P29 AICD IMPLANTATION IN A PATIENT RESURRECTED FROM CARDIAC ARREST, WITH THE R / T PHENOMENON AT THE HOLTER

A 72–year–old woman with hypertension for thirty years, resuscitated from cardiac arrest during prosthetic surgery of the right knee in January 2020, with external heart massage and orotracheal intubation. On examination Holter performed in February 2021, presence of couples and R / T phenomenon with Lown 1B–3–4A–5 class. The patient is subjected to coronary angiography which showed only mild atheroma without stenosis hemodynamically significant of the arterial districts explored. On the Echocardiogram, FE estimated at 60%. Based on the anamnestic data and the feedback from the fifth class of Lown at the Holter, it was decided to implant a dual chamber defibrillator for secondary prevention. The vulnerable point of refractory ventricular notoriously falls below 300 msec and in the clinical case in question there is a comparison to the holter of fifth class of lown with phenomenon R on T and coupling interval of 276 msec. The precocity of the ventricular ectopias is already in itself a risk factor for MI, reinforced in the case of clincio in question from a history of resuscitated cardiac arrest in a hospital setting. Not indicated to ours opinion of the electrophysiological inducibility study, given the positive clinical history and dynamic ECG according to Holter who examines the arrhythmic phenomenon in its spontaneous and natural way of presenting itself in circadian rhythm. The reproducibility in the laboratory with the SEI, of the electrical vulnerability was in fact in the recent years downsized, due to high specificity but low sensitivity, as there is in the clinical reality of patient neurovegetative and biohumoral fluxuonary factors, which favor the induction of malignant arrhythmias and that escape the predictive laboratory analysis. Making the patient safe with the implant of the bicameral AICD resulted from a clinical – diagnostic – instrumental analysis and after extensive discussion by the heart team in our Operating Unit.

P215 Effects of ARNI therapy on left atrial and ventricular longitudinal deformation and functional capacity in HFrEF patients

Background

valsartan and sacubitril combination (angiotensin receptor-neprilysin inhibitor, ARNI) was superior, in randomized trials, to lone ACE inhibitors in terms of reduction of cardiovascular mortality rate and hospitalization for acute heart (HF) in patients with HF with reduced ejection fraction (HFrEF). Purpose: the main goal of our study was to assess the effects of ARNI on left atrial (LA) and left (LV) and right ventricular (RV) function, evaluated by standard and speckle tracking echocardiography (STE), and on patients’ functional capacity by cardiopulmonary exercise testing (CPET), in patients with HFrEF. Methods: we prospectively enrolled 16 patients with a LV EF ≤35% and >18 years old, in two different centers with high expertise in HF management. Exclusion criteria included: symptomatic hypotension, stage IV renal failure (eGFR < 30 ml/min/1.73 m2), ACE-inhibitor (ACEi) intolerance or previous angioedema, poor acoustic window, refuse to participate to the study. At enrollment (T0), all patients were in therapy with ACEi or sartans (ARBs) and underwent physical examination, ECG, blood test (including NT-proBNP), standard echo, STE and CPET. We shifted therapy from ACEi/ARBs according to HF guidelines and we repeated all tests after 6 months. Results: population had an average age of 63 ± 9 years, 94% was males. Etiology was ischemic in one third of the subjects. At 6 months follow up, NT-proBNP was significantly lower (512.2 ± 518.5 vs 431.2 ± 330.1 ng/l, p 0,001) together with reduced LV filling pressure evaluated by E/A ratio and E/e’ ratio (11.2 ± 8.6 vs 8.8 ± 4.8, p 0.01). LV EF improved from 31.7 ± 3.4% to 36.2 ± 7.2% (p 0.01) and LV dimensions decreased. LV global longitudinal strain (GLS) did not change significantly while free wall RV GLS increased from – 20.4 ± 6.3% to – 24.6 ± 9%, p 0.001, as peak atrial longitudinal strain (PALS) did (16.1 ± 2.6% vs 27.6 ± 4.1%, p 0.001). Between CPET indexes, only VE/VCO2 slope improved but only with borderline statistical significance (32.7 ± 5.3 vs 29.7 ± 6.8, p 0.05, Fig. 1). Conclusions: this preliminary study evaluated for the first time the effects of ARNI on echocardiographic and CPET parameters at the same time. Our results could explain the favorable clinical benefits of ARNI therapy in HFrEF: improved biventricular function, lower LV filling pressure and a more efficient ventilatory response during effort.

