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Indoor air is a complex mixture of chemicals and airborne particles. Volatile Organic Compounds (VOC), a broad class of chemicals including diverse compounds such as Aldehydes, Terpenes, Aromatic and Aliphatic Hydrocarbons and Halogenated Volatile Organics, are an important category of indoor air pollutants. The evaluation of exposure to low doses of Chloroform and Benzene through the measurement of Chloroform and Benzene in urine was performed. Results show that biological monitoring may be helpful in indoor environmental studies in non occupational situations.

According to act n. 626, individual assessment of fitness and absence of contraindications for carrying on a job is fundamental. We considered a group of 44 Urban Police officers (36 males, 8 females), age 39.7 +/- 9.1, whose principal job requirement is a good energetic and motor availability, for a fitness evaluation through a submaximal treadmill test, with subsequent steps of 6 minutes. During the test, physiological variables (VO2, VE, QR through a metabograph, Hr trough an Ec-monitor and Pa through a manual sphygmomanometer) and subjective evaluations of fatigue and dyspnea were monitored. Studying the individual variables trend it was possible to identify the critical metabolic level that was easily tolerated by each individual. This level, an average of 6.8 MET corresponding to a heavy activity, is an endurance predictor and can be utilized in subsequent controls.

Two different groups of workers, involved in production or formulation of chlorotriazine herbicides during the last 10 years, have been retrospectively studied for occurrence of diseases related to the exposure to Atrazine, Simazine, Propazine, and Terbuthylazine. A control group has been selected between clerical workers of the same plants. Subjects exposed to the different compounds have been studied for inhalator and dermal exposure by active sampling, skin pads, and hand washings; samples have been further processed and specifically analysed. Urines have been studied for the presence and concentrations of mono and bidealkylated triazine metabolites. Exposure data have been collected during the last five years and extrapolations have performed for exposures in the preceding years. Clinical finding and laboratory data for all workers have been obtained from medical surveillance records. Data available for the last 10 years have been evaluated to highlight possible differences between the investigated groups.

We have considered the opportunity of using some inert vapours (2-3 Dimethylbutane, 2 Methylpentane, n-Hexane) to measure the pulmonary capillary blood flow (Qc). The measurements were performed by means of a gas chromatograph connected with a mass spectrometer. The alpha values (Bunsen absorption coefficients) measured by a constant pressure method (multiple equilibration methods) were reported. Qc was measured in 14 healthy subjects at rest and in 5 subjects during exercise (25 and 50 watt by means of a cyclo ergometer, steady state test) (rebreathing method). The method used allow multiple measurements of Qc during the same exercise test.

51 workers, occupationally exposed to anaesthetic gases and vapours (nitrous oxide, halothane, and isoflurane), were studied monitoring their environmental and biological exposure. Moreover, they were tested for visual reaction times and neurobehavioural batteries. There was no evidence of important neurotoxic effects nor of neurobehavioural problems with low concentrations of anaesthetics.

This paper reports the data of nitrous oxide (N2O) environmental pollution in 269 operating rooms of 47 hospitals in Italy in 1989-91. In 40% of the operating rooms the N2O concentrations are lower than 50 ppm, limit value proposed by Health Council for new operating rooms. In 65.4% of the operating room studied, N2O mean environmental concentrations are lower than 100 ppm, value proposed by the above-mentioned Health Council as limit value for the already existing operating rooms. Concerning the biological monitoring, the authors report several N2O data in urine (2193), whose levels confirm the data obtained with environmental monitoring. The authors believe that they presently have reliable methods to perform biological and environmental monitoring: the two techniques are complementary in the assessment of the exposure. The method of measuring N2O concentrations as exposure index, both for the environmental and biological monitoring, is considered very useful to simplify the performance of the analyses. In order to assess exposure more precisely, it is however necessary also to determine the environmental and/or biological measure of the other different anaesthetics used.

The urine/air and blood/urine partition coefficients (lambda) of 43 commonly employed organic solvents (Aliphatic, Cyclic, Aromatic and Halogenated Hydrocarbons, Ketones, Alcohols and Esters) are reported. The analyses were performed by the multiple equilibration method (constant pressure method) using a Hewlett-Packard 5880 gas chromatograph. The lambda values proposed can be employed in the field of biological monitoring of subjects occupationally exposed to solvents vapors.

A simple programme in basic language is formulated, which can be used with a personal computer, to evaluate the minimum and maximum sampling time of personal passive samplers at given concentrations of solvents. It is possible to evaluate also the sampler's response time to the peak concentration of the solvent and, once an arbitrary sampling time has been chosen, it is possible to know the concentration range to get exact determinations.

A list of industrial solvents largely employed and produced in Italy (and somewhere else too) is presented. Using two methods previously described, blood/air partition coefficient of such solvents have been measured. Then a discussion is made about the possibility of their employment in the field of biological monitoring of subjects professionally exposed to solvent vapours.

