Medical waste management at the Oncology Institute of Vojvodina: possibilities of successful implementation of medical waste regulation in Serbia

Introduction

Until 2009 there was no medical waste management protocol for health institutions in Serbia. Before 2009, medical waste was often mixed with municipal solid waste and commonly disposed of in municipal landfill sites. Information about segregation, transportation and disposal of different types of medical waste from healthcare facilities (HCFs) was very limited and unknown. Improper disposal of medical waste may pose a significant risk to human health and the environment. Some of the problems arising from poor management of medical waste may include damage to humans by sharp instruments, diseases transmitted to humans by infectious agents, and contamination of the environment by toxic and hazardous chemicals (Yong-Chul et al., 2006). The World Health Organization (WHO) provided HCFs with comprehensive guidelines on safe, efficent and environmentally safe methods of healthcare waste handling and disposal (Prüss et al., 1999). In order to advance medical waste management in HCFs, several previous studies in developing countries indicated the importance of a national regulatory framework (Phengxay et al., 2005; Shinee et al., 2008), a sound internal management system and training programme for related personnel (Da Silva et al., 2005), estimation of the healthcare waste generation rate (Tsakona et al., 2007) and appropriate techniques for disposal (Diaz et al., 2005). The Ministry of Environmental Protection and Ministry of Health share responsibility for medical waste management in Serbia. A national waste management strategy was adopted in 2003 and a master plan for hazardous medical waste management in Serbia was adopted in 2005 (and accredited in 2009) within the European Agency for Reconstruction. According to this plan, 78 centres for medical waste treatment were formed and distributed in 28 administrative districts in Serbia. HCFs were equipped with autoclaves (capacity: 165 kg/8 h) for the sterilisation of infective medical waste, as well as with crushers for the reduction of the newly formed, sterile non-hazardous waste. Fifty-four institutions are fully equipped for the treatment of their own infectious medical waste: 15 institutions received crushers to minimise the amount of medical waste and 2 institutions were provided with vehicles for medical waste transport, and serve as central waste treatment facilities; other health facilities serve as local waste treatment facilities. The above plan is the most efficient and most effective method for the implementation of the waste management protocol in most of health facilities in the Republic of Serbia. The Oncology Institute of Vojvodina is the first institution in Vojvodina, and one of the first institutions in Serbia, to implement the recommended medical waste management protocol and was included in the national waste management strategy in 2009.

The present study aimed to analyse the process of medical waste generation, performance and the possibilities of implementing and improving the medical waste management protocol at the Oncology Institute of Vojvodina.

Materials and methods

The Oncology Institute of Vojvodina has 6 organisation units with a total of 239 beds. This institution is the only oncology institution in the entire region of Vojvodina and services a population of 2 million people.

A retrospective-prospective study analysed the production of medical waste in the period from April 2009 until April 2011. The first cycle was the period of analysis in the first year from April 2009 to April 2010; the second cycle was the one-year period from April 2010 to April 2011. Data were gathered through an observational checklist and by interviews with key personnel in charge of medical waste management. The observation included the following categories: segregation practice; storage; internal and external transportation; treatment and disposal of different categories of healthcare waste; occupational safety issues; and the type and amount of medical waste generated. The waste generation rate was calculated on a weight basis by measuring the waste produced after transportation. In addition, observation of departments, equipment, storage locations, handling practices and records of the handling process was also undertaken in order to verify the data.

Results and discussion

Medical waste disposal is performed in all departments of the Oncology Institute of Vojvodina, according to the national guidelines for safe medical waste management.

The segregation of medical waste includes separation and storage at the site of generation into plastic bags and plastic containers according to categories or groups defined by medical waste classification. The use of informative posters about the different categories of medical waste near the storage area is essential to warn an individual about the storage of hazardous waste that may be harmful to human health (Lalji et al., 2008), and they were displayed in all departments where medical waste was produced and stored.

At the Oncology Institute of Vojvodina various types of hazardous medical waste are produced on a daily basis, for example infectious waste, pathological waste, chemical waste, pharmaceutical waste, sharps, pressurised containers and radioactive waste.

Infectious medical waste (e.g. cultures and accessories from microbiological laboratories; equipment parts; supplies that come into contact with blood or patient secretions, or that have been used in surgical and protective procedures, bandaging wounds and autopsies; waste from the dialysis department; gloves and other disposable supplies) is stored in yellow bags, boxes or containers, placed in temporary storage in the Institute’s backyard, autoclaved and disposed of at the city’s landfill site.

A significant amount of pathological waste is generated daily by the Department of Oncological Surgery, including tissue and organs removed during surgery and biopsies, as well as blood and bodily fluids. These types of waste are separated, marked, packed in brown plastic bags and stored securely in freezers for temporary storage. Afterwards, according to current legislation, it has to be incinerated.

