Asbestos containing materials in schools of Rome and surrounding area (Italy).

Despite Italy banning use and production of asbestos in 1992, it continues to represent a risk to human health due to its permanence in the places where it was located. The aim of this work is to estimate how many schools in Rome (Italy) have asbestos containing materials (ACM), and to assess whether the location, condition and nature of ACM can influence the level of risk for student health. 3,672 schools were contacted and 1,451 participated to asbestos survey. 692 bulk samples were collected and analyzed by optical and electron microscope and Fourier transform infrared spectrometer. About 16% of the surveyed schools had ACM. Most of the ACM were not accessible to students (water tanks, boiler thermal insulations). Asbestos-cement materials and vinyl floor tiles were the most common non-friable materials found in schools and equipment insulation linings and Bunsen burner gauze mats were the friable ACM found in science laboratories. Measures to prevent or reduce asbestos hazards were applied where necessary. This study allowed to develop the awareness of the asbestos health hazard among headteachers and the need to manage these hazards appropriately. It represents the beginning of a larger study leading to ACM national mapping in schools.

Field comparison of two inhalable samplers used in Italy to measure the wood dust exposure.

BACKGROUND: Particle size affects the performance of personal air samplers used to measure dust exposure in the workplace. Few field studies have been conducted for comparing the performance of personal inhalable samplers. OBJECTIVE: To compare wood dust sampling with two inhalable samplers: IOM (Institute of Occupational Medicine) and Italian cone. METHODS: 136 Italian cone/IOM paired samples and 136 passive IOM samples were collected in 30 Italian woodworking industries. The valid number of sample pairs was 114. Ultra-large particles were collected by passive IOM. The sampling membranes were weighed and the size particles were measured. Mass differences in active and passive IOM samples were calculated (IOM-Δ). RESULTS: Statistical analysis of all 114 Italian cone/active IOM paired results showed a significant mass difference (P < 0.05) and no significant mass difference for sanding and cutting woodworking processes. The Italian cone/IOM-Δ paired results consistently showed no statistically significant mass differences in any woodworking processes. Both samplers performed similarly when ultra-large particles mass contribution was not considered. CONCLUSIONS: These findings confirm the presence of ultra-large particles in woodworking. The Italian cone and IOM samplers can be used interchangeably for personal wood dust exposure assessment, when the wood activities produce small-size particles.

Dissolution of glass wool, rock wool and alkaline earth silicate wool: morphological and chemical changes in fibers.

The behavior of alkaline earth silicate (AES) wool and of other biosoluble wools in saline solution simulating physiological fluids was compared with that of a traditional wool belonging to synthetic vitreous fibers. Morphological and size changes of fibers were studied by scanning electron microscopy (SEM). The elements extracted from fibers were analyzed by inductively coupled plasma atomic emission spectrometry. SEM analysis showed a larger reduction of length-weighted geometric mean fiber diameter at 4.5 pH than at 7.4 pH. At the 7.4 pH, AES wool showed a higher dissolution rate and a dissolution time less than a few days. Their dissolution was highly non-congruent with rapid leaching of calcium. Unlike rock wool, glass wool dissolved more rapidly at physiological pH than at acid pH. Dissolution of AES and biosoluble rock wool is accompanied by a noticeable change in morphology while by no change for glass wool. Biosoluble rock wool developed a leached surface with porous honeycomb structure. SEM analysis showed the dissolution for glass wool is mainly due to breakage transverse of fiber at pH 7.4. AES dissolution constant (Kdis) was the highest at pH 7.4, while at pH 4.5 only biosoluble rockwool 1 showed a higher Kdis.

Angiogenic effect induced by mineral fibres.

Due to the toxic effect of asbestos, other materials with similar chemical-physical characteristics have been introduced to substitute it. We evaluate the angiogenic effect of certain asbestos substitute fibres such as glass fibres (GFs), ceramic fibres (CFs) and wollastonite fibres (WFs) and then compare angiogenic responses to those induced by crocidolite asbestos fibres (AFs). An in vitro model using human endothelial cells in small islands within a culture matrix of fibroblasts (Angio-Kit) was used to evaluate vessel formation. The release of IL-6, sIL-R6, IL-8, VEGF-A and their soluble receptors, sVEGFR-1, sVEGFR-2, was determined in the conditioning medium of Angio-Kit system after fibre treatment. ROS formation and cell viability were evaluated in cultured endothelial cells (HUVEC). To evaluate the involvement of intracellular mechanisms, EGFR signalling, ROS formation and nuclear factor-κB (NFκB) pathway were then inhibited by incubating HUVEC cells with AG1478, NAC and PDTC respectively, and the cytokine and growth factor release was analyzed in the culture medium after 7 days of fibre incubation. Among the mineral fibres tested, WFs markedly induced blood vessel formation which was associated with release of IL-6 and IL-8, VEGF-A and their soluble receptors. ROS production was observed in HUVEC after WFs treatment which was associated with cell cytotoxicity. The EGFR-induced ERK phosphorylation and ROS-mediated NFκB activation were involved in the cytokine and angiogenic factor release. However, only the EGFR activation was able to induce angiogenesis. The WFs are potential angiogenic agents that can induce regenerative cytokine and angiogenic factor production resulting in the formation of new blood vessels.

