Environmental monitoring programme in the cell therapy facility of a research centre: preliminary investigation.

INTRODUCTION: Recent discoveries in cell therapy research present new opportunities for cellular products to be used to treat severe, and as yet incurable, diseases. It is therefore essential to implement a quality control programme in order to ensure that safe cells and tissues are provided. METHODS: In a preliminary phase of the setting up of a the cellfactory, monitoring was carried out monthly over a 6-month period in one out of three cell therapy laboratories and filter rooms in order to evaluate the microbial contamination of air and surfaces and the presence of airborne particulates. RESULTS: The mean total bacterial and fungal loads measured in the air in the centre of the filter room were 20.7 +/1 28.9 colony-forming units (cfu)/m3 and 9.2 +/- 15.4 cfu/m3, respectively, and 5.2 +/- 4.1 cfu/m3 and 6.8 +/- 13.4 cfu/m3, respectively, in the laboratory. The mean fungal load values recorded on the surfaces sampled in the laboratory were in 6 out of 18 cases higher than the reference values (5 cfu/plate). As to the results of particulate monitoring, with regard to the 0.5 microm particles, about 83% of the samples revealed values below the limit of 350.000 particles per cubic metre. CONCLUSIONS: In this set-up phase, monitoring was able to pick out structural and organisational flaws acceptable in a laboratory compliant with Good Manufacturing Practices class C (Annex 1), but not in a class B facility. Thanks to this preliminary monitoring phase, and by correcting these flaws, the clean room facility could achieve compliance to class B.

Investigation of organizational and hygiene features in dentistry: a pilot study.

INTRODUCTION: In dentistry, as in surgery, there is a risk of cross-infection for both patients and staff The aim of this research was to evaluate procedures and behaviors enacted by dental staff which might engender a risk for themselves and their patients. METHODS: A questionnaire was administered to 106 dental workers in Genoa (Italy), both public and private. Whenever personal interviews were conducted, the facilities involved were also inspected and the activities of the dental staff were observed directly. RESULTS: This research highlighted some critical points in both structural and organizational features and in the management of infective hazards in the sample considered. In some cases, inadequacies were noted with regard to the prevention of cross-infections, such as the lack of disinfection of work surfaces and the handles of chair-set accessories. DISCUSSION AND CONCLUSIONS: The particular nature of dental work, in which aerosols of blood and saliva may be produced by rotating instruments, engenders a risk of infection. Application of the various preventive measures available can significantly reduce microbial contamination and the risk of occupational infection and cross-infections. Furthermore, improvement in the structural and organizational features of dental surgeries and the continuing education of health-care workers is indispensable to the control and prevention of infectious diseases.

Evaluation of contamination by blood aerosols produced during various healthcare procedures.

This study aimed to quantify the blood content of aerosols produced during dental, maxillofacial and autopsy procedures and to identify those activities which involve the greatest risk of infection due to exposure to blood-containing aerosols. A total of 132 air samples were taken in several dental cubicles, a maxillofacial operating theatre and an autopsy room. The concentration of haemoglobin (Hb) in the samples was quantified and, for each day of sampling, the concentration of blood/m(3) of air aspirated (muL blood/m(3) air) was calculated. Hb was detected in 38.64% of samples. The mean concentration of Hb in the samples was 0.10+/-0.19 microg Hb/m(3) of aspirated air, with a range of 0-0.72 microg Hb/m(3). No statistically significant differences in the concentration of blood aerosol per m(3) of aspirated air were noted among the three types of activity analysed (P>0.05). Although there is, as yet, no concrete proof of the risk of infection through blood-containing aerosols, minimising the production and dispersal of aerosols and spatters is strongly recommended.

Surface disinfection: evaluation of the efficacy of a nebulization system spraying hydrogen peroxide.

INTRODUCTION: The study assessed the efficacy of a system of nebulization of a hydrogen peroxide-based solution for surface disinfection. METHODS: Different concentrations (1, 2 and 4 ml/m3) of the same disinfectant solution (active principle: hydrogen peroxide) were nebulized inside a 50 m3 experimental environment. Sampling was carried out on both horizontal and vertical surfaces, and the total bacterial load at 37 degrees C was determined by means of direct contact with Rodac plates. The disinfection efficacy of the system was evaluated by comparing the total bacterial load measured on the surfaces before and after treatment. Statistical analysis was performed by means of Stata/SE9 software. RESULTS: The percentage reduction in the mean bacterial load on horizontal surfaces as a result of treatment at concentrations of 1, 2 and 4 ml/m3 proved to be 54.9%, 70.9% and 86.9%, respectively. With regard to vertical surfaces, the percentage reduction was 100% in all experimental conditions. DISCUSSION AND CONCLUSIONS: The system tested proved to be efficacious in disinfecting surfaces inside environments of 50 m3 in volume. It could therefore be used to disinfect surfaces in hospital and community settings. In healthcare facilities, disinfection by means of nebulization systems could help to reduce the risk of spreading nosocomial infections.

