Current Perspectives on Biomedical Waste Management: Rules,Conventions and Treatment Technologies

Unregulated biomedical waste management (BMWM) is a public health problem. This has posed a grave threat to not only human health and safety but also to the environment for the current and future generations. Safe and reliable methods for handling of biomedical waste (BMW) are of paramount importance. Effective BMWM is not only a legal necessity but also a social responsibility. This article reviews the current perspectives on BMWM and rules, conventions and the treatment technologies used worldwide. BMWM should ideally be the subject of a national strategy with dedicated infrastructure, cradle-to-grave legislation, competent regulatory authority and trained personnel. Improving the management of biomedical waste begins with waste minimisation. These standards, norms and rules on BMWM in a country regulate the disposal of various categories of BMW to ensure the safety of the health-care workers, patients, public and environment. Furthermore, developing models for the monitoring of hospital health-care waste practices and research into non-burn eco-friendly sustainable technologies, recycling and polyvinyl chloride-free devices will go in long way for safe carbon environment. Globally, greater research in BMWM is warranted to understand its growing field of public health importance.     

Biomedical waste disposal practices among healthcare workers during COVID-19 pandemic in secondary and tertiary care facilities of Tamil Nadu

PurposeThe ongoing COVID-19 crisis has drastically changed the practice of biomedical waste (BMW) generation and management. Studies venturing into the facility level preparedness at various levels of healthcare delivery during pandemic situation is the need of the hour. Hence, we did this study to assess the BMW disposal practices amongst secondary and tertiary health facilities during COVID-19 pandemic in Tamil Nadu.Materials and methodsThis cross-sectional survey was conducted amongst doctors, nurses and allied healthcare staffs across various departments in 18 public health facilities across six districts of Tamil Nadu. Multivariable logistic regression analysis was done based on the random-intercept model to assess the determinants of BMW disposal practices. The effect size was reported as adjusted odds ratio (aOR) with 95% confidence interval (CI).ResultsIn total, 2593 BMW disposal observations were made. During nearly three-fourth of the observations (73%), the BMW was disposed of appropriately. Nurses (aOR ?= ?1.54; 95%CI: 1.06–2.23) and doctors (aOR ?= ?1.60; 95%CI: 1.05–2.45), healthcare workers in Paediatrics department (aOR ?= ?1.77; 95%CI: 1.13–2.76), healthcare workers in inpatient department (aOR ?= ?2.77; 95%CI: 1.95–3.94) and injection outpatient department (aOR ?= ?2.69; 95%CI: 1.59–4.47) had significantly better odds of having appropriate BMW disposal practices.ConclusionOur study shows that nearly during three-fourth of the observations, healthcare workers performed appropriate BMW disposal practices. However, measures should be taken to achieve 100% compliance by healthcare workers especially the target groups identified in our study by allocating appropriate resources and periodically monitor the BMW disposal practices.     

Awareness and practices regarding bio-medical waste management among health care workers in a tertiary care hospital in Delhi

Health care institutions are generating large amount of Bio-Medical Waste (BMW), which needs to be properly segregated and treated. With this concern, a questionnaire based cross-sectional study was done to determine the current status of awareness and practices regarding BMW Management (BMWM) and areas of deficit amongst the HCWs in a tertiary care teaching hospital in New Delhi, India. The correct responses were graded as satisfactory (more than 80%), intermediate (50–80%) and unsatisfactory (less than 50%). Some major areas of deficit found were about knowledge regarding number of BMW categories (17%), mercury waste disposal (37.56%) and definition of BMW (47%).     

Mercury hygiene and biomedical waste management practices among dental health-care personnel in public hospitals in Lagos State,Nigeria

BackgroundIndiscriminate disposal of hospital wastes including mercury/amalgam wastes pose a serious threat to life and environment. There is a growing concern about biomedical waste (BMW) management among health care workers, however there are limited reports on BMW management by dental personnel in developing countries.ObjectivesThis study investigated the level of knowledge of BMW, observance of proper mercury hygiene and BMW management practice among public dental personnel in Lagos State, Nigeria.MethodsA cross-sectional study regarding BMW management across public hospitals in Lagos State, Nigeria was conducted following institutional ethics committee approval. A self-administered questionnaire was utilized to obtain data from different facilities selected by purposive and simple random sampling techniques as applicable. The questionnaires were distributed among 437 respondents by convenience sampling. The resulting data were statistically tested using Chi-square and G-test with p-value < 0.05 indicating significant level.ResultsAmongst 437 respondents, majority were females (62.5%) and the highest proportion fell within the age range of 25–34 years (44.4%). Only 17.2% of the respondents had good knowledge of BMW management/legislation and 4.1% had good BMW practice. Less than half (49.4%) of respondents disposed mercury-contaminated materials inside the trash and majority (92.2%) did not observe proper mercury hygiene. Significantly better mercury hygiene practices were observed in secondary facilities (p=0.040).ConclusionA minor proportion of public dental personnel had good knowledge and practice of proper mercury hygiene and BMW management. This shows there is an urgent need for training of health personnel on proper BMW handling and disposal in developing countries like Nigeria.     