Abstract P215 Figure. Fig.1

First Evidence of Cardiac Stem Cells From the Left Ventricular Apical Tip in Patients With Left Ventricular Assist Device Implantation

BACKGROUND

Recent studies have challenged the dogma that the adult heart is a postmitotic organ and raise the possibility of the existence of resident cardiac stem cells (CSCs). Our study aimed to explore if these CSCs are present in the "ventricular tip" obtained during left ventricular assist device (LVAD) implantation from patients with end-stage heart failure (HF) and the relationship with LV dysfunctional area extent.

METHODS

Four consecutive patients with ischemic cardiomyopathy and end-stage HF submitted to LVAD implantation were studied. The explanted "ventricular tip" was used as a sample of apical myocardial tissue for the pathological examination. Patients underwent clinical and echocardiographic examination, both standard transthoracic echocardiography (TTE) and speckle tracking echocardiography (STE), before LVAD implantation.

RESULTS

All patients presented severe apical dysfunction, with apical akinesis/diskinesis and very low levels of apical longitudinal strain (-3.5 ± 2.9%). Despite this, the presence of CSCs was demonstrated in pathological myocardial samples of "ventricular tip" in all 4 of the patients. It was found to be a mean of 6 c-kit cells in 10 fields magnification 40×.

CONCLUSIONS

Cardiac stem cells can be identified in the LV apical segment of patients who have undergone LVAD implantation despite LV apical fibrosis.

[Measurement of real personal noise attenuation using earplugs with the E-A-Rfit system]

BACKGROUND

The assessment of efficiency of hearing protection devices (HPDs), conducted above statutory limits, must be made using a standardized method while devices are worn; however, standardized and suitable laboratory conditions are difficult to encounter at the workplace. To overcome this problem, there are methods of measurement at the workplace such as "field-microphone-in-real-ear" (F-MIRE).

OBJECTIVES

The study was concerned with the measurement of real noise attenuation using earplugs and a new evaluation system: we checked the difference between "real" attenuation (at workplace) and "theorical" attenuation (reproduced in the laboratory) as stated by the manufacturer.

METHODS

We used the E-A-Rfit computerized method, which measures the loss of attenuation of earplugs in the ear, calculating the difference of sound pressure between an "outside" microphone and an "inside" one, in relation to the same earplug. The measurements at the workplace were carried out on eight subjects with good hearing levels (aged between 20 and 25 years), who were trained to wear the devices correctly. After the tests carried out with the E-A-Rfit system, which does not require a subjective answer, we obtained graphs and tables showing real noise attenuation.

RESULTS/CONCLUSIONS

We propose a comparison between hearing threshold for frequency, personal attenuation rating (PAR) and single number rating (SNR, provided by manufacturer): a difference of 10 dB (PAR 27 db vs. SNR 37 dB) was clearly evident although dissimilar methods were used to obtain such values. The instrument is rapid, simple and objective to use and also allows personalized information and training for every worker.

[Exposure to asbestos in buildings in areas of Basilicata characterized by the presence of rocks containing tremolite]

Lucania, in southern Italy, is characterized by areas with natural outcrops of rocks containing tremolite. The study aims to assess the risk of exposure to asbestos in the building workers in these areas through environmental sampling near sites for implementation of safety of roads built on serpentinite rocks and personal sampling in a group of persons who work in the building industry and a group of residents engaged in activities without contact with the ground. Near road sites was found the presence of airborne tremolite in 66% of environmental samples with peaks up to 31 ff/l. The analysis of personal samples showed the presence of tremolite in doses higher than the natural background in 100% of the building workers, while there were no fibers in the samples of residents employed in activities without soil disturbance. The study shows that the building in areas with naturally occurring asbestos determines a condition of significant occupational exposure to asbestos. Adequate safety measures for workers exposed are needed.

[Asbestos and agriculture: new perspectives of risk]

The presence of ophiolites in areas of Basilicata, where there have been reports of mesothelioma in farmers, is known. This study evaluates the increased risk of exposure to tremolite in carrying out agricultural activities. Cases of mesothelioma occurred in farmers with unknown exposure to asbestos have been selected and assessed the employment in areas contaminated by tremolite. Personal samplings were conducted in a group of farmers employed in these areas and a group of subjects used in activities that do not involve contact with the ground. For the 5% of cases of mesothelioma in the lucan register emerged exposure to asbestos exclusively in farming activities in areas at tremolite risk. The analysis of the samples showed the presence of personal fibers of tremolite in 2/3 of the cases. In 60% there was an overcoming of the natural limit of 2 ff/l, with a peak up to 23.6 ff/l. The study shows that the risk of exposure to tremolite in agriculture is significantly higher than natural exposure.

