Polycyclic Aromatic Hydrocarbons Exposure Assessment in a Refractory Brick Production.

In a refractory brick manufacturing company a qualitative and quantitative determination of the sources of occupational exposure to polycyclic aromatic hydrocarbons (PAHs) was obtained in order to validate targeted hygiene measurements. The study included the assessment of PAHs contamination of work surfaces by wipe-sampling, cutaneous exposure by hand washing, contamination of personal protective equipments (gloves) by extraction in solvent, and airborne PAHs concentration in atmospheric samples. Biomonitoring was also carried out by measurement of urinary 1-hydroxypyrene (1-OHPU) in three groups of workers (packaging, production, and controls). The surface contamination sampling was performed in production, packaging, and in other departments (external area) in theory less contaminated by PAHs. Two different areas were identified within the production, one included surfaces that were regularly cleaned (A area) and one included data from non-cleaned surfaces (B area). To confirm the source of exposure, a clear correspondence was observed between the percentage of the single compounds in the binder and those measured in wipes and air samples. As far as the wipes are concerned, the concentrations of phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)pyrene (BaP), and the total PAHs mixture were higher in the B area than the A area of production. The same happened between the A area and the other two departments. According to results of the statistical analysis, these differences were significant. These results were confirmed by the hand washing data and the analysis of PPE. On the other hand, a marked difference does not exist between the packaging department and the external area. In air samples, the differences were much less evident with only higher concentrations of anthracene and total PAHs between production as a whole and the other two departments. Biological monitoring showed 1-OHPU values significantly higher in production workers than in packaging workers. In conclusion, the analysis of the wipes demonstrated that the production B area has a higher surface contamination compared to the production A area and the packaging department. In the absence of a significant difference in air concentrations of PAHs between A and B areas, this is attributable to surfaces not subject to cleaning. Results confirm that the measurement of surface contamination represents a valid tool for the assessment of sources of exposure to PAHs in the workplace.

[Chemical risk assessment in the leather goods producers: a comparison of the results obtained by measurements air concentration and algorithm ARChiMEDE]. / Valutazione del rischio chimico nel settore pellettiero: confronto dei risultati ottenuti con sistemi di campionamento attivo e algoritmo ARChi.MEDE.

The Italian legislation on chemical agents has undergone significant changes. The aim of the study was to compare the results obatained from an environmental investigation and the use of the ARChi.MEDE model The results of the survey were treated with the UNI EN 689/1997 that showed an acceptable result, while according to the use A.R.Chi.M.E.D.E. a significant risk was obtained. Actually the mathematical model assess workers exposure without considering in the calculation the specific preventive measures (personal protective equipment, training, uptake of pollutants at the source) as contemplated by law. So the mathematical model showed the need of preventive measures in the studied work place.

[Assessment of asbestos exposure via mineralogical analysis of bronchoalveolar lavage fluid]. / Stima dell'esposizione ad asbesto mediante analisi mineralogica del liquido di lavaggio broncoalveolare.

BACKGROUND: Mineralogical analysis of bronchoalveolar lavage fluid (BALF) by electron microscopy could be the most suitable method for assessing asbestos exposure. However, it has been claimed that there is not a standardized or systematic approach to the subject of mineralogical analysis. OBJECTIVES: The aim of the study was to evaluate mineralogical analysis of BALF by transmission electron microscopy (TEM) as biomarker of asbestos fibre load. METHODS: BALF was examined in 193 exposed workers (189 men and 4 women) and in 84 patients (65 men and 19 women) who underwent diagnostic fibreoptic bronchoscopy for various clinical purposes. Asbestos bodies (AB) in BALF were counted with a phase contrast microscope, while fibres were counted and analysed by TEM. RESULTS: Fibre counting by TEM showed a significant difference in the two populations (two tailed Mann-Whitney U test, p=0.0044), since it was positive in all exposed subjects. Only 75.1% of the exposed population was positive for asbestos bodies (AB). Subjects who had been exposed over a long time period had higher concentrations of fibres than subjects who had been exposed more recently probably because of higher exposure in the past. CONCLUSIONS: The study confirms the results of a previous study on a limited number of subjects. Fibre concentrations in BALF can be considered as a reliable biomarker of past asbestos exposure even after many years after cessation of exposure.

[Assessment of occupational skin exposure: proposal of a check-list]. / Valutazione dell'esposizione cutanea professionale: proposta di una check-list.

The dermal risk assessment requires simplified methodologies to understand the role played by the skin. The conceptual models proposed to this aim are founded on theoretical assumptions and experimental data, but their use in occupational settings shows many difficulties. For this end we have drawn up a check-list that includes six sessions and allows to obtain a preliminary dermal exposure evaluation subdivided on hazard bands.