Surgical hand scrub: lots of water wasted

BACKGROUND: Surgical hand scrub (SHS) is an important antisepsis measure before participating in surgical operation. It reduces the risk of microbial contamination of the surgical wound by skin flora. SHS is usually performed in a scrub sink with taps that have hand operated handles. During the scrub process large volume of water is wasted. The aim of this study was to determine the volume of water used during SHS in comparison to the actual volume necessary. METHOD: Unknown to them various cadre of the operation team were timed during their first scrubbing of the day for scheduled operations. Duration of scrubbing (ST) and that during which the hands were being washed with flowing water (WT) were recorded. The amount of water flowing through the tap per minute was also recorded. Using the mean ST, WT and water flow per minute the total volume of water used during scrubbing and that necessary to wash the hand were calculated. RESULTS: Overall, the ST ranged between 3 and 7 minutes with a mean of 4.8 +/- 0.5 SD minutes. Mean WT was 1.4 +/- 0.4 SD minutes. The mean water flow was 4,217mls per minutes. The volume of water used per scrubbing was 20.2 litres while only 5.9 litres was used for washing the hands. Between January and December 2002, the volume of water used for scrubbing was 200,283 litres while only 58,498.5 litres (29.2%) was necessary. CONCLUSION: Plenty water is wasted during STIS. Reducing the amount of water flowing unused would provide cost saving to the hospital. The use of taps operated with foot pedal would reduce the waste.     

Hypochlorite (1%) is inefficient in decontaminating blood containing hypodermic needles

Infectious biomedical waste and sharps have a potential hazard of transmission of pathogens. Among sharps, used needles form a major share and disinfection by 1 % hypochlorite is recommended in biomedical waste management rules of India. The aim of the present study was to evaluate the efficacy of hypochlorite for the decontamination of needles. Needles (16 g) filled with suspensions of standard strains and clinical isolates of gram positive and gram negative bacteria in plain normal saline and in human blood containing anticoagulant, were exposed to 1% hypochlorite and the surviving bacteria were subjected to viable counts. The observations indicated that 85 - 90 % of the needles filled with bacterial suspensions in saline are disinfected to a level of > 5 log bacterial reduction (standard disinfection) on exposure to hypochlorite but only 15 to 30% needles contaminated with the challenge bacteria suspended in blood showed > 5 log reduction in viable counts. Thus, hypochlorite treatment is inadequate for disinfecting needles contaminated with pathogenic bacteria in presence of blood and should not be recommended as an option for disinfection of the needles.     

Biomedical Waste Management Guidelines 2016: What’s done and what needs to be done

The latest biomedical waste (BMW) management guidelines which have been introduced in 2016 are simplified and made easier so that they can be easily followed by various health agencies. The categories of BMW have been reduced from ten (in 1998) to four in the latest (2016) guidelines. Many changes have been made in these latest guidelines, which have been summarised in the article below. The segregation of hospital waste plays a very important role, so the waste has to be sorted out at the source of generation according to the category to which it belongs as given in the newer guidelines. Newer waste treatment facilities such as plasma pyrolysis, encapsulation, inertisation have been introduced, and we have to do away with older facilities such as incineration as toxic fumes (dioxins and furans) are produced which are harmful to both health and environment. We can even think of using these wastewater treatment plants to remove the antimicrobial resistance genes during the processing of the waste, which is being generated from the hospitals.     

Treatment of discarded blood units: disinfection with hypochlorite / formalin versus steam sterilization

Blood bank regulations and bio medical waste rules of India advocate disinfection of contaminated blood units. Incineration is not recommended due to poly-vinyl chloride (PVC) content of blood bags. This study was designed to evaluate the efficacy of chemical disinfection of blood units deliberately contaminated with Staphylococcus aureus and E. coli with 1 and 6 % hypochlorite, 10% formalin and 33% formaldehyde and autoclaving of blood units contaminated with the above mentioned vegetative forms and B. stearothermophilus spores. Only 33 % formaldehyde could bring about 5 log reduction of bacteria but it is highly irritating and toxic. Autoclaving at 15 lbs pressure for 2 hours uniformly inactivated the vegetative forms and B. stearothermophilus spores. Thus, autoclaving of PVC blood bags is a safer and reliable method compared to chemical disinfection.     