The authors examined the blood of 856 subjects (377 smokers and 479 non smokers) in order to evaluate the levels of Methemoglobin (MetHb) in relationship to tobacco smoke. The Methemoglobin, Carboxyhemoglobin, Percent Oxyhemoglobin and Total Hemoglobin were measured using an automated spectrometer (IL 282 CO - Oximeter). The authors found that the levels of MetHb in the smokers exceed that in the non smokers: in fact the level of MetHb in the smokers (% MetHb = 0.63) was significantly greater than in the non smokers (% MetHb = 0.56), unlike what was reported in literature. The levels of Carboxyhemoglobin in the blood has been shown to be a useful marker of tobacco smoke absorption: a close relationship exists between COHb and cigarette smoking.

The long-term occupational exposure to inhalation anaesthetics might represent a health hazard; mainly it may have an adverse effect on the reproductive outcome. Nitrous oxide is the anaesthetic employed in the largest amount during general anaesthesia and it can be used as an indicator of occupational exposure to all the components the mixture; but if the pattern of dispersion of them (when leaking into the operating theater) are not the same, two indicators should be used: N2O (gas) + another component the mixture (vapour). Our results concern practically 5 points: --Analysis of N2O by means of a diffusive personal sampler (comparison with a conventional sampling method) --Analysis of N2O in urine collected after 4 hours of exposure during routine anaesthetic work (headspace method) --Comparison of environmental and biological data concerning N2O --Comparison of environmental and biological data concerning a component of the anaesthetic mixture, forane --Proposal of biological exposure indices for nitrous oxide and forane. A close relationship between air and urine was found in 363 subjects occupationally exposed to N2O and 45 subjects exposed to forane (r: 0.95 and 0.90 respectively). On the basis of such a relationship the biological exposure index for N2O corresponding to an ambient concentration of 100 ppm (European limit) turned out to be 55 micrograms/L; the ones for forane corresponding to ambient concentrations of 2 or 10 ppm are respectively 3.4 or 14.5 micrograms/L (urinary concentrations in samples collected after 4 hours of exposure).

Alveolar (CA) and mixed expired air (CE) acetone concentrations were measured in 15 healthy volunteer subjects, exposed to acetone (CI) in an exposure chamber (exposure range: 48-565 mg/m3) both at rest and during exercise (50 W). The Relative Uptake (R = 1-CE/CI) was 0.54 at rest (120' and 240') and 0.55 during exercise (120', 50 W). Ca:CI ratio was 0.24 at rest. CE:CI and CA:CI ratio was constant throughout the exposure time, both at rest and during exercise.

The AA describe the realise of an open circuit exposure chamber: it enables to reach solvent concentration levels that are continuously monitored and kept within the limits of acceptability. The room can be employed in studies and experimental researches on the respiratory absorption levels of airborne pollutants in man. The following data are reported: on microclimatic parameters, on the monitoring of CO2 concentration in the room when someone is inside, on the solvent concentration measures in different points of the room, on the monitoring of the quickness to reach the steady-state and wash-out in the room, on the available concentration ranges.

The physical demand in the workplaces can be different depending on each specific job. This involves that workers exposed to the same environmental level of an airborne can absorb different amounts of it depending on their pulmonary ventilation. Starting from the relationship between the uptake (U) and the urinary concentration (Cu) of 6 solvents (Acetone, Styrene, Xylenes, Toluene, Methylchloroform, Tetrachloroethylene) and from the equation expressing their lung uptake the expected values of a biological index after a given time of exposure can be derived. Such values are a function not only of the environmental levels of exposure (CI) but also of the pulmonary ventilation (V) (V--dependent solvents) and of the retention index (R) (V--R--dependent solvents).

A laboratory study, using generated atmosphere containing 0.14/23.3 mg/m3 of Benzene, was conducted to adapt an existing industrial hygiene monitoring method for measuring low concentrations of Benzene. This method was developed to determine concentrations of Benzene in the ambient air and around refinery/petrochemical plant. The air sample is collected on a diffusive personal sampler (Zambelli-TK 200) and analyzed by desorption with a mixture of methylene chloride and ethyl acetate followed by quantification using HPLC-Fluorescence detector. The method used did not detect aliphatic or alicyclic hydrocarbons. The HPLC-Fluorescence method is compared with a gas chromatographic method that uses capillary column and flame ionization detection after a collection of air sample on a Carbotrap 100 tube and following thermal desorption.

Oxygen consumption (VO2) and other cardiorespiratory parameters (pulmonary ventilation, tidal volume, respiratory rate, alveolar ventilation, heart rate) have been measured in 10 healthy subjects (20-40 years old) while performing 3 respiratory exercise (abdominal muscles reinforcement, scapulo-humeral articulation movements and chest expansion). The performance of the abdominal muscles reinforcement exercises requires the highest oxygen consumption. The 3 exercises decrease the "Dead space/Tidal volume" ratio and increase the alveolar ventilation.

