Issues Magazine

Hospital Waste

By Forbes McGain

The increasing problem of hospital waste has spurred moves to explore barriers to and opportunities for reusing products and recycling, including life cycle assessment.

Large amounts of waste are generated by hospitals. Victoria’s public hospital sector produces the waste equivalent of 200,000 householders and spends about $10 million annually disposing of this waste (http://www.dhs.vic.gov.au/environment/waste).

Medical waste is considered “different” to other wastes, such as those from households, principally due to infectious (“clinical”) waste. Clinical waste is defined according to the Guidelines of the Australian and New Zealand Waste Industry Group as “human tissue, including materials or solutions containing or contaminated with blood”. Australia has no national data for rates of production of medical waste. My own hospital has a rate of around

5 kg/patient/day, but this varies considerably according to the “intensity” of the hospital. Approximately 15–25% is infectious, with marked variation both between and within hospitals and considerable non-infectious cross-contamination.

The concept of clinical audit as a normal part of quality assurance is now widely accepted and encouraged across medical specialties. Auditing, however, has not been widely adopted as a means to control and reduce environmental pollution caused by medical care, and there is currently no mandatory auditing of the true contents of hospital waste and opportunities for recycling in Australia.

Why is hospital waste constantly increasing? Excessive packaging of medical items is significant. More significantly, single-use/disposable items have become the default, replacing reusable alternatives. Common reasons for this trend include infection control, cost, healthcare staff preference and manufacturer preference. The decision to purchase a medical product is often based upon personal opinion or anecdotes and does not generally consider environmental impacts.

Separation of infectious waste from “other” waste streams has been the domain of infection control for many decades in most countries. Constant vigilance is required to keep waste streams separate, a factor potentially hampering efforts to recycle non-infectious waste. On the contrary, studies in the UK by Terry Tudor and colleagues (Waste Management, 2008) and many “in-house” analyses have shown that there is considerable cross-contamination of infectious waste with non-infectious items. In Australia, hospital infectious waste costs approximately $1/kg, tenfold that of non-infectious/general waste, providing a strong financial reason for separation of waste streams.

Almost 20 years ago the article “Disposable products in the hospital waste stream” by Daniel Gilden and colleagues (Western Journal of Medicine, 1992), alerted readers to the fact that the amount of disposable products in hospitals would significantly increase despite the declining availability and increased cost of landfill. Measures were suggested to substantially reduce hospital waste through substitution, minimisation and particularly recycling of disposable products. At a similar time, Myles Tieszen and James Gruenberg showed that surgical waste could be reduced by 93% simply by recovering disposable linen, paper and recyclable plastic (Journal of the American Medical Association, 1992). In the intervening years there is almost no literature suggesting that any of the authors’ recommendations have been incorporated into medical practice. One of the few papers in the medical literature suggesting a change to improved hospital environmental practice came from Marcus Dettenkofer and colleagues at the University of Freiburg, Germany, and was published in 2000 (Environmental Management).

There is a reluctance to participate in recycling of infectious and non-infectious medical waste due to the perceived risk to waste-handling personnel. In 1992, William Rutala and Glen Mayhall provided a scientific analysis of “infectious” waste (Infection Control and Hospital Epidemiology). By comparing average household waste with medical waste it was found that household waste contains more microorganisms with pathogenic potential for humans than medical waste. In addition, the only medical waste that has been associated with infectious disease transmission is contaminated sharps. Indeed, there is no scientific evidence that medical waste has ever been the source of infection for any person outside the healthcare setting.

A global market means that single-use medical devices made using overseas labour can be cheaper than reprocessing reusable devices using relatively expensive hospital sterile supply department Australian labour. Single-use versions of cotton drapes, plastic theatre gowns, medical airway and respiratory devices, compression stockings, plastic bowls and even metalware such as scissors and needle-holders are now commonplace and often the default option in Australian hospitals. In general, it is intriguing to note that the full financial and environmental costs of such change have not been rigorously examined. Greatest emphasis is applied to the financial cost of the single-use replacement, which is less expensive than the reusable item. One American company, Ascent, reprocesses expensive operating theatre equipment for reuse, although this has not been emulated in Australia. Interestingly, we found at our hospital in Melbourne that the reusable versions of plastic drug trays used for anaesthetics not only had lower energy and water use than the single-use alternatives but they also cost less, including labour costs (Anaesthesia and Intensive Care, 2010).

