Medical Waste Disposal Research Articles

Managing Medical Wastes During the Covid-19 Pandemic in Nigeria

A pandemic disease poses great threats to humans and apparently, leading to a global crisis and challenge on the health, economic and other sectors of human endeavour. In order to minimize the devastating effects from pandemics such as the novel corona virus, effective management of ever increasing medical waste is pertinent. Recently, Nigeria has been reporting increasing number of cases from Covid-19 with increasing pressure mounted on the Government, healthcare systems and the populace in entirety. Owing to the high rate of infection from the corona virus, a more sophisticated method of managing the generated infectious is pertinent to mitigate the effects of the infectious medical waste accruing to the environment. More emphasis in the spread and management of covid-19 in Nigeria is focused on establishing testing centres, treatment centres and isolation facilities with little attention or no attention towards establishment of a safe disposal facilities for the infectious waste generated. This study has assessed effective management strategies for covid-19 associated medical wastes in Nigeria. Data for the study was majorly descriptive and adapted from secondary source through the Nigeria Centre for Disease Control (NCDC). Investigations from the study carried out reveals that Nigeria's foremost Environmental Regulatory body has no officially assigned dumpsite across the country for medical waste. Furthermore, the tertiary healthcare facilities across Nigeria's states has no safe and proper facilities for disposal of infectious medical waste. Challenges such as the various lackadaisical attitude and negligence of the populace towards covid-19 pandemic as well as poor enforcement of guidelines on infectious medical waste. In addition, the study recommends based on the findings, the use of Personal Protective Equipment (PPE) by waste collectors and the involvement of relevant stakeholders in the creation of environmental department to be supervised by Environmental Health Officers in all hospitals as a measure to ensure effective enforcement of the guidelines on safe disposal of infectious medical waste.

COVID-19: A review of protective measures

The coronavirus disease 2019 (COVID-19) started as a pneumonia of unknown etiology in 44 patients in the Wuhan city of China and has progressed into a pandemic affecting more than 4.7 million people to date. The morbidity, mortality, and socioeconomic consequences of the disease are grave. Personal protective measures taken by the general public and health-care providers along with the implementation of strategies, policies, and legislation at the state, national, and international levels are important to limit the community spread of COVID-19. Well-articulated protocols decrease confusion and increase the efficiency of the working staff, thus playing an important role in the protection of both the patients and health-care providers. In this review, we discuss the guidelines and protocols for the preventive measures to be implemented when dealing with patients in health-care establishments, especially with regard to performing imaging studies, surgeries, admission to the intensive care unit (ICU), disposal of medical waste, and the last rites of the body of the deceased.

Procesiranje i skladištenje krvnih komponenti u uslovima COVID-19 pandemije

The spread of the COVID-19 virus has a strong influence on blood collection, maintaining a stable supply of all blood components and the safety of the transfusion itself. SARS-CoV-2 has a long incubation period (1-14 days, on average 5-6 days, longest reported 24 days) and causes asymptomatic infection in a large number of patients, which is a great challenge in a recruitment of blood donors and achieving a safe transfusion. Precise recommendations and precautions have been adopted regarding the criteria for temporary refusal of blood donors during the COVID-19 pandemic, organization of mobile teams and collection sites, disposal of medical waste, examination of potential donors and mandatory body temperature measurement. Although transmission of COVID-19 via blood and blood components has not been demonstrated, some countries have also introduced mandatory NAT testing for SARS-CoV-2 as a part of blood screening testing. Also, proactive measures have been taken, such as temporary storage of blood in quarantine for 14 days after collection, while special attention is paid to efficient management of blood component stocks and development of a collection plan, in order to avoid shortage of certain blood components or their expiration. The first step in this regard is to revise the measures which have the aim for improving the usability of blood components, ie reducing waste of stocks, which primarily refers to the temporary extension of the shelf life of blood components. Extending the shelf life of erythrocytes (longer than 35 to 49 days, which is defined at the national level) should be considered as early as possible, because once a shortage of erythrocytes occurs, they will be issued long before the expiration date. Previous studies have not shown significant side effects of erythrocyte transfusion with extended shelf life, so it is possible to consider the flexibility of blood processing and erythrocyte storage conditions with mandatory internal process validation and component quality control. The shelf life of platelet concentrate should be extended from 5 days to 7 or even 8 days, with mandatory bacteriological testing or pathogen inactivation. Another option to increase the platelet supply for prophylactic purposes is to reduce the platelet dose by dividing the existing components. Frozen fresh plasma has the longest shelf life (up to 3 years), so maintaining stable reserves is much safer than for cellular components. Liquid plasma (never previously frozen) has a shelf life of 7-40 days, and can be used in conditions of reduced freezer capacity, shortage of staff working on blood processing or for the production of convalescent plasma. Pathogen inactivation of plasma and platelets allows 3-6 log reduction of SARS-CoV-2 and MERS-CoV. The decision to introduce some of the methods of pathogen inactivation should be made taking into account the costs and resources required for implementation. For countries that do not have pathogenic inactivation already in routine practice, its rapid introduction is a big task. For now, the risk of SARS-CoV-2 transmission through the blood appears to be very low, although our understanding of the virus and behavior during a pandemic will improve over time. In this regard, pathogen inactivation of convalescent plasma should also be considered.

