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This study investigated the exposure to organohalogens compounds in drinking water from 9 Italian towns (Udine, Genova, Parma, Modena, Siena, Roma, L'Aquila, Napoli and Catania). Overall, 1199 samples collected from 72 waterworks were analyzed. THMs, trichloroethylene and tetrachloroethylene were evaluated using the head-space gas chromatographic technique (detection limit of 0.01 microg/l; chlorite and chlorate analysis was performed by ion chromatography (detection limit of 20 microg/l). THMs were evidenced in 925 samples (77%) (median value: 1.12 micro/l; range: 0.01-54 mciro/l) and 7 were higher than the THMs Italian limit of 30 microg/l. Chlorite and chlorate levels were higher than the detection limit in 45% for chlorite and in 34% for chlorate samples; median values were 221 microg/l and 76 microg/l, respectively. Chlorite values were higher than the chlorite Italian limit (700 microg/l) in 35 samples (8.7%). Trichloroethylene and tetrachloroethylene were measured in 29% and 44% of the investigated samples and showed values lower than the Italian limit (highest levels of 6 microg/l and 9 microg/l, respectively). The low levels detected of THMs, trichloroethylene and tetrachloroethylene have no potentials effects on human health, whereas, the levels of chlorite and chlorates should be further evaluated and their potential effects for the populations using these drinking waters, better understood.

Epidemiological studies to evaluate the association between environmental exposure to risk factors and negative health effects often use population level aggregated data to measure exposure, but do not consider personal characteristics that may affect the degree of exposure at the individual level. The aim of this study was to evaluate the validity and reproducibility of a questionnaire specifically designed to measure individual oral, inhalation and transdermal exposure to disinfection byproducts in drinking water. Reproducibility of the questionnaire was evaluated by administering the questionnaire twice, in different time periods, to the same subjects. On the other hand, validity was tested by comparing responses to the questions with information contained in diaries filled out by the subjects daily over a period of one week (gold standard). Questionnaire reproducibilty and validity were both found to be very good, as shown by high Spearman's correlaton coefficients, Intraclass correlation coefficients (ICC), kappa concordance coefficient, sensibility and specificity. The use of a questionnaire such as the one evaluated in this study may be a valuable aid when conductin epidemiological studies to assess individual environmental exposure to risk factors found in drinking water and to explain the effect of such factors on human health.

Emergency departments records from 33 hospitals were reviewed to disclose work-related injuries occurred in teen-subjects living in 14 Italian cities. During January-June 2000, 317 work-related injuries were reported. Male subjects, 17 year old, working in the industrial field, resulted the most affected, probably due to the fact that among young workers this sex and age class is the most represented one. Cluster analysis identified two groups of work-related injuries: one includes mainly transportation injuries causing lower extremities or multiple body sites traumas. The other is more strictly related to specific working tasks and includes mostly traumas and cut wounds in hand/wrist and head, together with eye lesions. A more intensive supervision on the use of protective equipment, a more appropriate training in hazard recognition and safe work practices, including operation of vehicles in the work site, must be implemented to reduce work-related injuries.

Chlorination by-products (CBPs) in drinking water have been associated with an increased risk of adverse pregnancy outcomes, including small for gestational age at term (term-SGA) and preterm delivery. Epidemiological evidence is weakened by a generally inaccurate exposure assessment, often at an ecological level. A case control study with incident cases was performed in nine Italian towns between October 1999 and September 2000. A total of 1,194 subjects were enrolled: 343 preterm births (26th-37th not completed week of pregnancy), 239 term-SGA (from 37th completed week, and weight less than the lowest 10th percentile) and 612 controls. Exposure was assessed both by applying a questionnaire on mothers' personal habits during pregnancy and by water sampling directly at mothers' homes. Levels of trihalomethanes (THMs) were low (median: 1.10 microg l(-1)), while chlorite and chlorate concentrations were relatively high (median: 216.5 microg l(-1) for chlorites and 76.5 microg l(-1) for chlorates). Preterm birth showed no association with CBPs, while term-SGA, when chlorite levels > or =200 microg l(-1) combined with low and high levels of inhalation exposure are considered, suggested a dose-response relationship (adjusted-Odds Ratios (ORs): 1.52, 95%CI: 0.91-2.54 and 1.70, 95%CI: 0.97-3.0, respectively). A weak association with high exposure levels of either THMs (> or =30 microg l(-1)), or chlorite or chlorate (> or =200 microg l(-1)) was also found (adjusted-OR: 1.38, 95%CI: 0.92-2.07). Chlorine dioxide treatment is widespread in Italy; therefore, chlorite levels should be regularly and carefully monitored and their potential effects on pregnancy further evaluated and better understood.