Fifteen human volunteers were exposed to methyl ethyl ketone (MEK) vapor at 11.9-621.8 mg/m3 for a period of 2 to 4 hours at rest (ten cases) and during light physical exercise (five cases). Subsequently 78 workers occupationally exposed to MEK in a manufacture of leather suitcases (median value: 75.5 mg/m3; geometrical standard deviation: 3.12 mg/m3; range: 6-790) were studied. The analyses were performed by means of a Gas Chromatograph (GC) Hewlett-Packard 5880 A connected with a Mass Selective Detector (MSD). The relative uptake (R) of MEK was about 0.54 (standard deviation: 0.05) and it keeps practically constant either at rest or during light effort (V < 30 L/min). A linear relationship existed in the experimentally exposed subjects between urinary concentration (Cu) and amount of MEK absorbed (U) (Cu = 3.05 x U-162.1; r = 0.95; n = 15) (Cu = micrograms/L; U = mg). Both in the experimentally exposed subjects and in the occupationally exposed workers, the urinary concentration of MEK shoved a linear relationship to the corresponding environmental time-weighted average concentration (CI). The correlation coefficients (r) were 0.93 in occupationally exposed subjects (regression equation: Cu = 0.004 x CI + 0.118; n = 78); Cu = mg/L; CI = mg/m3) and more than 0.93 in experimentally exposed groups. The findings indicate that the urinary concentration of MEK can be used as an appropriate biological exposure indicator.(ABSTRACT TRUNCATED AT 250 WORDS)

A new alveolar air sampler is described and tested; it can be used in monitoring subjects exposed to gas and vapours in their working places. The tests were made under different experimental conditions, using both vapours of industrial solvents as acetone, ethanol, trichloroethylene, methyl ethyl ketone, n-hexane, ethyl acetate and respiratory gas (O2, CO2).

Solubility coefficients of 21 organic industrial solvents of toxicological importance are presented. Using a multiple phase equilibration method, blood/air partition coefficients (lambda) of such substances have been measured. The lambda-values proposed can be employed in the field of biological monitoring of subjects professionally exposed to solvent vapours.

The authors report the parameters which rule the absorption and elimination of polluting solvent vapours in exposed subjects (Ventilation, Pulmonary Capillary Flow, Solubility Coefficients, Environmental Concentrations, Exposure Times). These parameters are included in the equations showing the absorption and elimination indexes and lung clearances. Some methods to measure the Solubility Coefficients of inert gases in biological media and the values referring to 51 industrial solvents, commonly employed or important from the toxicological point of view, are described. Finally the Authors report some experimental results obtained in exposure chamber on volunteers, and in occupationally exposed subjects directly in workplaces. The results are discussed stressing their practical usefulness in the field of biological monitoring, industrial hygiene and in preventive medicine.

The Authors describe some methods (at constant pressure and constant volume) which can be used when solubility coefficients of gas and vapours in liquids (water, blood, oil etc.) are to be measured; they are easily performed methods, which are based on the validity of Henry's law.

Bronchial asthma has been defined as a state of airway obstruction of variable degree correlated casually with exposure to volatile dusts, gases, vapours or fumes in the working environment. In this review we considered the causes of occupational asthma, the diagnosis, the pattern of asthmatic reactions and their mechanism, the predisposing factors, the epidemiology, the prognosis and finally the cure and prevention (review article, 165 references).

The urinary concentration of some solvents (acetone, cyclohexane, 1,2 dichloropropane, n-hexane, methyl ethyl ketone, perchloroethylene, styrene, toluene, 1,1,1, trichloroethane) was measured by means of a gas chromatography Hewlett-Packard 5890 supplied with a flame ionization detector (GC-FID, DANI HS 3950). The coefficient of variation of the method was lower than 5%. The sensitivity of the GC-FID was very similar to what of mass spectrometer detector (GC-MSD, HP 5970 A).

The aim of the present work is to determine p-DCB concentration in the urine of exposed workers and to verify a possible correlation with the environmental exposure. The authors studied four subjects exposed to different p-DCB environmental concentrations during a working week. The measurement of the substances was performed by means of a Hewlett-Packard 5880 A gas-chromatograph supplied with a Hewlett-Packard 5970 A Mass Selective Detector. The analysis was performed by a head space method (after determining the urine/air partition coefficient (lambda) by the multiple phase equilibration method). The lambda value (urine/air) of p-DCB is 10.8. The Authors found a significant relationship between the difference of p-DCB urinary concentration at the beginning and end of a daily work delta Cu (microgram/l) and the p-DCB environmental concentration C-I (mg/m3) (r = 0.64) (P less than 0.01); delta Cu = 0,48C-I + 15.61. We found that with an environmental exposure of 44.7 mg/m3 median value (geometrical deviation 1.15) there is an increase of p-DCB concentration in the urine of workers during the working week. For a daily environmental exposure of 450 mg/m3 (ACGIH TLV, 1984), we think that it is possible to propose a Biological Exposure Index (B.E.I.) of 250 micrograms/l as difference between beginning and end of a daily work.

The authors describe one case of Vitiligo in a worker employed in a firm for the exploitation of underground energetic products. The disease occurred after contact with the mud used for the drilling containing aromatic, aliphatic and chlorinated hydrocarbons. The possible occupational cause of the disease, as more solvents in the mud have the structure of aromatic hydrocarbons is discussed.