Medical and technical aspects of activities at hospital departments of infectious diseases during the pandemic of the Coronavirus disease 2019 and other highly infectious diseases

Introduction. The article presents information on the activities of inpatient facilities for infectious diseases during the pandemic of the new coronavirus disease 2019, taking into account current regulatory documents. The authors reviewed the principles of hospital zoning and patient controlled movement in hospitals for infectious diseases. The paper deals with the organization of the admission departments and equipment of the diagnostic units of hospitals for infectious diseases, providing a graphical presentation of an individual isolation unit (Melzer box) including description of the control and management system for safe access to infectious units. The characteristics of engineering and communication systems, disposal of hazardous medical waste, catering, navigation systems, operational remote communication between doctors and patients, application of barcoding for patient identification and medical records are also discussed. The purpose of this paper was to: Identify the shortcomings of the existing regulatory framework concerning the management and organization of health care institutions that provide medical care to patients with the new coronavirus infection; Identify areas that require adjustments, given the modern requirements for high quality treatment, as well as to ensure epidemiological safety for medical staff and patients; Specify additional requirements for hospitals for infectious diseases, which should be taken into account when planning major repairs, reconstruction and construction of new medical facilities for providing health care during the pandemic of new coronavirus disease 2019 and other highly infectious infections.

Medical Waste Proper Disposal and Techniques - A Review of Multiple Devices

Every year municipal solid waste continues to grow as the US population expands. Municipal solid waste includes substances that pose a harmful risk for the environment such as medical waste or pharmaceutical agents. Health-care related waste increases annually by 15% and thus concerns for proper disposal of hazardous agents such as medical waste or pharmaceutical agents increases. It is important that these agents are disposed of properly to mitigate the chances of toxins and hazardous materials from tampering with the environment, and ultimately the US’s water supply. Additionally, medical waste can contribute to illicit drug abuse and potential overdoses. Methods such as flushing and disposing of these wastes in regular garbage are most common. However, medical waste disposal devices have been marketed to help reduce the risk of potential toxicities to the environment. These medical devices can be broken up into three categories: storage, sequestering agents, and immediate destruction devices. Sequestering agents are the most common devices within this review. The objective of this review is to highlight these different devices as well as describe what each can or cannot do.

Ways to Resolve Global Problem of Collection, Conveyance and Disposal of Hazardous Medical Wastes in Ukraine

This scientific paper studies the procedure and specific aspects of collection, conveyance and disposal of hazardous medical wastes in Ukraine. Drawing on analysis of the state of matters in the sphere of collection, conveyance and disposal of hazardous medical wastes in Ukraine, we proposed effective ways to resolve this problem. With a view to improve the procedure for collection, conveyance and disposal of hazardous medical wastes in Ukraine, we proposed, firstly, to strengthen public control over the state procurement with the help of “DoZor public”, an online platform, where everyone can provide a feedback to a state customer or supplier, society or law enforcement authorities regarding the conducted procurement procedure, discuss and evaluate the terms of a particular purchase, and analyze purchases of a particular customer. Secondly, insufficient control by the state also provokes emergence of such situations. In this context, it is expedient to lift the moratorium on inspections of business entities by the controlling bodies. It has been established that the main sources of generation of pharmaceutical and medical wastes in Ukraine are: medical waste from hospitals, health centers, health resorts, outpatient clinics, etc.; materials from laboratories and pharmaceutical manufacturing enterprises; tissues and body parts from surgical theaters; expired drug products; medical devices; leftover medicines in the form of liquid medicines, pills, solutions, etc. in a household setting; waste from pharmacies, pharmacy branches and pharmacy kiosks; packaging materials from drug products, etc. The author has investigated the main methods employed for destruction of poor-quality drugs in the form of solid products, powders (pills, capsules, granules, powders for injection), semisolid drugs (creams, gels, ointments) by means of encapsulation, inertization or high-temperature incineration.

