The Influence of Pandemic COVID-19 on Hazardous Waste Management from Hospital A in Yogyakarta

The condition of COVID-19 pandemic led to a high generation of medical waste through hospital activity. This study aimed to analye the hazardous waste management during the pandemic at Hospital A in Yogyakarta. Dynamic system modelling applications by considering the technical, financial, and environmental aspects using the Vensim PLE with the stock-flow diagram. The model simulation results in this study indicate an increase in technical, financial, and environmental aspects during the pandemic. The technical and financial aspect shows that the generation and transportation of waste increased during the pandemic reaching 9.36%. In the technical aspect, hazardous waste generation produced 11,756 kg/year. Then, the financial aspect shows that the costs incurred for transporting waste increased during the pandemic, reaching IDR109,860,000/year. The financial aspect also indicates that the fees received by hospital A in Yogyakarta from recycling waste increased until IDR3,232,900/year. The environmental aspect shows that CO2 emissions released into the air due to the transportation of waste during the pandemic experienced a stable condition, it is 5,445.44 kgCO2 per year, and CO2 emissions stored due to the recycling of plastic infusion bottle waste increased by 4,021.73 kgCO2 per year.


Introduction
The Severe Acute Respiratory syndrome (SARS) virus family and several other types of common cold viruses are related to the Corona Virus Disease-19 (COVID-19) [1].The COVID-19 epidemy caused medical hazardous waste in hospitals to accumulate along with the rise in COVID-19 cases [2].Official data on hazardous waste generation for the period of March to May 2020, shows that Yogyakarta province, Indonesia, is the second most area generating hazardous waste with average number 400 tons/month.[3].In Indonesia, like in many other countries, hazardous waste is defined as items that cannot be reused because they could potentially spread the COVID-19 virus, either because these items have come into contact with patients or staff at service facilities or healthcare facilities that treat COVID-19 patients or because they have been contaminated with infectious substances [4].COVID-19 wastes are classified as infectious medical wastes; moreover, these wastes are hazardous because they threaten the environment and living organisms if they are not appropriately managed.Therefore, hospitals must have proper hazardous waste management procedures in place to prevent the spread in the environment and endanger the public's health as well as that of healthcare and non-healthcare employees.[4] [5] [6] .Controlling hazardous waste therefore is a crucial concern for hospitals and dynamic modelling may aide in the efficient management of hazardous waste during the pandemic [7].For example, the proposed bi-objective model is solved using fuzzy goal programming, and the performance of the proposed model and solution approach is evaluated using data pertinent to 13 nodes of medical waste production at a specific location west of tehran [6].Also, dynamic modeling system project future scenarios, helping to assess and provide information for policy making (such as phase-in period) and/or influence the management of hazardous waste [8] ; [9] ; [10].
For hospitals to benefit from hazardous waste management system, policies connected to their implementation of hazardous material handling protocols must take a number of factors into account, such as technical, economical, and environmental elements of the management of hazardous waste.In 1257 (2023) 012014 IOP Publishing doi:10.1088/1755-1315/1257/1/012014 2 this study, we developed a multi-parameter dynamic waste management system model for the hospital A in Yogyakarta and simulated management scenarios during the COVID-19 pandemic in 2020 to 2021.The goal of this study was to evaluate the performance/effectiveness of that model under different scenarios.The results of this study should be relevant to other hospitals without proper hazardous waste management protocols, not just during another pandemic but potential during regular operation times.