74 mineral natural water samples and 56 samples of different commercial drinks have been analysed by head-space chromatography in order to evidence the presence of volatile halogenated organic compounds (VHO). Trihalomethanes (THM) as drinking water chlorination by-products and trichloroethane, carbon tetrachloride, trichloroethylene and tetrachloroethylene as ubiquitarious substances have been investigated. The presence of VHO has been evidenced in 20,3% of mineral natural water samples and in the 58,9% of the commercial soft drinks: this latest group has usually shown higher levels of the investigated compounds. The results of the present study has been compared with a similar study performed in 1991 in the same area: the VHO values observed in the present study appear to be lower than those obtained in the previous study.

We studied the reliability of biologic indices for monitoring perchlorethylene (PCE) exposure at low environmental solvent concentrations. Environmental monitoring was performed by personal sampling, biologic monitoring by measuring PCE in alveolar air (PCE-Alv), blood (PCE-B), and urine (PCE-U) in 26 low-exposed dry-cleaners. Correlation coefficients (r) between environmental PCE and PCE-B, PCE-Alv, and PCE-U were 0.94, 0.81, and 0.67 respectively. A high correlation was also found among biologic indices: r value was 0.96 between PCE-B and PCE-Alv, 0.95 between PCE-B and PCE-U, and 0.87 between alveolar PCE-Alv and PCE-U. The examined biologic indices proved sensitive enough for biologic monitoring of low exposure to PCE and can give substantially similar information in terms of exposure evaluation. PCE-Alv offers some advantages because it correlated better with exposure and is analytically simpler.

The authors have assessed the activity of a complex division (three wards) at the Modena General Hospital. The parameters used were DRG indicators: Case-Mix Index; Performance Index and Resources Index. It is a in-house hospital analysis, since the benchmark is based on the three units average figures. The analysis covers 1479 patients hospitalized during the first 6 months of the year 2000. The authors have taken into account overall DGRs, surgical DGRs and recurrent DGRs. Making allowance for the limits of such comparison, the study shows some differences as regards efficiency and cost-curbing policies, with the surgical unit having the largest and most diversified number of cases.

The Authors report data about the presence of Disinfection By-Products (DBPs) and other halogenated compounds in drinking water samples collected in the areas of Modena and Parma (20 water supplies). Trihalomethanes, chlorite and chlorate (only in water samples treated with chlorine dioxide), and halogenated compounds were investigated. On the whole, trihalomethanes were evidenced in the 85% of the samples (n. 285) at low levels, while chlorite and chlorate were present in the 67% and 63% of the treated samples with chlorine dioxide (257 samples). Chlorite mean and median values were 225.70 microg/l and 136.75 microg/l respectively, ranging from 20 to 2000 microg/l. Chlorate concentrations were lower than chlorite: the mean value was 102.93 mg/l, while median level was 50 microg/l (range: 20-1500 microg/l). The high concentrations of chlorite and the wide range of values within each municipality plant in Modena and Parma suggest to investigate further in order to evaluate the human exposure in drinking water thoroughly.