Fungal contamination in hospital environments.

OBJECTIVES: To assess the degree of fungal contamination in hospital environments and to evaluate the ability of air conditioning systems to reduce such contamination. METHODS: We monitored airborne microbial concentrations in various environments in 10 hospitals equipped with air conditioning. Sampling was performed with a portable Surface Air System impactor with replicate organism detection and counting plates containing a fungus-selective medium. The total fungal concentration was determined 72-120 hours after sampling. The genera most involved in infection were identified by macroscopic and microscopic observation. RESULTS: The mean concentration of airborne fungi in the set of environments examined was 19 +/- 19 colony-forming units (cfu) per cubic meter. Analysis of the fungal concentration in the different types of environments revealed different levels of contamination: the lowest mean values (12 +/- 14 cfu/m(3)) were recorded in operating theaters, and the highest (45 +/- 37 cfu/m(3)) were recorded in kitchens. Analyses revealed statistically significant differences between median values for the various environments. The fungal genus most commonly encountered was Penicillium, which, in kitchens, displayed the highest mean airborne concentration (8 +/- 2.4 cfu/m(3)). The percentage (35%) of Aspergillus documented in the wards was higher than that in any of the other environments monitored. CONCLUSIONS: The fungal concentrations recorded in the present study are comparable to those recorded in other studies conducted in hospital environments and are considerably lower than those seen in other indoor environments that are not air conditioned. These findings demonstrate the effectiveness of air-handling systems in reducing fungal contamination.

Nitrous oxide pollution in operating theatres in relation to the type of leakage and the number of efficacious air exchanges per hour.

INTRODUCTION: As occupational exposure to anaesthetic gases is one of the main risks for operating theatre staff an environmental monitoring campaign was conducted in order to evaluate the degree of pollution by nitrous oxide (N2O) in the operating theatres of some hospital facilities in Liguria. METHODS: Any leaks (systemic and/or managerial) of anaesthetic gas and the number of efficacious air exchanges per hour supplied by air-conditioning systems were evaluated by means of an IR spectrometer, which was wired to a computer for data collection and analysis. The concentration of nitrous oxide in the centre of each operating theatre was measured by means of chemo-adsorbent cartridges analysed by gas chromatography. RESULTS: In 76.0% of the operating theatres examined a mean environmental concentration of N2O below the legal limits was recorded. The highest mean concentrations were generally associated with the presence of systemic leaks. Supplying an adequate number of efficacious air exchanges per hour enabled environmental concentrations of anaesthetic gas to be kept within acceptable levels. DISCUSSION AND CONCLUSIONS: Training personnel in the correct management of the operating theatre and of anaesthesia equipment, and ensuring the availability of an adequate air-conditioning system enable the risk of exposure to nitrous oxide to be minimised. This can be achieved through a concerted effort on the part of all involved, in accordance with the concept of ongoing improvement in healthcare services.

[Occupational exposure to formaldehyde in three pathology departments]. / Esposizione professionale a formaldeide in alcuni reparti di anatomia patologica.

Although formaldehyde has recently been classified by the IARC as "carcinogenic in humans" (class 1), it is still widely used in pathology departments for the fixing and conservation of biological tissues. Its use therefore raises the question of occupational exposure. The present paper reports the results of an environmental monitoring campaign to evaluate pollution by formaldehyde in various areas of three pathology departments. Chemi-adsorbent cartridges able to adsorb airborne formaldehyde were used to detect the substance. Quantitative determination of the formaldehyde was carried out by means of liquid chromatography (HPLC). The concentrations of airborne formaldehyde in the areas monitored were fairly modest, being below the limits of indoor concentration proposed by the OSHA. In one of the three departments, however these limits were exceeded in 40% of the samples taken in the room used for the storage of containers. As yet, in spite of the recent class 1 classification by the IARC, no provisions have been made to ban the use of formaldehyde. It is therefore essential to draw up environmental monitoring programmes in order to evaluate occupational exposure and to assess the efficacy of any preventive measures adopted.