Members: Login Here

Don't yet have a Practice Greenhealth account? Request one HERE!

Forgot your password?

Typical Categories of Medical Waste

Pathological & Anatomical Waste

All human anatomical wastes and all wastes that are human tissues, organs, or body parts removed by trauma, during surgery, autopsy, birth, research studies, or another hospital procedure, and which are intended for disposal. Pathological waste differs from anatomical waste in that these are typically samples of tissues that are examined in a laboratory setting to understand the nature of the disease or make a diagnosis. For the most part, pathological waste refers to very small tissues sections and body material derived from biopsies or surgical procedures that are then examined in the lab. Anatomical wastes are typically distinguished as recognizable human organs, tissue and body parts, and may require special treatment under some state regulations. Some states do not consider hair, teeth and nails to be pathological/anatomical waste.

Some states require either incineration or interment for pathological waste, apparently with no provision for exceptions. Other states allow alternative treatment methods, but spell out in detail which methods are allowed. For those state that do allow alternatives to incineration for this waste stream, steam sterilization (autoclaving) is the most common method indicated. A few states (e.g. Texas) also specifically provide for a broader range of thermal and chemical treatments for pathological waste.

Check the state definition for RMW to see if this waste category is defined more specifically in a particular state.

Bulk human blood, blood products, bulk body fluids or other potentially infectious material (OPIM)

This waste category typically includes bulk waste human blood, human blood components or products derived from blood including serum, plasma and other blood components, or bulk human body fluids as defined as other potentially infectious materials (OPIM) by OSHA,  including the following human body fluids: semen, vaginal secretions, cerebrospinal fluid, synovial fluid, pleural fluid, pericardial fluid, peritoneal fluid, amniotic fluid, saliva in dental procedures, any body fluid that is visually contaminated with blood, and all body fluids in situations where it is difficult or impossible to differentiate between body fluids.

This category includes sample of these fluids taken in hematology labs, as well as drainage from surgery, and urine or feces when visibly contaminated by blood. Please note that different states have different requirements for urine, feces, menstrual blood and items contaminated with such fluids, including urinary catheter and urostomy bags, adult diapers, sanitary napkins, etc. While these fluids are not considered infectious under OSHA unless meeting the standard above, it is important to check state regulations. Some healthcare organizations have also gone a step further to get written guidance from the state department of health on proper disposal practices where the regulation leaves disposal up to interpretation.

Microbiological Waste

Microbiological waste is made up of cultures and stocks of infectious agents, and associated microorganisms and biologicals. This waste stream is primarily generated by the healthcare organization’s labs. Discarded cultures, culture dishes and devices used to transfer, inoculate and mix cultures, stocks, specimens, live and attenuated vaccines and associated items are considered microbiological waste, IF they contain organisms likely to have been contaminated by organisms likely to be pathogenic to healthy humans. Also typically included in this category are discarded etiologic agents and wastes from the production of biologicals and antibiotics likely to have been contaminated by organisms likely to be pathogenic to healthy humans, as well as waste that originates from clinical or research laboratory procedures involving communicable infectious agents.

Most of the states that make special provisions for pathological waste also have special requirements for microbiological waste.  Many hospitals autoclave their microbiological wastes prior to transport to the waste storage area, even if treating on site.  As with any treatment practices, check with your state for regional mandates and guidance.

Note: Microbiological waste that is also considered a ‘sharp’ as defined below, should be managed first and foremost as a ‘sharp’. It is also important to note what materials your laboratories are working with, as there are special guidelines from CDC on how to handle infectious microorganisms at biosafety level (BSL) 3 and BSL 4. Recent federal regulations require healthcare facility laboratories to maintain the capability of destroying discarded cultures and stocks on-site if these laboratories isolate from a clinical specimen any microorganism or toxin identified as a ‘select agent’ from a clinical specimen (Table 27 from the CDC Guidelines on Environmental Infection Control, 2003)


“Sharps” is a term applied to objects such as needles and scalpel blades – anything that can cut or puncture the skin. Their special hazard lies in the fact that, having been designed to pierce the skin, they are very efficient delivery mechanisms for putting infectious agents directly into the bloodstream. Wastes containing both infectious material and sharp objects create particular hazards for anyone handling them, or coming into contact with them. Sharps include any items that can induce “subdermal inoculation of infectious agents” or that can easily penetrate the skin, puncture waste bags and cardboard boxes, and sharp items that have been used or are intended to be used in human or animal patient care or in medical, research, or industrial laboratories, including hypodermic needles, syringes, Pasteur pipettes, capillary tubes, broken glass from the laboratory including slides and slide covers, razor blades, and scalpel blades.

There are basically two ways to address the risk of infection from sharps—mitigate the infective potential, or mitigate the sharpness. The first approach typically involves specifying treatment methods for sharps, often of the same level of stringency as those applied to pathological wastes. The second approach can involve isolating the sharps, generally in special containers, mechanically processing them, or encapsulating them. Many states spell out detailed regulations for sharps containers, including conditions to ensure that they are resistant to punctures, and that they are clearly labeled. Some states require that sharps be mechanically rendered non-sharp (using terms like “blunted” or “shredded”). Others require that they be rendered unrecognizable. There is also confusion that often needleless injection devices, heel lancers and retractable or needle destruction technologies are considered sharps under state regulation as well.

Sharps are singled out for special regulatory provisions by more states than any of the other medical waste categories. Review state regulations appropriately. Sharps also require special handling and packaging under both OSHA and DOT.

Isolation Wastes (Wastes from Highly Communicable Diseases)

This waste category includes biological waste and discarded materials contaminated with blood, excretion, exudates or secretion from humans or animals who are isolated to protect others from highly communicable diseases (Lassa fever virus, Marburg virus, monkey pox virus, Ebola virus and others (See Table 27 from the CDC Guidelines on Environmental Infection Control, 2003).

Animal Waste

Many facilities have affiliated animal research laboratories as part of their organizational footprint. This waste category includes animal carcasses, body parts, bedding and related wastes that may have been exposed to infectious agents during research, production of biologicals, or testing of pharmaceuticals.



Join in the Discussion

Participate in our forum disussion about:



Join Practice Greenhealth

Practice Greenhealth is the nation’s leading membership and networking organization for institutions in the healthcare community that have made a commitment to sustainable, eco-friendly practices.

Join Practice Greenhealth
Sitemap (click to minimize or expand)