Internal audit in a microbiology laboratory.

AIM--To set up a programme of internal laboratory audit in a medical microbiology laboratory. METHODS--A model of laboratory based process audit is described. Laboratory activities were examined in turn by specimen type. Standards were set using laboratory standard operating procedures; practice was observed using a purpose designed questionnaire and the data were analysed by computer; performance was assessed at laboratory audit meetings; and the audit circle was closed by re-auditing topics after an interval. RESULTS--Improvements in performance scores (objective measures) and in staff morale (subjective impression) were observed. CONCLUSIONS--This model of process audit could be applied, with amendments to take local practice into account, in any microbiology laboratory.     

Practice of universal precautions among healthcare workers

INTRODUCTION: Healthcare workers (HCWs) are exposed to bloodborne infections by pathogens, such as HIV, and hepatitis B and C viruses, as they perform their clinical activities in the hospital. Compliance with universal precautions has been shown to reduce the risk of exposure to blood and body fluids. This study was aimed at assessing the observance of universal precautions by HCWs in Abeokuta, Ogun State, Nigeria. SUBJECTS AND METHODS: The study was conducted in September 2003 in Abeokuta metropolis, Ogun State, Nigeria. The respondents were doctors, trained and auxiliary nurses, laboratory scientists and domestic staff. They were selected through a multistage sampling technique from public and private healthcare facilities within the metropolis. The instrument was an interviewer-administered, semistructured questionnaire that assessed the practice of recapping and disposal of used needles, use of barrier equipment, handwashing and screening of transfused blood. RESULTS: There were 433 respondents, 211 (48.7%) of which were trained nurses. About a third of all respondents always recapped used needles. Compliance with nonrecapping of used needles was highest among trained nurses and worst with doctors. Less than two-thirds of respondents (63.8%) always used personal protective equipment, and more than half of all respondents (56.5%) had never worn goggles during deliveries and at surgeries. The provision of sharps containers and screening of transfused blood by the institutions studied was uniformly high. A high percentage (94.6%) of HCWs observed handwashing after handling patients. The use of barrier equipment was variable in the institutions studied. CONCLUSION: Recapping of used needles is prevalent in the health facilities studied. Noncompliance with universal precautions place Nigerian HCWs at significant health risks. Training programs and other relevant measures should be put in place to promote the appropriate use of protective barrier equipment by HCWs at all times.     

某三级综合医院医务人员血源性职业暴露调查分析

目的 分析医务人员血源性职业暴露的危险因素,为制定职业暴露预防控制措施提供可靠依据。方法 通过现场调查和资料分析我院2017年1月~2018年12月188名医务人员职业暴露情况,分析其工龄、职业、科室分布、暴露方式及操作环节、暴露源种类及暴露后处理情况。结果 共188例血源性职业暴露医务人员,高危人群以护士为主、占67.02%;工作年限以＜5年的医护人员为主,占45.21%;科室以外科工作的医护人员为主,占47.34%。职业暴露方式以锐器伤为主,占89.89%,其次为黏膜暴露和破损皮肤。职业暴露操作环节以锐器处理不当为主,占45.21%;其次为输液拔针、医疗废物再次分类、其他、器械清洗、缝合、传递手术锐器。暴露源中以HBV感染为主,占29.79%;其次为不明暴露源、梅毒、病原均为阴性、丙肝、HIV。结论 某三级综合医院医务人员血源性职业暴露以护士、工作年限＜5年、外科工作者为主,职业暴露方式以锐器伤为主,职业暴露操作环节以锐器处理不当为主,暴露源以HBV感染为主。因此,医院应加强重点人群、重点环节的职业安全教育,合理配置防护用品,建立健全职业暴露防控机制,有效降低职业暴露发生率。     

Occupational sharps injuries in a Dublin teaching hospital

Contaminated sharps injuries pose a risk of infection to health care workers and represent a major workload for hospital occupational health departments (OHDs). The aim of this study was to review the epidemiology and management of sharps injuries in an Irish tertiary referral centre, which has not been previously described. Occupational health records of sharps injuries occurring between January 1998 and December 2000 inclusive were reviewed from the hospital OHD. A total of 332 sharps injuries were reported to the OHD in this period. More than two-thirds of injuries involved medical or nursing staff. Support staff such as cleaners and porters accounted for 13.5% of injuries. The majority of sharps injury recipients (86%) were immune to hepatitis B. Of those injured, 22% were not wearing gloves at the time of their injury. Eight source patients were hepatitis C antibody positive, two were HIV antibody positive and one was hepatitis B surface antigen positive. No instances of occupational acquisition of blood borne viruses were documented. The results of this study confirm that health care workers need further education to prevent sharps injuries, and that the risk of blood borne virus acquisition through an occupational sharps injury is low but not negligible.     

