Biological safety cabinetry

Most of the antineoplastic drugs used in the treatment of tumors are carcinogenic to humans. Hospital nurses are often subject to possible occupational carcinogen exposure. Exposure may occur during handling and administration of infusion solutions containing cytostatics. A genotoxicological monitoring system to detect genotoxic changes was developed in our laboratory, helping to improve working conditions and subserving primary prevention. Multiple-endpoint follow-up genotoxicological monitoring was performed in peripheral blood lymphocytes (PBLs) among 4 groups of 95 nurses (152 investigations) occupationally exposed to cytostatics. The results were compared to those of historical and industrial controls. The genotoxicological endpoints were the determination of the frequency of sister chromatid exchanges (SCEs) and the cells with high-frequency SCEs (HFC), the frequency of structural and numerical chromosome aberrations, and the measurement of ultraviolet-light-induced unscheduled DNA-repair synthesis (UDS). In Hospital 1, where nurses worked without a safety cabinet, the percentage of cells with chromosome aberrations (AC) was significantly higher than that of the controls. In Hospital 2, where nurses used inadequate safety cabinets (with horizontal airflow), significantly elevated levels of AC, SCE, HFC, and UDS were detected. During follow-up, in Hospital 2 at the time of the second investigation AC was still significantly higher, although safety conditions had been improved. The results indicate the presence of genotoxic damage in hospital nurses working with no or inadequate safety equipment. In Hospitals 3 and 4 where nurses using biological safety cabinets, the results were lower than those in the previous two groups. In Hospital 3 in the first year of the study AC was as at the level of industrial controls. During follow-up in the course of the repeated investigations a fluctuation in AC above the control level and an increase in HFC in yr 4 and 6 of the study were observed. In this group, the fluctuation in AC and HFC during the study points to the possibility of genotoxic exposure with cytostatics despite of the use of suitable safety cabinets, drawing attention to other possible routes of exposure. In Hospital 4, both AC and HFC were elevated. These data corroborate the need to maintain safety measures to avoid exposure, and the necessity of intervention in the case of exposure when using and handling hazardous carcinogenic agents. The results also indicate a certain expression time for genotoxic changes, which can lead to late somatic mutations as well as to a possible higher risk of cancer.

Background: Technical protection measures for laboratory activities involving biological agents include biological safety cabinets (BSC) that may be contaminated. In the case of diagnostic activities with SARS-CoV-2, this may also affect BSC that are operated at protection level 2; therefore, decontamination of all contaminated surfaces of the BSC may be required. In addition to fumigation with hydrogen peroxide (H2O2), dry fogging of H2O2-stabilized peroxyacetic acid (PAA) represents another alternative to fumigation with formalin. However, to prove their efficacy, these alternatives need to be validated for each model of BSC.Methods: The validation study was performed on 4 different BSCs of Class II A2 using the “Mini Dry Fog” system.Results: An aerosol concentration of 0.03% PAA and 0.15% H2O2 during a 30 min exposure was sufficient to inactivate SARS-CoV-2. Effective concentrations of 1.0% PAA and 5% H2O2 were required to decontaminate the custom-prepared biological indicators loaded with spores of G. stearothermophilus and deployed at 9 different positions in the BSC. Commercial spore carriers were easier to inactivate by a factor of 4, which corresponded to a reduction of 106 in all localizations.Conclusions: Dry fogging with PAA is an inexpensive, robust, and highly effective decontamination method for BSCs for enveloped viruses such as SARS-CoV-2. The good material compatibility, lack of a requirement for neutralization, low pH – which increases the range of efficacy compared to H2O2 fumigation – the significantly shorter processing time, and the lower costs argue in favor of this method.

In Japan, biological safety cabinets are commonly used by medical staff to prepare antineoplastic agents. At the Division of Chemotherapy for Outpatients, Nagoya University Hospital, a class II B2 biological safety cabinet is used. The temperature inside this biological safety cabinet decreases in winter. In this study, we investigated the effect of low outside air temperature on the biological safety cabinet temperature, time required to admix antineoplastic agents, and accuracy of epirubicin weight measurement. Studies were conducted from 1 January to 31 March 2008 (winter). The outside air temperature near the biological safety cabinet intake nozzle was compared with the biological safety cabinet temperature. The correlation between the outside air temperature and the biological safety cabinet temperature, time for cyclophosphamide and gemcitabine solubilization, and accuracy of epirubicin weight measurement were investigated at low and high biological safety cabinet temperatures. The biological safety cabinet temperature correlated with the outside air temperature of 5-20℃ (p < 0.0001). Compared to cyclophosphamide and gemcitabine solubilization in the biological safety cabinet at 25℃, solubilization at 10℃ was significantly delayed (p < 0.01 and p < 0.0001, respectively). Measurement of epirubicin weight by using a syringe lacked accuracy because of epirubicin's high viscosity at low temperatures (p < 0.01). These results suggest that the biological safety cabinet temperature decreases when cool winter air is drawn into the biological safety cabinet, affecting the solubilization of antineoplastic agents. We suggest that a decrease in biological safety cabinet temperature may increase the time required to admix antineoplastic agents, thereby increasing the time for which outpatients must wait for chemotherapy.