Chlorination By Products (CBPs) in drinking water have been associated with an increased risk of adverse pregnancy outcomes, such as small term birth (STB) and preterm delivery. Up to date epidemiological evidence is weakened by a generally inaccurate exposure assessment, often at an ecological level: in this study the exposure is evaluated at the individual level. A case control study with incident cases was performed in Modena between October 1999-September 2000. 332 subjects were enrolled: 93 preterm births (26th-37th week of pregnancy), 73 STB (from 38th week, and weight less than the lowest 10th percentile) and 166 controls. Exposure was assessed both by applying a questionnaire on personal habits and by personal water sampling directly at subjects' home. THMs were analysed in all samples, chlorite and chlorate in water samples treated with chlorine dioxide. Subjects usually drinking tap water were few (5.2%): most of them were living in areas supplied by water treated with chlorine dioxide (87%). Levels of THMs were low (mean: 0.73 microgram/l), while chlorite and chlorate concentrations were relatively high (mean: 217.8 microgram/l for chlorites and 95.2 microgram/l for chlorates). Preterm birth did not show any significant association with CBPs, while STB appeared significantly associated, after adjusting for many potential confounders, with CBPs induced by chlorine dioxide treatment, especially with levels of chlorate higher than 200 microgram/l (OR: 4.7; 95%CI: 1.15-19.72). The association between STB and chlorate must be investigated further as the number of water utilities applying chlorine dioxide as disinfection treatment is increasing.

Work related injuries, above all those involving young people, are an important health and social issue, even though up to now small attention has been deserved in spite of the presence of about 68 workers per 1000 young people and the occurrence of 27400 injures in young people in 2000 in Italy. This study was aimed at improving the knowledge on work related injures occurring in Modena in 14-17 year old subjects in the period January-June 2000. A descriptive epidemiological study was carried out. Information was collected at the two emergency departments operating in Modena by checking hospital and INAIL records. Injures were defined as events caused by a violent external cause producing one or more lesions. Injuries were defined as work related when occurring during working activities or "in itinere". Work related injures and other injures were compared using the different statistical methods. Work related injuries occurring in young people during January-June 2000 in Modena were 76 (6-month incidence: 1.5 per 100 subjects of the same age) and represent 8.5% of all injuries. The most involved subjects were 17 year old males working in the industrial field, and in most cases prognoses were lasting less than 8 days. A Cluster Analysis identified two types of injures: the "in itinere" ones which resulted similar to the road accidents, both for body sites involved and for the way of occurrence and the injuries occurring at the working place characterised by a high frequency of lesions concerning hand, head, above all eyes. The study showed a remarkable incidence of work related injuries among 14-17 year old subjects in Modena in the first 6 months of 2000. Nevertheless many difficulties in finding information raised during the survey: a higher accuracy and completeness in collecting and recording of the data is needed to better define the epidemiological aspects of this issue.

Background: To evaluate associations between exposure to disinfection byproducts in drinking water and adverse birth outcomes, personal exposure to disinfection byproducts must take into consideration multiple routes of exposure., Methods: We assessed the reproducibility and validity of a questionnaire measuring water consumption, showering and bathing habits, use of chlorine-based products, and swimming pool attendance in 237 pregnant Italian women enrolled between June and December 1999. The questionnaire was completed during the last trimester of pregnancy (preQ) and again a few days after delivery (postQ). Data from postQ were compared with a 7-day diary completed during the last trimester., Results: According to postQ, total water intake was 2.6 liters per day, whereas tap water intake was 0.6 liters per day. Intraclass correlation coefficients of postQ compared with preQ were 0.85 for tap water daily intake and 0.77 for duration of showering and bathing. Pearson's correlation coefficients were 0.84 for tap water daily intake, 0.81 for frequency of showering, and 0.94 for bathing. The kappa statistics were 0.76 (95% confidence limits = 0.68, 0.85) for use of domestic chlorine-based products and 0.82 (0.70, 0.94) for indoor swimming. Pearson's coefficients for postQ compared with the diary were 0.78 for tap water daily intake, 0.62 for frequency of showering, and 0.64 for bathing. Compared with the diary, the sensitivity and specificity of postQ in assessing indoor swimming were 75% and 90%, respectively., Conclusions: The questionnaire appears to be a valid and reliable method for assessing exposure to disinfection byproducts in the last trimester of pregnancy.