[RISKOFDERM: European research project for assessment of occupational skin exposure to chemicals]. / RISKOFDERM: un progetto europeo per la valutazione dell'esposizione per via cutanea a tossici industriali.

OBJECTIVES: RISKOFDERM is a research project whose aim is to develop instruments to assess and manage occupational dermal exposure to chemical substances. METHODS: The research, funded by the European Commission, involves 15 Institutes from 10 member countries; it is a continuation of the Dermal Exposure Network experience and consists of four interrelated parts. The first phase (Qualitative survey) assumed that dermal exposure can be extrapolated from one compound to another when it is task-based: therefore six Dermal Exposure Operation units (DEOu) were defined that lead back to the variety of occupational dermal exposure conditions and an extensive Questionnaire was developed for on-site surveys to perform standard observations in selected working situations (scenarios). RESULTS: The Italian group, participating in the research, obtained a set of observations relating to two "scenarios" in different working sectors: asphalt, ceramic and pottery workers, spectacle decorators and paint production: the aim was to verify the validity of the methodology in assessing the risk of percutaneous absorption, time, frequency and extension of skin exposure. CONCLUSIONS: From the observations made it was shown that the perception of risk was poor; it is necessary to rationalise work organization, and train and inform the employees on the correct use of personal protection devices.

Dermal exposure assessment in occupational medicine.

The importance of dermal exposure has increased during the last few years, mainly because of the reduction of respiratory exposure to toxicants. Pesticides, aromatic amines and polycyclic aromatic hydrocarbons are considered to be the chemicals at highest dermal risk. In the occupational exposure limit lists of the American Conference of Governmental Industrial Hygienists (ACGIH) and of many countries, compounds that can be absorbed through the skin are identified by a skin notation. However, a generally accepted criterion for assigning skin notation does not exist. The recent attempts to develop health-based dermal occupational exposure limits (DOELs) have not been accepted, thus in practice their use has remained limited. To predict the systemic risk associated with dermal exposure and to enable agencies to set safety standards, penetration data are needed. Moreover, there is a need for a practical risk assessment model, particularly for small and medium-sized enterprises.

Asbestos exposure assessment by mineralogical analysis of bronchoalveolar lavage fluid.

Mineralogical analysis of bronchoalveolar lavage fluid (BALF) by electron microscopy can represent the most suitable method for assessing asbestos exposure. However, it has been claimed that no standardized or systematic approach to the subject of mineralogical analysis exists. This study aimed to evaluate BALF mineralogical analysis by transmission electron microscopy as biomarker of asbestos fiber load. BALF was examined in 108 exposed workers and 57 patients who underwent diagnostic fiberoptic bronchoscopy for various clinical purposes. Asbestos bodies in BALF were counted with a phase-contrast microscope. Fibers were counted and analyzed by transmission electron microscopy, which showed a significant difference between the two populations and positive results for all exposed subjects. Only 82.2% of the exposed population tested positive for asbestos bodies. Subjects with long-term exposure had higher concentrations of fibers than did those with more recent exposure, probably because of the higher workplace exposure levels in the past. The results of the study confirm that fiber concentration in BALF can be considered as a reliable biomarker of past asbestos exposure, even many years after the end of exposure.

Dermal exposure assessment of polycyclic aromatic hydrocarbons: in vitro percutaneous penetration from coal dust.

To understand the dermal uptake of chemicals bound to soil and dust, information on the neat substance is helpful but does not seem sufficient. Because of its content of polycyclic aromatic hydrocarbons (PAHs) coal is suspected to be carcinogenic. However, experimental carcinogenity studies on coal dust never succeeded in demonstrating a higher incidence of cancer in treated animals. The aim of the study was to assess dermal penetration through human skin of PAHs from coal dust. A sample of coal dust was grinded and sieved, using the particle size of < 30 microm. An in vitro static diffusion cell system validated by in vitrolin vivo comparison has been used to study dermal penetration through human skin of PAHs from coal dust compared with their percutaneous absorption as pure compounds. No percutaneous penetration of PAHs was observed in the cells where coal dust was applied, while dermal penetration was demonstrated for PAHs applied in an acetone solution. Results agree with the literature that PAHs are poorly absorbed through the skin from solids. Dermal risk assessment of PAHs should take into account not only the degree and the extent of skin contamination, but also their bioavailability, which is heavily influenced by the physico-chemical characteristics of the matrix.

[Dermal risk assessment in occupational medicine]. / La stima del rischio cutaneo in medicina del Lavoro.

The importance of dermal exposure has increased during the last few years mainly because of the reduction of respiratory exposure to toxicants. Pesticides, aromatic amines and polycyclic aromatic hydrocarbons are considered to be the chemicals with highest dermal risk. In the occupational exposure limit lists of the ACGIH and of many countries compounds that can be absorbed through the skin are identified by a skin notation. Usually the skin notation indicates that the percutaneous absorption of the chemical can contribute to the body burden. However, a generally accepted criterion for assigning skin notation does not exist. When it is possible to make standardized measurements of dermal exposure, it will be possible to develop Dermal Occupational Exposure Limits (DOEL) with which such measurements can be compared to enable a regulatory approach in the risk assessment field. However, the recent attempts to develop health-based DOELs have not been accepted, thus in practice their use has been limited.