ABSTRACTBackgroundStudies from Europe, the US and Australia have shown measurable levels of cytotoxic contamination in health facilities. Cytotoxic drug residue has been detected in the air and on surfaces in preparation areas even though work was undertaken in biological safety cabinets. Several studies have found substantial levels of surface contamination in pharmacy drug preparation and administration areas. At the time this study was conducted there were no published Australian studies investigating surface contamination when cytotoxic drug safety cabinets are in use.AimTo determine if surface contamination with cytotoxic drugs occurs when cytotoxic drug safety cabinets are used by pharmacy personnel to prepare cytotoxic chemotherapy.MethodA multicentre study conducted at 10 hospital pharmacy departments in metropolitan Melbourne. All sites were tested to measure the amount of cytotoxic contamination present using cyclophosphamide as a surrogate marker for all cytotoxic drugs. Surface wipe sampling was performed at specified locations within the cytotoxic suites.ResultsCyclophosphamide contamination was detected in 78% of samples taken within the cytotoxic drug safety cabinet, with 100% contamination detected in the sump. Positive results were also found in 89% of floor samples (cleanroom and anteroom) and 67% of checking benches.ConclusionCytotoxic drug contamination was detected on a variety of surfaces in the cytotoxic drug preparation areas that used cytotoxic drug safety cabinets. The potential risk of exposure to cytotoxic drugs exists in the workplace despite adherence to the recommended safe handling guidelines.

Preventing Infectious Aerosol Hazards to Laboratorians: A Team Effort To Obtain Biological Safety Cabinets for Oregon Sentinel Hospital Labs

Objective: Biological Safety Cabinets are the primary containment device used to protect the worker, environment and product from exposure to infectious agents within the laboratory. Spores of Bacillus subtilis are used as tracer agents to test Class II biological safety cabinets in NSF/ANSI Standard 49 and others. However, none of these standards characterizes the viral challenge tests. Methods: One model bacterium and two different phages were selected to challenge two new Class II biological safety cabinets strictly conforming to the NSF/ANSI Standard 49 requirements. Results: The two tested biological safety cabinets met the requirements of personnel, product, and crosscontamination protection test no matter which agent was used to challenge the system. However, the high efficiency particulate air filter leak testing results indicated that viral aerosol might penetrate through filter while bacterial could not. Conclusions: The penetration ability of viral aerosol through HEPA filter might be superior to bacterial. This viral testing method might be a potential way used for the exhaust HEPA filter leak certification due to being able to reflect the containment performance of biological safety cabinet truly and intuitionally.

Class II biological safety cabinets, normally used for low to moderate risk agents, are being recognized as providing a capability in certain laboratory and industrial situations whereby materials which are potentially hazardous to human health and/or to the environment may be controlled during routine processing thus providing personnel, product and environmental protection. As interest in these safety devices increases, so does the importance of understanding: what types of cabinets are available, how they are designed to function, their proper use, and how they may be expected to perform. A Class II Type A biological safety cabinet was challenged with Bacillus subtilis var. niger spores at line voltages from 85 to 130 volts in order to determine its performance during simulated brownout and power surge conditions. The cabinet, employing a 20.3 cm (8 in.) work opening passed both personnel and product protection tests at all voltages used. The cabinet, fitted with the 25.4 cm (10 in.) work opening passed the same tests with the exception of the personnel protection test at 85 volts. It was concluded that, when the stated motor-blower performance characteristics are provided, this cabinet design will perform its safety function over a considerable range of line voltages.