Risk assessment of the decay of asbestos cement roofs.

OBJECTIVES: In an assessment of the risk of asbestos fibres release from asbestos cement materials, an important role is played by the assessment of the surface corrosion and by the disaggregation of asbestos cement. The aim of this work is to evaluate the differences among several methods used for the risk assessment that lead to a specific choice of abatement techniques. METHODS: The state of deterioration of 40 asbestos cement roofs was evaluated using two priority assessment algorithms elaborated in Italy, the 'pull-up test' described by the Italian Organization for Standardization and the indicators described in the Italian legislation coupled with the observation of a small sample, taken from each roof, by a stereomicroscope. RESULTS: The results obtained with the methods, proposed in this study, for the risk assessment of the decay of asbestos cement roofs show slight differences among them, only one deviates from the others in judgement on the state of conservation of the roof. CONCLUSIONS: It is very important to train the operator conducting the study since a completely subjectivity-free method does not exist. Whatever method is used will always be affected by the subjectivity linked to the competency and the training of the operator. Moreover, each method on its own cannot assess the risk of exposure to asbestos, but reliable assessment of asbestos-containing materials requires the use of more than one method, such as visual inspections, a pull-up test, and an assessment algorithm.

Airborne asbestos levels in school buildings in Italy.

This article provides a summary of environmental investigations carried out from 1992 to 2002 by the National Institute for Occupational Prevention and Safety on airborne asbestos fiber concentrations in Italian schools. The monitoring was performed to evaluate the risk from asbestos exposure to students and school staff. Fifty-nine schools located in several Italian regions were studied. A detailed visual examination assisted with locating asbestos-containing materials in different school areas. Asbestos was mainly present in the vinyl floor coverings and in the asbestos-cement products (roofs, facades, and heating ducts). After the identification of the potential sources of exposure, several bulk and air samplings were performed in the areas where the contamination was suspected. All air samplings were collected on membrane filters and analyzed by phase contrast optical microscopy and scanning electron microscopy. During the course of the samplings, the schools were in operation and normal student activities took place. Most of the results provided no significant evidence of airborne asbestos fibers, although some dispersion was found in a few school buildings where, during the past years, monitoring and safety programs had not been implemented.

[An example of size characterization of synthetic vitreous fibers]. / Un esempio di caratterizzazione dimensionale di fibre vetrose artificiali.

BACKGROUND: The size characterization of synthetic vitreous fibres must be carried out to include or exclude them from classification as a carcinogen and to conduct in vivo and in vitro toxicity studies. The length weighted geometric mean diameter, together with its standard error, determines the toxicity of fibres according to Italian legislation relating to the provisions for classification, packaging and labelling of dangerous substances as formulated in the European Commission Directive 97/69/EC. Up to now there is no national or European guideline, which provides a technical procedure to obtain the size characterization parameters. OBJECTIVES: The aim of this paper was to measure the fibre size of some rock wool and ceramic fibre samples in order to estimate the length weighted geometric mean diameter and its standard error, and to calculate the related toxicity parameter. We also wanted to analyse whether the measured lengths and diameters were log-normally distributed or not. METHODS: We reduced the fibre length by the two most used techniques: cutting the rock wool fibres with a blade and pressing the ceramic fibre material in a die for infrared spectroscopy. Each sample was suspended in water by ultrasonic agitation and a small amount of it was filtered on a polycarbonate membrane. The diameter and length measurements of 300 fibres were carried out by a scanning electron microscope and the experimental data were analysed to calculate the main statistical parameters. The size distributions obtained for each sample were studied using the Kolmogorov-Smirnov test for normality and Q-Q plot. RESULTS: The fibre dispersion on the polycarbonate membrane area was suitable: there was a sufficient number of fibres to be measured without an excessive fibre overlapping. The main statistical parameters were calculated for two different cutting times (t = 20 min and t = 1 h) and two different applied forces (F = 1.2 t, corresponding to a pressure of 90 MPa, and F = 1.6 t, corresponding to a pressure of 120 MPa). For each substance the two sets of measurements were acquired by two different operators. This gave us an estimation of the variability of the calculated statistical parameters in the worse case (different applied forces or cutting times, and different operators). For the ceramic fibres only, one of the two operators carried out the measurements for both the applied forces to obtain more close information about the variability related to the method itself. The normality tests and the Q-Q plots showed that some of the data were far from having a lognormal distribution due to the tails of the distributions. CONCLUSIONS: Both fibre length reduction methods were effective, but the press method was found to be much easier and quicker. The data obtained showed that it is relatively easy to estimate the main statistical parameters related to the size characterization of synthetic vitreous fibres. Nevertheless, further studies must be carried out in order to better evaluate the method reproducibility and the variability of the parameters estimated by one and more operators, and to associate an error with the cancerogenicity parameter.