[And yet there is a risk--do it yourself]

Our study has examined the valuation of exposure to dust, noise and hand-arm vibrations (HAVs) during "extra-professional" activities of do-it-yourself, like wood smoothing, considering a group of 8 heterogeneous volunteer subjects (not expert of the sector), to find any kind of variability among the subjects. The results have shown a moderate risk for dust exposure and a realer one for HAVs, also higher noise exposure levels when an aspiration system is added to the sander. It's important that the exposure time considered in this study is not comparable to professional time exposure, cause of the "domestic" feature of this activities. Moreover, data could be influenced by different use conditions, grip and material grounds. It's also significant that there are not controls, formation and information of the subjects about the health risks, as well as ipersusceptibility.

[Temporary hearing threshold shift in policemen after firearm training]

BACKGROUND

The paper involves exposure to noise of the State Police officers connected with the use of firearms. The noise generated by these weapons is of short duration and high intensity.

METHODS

The research was carried out during the sessions of firearm training of State Police officers to assess exposure to noise.

RESULTS

The values of the various investigations, both audiometric and phonometric, carried out made it possible to demonstrate a significant exposure and a temporary increase in the threshold, above the frequency of 6000 Hz.

CONCLUSION

Even taking account of the abatement from use of headphones, an exposure was demonstrated that was above the statutory limits, as was confirmed by the temporary hearing threshold shift.

[Exposure to air pollutants in the city of Bari]

BACKGROUND

Air pollution leads to increased levels of morbidity and mortality for cardiovascular and respiratory diseases in populations living in urban environments.

OBJECTIVES

Our study tested the possibility of using sampling techniques that are typical of industrial hygiene to measure exposure to atmospheric pollutants and using personal samplers for concentrations of certain pollutants to which an ordinary resident of Bari is exposed on a daily basis.

METHODS

We monitored dusts (PM10, PM2.5), CO, CO2, humidity, ventilation and noise, by dynamical sampling along a route on foot, bicycle, motorbike and automobile and then compared the results with data provided by fixed stations distributed in the municipality of Bari.

RESULTS

By comparing our data with those values provided for by the law, we found out that the concentrations of all pollutants resulted to be higher than 50 microg/m3, with the exception of the measurements carried out along the route by car. The measurements of PM2.5 were, on average, similar to the values of PM10 for the route on foot, but they were totally different for the measurements made along the route by car, bicycle and motorbike. Moreover, comparing our data with those obtained from the municipal network of fixed stations, we found that results provided by our measurements were higher for PM10.

CONCLUSIONS

Considering that compliance with the limits set by law refers to average values over 24 hours, we can conclude that those hours in which pollutant concentration reaches a risk level shall be considered especially regarding groups of people with respiratory disorders.

Effect of lead on the levels of some immunoregulatory cytokines in occupationally exposed workers

Lead (Pb) may affect humoral and cellular immunity, acting on lymphocytes as well as on granulocytes and monocytes. Cytokines and nitric oxide (NO) play a central role in the immune balance. In this study, plasma levels of nitrites and nitrates (NOx), IL2, IL4, IL6, IL10, TNF-alpha and INF-gamma, were measured in healthy workers with very low (Pb-B=3.2-18.0 microg/dL) and low (Pb-B=9.1-46.0 microg/dL) Pb-exposure compared to non-exposed workers. Low Pb-exposed workers (Pb-B=9.1 -46.0 microg/ dL) were found to have significantly higher plasma IL-10 levels, and tendentially higher plasma TNF-alpha levels compared to non-exposed workers. This is the first report of a significant increase of plasma IL-10 levels in Pb-exposed workers. Plasma IL-10 increase was influenced by blood Pb levels even after correction for main confounding factors. No difference was found in plasma NOx levels between Pb-exposed and non-exposed workers, which is in agreement with previous findings exclusively regarding groups in the general population. Low Pb-exposure can induce an increase of pro-inflammatory cytokines, such as TNF-alpha, with a consequent increase of other cytokines, such as IL-10, considered a T cell cross-regulatory factor, suggesting possible interference of Pb in the system of immunophlogosis.