颊脂垫的解剖及其在面颊部整形美容外科中的应用

目的探讨颊脂垫的解剖结构及其临床应用。方法对13个经福尔马林固定尸体头颅标本进行解剖,详细观察其位置、大小、形态、血液供应及其与周围组织关系。临床上对43例面颊部饱满者行口内径路颊脂垫部分切除术。结果颊脂垫是面颊部深层组织间隙中的脂肪组织,由1个体部和4个突起组成,外被包膜,有丰富且多源性血液供应,与腮腺管、面神经和三叉神经的分支等关系密切,颊突和体部占总重量的55%～70%,为手术切除的主要部分。43例患者术后面部外形均令人满意,取得较好的美容效果。结论颊脂垫的部分切除有利于椭圆脸的塑造。     

A simplified method for purification, concentration and freezing of bone marrow cells for autologous transplantation

Autologous bone marrow (BM) transplantation is being increasingly applied in hematological and oncological patients. However, because of the need to purify and preserve BM requiring high technology, such treatments are virtually concentrated in the "developed" countries. This paper examines methods of BM purification and freezing that could make the technique potentially applicable in developing countries. Hemapheresis is routinely applied for BM purification in our Dutch Centre, where the buffy coats obtained from routine blood donations were utilised in experimental settings. Using DMSO as cryoprotectant, semi-purified white cells were frozen in liquid N2 (LN2), by mechanical freezer or snap-frozen at -55 degrees C. Different types of containers were compared including plastic tubes and ordinary blood bags. After thawing the results show that snap-freezing had a deleterious effect but the cell yields and viability were similar in LN2 or the mechanical freezer where the tubes and the bag were equally effective as containers (86% cell recovery with 90% viability). In the purification/concentration stage, reduction of the volume of the material by extra centrifugation, thus requiring less DMSO, produced better results--96% cell yield and 90% viability after thawing. This simplified method was applied in a general hospital in Sao Paulo where four oncology patients underwent BM collection. BM was purified and concentrated within a blood bank facility. Hydroxyethyl starch sedimentation and centrifugation of the material in plastic blood bags gave 80% BM cell harvest. After thawing from the mechanical freezer 1 x 10(8) BM cells/kg were available for reinfusion to patients. There was no immediate untoward reaction. Three of the patients showed signs of bone marrow regeneration by three weeks, but one patient died 16 days after transplantation, of septicemia. We conclude that certain high-technology procedures for ABMT can be adapted for existing facilities in developing countries.     

Fel d 1 production in the cat skin varies according to anatomical sites

BACKGROUND: Fel d 1 is the major cat allergen, inducing asthma in sensitized individuals. It is produced by the skin and lies on fur. Recently, it was established that the amount of Fel d 1 on fur varies among anatomical sites. However, it is not known whether the allergen production by skin varies in parallel. The objective was to compare the Fel d 1 production by male cat skin in two anatomical sites, the face and the chest, in order to correlate it with Fel d 1 amounts on fur, and to assess the reaccumulation of Fel d 1 after washing. METHODS: Ten intact male cats were shaved under general anesthesia at both areas, and the fur was collected. The skin was washed and the washing fluid collected for Fel d 1 assays. Fel d 1 levels were measured in microg/g fur and ng/cm2 skin by ELISA before and after washing and 48 h later. RESULTS: In skin washing, the mean Fel d 1 level was significantly higher in the face (1015.2 +/- 821.6 ng/cm2) than the chest (115.2 +/- 66.8 ng/cm2). In the fur, the respective levels were 63.6 +/- 34 and 29.6 +/- 13.6 microg/g. In the skin sample taken after skin washing, the level of Fel d 1 dropped to 25.1 +/- 25.7 ng/cm2 on the face and to 22 +/- 17.4 ng/cm2 on the chest. After 2 days, skin Fel d 1 levels returned to basal values, with higher values on the face than the chest. CONCLUSIONS: This study shows that Fel d 1 levels on the skin are dramatically higher on the facial area than chest. This anatomical variation is concordant with the levels of Fel d 1 found on fur. Washing reduces levels of major allergen on cat skin and fur, but the accumulation on skin is restored within 2 days.     