Research Methods
This study employs a descriptive quantitative methodology based on primary questionnaire data and secondary data collected by the hospital as required by Indonesian national standards before (january 2019-february 2020) and during (march 2020 -March 2021) the pandemic.The dynamic system model was constructed using causal stock-flow diagram-based methodology.
The primary data was acquired from observations and interviews with sanitation employees, cleaning services, and Environmental Health & Safety supervisor.Also, data on waste accumulation over time was recorded following the methods in [11].In general, hazardous hospital waste is collected by sanitarians from each room and building, collected in a warehouse before transport to disposal.It was in the warehouse where the primary sampling was done.Secondary data includes the number of hospital beds and the total number of patients at hospital, also the kind of services that provide at the hospital.
The model was constructed using Vensim PLE 8.2 software and a stock-flow diagram-based methodology.A stock-flow diagram is a graphical representation of a process model that reveals the interrelationships between variables based on the influence of time [7].The core elements in the dynamic system model, according to [7] and [12], are arranged based on several variable categories; (i) rate/flow variables that show the rate of system activity in each time period for variables with constant values; (ii) level/stock variables that show the results of accumulation in the system under the influence of time; (iii) arrows that show the relationship between variables; and (iv) variables/converters that provide other causes that affect the model's structure.The steps involved in building a model using vensim are as follows [13] Parameters that influence hazardous waste generation from hospital A are number of patient served, kind of treatment provided by the hospital, and also the COVID-19 cases person per day.Besides, hazardous waste generation can impact financial and environmental aspects of monthly amount.Then environmental aspect could influence the global warming potential, for instance by moving the waste from this source into the recycling plant treatment.But the relation between this research with financial aspect is this cost that hospital should pay or value that could taken by manage hazardous waste well.
Model should verify and validate to make sure it went well.Verification is the process of comparing the model structure created in software to the model equations implemented in software; this model verification does not require information regarding the model's output [14].The equations (units) and structure of the constructed model will be verified in dynamic system modeling.Based on the results of model verification, both the model's equations and structure are error-free, so the constructed model ready to simulate properly.
Validation on modelling is the process of assessing the compatibility between the predictions of model simulation results and actual extant data [15].Between 2020 and 2021, the quantity of the patients will be validated.The results of the average error value was less than 30%, or 0.000097.It indicates that the constructed model is asserted to be quantitatively valid.Model validation is essential to guarantee the accuracy of the created model system, and the truth is that the simulation results of the model correspond to the actual situation.The performance validation test and the AME (Absolute Mean Error) validation test can be used to validate a model.The acceptable deviation limit is 30% or less.The AME equation is represented by formula (1).

Result
The patient growth rate is used as one of the model dynamics that the constructed model can meet the existing system conditions [7].Table 1 displays the growth rate of patients during the COVID-19 pandemic.That indicates the number of patients served by both outpatient care and hospitalization services increased.Out-patient care is the services from hospital that patient come and check regularly their health in one day.Then hospitalization is services that make patient should take few days or more to take care at the hospital and make sure all of the symptom was over.These two kind services periodically generate hazardous waste from medical waste which is should be managed well.Because, if those waste unmanaged it can be potential spreading the new viruses at least at the hospital.
The number of Out-patient care services increased by 23.2%, while hospitalization services increased by 7%.This increasing number of patients is one of the causes of COVID-19 cases from 2020 to 2021.The hospital could see an increase in the number of patients that get treatments, COVID-19 isolation treatments, and COVID-19 screening via antigen and PCR (polymerase chain reaction) test.COVID-19 become a pandemic since the case always gain everyday.

Hazardous waste generation
Solid waste from medical sector consist of two categories : infectious and non-infectious.This research focus in infectious waste from facility and services.Kind of services that provide by this hospital such as emergency room, outcare services facilities, and hospitalization room.This research take sample everyday from each room that produce hazardous waste from medical waste.
Generation of hazardous waste from primary sampling found that the Outpatient care services generate 20.67 kg/day.The average amount of hazardous waste produce by hospitalization services is 21.5 kg/day.Hospitalization services generate more hazardous waste than Outpatient care services due to the condition that hospitalization services provide routinity treatment to patients for a certain amount of time per day, whereas Outpatient care services provide minimum service to patients.Use of instruments that can become contaminated with a patient's body fluids [16].

Technical aspect
The technical aspects discuss the number of waste generated by hospital activities.It counted the primary data and the data from several patients that served during the period.Hazardous waste generation shows an increasing number before the pandemic until the pandemic (2020 to 2021), from 10,749 kg/year to 11,756 kg/year (Table 2).The pandemic conditions have made changes in this business.An increasing number of hazardous waste is generated linearly with the generation of the patient serviced by the hospital: the more patients, the higher the hazardous waste produced.An additional number of patients because of COVID-19 cases is significantly increased.The number of patients receiving treatment will undoubtedly increase, as will people who come to test for COVID-19 analysis.This waste is collected daily by sanitarians and gets sprayed with disinfectants to remove potential pathogens.Then hazardous waste will be collected in a temporary hazardous waste warehouse for two days, and then it will be transported to the recycled waste sector.