No-occupational exposure to noise

The aim of the research was to evaluate the risk for the health of the disco-goers related to no-professional exposition to noise produced by speakers of discos. The noise has been measured in the middle of a disco using a class 1 phonometer. The exposition level was calculated using the formula quoted in the D.Lgs 277/91 (Italian legislative decree) and the possible damage was calculated using the Casini's formula. The calculated daily exposition level was 99,1 dBA and the weekly exposition was 92.1 dBA. The results indicate that the hypacusia damage due to these expositions can be considered almost sure.

[Report on the activities carried out in the research project of the Ministry of Instruction, University, and Research entitled "Environmental and occupational exposure to inorganic lead: assessment of toxic effects of current doses and related preventive measures"]

It is here presented the project sustained by the Ministry of Public Instruction, University and Research "Environmental and Occupational Exposure to Inorganic Lead: assessment of human health effects due to current doses and preventive measures" ruled out between 2001 and 2003. The aim of the study was to investigate about the toxic effects related to current occupational exposures to inorganic lead (particularly those effects concerning blood pressure, carcinogenic risk, nervous and immunological systems), to identify hypersusceptibility conditions, particularly the ALAD genetic polymorphism and to evaluate the role of traditional biomarker and the possibility of introducing new ones. In the present article the procedures followed during the project lasting and the contribution of each Unit are described. The results of the research, presented in detail in the current issue, do confirm the inadequacy of the biological exposure index nowadays ruled by Lex 25/2002.

[Anemia in workers exposed to lead: update on differential diagnosis]

Occupational lead exposure can cause anemia at blood lead levels >50 microg/dl, as high as rarely occurs in industrialized countries nowadays. Whereas other forms of anemia are fairly probable to be found in lead exposed workers, especially in areas highly endemicfor extraoccupational anemias, such as beta thalassemia and iron deficiency anemia. The etiology of anemias has to be correctly defined in order to assess suitable therapeutical approaches and medicolegal consequences. The objective of this study is to verify in male lead exposed workers whether an accurate evaluation of hemocromocytometric parameters and of usual biological indices of lead exposure and effect on heme can differentiate the most common forms of anemia in Southern Italy. 68 workers occupationally exposed to low to moderate lead doses were studied and 59 workers of an alimentary plant have been taken as control group. On venous blood samples collected from these workers a complete hemocromocytometric test was performed and blood lead and erythrocytic zincoprotoporphyrin were determined. Anemia (Hb <l3 g/dl) was detected in six lead exposed workers and in a nonexposed worker. The reasoned evaluation of laboratory parameters led to identify among lead exposed workers four subjects with high probability of beta-thalassemic trait and two with lead poisoning anemia. Moreover a diagnostic algorithm was developed based on literature that seems to be able to discriminate lead poisoning from other causes of anemia in lead exposed workers in this study.

[Reduced thymulin production during occupational exposure to lead]

Thymulin is a thymic hormone that being activated by binding a zinc ion promotes differentiation and several functions of T lymphocytes. It has been demonstrated only in experimental animals that metallic lead (Pb) is able to cause adverse effects on thymocyte number and function. The objective of this study is to evaluate the plasmatic level of active thymulin of 58 male workers being exposed for more than one year to low lead doses with respect to 59 male never exposed workers. All these were subjected to anamnesis collection, medical examination and determination of blood lead (PbB), plasmatic lead (PbPl), plasmatic thymulin, urinary lead (PbU) and urinary zinc (ZnU) levels. The mean plasma concentration of active thymulin was significantly lower in lead exposed than in non exposed workers. Active thymulin was also significantly and negatively correlated to PbB, PbPl and PbU level and resulted to be significantly and negatively influenced by PbB. Lead exposed workers had slightly higher zinc concentration in urine than non exposed workers, increasing ZnU levels by class of PbB. It is the first time that a toxic effect of lead on plasmatic active thymulin levels is demonstrated in humans, particularly in occupationally exposed workers. This study opens perspectives for further research that would both confirm the results and verify the mechanisms of action of lead on thymulin either direct or indirect and the possible role of zinc.

[Assessment of neurobehavioral functions of workers exposed to low doses of metallic lead]

The effects of low-dose lead occupational exposure on neurobehavioral functions are still not well defined by international literature. The objective of this study is to assess by psychometric testing the presence of possible neuropsychological impairment in a group of male Italian workers with low blood lead levels in comparison to an adequate non exposed worker group. Given informed consent to take part to the study, all workers were interviewed about their working and clinical history and underwent determination of blood lead levels (PbB). An internationally validated computerized battery of psychometric tests and a standardized paper-and-pencil version of mood self-rating scale and WAIS-R Vocabulary subtest were also administered to the workers. Exposed workers had a geometric mean of PbB significantly higher than non exposed workers, but rather low (16.4 +/- 1.7 microg/dl). The results of psychometric tests were not significantly different between the two worker groups, even after adjusting for the main confounding factors. In workers exposed to low lead doses no neurobehavioral abnormalities were demonstrated by the administered psychometric test battery.