Percutaneous penetration studies for risk assessment.

During the last few years the general interest in the percutaneous absorption of chemicals has increased. It is generally accepted that there is very few reliable quantitative and qualitative data on dermal exposure to chemicals in the general population and in occupationally exposed workers. In order to predict the systemic risk of dermally absorbed chemicals and to enable agencies to set safety standards, data is needed on the rates of percutaneous penetration of important chemicals. Standardization of in vitro tests and comparison of their results with the in vivo data could produce internationally accepted penetration rates and/or absorption percentages very useful for regulatory toxicology. The work of the Percutaneous Penetration Subgroup of EC Dermal Exposure Network has been focussed on the standardization and validation of in vitro experiments, necessary to obtain internationally accepted penetration rates for regulatory purposes. The members of the Subgroup analyzed the guidelines on percutaneous penetration in vitro studies presented by various organizations and suggested a standardization of in vitro models for percutaneous penetration taking into account their individual experiences, literature data and guidelines already in existence. During the meetings of Percutaneous Penetration Subgroup they presented a number of short papers of up to date information on the key issues. The objective was to focus the existing knowledge and the gaps in the knowledge in the field of percutaneous penetration. This paper is an outcome of the meetings of the Percutaneous Penetration Subgroup and reports the presentations on the key issues identified throughout the 3-year duration of the Dermal Exposure Network (1997-1999).

Dermal exposure assessment of polycyclic aromatic hydrocarbons: in vitro percutaneous penetration from lubricating oil.

OBJECTIVES: Percutaneous penetration of polycyclic aromatic hydrocarbons (PAHs) is affected by various factors connected to exposure conditions. The nature of the matrix, such as that of oil, can strongly affect their percutaneous penetration. Risk assessment should consider these effects. We examined the effect of matrix on percutaneous penetration of PAHs, particularly that of lubricating oil. METHODS: The test apparatus consisted of an in vitro static diffusion cell system using full-thickness monkey (Cercopithecus aetiops) skin as the membrane and saline solution with gentamycin sulfate and 4% bovine serum albumin as receptor fluid. Chemical analysis of PAHs in the samples obtained from cells was carried out by inverse-phase HPCL, and the results were read by spectrofluorimetry. RESULTS: Comparing the penetration of 13 PAHs from a lubricating oil and from acetone solution with artificial sweat resulted in a significantly slower passage from the oil matrix for acenaphthene, anthracene, phenanthrene, fluoranthene, naphthalene, pyrene, fluorene (Mann-Whitney U test, P < 0.05). No significant differences in the passage were found for chrysene because, in the test with oil, its concentration was very often below the detection limit. For benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene it was possible to demonstrate a passage through the skin only when compounds were applied in acetone solution with artificial sweat. CONCLUSIONS: The results of the study suggest the necessity of dermal penetration data relevant for risk assessment, obtained under experimental conditions similar to the real exposure conditions.

Multiroute exposure assessment and excretion of urinary metabolites of fenitrothion during manual operations on treated ornamental plants in greenhouses.

The results of environmental and biological (five subjects) monitoring of exposure to fenitrothion during manual operations on treated ornamental plants in greenhouses are reported. Urinary excretion [GM (GSD)] of alkylphosphates [dimethylphosphate (DMP) + dimethylthiophosphate (DMTP)] (nmol/g creat) was 244.8 (1.8), 174.0 (2.0), and 354.4 (1.6) respectively, on the first (Monday), third (Wednesday), and fifth (Friday) days of work. These levels were not significantly higher than those recorded in a control group (21 subjects) in which urinary excretion [GM (GSD)] of DMP + DMTP was 102.8 (4.2) nmol/g creat. Air concentrations of fenitrothion (nmol/m3) ranged from 45.5 to 81.2 on Monday, 17.3 to 27.1 on Wednesday, and 9.7 to 19.1 on Friday. Dose estimates showed that the respiratory-absorbed doses of fenitrothion accounted, on the average (GM), for 94.7%, 93.1%, and 91.5% of the total absorbed dose on Monday, Wednesday, and Friday, respectively. Multiple regression analysis showed a significant correlation (r2 = 0.595) between urinary excretion of DMP + DMTP, respiratory-absorbed dose, and skin-absorbed dose, estimated on Monday and Wednesday. Total estimated absorbed doses did not exceed the acceptable daily intake for fenitrothion. Serum and erythrocyte cholinesterase activities were not significantly different before and after exposure.