Pharmaceutical waste generated at the Oncology Institute of Vojvodina includes expired medications; unused drugs; spilled and contaminated drugs used during anesthetic procedures, as well as those used intra- and post-operatively; cytotoxic medical waste; heavy metals; gloves; masks; catheters; swabs; gauze; and other supporting material. Pharmaceutical waste is classified, put in red boxes or containers, properly stored in the pharmacy, and burned or disposed of to landfill. The particular procedure for the removal and destruction for each type of pharmaceutical waste will wait until final decision is made through national strategy for waste management.

Sharp objects (needles, lancets, scalpels, syringes, intravenous systems, etc.) are put in boxes at the site of generation and autoclaved daily before being disposed of in yellow plastic bags.

Chemical waste (which includes discarded solid, liquid or gaseous chemicals, and pressurised containers with antibiotics, disinfectants or corticosteroids as active substances in the form of aerosols) is put in red containers and treated in the same way as pharmaceutical waste.

General, non-hazardous waste is mostly segregated in black bags and disposed to landfill; however, a small amount is put in green bags and recycled.

Radioactive waste generated by the Department of Nuclear Medicine and Positron Emission Tomography (PET) Center is stored in red metal containers until the activity falls below the level of natural photons. Once that has occurred, it is treated like other medical waste.

The removal of medical waste from the departments takes place three times a day. Waste is them t stored temporarily in the local waste treatment facility, which is located in the backyard of the Institute. Once a week the waste is removed by City Sanitation Service to be incinerated; general waste is removed to the city’s landfill. The WHO recommend that the assortment of disposal methods should be based on local protocols (Prüss et al., 1999). However, the advantages of the formation of centralised regional disposal facilities include superior cost-effectiveness for larger units, easier disposal on a regional basis, better monitoring by the government and enhanced assurance of more environmentally-friendly operations.

Nevertheless, at the Institute, special containers with proper bio-hazard symbols are used, with special apparatuses for collection and transport, and special approved routes and times for collection and transport are determined. Control checks of the biohazard type, generation rate and management procedures are performed daily.

In a waste management plan it is crucial to determine the average quantity and type of waste generated at a HCF on a daily basis. The average annual waste generation rate at the Oncology Institute of Vojvodina is 10,545 kg, which corresponds to biohazard generation of 0.17 kg/bed/day. During the period analysed in 2009 medical waste generation rate was 8,913.9 kg, in 2010 it was 9,324.2 kg and in 2011 it was 3,696.04 kg. In Serbia, the average generation of medical waste in hospitals is 9,600 tonnes per year, which corresponds to 1.8 kg/bed/day—the average production of medical waste in hospitals in Eastern Europe (1.3–3 kg/bed/day). The amount of medical waste generated by the Oncology Institute of Vojvodina was, in general, coherent with the assortment of data from several preceding studies in developing countries, including: 0.16 kg/bed/day biohazard production in Croatia (Marinković et al., 2008), 0.68 kg/bed/day in Turkey (Birpinar et al., 2009), 0.5–2.2 kg/bed/day in Jordan (Abdulla et al., 2008), 0.41 kg/bed/day in Thailand (Danchaivijitrmd et al., 2005), 3.86 kg/bed/day in Taiwan (Jang et al., 2006), 2.6 kg/bed/day in Poland (Gluszynski, 1999), 0.25 kg/bed/day in Japan (Shaprio et al., 2003), 0.48 kg/bed/day in Mauritius (Mohee, 2005) and 1.22 kg/bed/day in China (Gai et al., 2010). According to the WHO recommendations the quantity of healthcare waste generated is usually about 10–25% of the total waste generated at a HCF (Prüss et al., 1999). Most of the waste generated at the Oncology Institute of Vojvodina is general waste comprising 23% of total waste.

We analysed the medical waste generation rate on a daily basis over two years to determine monthly and annual variations. Distribution values are mostly within the normal distribution (P) for all months of both cycles, meaning that the daily variations of mean values of the quantities of biohazard did not deviate significantly from each other. Larger values of the coefficient of variation (CV) indicate the heterogeneity of medical waste produced during the different months. This means that during some months there was a big difference between the daily amount of medical waste. Based on the graphic representation of confidence intervals, presented in the form of elipses in Figure 1, it is possible to observe the mutual position and characteristics of each of the 12-monthly quantities of waste over the 2 years observed.

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Figure 1.

Confidence intervals (numbers) of average daily quantities of medical waste generated in the two years observed. Each number represents the month of the year: January (1) February (2), March (3) April (4) May (5) June (6) July (7) August (8); September (9), October (10), November (11), December (12). God1-first year; god2-second year.