[ALAD polymorphism and indicators of dose and effects of occupational exposure to inorganic lead]

The delta-aminolevulinate dehydrase (ALAD) genetic polymorphism was investigated along with biomarkers of lead exposure and effect on 333 male workers, occupationally exposed to lead, with blood lead levels (PbB) higher than 100 microg/l. ALAD genotype frequencies were distributed as expected among Caucasians. Workers bearing at least one ALAD-2 allele showed PbB values slightly higher than those from ALAD-1-1 subjects, who also exhibited higher urinary delta-aminolevulinic acid (ALAU) and blood zinc protoporphyrin (ZPP) levels. The plasmatic lead (PbP)/PbB ratio was similar in both groups. Exposure and effect biomarkers were significantly each other correlated among ALAD-1-1 subjects only, who showed also a significant inverse relationship between ALAD activity and ZPP values. Results confirm previous studies, supporting the hypothesis that ALAD polymorphism may interfere with toxico-kinetic and toxico-dynamic parameters of occupational exposure to Pb.

[Exposure to PAHs, urinary 1-pyrenol and DNA adducts in samples from a population living at different distances from a steel plant]

This study aims at measuring association between environmental exposure to PAHs and internal or biologically effective dose biomarkers among 212 individuals living at different distance from the industrial area of Taranto, Italy. Environmental PAH exposure was determined by area monitoring. PAH levels was measured by HPLC UV/FL. Urinary 1-hydroxypyrene levels were measured by HPLC/Fluorescence. The levels of DNA adducts were determined by 32P. post-labelling. A questionnaire was administered to gather personal data, residence, occupational history, alcohol, tobacco smoke, and diet, to control for other sources of exposure to PAH. Blood and urinary samples, drawn from the subjects studied were collected and analysed. A multivariate regression model was used to investigate the influence of several confounding factors. Housing was placed within 1 km from smokestacks in Taranto and Statte, whereas they were more far away in Locorotondo and in Alberobello. The prevalence of current smokers was 31.6%.

[Increase of TNF-alpha in subjects occupationally exposed to lead]

Occupational exposure at low doses of lead induces a significant increase of TNF-alpha plasma levels. Recently has been showed the crucial role on atherosclerosis origin of this pro-inflammatory cytokine. It is assumable a contribution of lead in atherosclerosis course in exposed subjects.

[Effects on arterial pressure of exposure to low doses of inorganic lead: preliminary results]

The aim of this study is to evaluate the effects of occupational exposure to low inorganic lead (Pb) doses on blood pressure of exposed (E) workers. 44 workers of a foundry of lead wrecks and 14 workers employed in enameling and decoration of a manufacturing firm of artistic ceramics were examined. The group of non-exposed (NE) subjects is formed by 59 workers of packaging unit of a food industry. A questionnaire has been administered to all the workers on general characteristics and life habits. Systolic and diastolic blood pressure were also measured and venous blood collection performed for the determination of blood lead levels. Mean blood lead levels (PbB) and mean diastolic blood pressure (DBP) resulted significantly higher in the group of exposed workers of the foundry. Stratifing exposed workers with respect to the median of PbB (18 micrograms/dl), workers with PbB > 18 micrograms/dl presented a mean DBP significantly higher than exposed with PbB < or = 18 micrograms/dl and non-exposed subjects. PbB takes part significantly in determination of DBP, also considering main confounding factors as age, BMI, pack-years and alcohol consumption.

[Occupational exposure to inhalation anesthetics: 10 years of measurements at hospitals in Puglia]

The Authors provide the data gathered from measurements of nitrous oxide in the operating room of Puglia during the period between 1993 and 2003. They prove significant reductions of pollution according with time and they verify lower pollution levels in the operating rooms of private hospitals with respect to public facilities. The importance of the maintenance of gas distribution and evacuation systems is shown and a method of environmental and biological monitoring is provided. Finally, the Authors prove the utility of the graphic representation of the measurements, conduced utilising dedicated instrumentation.

