (September 16, 1989): 191.

MEDICAL WASTE

Medical waste is generally defined as any solid waste generated during the medical diagnosis or treatment of humans or animals, in related research, or in the production of biologicals used in clinical activities. Concern about medical waste streams has been growing. Syringes washing up on New Jersey beaches in the 1980s following massive illegal dumping of medical wastes into New York harbor threw a spotlight on the issue. Similar beach problems have occurred in Britain and have been suggested to be a cause of hepatitis B among users of recreational waters.

A number of factors make management of medical wastes more difficult than other waste streams. Standard landfill disposal is complicated by the potential for infection of workers and of the general public. On-site incineration of hospital wastes, a common practice that effectively destroys infective organisms, is of increasing concern as a source of dioxins due to the high chlorine content of many of the disposable plastics in common medical use. Local opposition has made it more difficult to site and plan hospital incinerators. Mercury from amalgam fillings discarded in dental offices has been suggested to be a cause of mercury discharge into surface water from publicly owned water-treatment works.

While there are federal guidelines concerning medical wastes, including a 1989 Medical Waste Tracking Act administered by the U.S. Environmental Protection Agency (EPA), the major regulatory control is by state and local authorities. The increased cost of safe disposal of medical waste has led to efforts to reduce the size of the waste stream, including consideration of a return to reusable syringes, endoscopy tubes, and other medical devices. This requires a careful assessment of the tradeoff with simplicity of use, certainty of sterility, and lower costs provided by the disposable items. There is also a tradeoff between increased medical-waste disposal costs and the likelihood of illegal dumping. Clinically useful plastics formulated without chlorine are also being actively sought to decrease the risk of dioxins from incineration.

Not all medical waste comes from obvious point sources such as hospitals, doctors' offices, clinical laboratories, and research facilities. Over a million syringes are used at home by diabetics and others on a daily basis. This has led to community-based approaches to collect and safely dispose of these syringes and needles. Similarly, the trend toward shorter hospital stays means postoperative patients are more frequently discharged to their homes with surgical dressings and other potentially contaminated medical paraphernalia. Chronic infectious diseases are also now more likely to be treated at home than in a hospital. Patients, families, and visiting nurses should be instructed in the proper handling of these wastes. Landfilling of medical wastes is a particular problem in many developing countries, where scavenging of landfills is an organized activity among the poor. In addition to exposure to infectious agents, there have been instances where discarded radioactivity sources, such as cobalt used in the treatment of cancer, have been recycled into the community with devastating effects.

Bernard D. Goldstein

(see also: Environmental Protection Agency; Municipal Solid Waste; Ocean Dumping; Sewage System )

Bibliography

Phillip, R.; Pond, K.; and Rees, G. (1997). "Research and the Problems of Litter and Medical Wastes on the U.K. Coastline." British Journal of Clinical Practice 51(3):164–168.

Phillips, G. (1999). "Microbial Aspects of Clinical Waste." Journal of Hospital Infection 41:1–6.

Thomas, C. S. (1977). "Management of Infectious Waste in the Home Care Setting." Journal of Intravenous Nursing 20(4):188–192.