The study evaluated occupational exposure to trihalomethanes (THMs) in indoor swimming pools. Thirty-two subjects, representing the whole workforce employed in the five public indoor swimming pools in the city of Modena (Northern Italy) were enrolled. Both environmental and biological monitoring of THMs exposure were performed. Environmental concentrations of THMs in different areas inside the swimming pools (at the poolside, in the reception area and in the engine-room) were measured as external exposure index, while individual exposure of swimming pool employees was estimated by THMs concentration in alveolar air. The levels of THMs observed in swimming pool water ranged from 17.8 to 70.8 microg/l; the mean levels of THMs in ambient air were 25.6+/-24.5 microg/m3 in the engine room, 26.1+/-24.3 microg/m3 in the reception area and 58.0+/-22.1 microg/m3 at the poolside. Among THMs, only chloroform and bromodichloromethane were always measured in ambient air, while dibromochloromethane was detected in ambient air rarely and bromoform only once. Biological monitoring results showed a THMs mean value of 20.9+/-15.6 microg/m3. Statistically significant differences were observed according to the main job activity: in pool attendants, THMs alveolar air were approximately double those observed in employees working in other areas of the swimming pools (25.1+/-16.5 microg/m3 vs. 14.8+/-12.3 microg/m3, P < 0.01). THMs in alveolar air samples were significantly correlated with THMs concentrations in ambient air (r = 0.57; P < 0.001). Indoor swimming pool employees are exposed to THMs at ambient air levels higher than the general population. The different environmental exposure inside the swimming pool can induce a different internal dose in exposed workers. The correlation found between ambient and alveolar air samples confirms that breath analysis is a good biological index of occupational exposure to these substances at low environmental levels.

An outbreak of nosocomial legionnaires' disease in a hospital of Northern Italy is described, together with the epidemiological survey and the control measures adopted. Two patients developed Legionella pneumophila (serogroup 1) pneumonia, one (immunodepressed) died. The Task Group organised by the Health Service excluded other previous nosocomial infections, and made controls on patients and personnel of at risk units (all negative). An intensive programme of environmental sampling and educational activities on personnel have been carried out. The environmental surveillance revealed that the centralised hot water distribution system of the hospital was colonised with Legionella. Shock heating and hyperchlorination of water were applied, which reduced the number of contaminated sites short term, but recolonisation took place two months later. We underline the difficulties encountered to control Legionella by active surveillance of water quality; once the system is contamined, Legionella eradication may be difficult and expensive, and cases of hospital-acquired legionnaieres' disease are likely to occur.

The incidence of legionella infection in Europe overall in 1997 was 3.9 cases per million population, with the lowest rates reported by Malta and Norway and the highest by Denmark. Ninety cases were reported in Italy (1.5 cases/million), 20% of which were

Progression of perchloroethylene-induced color-vision impairment was studied in 33 dry-cleaner workers at 12 establishments in Modena, Italy. In an initial survey, we evaluated exposure with personal passive samplers, and we assessed color vision with the Lanthony D-15 desaturated panel. Two years later, workers were reexamined. In 19 workers (subgroup A), exposure to perchloroethylene had increased (median of 1.7 ppm versus 4.3 ppm, respectively), whereas in the remaining 14 workers (subgroup B) exposure was reduced (2.9 ppm versus 0.7 ppm, respectively). Color vision worsened in subgroup A, but no vision changes were apparent in subgroup B. The results indicated that an increase in exposure during a 2-y period, even if slight, can cause color vision to deteriorate. A similar slight reduction in exposure did not lead to color-vision improvement; perhaps this lack of improvement resulted from (a) an insufficient reduction in exposure, (b) an insufficient reduction in duration of exposure, or (c) irreversible perchloroethylene-induced color-vision loss.