[Dose-response curve in the study of the effects of exposure to crystalline silica]

The cumulative exposure to crystalline silica (SiO2) implies a linear relation between duration of exposure and SiO2 concentration, not always suitable to working situations of the last decades. A more correct definition of dose-response curve has currently to consider also different characteristics of SiO2, specifically: possible short-term increases in environmental SiO2 concentration, different mineralogical and surface properties of natural silica polymorphs, age of SiO2 particles, presence of contaminants on the surface of silica particles or even in the respirable fraction of total dust, respirable dust concentration in which SiO2 is diluted and other conditions, also affecting the host, able to slow alveolar clearance and lengthen permanence time of particles in the lung. Many models of definition of cumulative exposure so conceived have been proposed. However, to define the occupational risk threshold to contract silicosis and other silica-related diseases a number of models of cumulative exposure, i.e. biologically effective dose of SiO2, are likely to be delineated that take into account only factors specifically present in different occupational situations.

[Non-occupational exposure to noise]

The authors report the data related to the measures effected in some environments where leisure time activities are developed. In the light of the elevated values, the authors have effected the calculation of the Lep,d as laid down by D.Lgs 277/91 to verify the existence of conditions of risk that result verified.

Sister chromatid exchange (SCE) and micronucleus (MN) frequencies in lymphocytes of gasoline station attendants

Peripheral blood lymphocytes from 22 men with low average exposure (229 micrograms/m3 = 0.72 ppm) to benzene and 19 control men were investigated for Sister Chromatid Exchange (SCE) frequency. The majority of the men (21 exposed, 19 controls) were also investigated using the micronucleus assay (MN). The exposed subjects were employed at 10 different gas stations in or near the city (Bari/South Italy). SCE frequencies were significantly related with age and smoking habits, on the contrary no relation was observed between SCE and length of employment (SCE = 7.41 + 0.03.age (*) + 0.0001.length of employment (n.s.) + 0.03.cigarette consumption (*); F = 4.87; p < 0.01; (*) significant; (n.s.) non-significant). MN frequencies were significantly increased in relation with length of employment; but no relation was observed when age and smoking habits were taken into consideration (regression model: MN = 18.03 + 0.006.age (n.s.) + 0.32.length of employment (*) - 0.1.cigarette consumption (n.s.); F = 4.138; p < 0.05).

[Benzene pollution in the city of Bari]

The Authors reported data of benzene concentrations obtained in Bari during period of time between 1990 and 1995; the measured levels of benzene concentrations are not in accord with referent values prescribed by the law, mostly always they are exceeded. Present study also discuss problems related to gasoline consumption and the number of cars in circulation.

Auditory dysfunction in occupational noise exposed workers

Occupational noise-induced hearing loss (NIHL) is well known to be an epidemiologically relevant problem. The subjects affected with NIHL show alteration of hearing thresholds as well as a worsening of the cochlear analysis functions and, usually, an impaired speech discrimination in presence of background noise. The study has evaluated the relationships between hearing threshold and equivalent exposure lever per day (Lepd), age and working seniority in a homogeneous sample of occupationally noise exposed workers. Three subgroups were also selected to study the most important cochlear functions as well as nerve and central functions. The first subgroup (Nn) contained normal hearing workers exposed to non-hazardous noise, while the second (Bn) contained workers exposed to high level continuous noise during their work day without clinical evidence of NIHL. The third subgroup (Bd) included subjects affected with the typical 4 kHz notch exposed to the same noise conditions than subgroup Bn. The results show that the hearing impaired subjects have the worst overall cochlear performance; however also the normal hearing workers exposed to hazardous noise have worse performance than subgroup Nn, relatively to high frequency thresholds, frequency resolution, TEOAEs, DPOAEs, stapedial acoustic reflex dynamic parameters. The results suggest that these measures could be used in the monitoring of the NIHL as indicators of subtle alterations of the hearing function.

[The toxicology and prevention of the risks of occupational exposure to aromatic polycyclic hydrocarbons. I. Guide lines for the prevention of the risks of occupational exposure to aromatic polycyclic hydrocarbons. Società Italiana Valori di Riferimento and Cattedra di Medicina del Lavoro, Università di Brescia]