Infection prevention and control measures in audiology practice within public healthcare facilities in KwaZulu-Natal province, South Africa.

BackgroundAudiologists have a clinical and ethical responsibility to create a working environment, designed to reduce the potential for cross-contamination or transmission of infections.ObjectivesTo describe the infection prevention and control (IPC) measures utilised and the opinions of audiologists and speech therapists, and audiologists (A/STAs) towards IPC in public healthcare facilities in KwaZulu-Natal province, South Africa.MethodA quantitative, descriptive survey was utilised and entailed completing an online questionnaire. The Cronbach’s alpha (0.82) indicated good internal consistency of the tool. Forty-nine A/STAs from 29 public healthcare facilities responded.ResultsMost participants (82%) followed a generic Department of Health policy on IPC, while 67% alluded to a discipline-specific policy. Participants had received training in infection control but indicated that further instruction was required for audiology-specific infection control procedures. Only 57% indicated that they ‘sometimes’ wore gloves with every patient during direct clinical contact. An association between the healthcare facility level and the wearing of gloves was found to be statistically significant (p = 0.025). Participants at regional and tertiary levels contended that gloves should be worn during most procedures versus those at district levels of care. While 96% washed their hands after each patient, only 76% washed their hands before each patient. Twenty-nine per cent indicated that they only ‘sometimes’ wore masks when in contact with patients with communicable diseases. Approximately one-third disinfected touch surfaces and toys, based on the clinician’s discretion. The majority (86%) of participants, however, always followed the correct protocol for medical waste disposal. Despite training and the availability of policies, some practitioners displayed poor IPC practices in terms of universal precautions, personal protective equipment, handwashing and sterilisation.ConclusionFurther education, training and awareness related to appropriate IPC measures are recommended for audiologists. It is envisaged that this will lead to more effective IPC measures in audiology practice thereby reducing the risk of infection transmission.

How blameless are hospitals in climate change? An example of a province in Turkey

Abstract Starting from the 1970s, the discussion about the negative effects of human activity on the world has accelerated and with a increasingly raised voice and it has been noted that the natural balance of our world was being altered. The World Health Organization has focused its policies and directives on strategies aimed on dealing with climate change (and its impact on human health), and diseases related to air pollution and implementing health-related sustainable development goals in climate friendly-hospitals. Hospitals exist to treat patients, but they also pollute the environment because hospitals consume a lot of energy and water and produce hazardous waste. These organizations need to work hard to improve their carbon footprints. The study investigated practices at 21 public hospitals in Konya, Turkey. Results show that domestic waste was on average 54.83 tons per year, medical waste was 33.59 tons per year and packing waste was 24.36 tons per year. It was determined that medical waste disposal costs on average of €26,800 per annum, and the amount of medical waste per bed was 1.15 kilograms per annum. According to 2014 medical waste data the average medical waste per bed of these hospitals in Konya province is less than the average in Turkish public hospitals, in which it is 1.18 kilograms per bed. The hospitals in our study were found to be especially inadequate at water management and did not pay much attention to green practices.

Medical Plastic Waste Disposal by Using in Bituminous Road Construction

The measure of plastic in the solid waste generated is increasing due to increase in factors such as urbanization, various development activities and changes in life style of humans which is leading to an unrestricted scattering on the landscape. Thus the disposal of these waste plastic has become a severe issue globally due to their non-biodegradability nature. Another area of concern is the deteriorating quality of roads due to the increase in traffic and their lower resistant’s to withstand adverse climatic conditions. Studies are being carried out to develop suitable alternatives for providing good, conventional road constructional materials for providing eco-friendly roads which have good design life. In this work, autoclaved medical plastic waste in the form of shredded syringes used in road construction is tested. The main objective of this work is to study how to use shredded Biomedical Plastic waste (BMPW) in Bituminous Mix and to compare the performance of the aggregate and bitumen when modified with bio-medical plastic waste. The results from the case studies showed improved properties for Plastic Coated Aggregate when compared to normal aggregates. There by showing that by using biomedical waste in bituminous road construction could bitterly change the quality of road and also the design life of bituminous roads by improving their properties.