We carried out a survey in 16 libraries of the University of Modena, Northern Italy, to assess the indoor exposure to volatile organic compounds (VOCs), including formaldehyde, and total dusts. Data were collected on the main structural characteristics of the buildings; indoor microclimate parameters, such as temperature, relative humidity and ventilation rate were measured and air samples taken inside and outside the libraries. The mean value of total dusts was 190 +/- 130 microg/m3 with a wide range of values. Formaldehyde was found in only ten out of 16 libraries and the indoor concentrations ranged from 1.70 to 67.8 microg/m3 with an average value of 32.7 +/- 23.9 microg/m3. On the whole, VOCs were present in all the libraries investigated with an average value was 433 +/- 267 microg/m3 (range 102-936 microg/m3). No correlation was found among VOCs, formaldehyde and total dusts nor was a significant association observed with microclimatic parameters or the structural characteristics of the buildings. The general situation found in this study suggests no major problems related to indoor pollution. However, some of the pollutants investigated such as total dust and total VOCs deserve further investigation. It is important to identify the possible sources of contaminants and to define the relationship between indoor and outdoor levels of pollutants more accurately, taking into account the effects of air recycling due to natural ventilation systems.

Perchloroethylene (PCE) is the most widely used solvent in dry-cleaning; it is toxic to the liver, kidney and central nervous system and may be a human carcinogen. PCE levels in the ambient air of dry-cleaners' homes were measured, and samples of end-exhaled air (alveolar air) from subjects who were not themselves occupationally exposed, but who were members of the household of dry-cleaners were compared with samples from the general population. Thirty apartments were visited housing dry-cleaners and their families, and located well away from the dry-cleaning premises. Indoor air samples and alveolar air samples were collected contemporaneously from the dry-cleaners (36) and members of their household (34). The same sampling procedure was followed in 25 private homes where samples of alveolar air were collected from 41 subjects who were not occupationally exposed and who acted as control group. All the samples were analysed by direct-injection gas-chromatography. PCE levels in dry-cleaners' homes proved to be significantly higher than in control houses (geometric means: 265 vs. 2 micrograms/m3, P < 0.001). PCE levels in the alveolar air exhaled by dry-cleaners, their family members and control subjects were statistically different (geometric means: 5140, 225 and 3 micrograms/m3, respectively; P < 0.001). PCE is a ubiquitous substance in indoor air, but is present at higher concentrations in apartments where dry-cleaners and their families live. Biological monitoring of PCE in alveolar air confirms that family members of dry-cleaners are more exposed than the general population.

Perchloroethylene exposure in 28 dry-cleaning establishments and in 25 homes occupied by dry cleaners in Modena, Italy, was investigated. Environmental air samples and alveolar air samples from dry cleaners (n = 60) and from their family members (n = 23) were collected. The degree of perchloroethylene on the dry-cleaning premises varied widely from establishment to establishment. Spot sampling ranged from 0.6 to 75 mg/m3, whereas sampling by personal passive dosimeters ranged from 2.6 to 221.5 mg/m3 (8-h time weighted average values). Perchloroethylene in alveolar air samples collected at the end of the work day correlated closely with the 8-h time weighted average values (r = .750, p = .001), and correlated also with alveolar air samples collected at home in the evening (r = .665, p = .001) and the following morning (r = .549, p < .001). Perchloroethylene levels inside the homes of dry cleaners appeared significantly higher than in 29 houses selected as controls (Mann Whitney U test, p < .001). Perchloroethylene in alveolar air samples collected at home suggests that nonoccupational exposure to perchloroethylene for family members of dry cleaners exists.