These guidelines mainly deal with prevention of carcinogenic effects following occupational exposure to polycyclic aromatic hydrocarbons (PAH). After some toxicological remarks, the guidelines define a possible method to demonstrate and evaluate occupational exposure to PAH. In particular, it is illustrated the strategy of environmental monitoring and indicated which PAH should be measured, with suggestion about the most appropriate analytical techniques. As regards biological monitoring, the 1-OH-pyreneseems to be currently the most useful indicator since it reflects the recent and global exposure to PAH. The guidelines also give elements to interpret monitoring data, taking into account environmental and biological reference and limit values suggested by some authors, Associations, or current regulations. The most important health effects are carcinogenic and excess risks have been described mainly for lung, bladder and skin cancer in some PAH exposed workers. The studies on cytogenetic effects showed contradictory results. On the basis of such information and current regulations, the guidelines show how to perform health surveillance in preventive and periodical examinations and how to proceed for the information and formation of exposed workers. It is not advisable, on the basis of the current scientific data, to screen asymptomatic PAH exposed workers for early diagnosis of lung or bladder cancer, nor it is opportune the use of tumor markers for health surveillance nor is genetic screening applicable for individual susceptibility evaluation outside research programs.

[The toxicology and prevention of the risks of occupational exposure to aromatic polycyclic hydrocarbons. II. Toxicology. Exposure assessment. Environmental and biological monitoring]

The evaluation of exposure to polycyclic aromatic hydrocarbons (PAH) should firstly comply with current regulations (D.Lgs. 626/94), that is, identify the compounds and exposed subjects, quantify exposure, adopt preventive measures and health and epidemiological surveillance. Environmental monitoring should take into account the technological cycle and the tasks with higher PAH exposure risk, and the main sources of emissions. In the case of skin contamination, it should be considered the measure of skin PAH by means of sampling or removal techniques; moreover, the determination of urinary hydroxypyrene (1-HP) should be performed. It is mandatory to analyse (Benz[a]) anthracene; Benzo[b]fluroanthene; Benzo[j]fluoranthene; Benzo[k]fluoranthene; Benzo[a]pyrene; Dibenzo[a,h]anthracene, i.e. the PAH marked with the R45-R49 phrase. When 1-HP determination is planned, Pyrene should be added. Biological monitoring has been addressed mainly to hydroxylated metabolites of pyrene and among these 1-HP, the main metabolite of pyrene, although non occupational factors, such as tobacco smoking and consumption of smoked foods are potentially confounding. Urinary mutagenicity tests which are heavily influenced by non occupational factors such as tobacco smoking and diet are not advisable. The determination of DNA and protein adducts is a promising test for evaluation of metabolic active dose but at the moment it is not suitable for routine use in occupational medicine. In order to interpret environmental and biological data, it will be useful to consider appropriate reference values ("limit" "guide", "operative", "maximum admissible") such as 0.1 mg/m3 for total PAH extracted with benzene, 5 micrograms/m3 for the mixture of 15 PAH listed by US NTP, the limits varying from 0.1 to 5 micrograms/m3 for Benzo[a]pyrene, and 2.7-4.4 micrograms/g creat, for 1-HP.

[Mucociliary clearance and respiratory function in foundry workers]

The aim of the study was to establish whether changes occur in respiratory function, particularly mucociliary clearance, among second fusion smeltery workers. The research covered 93 male smelters employed in steel forming and casting and 116 male workers of an electric power station, considered as non-exposed. Physiological, pathological and occupational histories of all subjects under study were available. An ECCS respiratory symptoms questionnaire was administered to all subjects ad the two groups also underwent a general medical examination, a spirometry and a chest X-ray. During the medical examination sputum was collected from the subjects to measure mucus transport rate on frog palate, expressed as Normalised Frog Palate Transport Rate (NFPTR). For the environmental research, dust, fumes and gas samplings were taken either at a fixed station or by means of personal dosimeters. Environmental research revealed very low concentrations of respiratory irritants (total dust: 0.2-6.8 mg/m3; respirable dust: 0.1-4.9 mg/m3; total silica: < 2-15.5%; respirable silica: < 0.004-0.3 mg/m3; iron: 0.008-0.085 mg/m3; chromium and manganese: < 0.001 mg/m3; fumes and gases: well below the TLV. The two groups were homogeneous with regard to age and smoking habits. Exposed workers showed rales, dyspnoea and spontaneous phlegm more frequently than non-exposed workers. NFPTR alterations were checked in 49 out of 81 exposed and in 18 out of 81 non-exposed subjects (chi squared = 22.9; p < 0.001). Stratification of the results according to smoking habits further confirmed the strong association between occupational exposure and NFPTR alterations. Smelters showed significantly lower mean NFPTR values compared to non-exposed subjects; also, the mean value of NFPTR in the exposed was below 0.70, which is considered the lowest individual limit in normal subjects. The only variable which explains a large part of the variability of NFPTR is past work in a smeltery rather than in an electric power station. The spirometries showed that only the mean PEF values were significantly lower among the exposed. Stratified analysis of the results according to smoking habits in the two groups revealed a close association between smeltery work and reduction of PEF to under 80% of the ECCS 1983 theoretical values, independently of smoking habits. We also compared the mean PEF values, both as measured values and as percent values of the ECCS 1983 theoretical values, stratified for occupational exposure and smoking; the results again showed that differences between these mean values were mainly due to current or past work in the foundry.(ABSTRACT TRUNCATED AT 400 WORDS)