Often healthcare staff may prefer single-use items as they are “less hassle”. For example, daily checking of reusable anaesthetic tubing for leaks is undoubtedly more time-consuming than simply discarding single-use tubing. One can obviously see the attraction of converting from a reusable to single-use medical device for a manufacturer because more product may be sold. The term “single-use” is according to manufacturer discrepancy, not the regulatory body responsible for licensing of medical items in Australia, the Therapeutic Goods Administration.

Byeong-Kyu Lee and colleagues (Waste Management, 2002) found that plastic products form 20–30% of hospital waste, with 20–30% cardboard/paper while at least 20% of hospital waste comes from operating suites.

Recently, at least in NSW and Victoria, there have been significant increases in landfill levees, raising the price of non-recycled waste. While there are no national data for the recycling rate of medical waste in Australia, it is probably not dissimilar to the UK where currently, according to Gillett (Health Estate Journal, 2007) only 2% of waste generated by the healthcare sector is recycled. The university hospital of Freiburg in Germany has shown it is possible, through a committed workforce, to recycle at least 25% of all hospital waste.

Recycling paper, cardboard, glass and plastic can lead to both financial and environmental savings. Recycling cardboard and paper is relatively simple as they are easily recognisable and separable from other items. Oil-based plastics have become increasingly expensive yet are generally sent to landfill. Manufacturing recycled plastics uses approximately 25% of the energy compared to equivalent primary plastic products, with less (though still significant) savings for glass and cardboard. Cost-neutral-to-negative recycling programs of operating suite plastics at our hospital (Anaesthesia and Intensive Care, 2008) and glass (by Robert Gaiser and colleagues, British Journal of Anaesthesia, 2004) have been described.

Recycling medical plastics is often impeded by the variety of plastics and their lack of International Plastics Association coding. I have developed a guideline identifying commonly used medical plastic products. It is often possible to recycle several types of plastics together (e.g. low- and high-density polyethylene and poly-propylene). However, polyvinylchloride (PVC) is processed differently and needs to be separated from other plastics for recycling. PVC comprises a significant proportion (30%) of medical plastics. There are fewer recyclers of PVC than other plastics, which tends to preclude recycling outside larger cities.

Hospital recycling programs do exist in Australia and New Zealand. One such hospital that has achieved great reductions in general waste and improvements in recycling is the Royal Brisbane. There are opportunities for recycling much more than cardboard, paper, plastics and glass. Electronic items, metalware (old beds etc.) and batteries can all be recycled in the larger Australian centres, yet this is not routine. A Melbourne metropolitan plastic recycling company is currently converting polypropylene surgical instrument wrap into plastic products such as boardwalks and outdoor furniture (http://www.replas.com.au). There have also been local Australian hospital pilot plastic recycling projects that take ampoules, syringes, intravenous cannula covers and surgical wrap to make plastic flooring, although these are in their infancy. In addition I have set up a pilot program to recycle PVC (oxygen masks and tubing and emptied intravenous fluid bags) into irrigation pipes, although this is also in its infancy.

Hospital waste is costly, both financially and environmentally, and will become more so with rising costs of oil-based products such as plastics and a potential price on carbon. Waste has been increasing at a greater rate than population during the past few decades with the move towards single-use products. Greater emphasis should be placed upon the reuse of medical items, despite the natural tension that exists between infection control and public health.

There are excellent Australian and international examples of greater recycling of hospital waste, but much remains to be achieved, perhaps by making waste accreditation a mandated component of hospital accreditation.

It remains to be seen if the ever-increasing tide of single-use items will be conquered.

Further information regarding hospital waste and sustainability can be found at www.dea.org.au and by viewing the Code Green clip at http://www.youtube.com/watch?v=nIdebt9a_iI