We evaluated colour vision in 35 dry-cleaners exposed to perchloroethylene (PCE) and in a paired number of controls matched for sex, age, alcohol consumption and cigarette smoking. A subclinical colour vision loss, mainly in the blue-yellow range, was present in dry-cleaners. This effect was related to PCE exposure levels, and appeared at environmental concentrations of the solvent well below the current exposure limits for exposed workers. The results suggest that PCE exposure, even at low environmental levels, can induce a dose-related impairment of colour vision.

Alveolar air samples were collected from 163 subjects at indoor swimming pools and from 77 nonexposed subjects. Chloroform was present in all samples collected from exposed subjects (median = 695.02 nmol/m3). It was found at very low levels in 53% of samples from nonexposed subjects. Alveolar air chloroform levels from people attending indoor swimming pools (mean value within each sampling session) were correlated with environmental air concentration (r = 0.907, p = .002). Analysis of variance showed that levels of chloroform in alveolar air depend on environmental air concentration, age, intensity of the sport activity, and kind of swimming. Chloroform levels in samples collected from competitive swimmers versus nonswimming visitors were different (F = 10.911, p = .001). Moreover, their pattern of swimming may affect chloroform concentration in alveolar air. The analysis of chloroform in alveolar air assesses indoor exposure in healthy subjects simply and at low cost.

This study evaluated swimmers and visitors who were exposed to chloroform (CHCl3) at three indoor swimming pools in Modena, Italy. Chloroform was measured in plasma samples of 127 subjects present at the pools and in 40 nonexposed subjects. The analyses were performed by head-space gas chromatography. Chloroform was present in all samples collected from the 127 subjects who attended the pools (median = 7.5 nmol/l; range = 0.8-25.1 nmol/l). Agonistic swimmers who trained for competitions showed a significantly higher mean value of plasma CHCl3 than nonagonistic swimmers and visitors. Plasma CHCl3 levels were significantly correlated with (a) CHCl3 concentrations in water and in environmental air, (b) the number of swimmers in the pools, and (c) the time spent swimming. Covariance analysis showed that plasma CHCl3 levels also depended on the intensity of the sport activity (total explained variance = 67.4%).

The Authors confirm the importance of fluoroprophylaxis in the prevention of Dental caries. They analyze the main methods of fluoroprophylaxis pointing out the systemic fluoroprophylaxis, effected by means of water fluoruration, as the best one for a valid prevention of dental caries on a large scale. In view of such a kind of fluoroprophylaxis in our country the Authors considered quite interesting to effect a research about the amount of fluoride in the waters of the district of Modena. The whole of results are reported.

The immunoenzymatic method for the research of specific IgM antibodies anti-Toxoplasma gondii is compared to the traditional methods of dosage: absorption of the IgG on staphylococcus and depolymerization of the IgM with 2-mercaptoethanol. The sensitivity and specificity of this method have been analyzed on a sample of 193 serums in order to consider the probabilities of false positive and negative reactions. The simplicity of method and the possibility of expressing values as reciprocal of the maximum dilution make this an elected method for the research of specific IgM. The reduced quantity of serum necessary in carrying out the test represents such a prerogative as to make this method particularly fit for researches on new-born babies.

Yersinia strains in surface waters and ground waters. After reviewing national and international writing regarding the prevalence of yersiniae in surface waters and ground waters, the Authors report data about a research carried out in the province of Modena (Italy). Over a period of 16 months (february 1986-may 1987) 89 water samples were examined (55 samples collected from rivers and streams and 34 from wells). During every sampling session two samples were collected; one was taken in a sterile bottle (1000 cm3), one by means of the Moore tampon, allowed to float in the stream for 48 h. Yersinia strains were isolated from 37% of the water samples; 33 samples gave a positive result. Forty one strains were isolated on the whole; filtration method by Millipore membrane appeared the most suitable technique in order to obtain a good recovery rate. Y. enterocolitica appeared the most represented species (43.8%), followed by Y. intermedia (21.9%) and Y. fredericksenii (17.1%). Five atypical strains were isolated, while no strain belonging to the species Y. kristensenii has been evidenced. No relevant difference in Yersinia presence appeared between surface waters and ground waters. No human pathogenic strain has been evidenced and all the isolates appeared belonging to environmental biogroups, serogroups and phage-types.