Medical Waste Disposal Regulation in International Laws

Medical Waste Disposal Regulation in International Laws

Medical Waste Management : Technologies ANS Innovations

The problem of medical waste management is an issue that concerns not only experts since the amount of waste has a stable tendency to intensive growth. The research aims to study the status of medical waste management and analyze the approaches to its classification, taking into account the specific features of its formation and possible disposal. The article defines theoretical approaches to the analysis of the "medical waste" category and identifies the main directions of research in the field of medical waste management. Based on the analysis of scientific literature and an expert survey, the authors analyze the problems associated with the disposal of medical waste and the possible approaches to their solution. The authors propose a classification of medical waste and operations performed with it in health care centers.

Patterns of Sharps Handling and Disposal Among Insulin-Using Patients With Diabetes Mellitus

The objective of this study was to assess disposal patterns for "sharps" among a cohort of patients with diabetes mellitus (DM) receiving insulin therapy. A convenience sample of inpatients and outpatients was surveyed about how they disposed of sharps, how often they reused lancets and needles, and what education they had received about proper disposal. Safe disposal was defined as discarding sharps into a formal sharps or sealable container; otherwise, disposal was categorized as unsafe. Of 150 respondents, 56% were men and 75% were white. The mean (SD) age was 56 (15) years; duration of DM, 20 (13) years; and hemoglobin A1c, 8.1% (2.0%). Half the respondents reused a lancet two or more times, and 21% reused an insulin needle two or more times. Thirty-eight percent of respondents discarded lancets unsafely, and 33% discarded insulin needles unsafely, typically by throwing these items into household trash. Most respondents (75%) discarded insulin pens, vials, cartridges, insulin pump supplies, and continuous glucose monitor sensors into household trash. Most (64%) indicated that they had not received education on safe sharps-disposal practices, and 84% had never visited their municipal website for information on medical waste disposal. Approximately one-third of patients unsafely disposed of sharps. Unsafe disposal could cause millions of sharps to appear in the municipal solid waste stream, thereby posing a substantial public health hazard. Point-of-care patient education is important, but a broader public health campaign may be required.

Assessment of Temporary Community-Based Health Care Facilities During Arbaeenia Mass Gathering at Karbala, Iraq: Cross-Sectional Survey Study.

BackgroundArbaeenia mass gathering (MG) in Karbala, Iraq, is becoming one of the largest MGs in the world. The health care infrastructure in Iraq is inadequately prepared to serve the health needs of the millions of pilgrims.ObjectiveThis study aimed to describe the temporary health care facilities installed and run by the local community to provide health care services to Arbaeenia pilgrims in Karbala, Iraq.MethodsA survey was conducted in all community-based health care facilities located along part of Najaf to Karbala road within Karbala governorate. A structured questionnaire was answered through an interview with the workers and direct observation. Data were collected on staff profile, type of services provided, use of basic infection control measures, medical equipment, drugs and supplies, and the most commonly encountered medical problems.ResultsThe total number of health care facilities was 120, staffed by 659 workers. Only 18 (15.0%, 18/120) facilities were licensed, and 44.1% (53/120) of the workers were health professionals. The health care workers provided different services including dispensing drugs (370/1692, 21.87%), measuring blood pressure and blood sugar (350/1692, 20.69%), and caring for wounds and injuries (319/1692, 18.85%). Around 97% (116/120) health facilities provided services for musculoskeletal disorders and only 16.7% (20/120) provided services for injuries. The drugs available in the clinic were analgesics, drugs for gastrointestinal and respiratory diseases, and antibiotics, with an availability range of 13.3% to 100.0%. Infection control practices for individual protection, environmental sanitation, and medical waste disposal were available in a range of 18.1% to 100.0%.ConclusionsCommunity-based health care facilities experienced a profound shortage of trained human resources and medical supplies. They can significantly contribute to health services if they are adequately equipped and follow standardized operation procedures.