In Japan, biological safety cabinets (BSCs) are normally used by medical staff while handling antineoplastic agents. We have also set up a class II B2 BSC at the Division of Chemotherapy for Outpatients. The air temperature inside this BSC, however, decreases in winter. We assumed that this decrease is caused by the intake of open-air. Therefore, we investigated the effects of low open-air temperature on the BSC temperature and the time of admixtures of antineoplastic agents. The studies were conducted from January 1 to March 31, 2008. The outdoor air temperature was measured in the shade near the intake nozzle of the BSC and was compared with the BSC temperature. The correlation between the outdoor air temperature and the BSC temperature, the dissolution time of cyclophosphamide (CPA) and gemcitabine (GEM), and accurate weight measurement of epirubicin (EPI) solution were investigated for low and normal BSC temperatures. The BSC temperature was correlated with the open-air temperature for open-air temperatures of 5-20°C (p < 0.0001). The dissolution of CPA and GEM at these temperatures was significantly delayed as compared to that at 25°C (p < 0.01 and p < 0.0001, respectively). The weight measurement of EPI solution using a syringe method lacks accuracy because of its high coefficient of viscosity at low temperatures (p < 0.01). These results suggest that the BSC temperature decreases below room temperature in winter when air is drawn from outdoors. We showed that the BSC temperature affects the dissolution rate of antineoplastic agents. Further, we suggested that the BSC temperature drop might delay the affair of the admixtures of antineoplastic agents and increase the waiting time of outpatients for chemotherapy.

Many healthcare workers are concerned about the risk of occupational exposures to hazardous drugs. The Japanese Society of Hospital Pharmacists (JSHP) revised the "Guidelines for the Handling of Antineoplastic Drugs in Hospitals", however, the precautions and awareness of handling drugs varied in institutions. We assessed the levels of environmental contaminations in our hospital and urinary excretion of cyclophosphamide (CP) and ifosfamide (IF) in pharmacists and nurses. In environmental studies, we obtained samples by wiping the surfaces around two biological safety cabinets (BSCs) on eight days for four months. One BSC was equipped in hospital pharmacy and the other was equipped in an oncology ward, and used for preparing chemotherapeutic drugs for outpatients and for inpatients, respectively. We obtained the urine samples from 6 pharmacists and 2 nurses. We used solid phase extraction (SPE) as a convenient extraction procedure and liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) for the analysis of the samples. CP was detected on the working surfaces inside both BSCs, and detected at low levels on the back surfaces of the BSCs and at the working tables around the BSCs. IF over the LLOQ was not detected in both BSCs. CP and IF were not detected in all urine samples of pharmacists and nurses. Detection frequencies and amounts of these drugs were low levels, compared with previous reports in Japan, and our results showed that improving awareness about handling hazardous drugs could reduce the risk of the occupational exposures.

When properly used and adequately maintained, a biological safety cabinet (BSC) provides protection to the laboratory worker, the products, and the environment. Knowledge about proper use of the BSC is therefore important. This study evaluated BSC usage knowledge and practices and the effect of prior experience on training outcomes. Thirteen participants randomly selected from research centers were evaluated through a structured questionnaire covering biosafety considerations involved in using a BSC as per the World Health Organization’s Laboratory Biosafety Manual, third edition. The questionnaire was administered before and after the training. Training was conducted using the NUITM-KEMRI biosafety training program, enhanced to include more modules on BSCs. Differences in the participants’ knowledge and practices regarding BSC usage were observed. After training, the participants were able to give correct responses. Furthermore, participants who had fewer years of experience showed the greatest improvement. Results indicate the need for proper training of laboratory workers early in their careers, coupled with close supervision, mentorship, and regular refresher training.

Biological safety cabinets (BSCs) are the primary means of containment used in laboratories worldwide. To ensure the proper functioning of BSCs, they need to be certified annually, at a minimum, per National Sanitation Foundation (NSF)/American National Standards Institute Standard 49. A common problem most organizations face is that in many instances, the technicians who certify the cabinets are not accredited by the NSF. Additionally, in states or regions that do not have local NSF accredited field certifiers, it takes weeks to get a service request completed, thereby delaying the research work of the laboratory. Moreover, in such instances, the cost associated with cabinet certification and repair can be very high. This led the Office of Safety at the University of North Dakota to do a thorough cost-benefit analysis of developing an in-house BSC certification program. After completing the training and testing requirements for the NSF's advanced accreditation program, the BSC certification program was initiated on campus. The identified benefits led to the initiation of a program in both local and regional capacity for repair, maintenance, and certification of BSCs, and the university's experiences were shared with other universities. By developing an in-house BSC certification program, the University of North Dakota was able to reduce wait times associated with service repairs, reduce costs, and generate revenue for the department. Furthermore, this led to improved hands-on training programs related to BSC use in laboratories working with biohazardous agents.