It is obvious from Figure 1 that the lowest production of medical waste in the first year was in January and the greatest production was in April. The reason for April 2009 having the largest waste production could be the fact that this was the first month following the implementation of the medical waste management, so the waste that had been produced before the implementation of the system was included in the waste from April 2009. Another possible cause might be an improper manner of collection, segregation and disposal of waste by staff during the adjustment period following the newly introduced system. The number of admissions, diagnostic procedures and interventions in that period may also cause the rate to be higher. In the second year, August 2010 had the lowest amount of generated medical waste and the highest amount in March 2011. The low value found in August may be because the number of surgical procedures in August is lower as a result of fewer patients being admitted, as well as the vacation period.

Calculating Mahalanobis distance, we compared the average daily volume of waste generated per month for both years observed (Figure 2.). Length indicates the minimal distance between December and November (0.03) (less), and the maximal distance between June and January (0.97)(moderate). The greater the distance is between two months, the more diverse the amount of waste generated in two months and vice versa. Based on the average daily value of generated work per month (during two-year period), it was possible to group the months as follows:

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Figure 2.

Distances between an average daily volume of waste generated per month for both years observed. Each number represents the month of the year: January(1), February(2), March(3), April(4), May(5), June(6), July(7), August(8), September(9), October(10), November(11), December(12).

The results obtained clearly show that the way that healthcare waste management was done over the observed period could be used to establish strategies for the organisation of waste removal services, containers supplied for the removal of medical waste and to determine the personnel responsible for waste removal.

It can be used as a model of the organisation and planning of healthcare waste management in other institutions. This concept can also serve as a predictor of the medical waste removal strategy in emergency situations.

The coefficient of discrimination indicates that the main contribution to the discrimination between the average generated monthlymedical waste was during the first observed year (0.74) versus the second year (0.21). This shows that even between months that have similar medical waste generation, the rate of difference can vary for comparable periods. After establishing the fact that there was a significant difference between these groups in over both years, we analysed the characteristics of these groups and whether the amount of waste in a certain category was higher or lower in length compared with the central tendency. The fact that P = 0.000, discriminant analysis means that there were clear limits between groups by volume, which means that the characteristics of each group could be specified. The status of each subgroup mostly defines the first year because of the contribution of the characteristic features (77.89%) followed by the second year (22.11%). The homogeneity of group 1 was 61.20%, for group 2 it was 61.96% and for group 3 it was 61.11%. Group 1 had 112 out of 183 days where the homogeneity of daily waste was 61.2% (higher). This means that 71 daily values had characteristics different from the group. According to the characteristics of group 2, 57 out of 92 daily values had 62.0% (higher) homogeneity because 35 daily values had characteristics different from the group. In group 3, 55 out of 90 daily values showed homogeneity of 61.1% (higher) because 35 daily values have characteristics different in the group.

This allows the conclusion to be made that daily value characteristics are similar (e.g. to group 1) and they could belong to an unknown group; however, it could be expected, with a reliability of 61.2%, that it belongs to group 1, which, again, makes the same prediction, regardless of the fact that, according to the characteristics, it should belong to be group 2.

Figure 3 shows the difference between the two years by the amount of waste generated in 2009 versus 2010 and 2011. Healthcare waste generation depends on numerous factors, such as the established waste management methods, the type of healthcare establishment, hospital specialisation, the proportion of reusable items and the number of patients treated on a daily basis (Cheng et al., 2009; Da Saliva et al., 2005). According to Prüss et al. (1999), the amount of medical waste generated depends primarily on the size and type of healthcare facilities, which, in turn, correlates with the level of national income and developement.

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Figure 3.

Waste generation rate over the observed two-year period.

An environmental management system and quality management is essential for each system that requires quality control and to reduce the financial costs. Institutions implement initiatives to improve environmental performance (such as an economic management system) in the processing of waste and show a high ability to reduce financial resources by introducting their own quality control management of medical waste.

The Ministry of Environmental Management in Serbia has limited financial resources for environmental management, hence it is unable to monitor and confirm the amount of hazardous medical waste by certain methods. As the removal of medical waste is an obligatory part of financial expenditures for medical institutions, certification (ISO 14001:2004) offers more conservative financial expenses.

Conclusion

The Oncology Institute of Vojvodina introduced a modern environmental management system for safe medical waste removal in accordance with legislation and international standards. There were no recorded irregularities in the application of procedures of medical waste removal. The amount of medical waste generated corresponds to values of generated in other healthcare facilities in eastern Europe. There was a difference in the monthly waste generation rate in one year and in the production of waste between the two observed years.

The results show that the methods for the safe management of medical waste were acceptable, affordable and economically justifable, and could be implemented in the institution, significantly contributing to protect employees’ health, and providing safer and better patient care, improved health of general population and the quality of business of the HCF.