Assessment of Hospital Wastes Management Practices in Lagos, Nigeria, using Two Health Care Centres as Case Studies

Hospital wastes are highly infectious and can pose serious threat to human health. As the rate at which these wastes are generated is getting rapidly higher because of rapid urbanization and population growth, also the problem of disposal of these wastes is becoming more serious. It is of utmost importance that these wastes receive specialized treatment and management prior to their final disposal. Some of these wastes are mixed with household wastes, and the entire pile becomes a great public health hazard. Scavengers search through the piles for salable items, which they wash, repack and resell to the public, endangering their lives, and that of the entire public. Until recently, the management of medical wastes has received little attention despite their potential environmental hazards and public health risks. The collection, storage and disposal of medical wastes in Lagos are of growing environmental problem which needs immediate attention. This study was carried out to assess the current waste management practices in terms of type of wastes and quantities of waste generated in the healthcare facilities and the waste handling and disposal practices; also, to assess the level of awareness of health workers regarding hospital and clinical waste management. Two health care facilities in Lagos state were used as case studies. These hospitals are secondary facilities providing emergency, surgical, material and child health services. The methodology design was mainly of qualitative and involved physical observation, questionnaire administration, quantitative data collection procedures and manipulation, data analysis and interpretation. The findings showed that there was almost no knowledge of hospital waste management policy in the two health care facilities among the management staff, which seemed to confirm the premium on hospital wastes and their poor management.

Analisis Pemilihan Tempat Pembuangan Limbah Medis Menggunakan Metode Topsis

Various types of medical waste produced from service activities in hospitals can endanger and cause health problems, especially during collection, sorting, shelter, storage, transportation and destruction and final disposal. In terms of disposal of medical waste, most existing hospitals work with other companies in the processing and disposal of their medical waste because there is no official medical waste disposal site available. With the above problems, the researchers are interested in conducting a research process to assist the relevant agencies in finding a solution to determine the location of appropriate disposal of medical waste through the application of information technology. The method used in this study is the TOPSIS (Technique for Others Reference by Similarity to Ideal Solution) method, which is one method in the Decision Support System (SPK). Based on the results and previous discussion, it can be concluded that Mandoge is the main choice in choosing the right place as a place for disposal of medical waste because it has the necessary criteria. Therefore the application of the topsis method can help determine good alternatives in a decision-making system for selecting the best Medical Waste disposal sites.

واقع إدارة النفايات الطبية في عيادات الأسنان دراسة حالة: عيادة الأسنان في محافظة خانيونس

هدفت الدراسة إلى تقييم واقع إدارة النفايات الطبية في عيادات الأسنان بمحافظة خانيونس (دراسة حالة) من حيث عمليات الفرز للنفايات الطبية الخطرة، والجمع وهي عملية جمع النفايات في أكياس مغلقة بإحكام عند امتلائها، والنقل من خلال شاحنات النقل الخاصة بنقل النفايات الطبية والتخلص منها، وقام الباحثان باستخدام منهجية المقابلة الميدانية والملاحظة المباشرة للعيادة، وطرح مجموعة من الأسئلة على العاملين في العيادة، وكان من أهم نتائج الدراسة أنه لا توجد عملية فرز للنفايات الطبية بطريقة سليمة حيث تتم بطريقة عشوائية، وعدم الالتزام التعليمات لقوانين منظمة الصحة العالمية الخاصة بإدارة النفايات بطريقة سليمة ويتم التخلص منها عن طريق المحارق التابعة لوزارة الصحة بمحافظات غزة. وأوصت الدراسة بضرورة وجود نظام خاص بفرزالنفايات الطبيةالخطرة عن النفاياتالطبيةغيرالخطرةمن مصدر انتاجها وبالطرق السليمة، وتعزيز وضع تشريعات كسياسات لإدارةالنفايات الصحيةمن أجل السلامةالصحية، وزيادة الوعي لدى العاملين بالمؤسسات الصحية حول مفهوم إدارة النفايات الطبية وخطورتها وتوفير سيارات نقل خاصة لنقلها

Assessment of Temporary Medical Clinics During the Arbaeenia Mass Gathering at Al-Karkh, Baghdad, Iraq, in 2014: Cross-Sectional Study.