Class II Biological Safety Cabinets (BSCs) are widely used in biological and chemical research for protection of the investigator, the environment, and the project. However, researchers' operational procedures are often inconsistent with BSC design limitations. While the Class II BSC is only a partial containment cabinet, better design and user training can improve containment, thereby increasing personnel protection. The authors developed design modifications for a Class II BSC to permit internal waste collection and to optimize the available work area. An internal recessed well for the waste receptacle, relocation of petcocks and electrical duplex, and installation of a new vacuum bottle make operation of the cabinet more efficient and potentially safer. To correct poor work practices, which can compromise the protective features of any BSC, precise guidelines and training programs should be relied on. Standardization of guidelines for operation of BSCs would be beneficial to the clinical and research community, given the frequent exchange of investigators among biomedical institutions.

Biological Safety Cabinet (BSC) is a laboratory work area with air ventilation that has been engineered to protect workers working with material samples, the environment and material samples from the possible danger of contamination or causing the spread of pathogenic bacteria or viruses. The purpose of this study is to analyze the stability of the time required for the BSC to reach the condition of no particles in the BSC space. This is done by making a module using the PMS7003 sensor to detect the number of particles. This study uses the Arduino Mega system for data processing and then displays it in the form of graphs and numbers. In the condition of the number of particles of 162,965, the time required for the BSC is 29 seconds, while in the condition of the number of particles of 186,408, the time required is 38 seconds. So it is known that if the number of particles in the BSC space is more and more particles in the BSC space, the longer it takes for the BSC to reach the no-particle condition. BSC that uses a single fan blower cannot achieve a stable number of particles simultaneously.

Introduction:The operator protection factor (OPF) of four biological safety cabinets (BSCs) has been measured under standard and suboptimal conditions.Methods:The OPF for one BSC1, two BSC2, and an acid-fast bacilli staining station (AFBSS) was measured using the potassium iodide method for in situ testing of BSCs (CEN12469) over a range of inflow velocities under standard conditions and with common interfering factors (fans, opening doors, and walk pasts).Results:The BSC1 and the AFBSS gave a high level of protection under standard test conditions at all airflows (down to 0.3 and 0.38 m/s, respectively). During interfering processes, the BSC1 and AFBSS gave a high level of protection (OPF >105) at the specified inward airflow. At lower airflows, there was a predictable deterioration in performance. There was a significant difference in performance between the two BSC2s tested, with one model passing all tests under all interfering conditions at all airflows. The second BSC2 failed the standard test at the lowest airflow and provided poor levels of protection (OPF <105) in all tests carried out with interfering processes.Conclusion:Although BSC2s are capable of giving a high level of performance, this is design dependent and the BSC1 and AFBSS give a more predictable level of performance due to their simpler design. In environments where BSC certification is not possible, they may provide more robust and sustainable primary containment.

Ultraviolet radiation is often used to decontaminate the interior surfaces of biological safety cabinets (BSCs). The Centers for Disease Control and Prevention (CDC) recommends a UV lamp intensity of 40 μW/cm2 at the center of the work area to ensure surface decontamination. A commonly-used source of UVC in BSCs—the G30T8 lamp—provides approximately 125 μW/cm2 one meter from the lamp. However, since many BSCs have an interior height of less than one meter, UV intensities at the work surface should be considerably higher because UV radiation follows an inverse square law. Few laboratories have the instruments necessary to measure UVC intensity. The Web site of the Atlantic Ultraviolet Corporation lists UV dosages required to kill a wide range of micro-organisms. This study investigates the possibility of using readily available strains of 4 common bacteria to monitor the output of UV lamps in BSCs. Inoculated plates with 4 bacterial strains were exposed to UV radiation in a plate carrier device exposed for different times and in different locations in the BSC. Half the plates were covered with a strip of aluminum to serve as an unexposed growth control. Reduced UV intensities were simulated using Petri dish sleeves that provided a range of UV intensities from 20 μW/cm2 to 510 μW/cm2. Various UV intensities were measured in different areas of the BSC, and compared with calculated and estimated values. Various times to kill the bacteria were measured based on bacterial strain, UV intensity, exposure time, and location in the BSC. In a blinded study in which the UV intensities were estimated from the killing times of the bacteria and compared with actual measured values, 4 of the 6 measured values were in the estimated ranges, and 2 estimated ranges were slightly below the measured values. Our results support the hypothesis that cultures of known bacterial strains could be used to closely estimate the UV lamp output.