Exposure to chloroform (CHCl3) in indoor swimming pool swimmers. CHCl3 presence has been evidenced many times in water and air of indoor pools as a consequence of water chlorination with sodium hypochlorite or other chlorinated disinfectants. In previous studies CHCl3 in environmental air appeared at a high concentration within one meter over the surface of the water and was correlated to the number of swimmers inside the pool. CHCl3 has also been evidenced in blood serum samples of people present at the swimming pool, at different levels depending on: the concentration in the environmental air, the intensity and the length of the sport activity and the number of swimmers in the pool. At the end of the swimming session CHCl3 concentration tends to lower quickly and usually is no longer detectable within half an hour. Other studies have evidenced CHCl3 in breath samples (alveolar air) of a volunteer subject who swam one hour every day in an indoor pool in Modena. The spirometric parameters of the same subject were evaluated in order to estimate his CHCl3 uptake during time spent at the swimming pool, both resting and swimming in different modes. In the present paper the A.A. report data about CHCl3 exposure, intake and uptake bin five agonistic swimmers (three males and two females), members of the same sport association, and regularly attending the same indoor swimming pool in Modena. The five subjects have been examined during four different sessions. Within every session the samples were collected in five different moments according to the following scheme: 1) Hygiene Institute: samples of blood, alveolar air, environmental air. 2) Swimming pool, after 1 hour sitting near the pool edge: samples of alveolar air, environmental air (within 1 m on the water surface). 3) Swimming pool, after 1 hour swimming: samples of blood, alveolar air, environmental air (within 1 m on the water surface). 4) Hygiene Institute, 1 hour after the end of the swimming time: samples of alveolar air, environmental air. 5) Hygiene Institute, 30 min after the previous sampling: samples of alveolar air, environmental air. Spirometric parameters have been evaluated in every subject, after resting and swimming (point 2 and 3). CHCl3 uptake has been calculated using the following formula: U = V(CI--CA)t where: U = uptake (microgram/h) V = pulmonary ventilation (l/min) CI = inspired (environmental) concentration (microgram/m3) CA = alveolar concentration (microgram/m3) t = exposure time (min) CHCl3 levels after swimming always appeared quite high; however low levels were evidenced also before exposure (point 1).(ABSTRACT TRUNCATED AT 400 WORDS)

The indirect immunofluorescence assay for detecting anti-Toxoplasma gondii serum IgG is compared with the enzyme immunoassay employing a commercial kit for IgG. Enzyme immunoassay test shows a high degree of sensitivity, but it is less specific in comparison with indirect immunofluorescence test. There is evidence of direct relation between values expressed in Optical Density and reciprocal dilutions of sera; moreover a direct relation appears between Optical Density values and International Units/cm3. The authors claim that is advisable to give enzyme immunoassay test results, not only as Optical Density values, but also as antibody dilutions and International Units/cm3.

The authors compare enzyme immunoassay for rubella virus antibodies (ELISA) with a customary test, hemoagglutino-inhibition test. 392 sera samples were collected from healthy boys and girls; 304 girls had been vaccinated five years before. The authors research sensitivity and specificity of ELISA in comparison with hemoagglutino-inhibition test; ELISA proves to have a high degree of sensitivity, but it is less specific than hemoagglutino-inhibition test. This underlines the possibility to have false positive results from ELISA which appears a very useful test for epidemiological screenings, but less reliable for the diagnosis of recent rubella infections. As ELISA results are usually expressed in Optical Density values, and hemoagglutino-inhibition test results in antibodies dilutions, the authors have performed a graphic analysis; Optical Density values were evaluated in correspondence to the log2 of reciprocal dilutions of hemoagglutino-inhibition test positives. There is evidence of a linear correlation; in this way one can transform ELISA values in their correspondent antibodies dilutions, which are easily understood by general physicians.