BackgroundDuring mass gatherings, public health services and other medical services should be planned to protect attendees and people living around the venue to minimize the risk of disease transmission. These services are essential components of adequate planning for mass gatherings. The Arbaeenia mass gathering signifies the remembrance of the death of Imam Hussain, celebrated by Shiite Muslims, and takes place in Karbala, which is a city in southern Iraq. This annual mass gathering is attended by millions of people from within and outside Iraq.ObjectiveThis study aimed to map the availability of medical supplies, equipment, and instruments and the health workforce at the temporary clinics located in Al-Karkh, Baghdad, Iraq, in 2014.MethodsThis assessment was conducted on the temporary clinics that served the masses walking from Baghdad to Karbala. These clinics were set up by governmental and nongovernmental organizations (NGOs) and some faith-based civil society organizations, locally known as mawakib. We developed a checklist to collect information on clinic location, affiliation, availability of safe water and electricity, health personnel, availability of basic medical equipment and instruments, drugs and other supplies, and average daily number of patients seen by the clinic.ResultsA total of 30 temporary clinics were assessed: 18 clinics were set up by the Ministry of Health of Iraq and 12 by other governmental organizations and NGOs. The clinics were staffed by a total of 44 health care workers. The health workers served 16,205 persons per day, an average of 540 persons per clinic, and 368 persons per health care worker per day. The majority of clinics (63% [19/30]-100% [30/30]) had basic medical diagnostic equipment. Almost all clinics had symptom relief medications (87% [26/30]-100% [30/30]). Drugs for diabetes and hypertension were available in almost half of the clinics. The majority of clinics had personal hygiene supplies and environmental sanitation detergents (78%-90%), and approximately half of the clinics had medical waste disposal supplies. Instruments for cleansing and dressing wounds and injuries were available in almost all clinics (97%), but only 4 clinics had surgical sterilization instruments.ConclusionsAlthough temporary clinics were relatively equipped with basic medical supplies, equipment, and instruments for personal medical services, the health workforce was insufficient, given the number of individuals seeking care, and only limited public health service, personal infection control, and supplies were available at the clinics.

ROLE OF GEOGRAPHIC INFORMATION SYSTEMS (GIS) IN LOCATING THE MOST SUITABLE SITES FOR HAZARDOUS MEDICAL WASTE DUMPSTERS (CASE STUDY: SOHAG CITY)

Hazardous medical waste is a very serious source on human health and environmental system،for its highly hazardous chemicals، organic، and radiant content. The disposal process of hazardous medical waste is carried out in several stages: collection، sorting، storage، transportation and treatment، and ending with the final safe disposal. The final disposal phase is an important stage from these stages. The landfill or burial is one of the most important methods of waste final disposal process. This is done by using waste dumpsters with specific specifications prepared for this purpose. It is important in this regard to determine the location of sanitary dumpsters، which need to determine their places accurately، in a way that does not adversely affect the environment، and provide adequate safety means، by using scientific methods as a substitute for the traditional means of self-experience and decision-makers experience. From here the study importance in Sohag city،where Sohag is one of the areas that suffer from medical waste management and disposal problem in accordance with the principles and standards of health and safety the public، Where the reliance on the means of burning only for the final disposal of tit at the complex of incinerators in (Kawther) area، Sohag city، which is not contain any sites for the burial of hazardous medical waste.

Review of medical waste management in Jordanian health care organisations

Background/Aims Medical waste, or clinical waste, is generated in hospitals, clinics, and pharmaceutical manufacturing as a result of the diagnosis, treatment and medicine that is being produced across the healthcare system. This waste can have a severe effect on both the environment and population health. Overall, between 75% and 90% of the waste produced by healthcare providers is non-risk general waste or domestic waste. It is therefore mandatory for healthcare organisations to have an effective medical waste management plan to eliminate real health and environmental hazards. Methods This article critically reviews literature that investigates the administrative procedures and collection protocols regarding medical waste. Results Several problems occur during the disposal of medical waste in hospitals in Jordan. The research demonstrates how effective waste management can reduce health risks and protect the environment. Conclusion Overall, there is a poor handling of medical waste, which extends to a lack of regulations that govern medical waste procedure.

Ethics of limb disposal: dignity and the medical waste stockpiling scandal

We draw on the concept of dignity to consider the ethics of the disposal of amputated limbs. The ethics of the management and disposal of human tissue has been subject...