Same-day identification and antibiotic susceptibility testing on positive blood cultures: a simple and inexpensive procedure

Fast diagnostic tools are becoming a hot topic in microbiology, especially in the case of septic patients. Therefore, we attempted to develop a fast, inexpensive, accurate and easy method to identify bacteria and perform an antibiotic susceptibility test directly on positive blood cultures that could be used in a routine laboratory. A procedure based on centrifugation and washing steps was performed on 110 non-duplicated (including nine seeded) positive blood culture bottles. Direct identification (DID) and antimicrobial susceptibility testing (AST) was conducted on the pellet with the MALDI Biotyper and Phoenix, respectively. Identification (ID) to the species level was correct in 44/45 (97%) cases for Gram-negative bacteria and 44/56 (79%) cases for Gram-positive bacteria. In total, 98.9% of the AST results were identical to the routine laboratory result. No very major errors, four major errors and eight minor errors were detected. A reliable identification and a high AST agreement were obtained from blood cultures seeded with multi-resistant bacteria. We simulated the timeline of DID and demonstrated an identification and AST result within 24 h using Escherichia coli- and Staphylococcus aureus-positive blood cultures as examples. We developed an easy, fast and cheap method to generate reliable ID and AST results. Moreover, this method may be used to obtain results within 24 h after incubating the blood culture bottles in the microbiology lab.     

Precautions in medical care of, and in handling materials from, patients with transmissible virus dementia (Creutzfeldt-Jakob disease).

We have formulated a series of precautions to be observed in caring for patients with Creutzfeldt-Jakob disease and in handling their tissues. The virus resists inactivation by simple boiling in water. Also ineffective are 10 per cent formalin, 70 per cent alcohol and ionizing and ultraviolet radiation. Autoclaving for one hour at 121 degrees C and 20 psi inactivates the agent completely. Five per cent hypochlorite, 0.03 per cent permanganate, phenolics and iodine solutions are adequate disinfectants inactivating large infective doses of the virus. Special isolation wards for afflicted patients seem unwarranted. Workers exposed to infected saliva, nasopharyngeal secretions, urine or feces need to and should wash thoroughly with ordinary soap. Needles and needle electrodes should be autoclaved or incinerated and discarded. Demented persons should not be used for donations of blood or other tissues. Although precautions are necessary, the epidemiologic evidence does not suggest an unusual risk of Creutzfeldt-Jakob disease for medical workers.     

Dispositif pneumatique pour le transport des produits sanguins labiles

Blood product transport from blood bank to the patient care areas of hospitals is a key step in the transfusion process. The pneumatic tube system is now widely used in hospitals. Strict performance specifications must be respected to guarantee blood safety: robustness, easy to use and respect the constraints imposed to blood products. To secure the disposal of blood products ordered to a carrier (delivery step), a security device must be deployed (video camera, barcode reading, fax, chip), allowing in particular to limit the risk of addressing error when sending (in the case of device with several arrival stations) or picked up by the wrong carrier.     

The release of contaminants from steel slags and natural aggregates: Evaluation of toxicity and genotoxicity

Steel slags (SS) are the major waste produced by iron and steel industry. Slags may be reused as recycled materials, instead of natural aggregates (NA), to reduce the final disposal in a landfill and the exploitation of raw materials. However, the reuse of SS may generate a potential release of toxic compounds for the environment and humans. The purpose of this study was to evaluate the toxicity and genotoxicity of SS, in comparison with NA, by using an integrated chemical‐biological approach to enable their safe reuse in engineering applications. Leaching solutions from samples were obtained by using short‐term leaching tests (CEN EN 12457‐2, 2004) usually adopted for the evaluation of waste recovery and final disposal. Chemical analyses of leachates were performed according to the Italian legislation on waste recovery (Ministerial Decree 186/2006). The leaching solutions were assayed by using toxicity test on Daphnia magna. Moreover, mutagenicity/genotoxicity tests on Salmonella typhimurium, Allium cepa, and human leucocytes and fibroblasts were carried out. The releases of pollutants from all samples were within the limits of the Italian legislation for waste recovery. Despite the effects that SS and NA could have on different cells, in terms of toxicity and genotoxicity, globally, SS do not seem to be any more hazardous than NA. This ecotoxicological assessment, never studied before, is important for promoting further studies that may support the decision‐making process regarding the use of such types of materials.