Financial aspect
Financial aspects talk about the cost and income that hospital A manages.The cost that should be paid is from waste transportation every two days.Then the income from waste management came from selling the recycled waste by the hospital.The cost of transporting hazardous waste before the pandemic reached IDR 100,456,000/year.However, those numbers are getting more in pandemic conditions, and in 2021, transportation costs will reach IDR109,860,000/year.These numbers are counted by the amount of hazardous waste generation in kilograms.Besides transportation, the hospital already separates the waste from bottle infusion waste, which could be recycled.It obtained IDR2,956,160 before and IDR3,232,900 during the pandemic (Table 2).Because of that effort, the hospital can save more money, around IDR2,740.It could be an effort that hospital A was done to save the environment and mitigate those wastes not contaminated by hazardous waste.

Environmental aspect
Environmental aspect on this research, discuss about the by product that produce from hazardous waste management at the hospital A. This scope about transport activity for hazardous waste.According to the observation result, transportation was done every two days as rules in Indonesia.Hospital A using the vendor to transport their waste.Because of that, there are emission from the vehicle that released into the air.This research's environmental aspect discusses the by-product of hazardous waste management at the hospital A. This scope is about transport activity for hazardous waste.According to the observation result, transportation was done every two days as rules.Hospital A uses the vendor to transport their waste.Because of that, there are emissions from the vehicle that are released into the air.Emissions from the vehicles release CO2 into the air.It is known that it could be high pollution for the environment and potentially make a global warming phenomenon.CO2 is one of the greenhouse gas emissions that increases the earth's average temperatures.Because of that, we should know how much transportation of hazardous waste contributes to global warming.Then we could analyze if it is reduced to mitigate the risk.
The simulation results on environmental aspects show that CO2 emissions are also released into the air from hazardous waste transportation activities.The vehicle's consumption of fuel generates it.Each transportation that is done every two days produces emissions in CO2 form.Besides that, CO2 emissions are also stored due to recycling infusion bottle waste.It will increase along with the weight of hazardous waste that could be recycled.As shown in Table 2, CO2 emissions from the transportation of hazardous waste have a constant yield of 5,445 kgCO2/year both before and during the pandemic.This study's limitation is that there needed to be more data to input and run in the model.
CO2 emissions are also stored and not released into the air due to waste recycling activities.The hospital A already separates the recycling and unrecycled medical waste.This recycling waste is from bottle infuse waste in hospitalization services.From 2020 to 2021, there were 344.26 kgCO2/year.Activities to minimize the infusion of plastic waste by recycling include activities that contribute to reducing and lowering CO2 emission levels released into the air.

Conclusion
Based on the simulation results of the dynamic system modeling, it is known that the technical, financial, and environmental components of the management of hazardous waste are interrelated.Technical, financial, and environmental aspects increase by 9.36% from 2020 to 2021 during the COVID-19 pandemic.Technically, hazardous waste generation produced 11,756 kg/year.The financial aspect reveals that, during the pandemic, the cost of transporting refuse increased to IDR109,860,00/year.The financial aspect also indicates that Hospital's income from recycling refuse increased toIDR3,322,900/year.CO2 emissions released into the air due to waste transportation during the pandemic remained stable at 5,445.44 kgCO2/year, while CO2 emissions stored due to the recycling of plastic infusion bottle waste rose by 4,021.73kgCO2/year

1 Figure 1
Figure 1 Stock-flow diagram that influence the generation of hazardous waste in hospitals during COVID-19

Table 1
Generation of Hazardous waste and patients grow rate during pandemic

Table 1
[16]s the hazardous waste generation from out-patient care services 0.09 kg/person/day and hospitalization services 2.39 kg/person/day.Besides, these data taken by Outpatient care services with average 223 patients/day and Hospitalization services with an average of 9 patients/day.According to the data, We get the average amount of hazardous waste generated per patient each day is 2.48 kg/day.Meanwhile in Bandung and Cimahi City Hospitals, they generate hazardous waste around 0.08 and 2.18 kg/patients/day[16].Compare to that research, hospital generates (Table1) significantly more hazardous waste both from out-patient care and hospitalization services.The number of patients each day and the number of medical operations performed are variables that can influence the hazardous waste results in hospitals.[16][17].

Table 2
Non pandemic and pandemic condition of hazardous waste at Hospital services