[The inhalation of low concentrations of manganese powders produces changes in respiratory mucociliary clearance]

The aim of this study is to verify whether inhaling metallic dusts, containing a lower concentration of Mn (as Mn3O4) than current TLV can cause alterations in exposed workers tracheobronchial mucociliary clearance. We studied 20 grinders using an 11.5-13% Mn steel, and a control group of 21 standard steel grinders, employed in the same foundry. Environmental Mn dust was measured by personal samplers. All workers were administered a questionnaire about chronic bronchitis; the following examinations were also carried out: medical examination, spirometry, chest standard X-ray and urinary Mn dosage. Mucociliary clearance was measured by human respiratory mucus transportability on frog palate and expressed as normalized frog palate transport rate (NFPTR). Mucus was obtained through a sputum so protected as to avoid salivary contamination. Environmental measurements showed a Mn concentration from 0.1 to 1 mg/m3 with respect to a TLV of 5 mg/m3. Exposed workers and control group were homogeneous as far as age, working period, tobacco smoking habit and spirometric parameters are concerned. Chest X-ray examination showed no evidence of pneumoconiosis. Mn exposed workers showed a NFPTR reduction, if compared to normal level (0.70). NFPTR average value in exposed group has come out to be much lower than in control group. NFPTR alteration in Mn exposed group appears to be strictly linked to a longer than 15 years working seniority. Urinary Mn values resulted extremely low in each worker and their average was not significantly different between the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood lead and erythrocyte protoporphyrin levels in the general population of an area in southern Italy

Seven hundred and twenty subjects not occupationally exposed to lead were examined, among blood donors from a Bari hospital. Short case-histories were taken including personal data, residence, occupation, habits. The parameters considered were blood lead and protoporphyrin levels. The mean values found in Bari were respectively, 8.4 micrograms/100 ml, S.D. = 4.5 and 11.3 micrograms/100 ml, S.D. = 10.9. The results show that, at present, reference values for blood lead levels in the population are lower than the limits set by D.P.R. No. 496/82 which incorporates EEC directive No. 77/312 concerning biological monitoring of lead exposed populations.

[The phagocytic activity of the neutrophilic granulocytes via chemoluminescence and occupational exposure to lead]

The lead interference on the immunological activity is the aim of this survey. Therefore, it was examined the phagocytic function of the PMN cells on a group of 20 subjects occupationally exposed to the toxic and on 20 other assigned to the control group using the chemoluminescent assay. In both groups it was determined the biologicals parameters of exposure to the toxic. It was evident a statistically significant decrease of the average values in the exposed group compared to the control group, even if it wasn't directly correlated with the exposure biological indicators.

[Therapy and iron supplements with ferritin iron during pregnancy. Randomized prospective study of 458 cases]

A randomized polycentric study was programmed to establish the effects of daily administration of ferritin iron from early pregnancy to puerperium. 254 women with normal iron balance at the beginning of their pregnancy were randomized receiving no supplements or 40 mg iron daily. At the end of pregnancy iron balance was still normal only in one third of the pregnant women of the first group versus two third of the second group. 204 women who were iron-deficient received daily 40 or 120 mg of iron; in this group anemia developed less frequently (13% versus 29%) and iron balance normalized in one subject on four; the great majority of these women remained iron-deficient. Unwanted effects of minimal or mild relevance, and almost always sporadic were observed in 6.5% of cases and with the reduction or withdraw of the treatment in only 1.4% of cases. These results showed that daily administration of ferritin iron during pregnancy is effective and well tolerated; furthermore they suggest that the treatment must be done with at least 60 mg daily in women with normal iron balance and protracted also after the puerperium in iron deficient subjects.

[Evaluation of noise-induced injury: consideration of a group of exposed cement workers]

The study covered 1334 workers employed in 12 cement factories located in southern Italy. They were submitted to audiometric screening consisting of a questionnaire containing questions on past otologic complaints, metabolic diseases, use of ototoxic drugs and past occupational or non-occupational exposure to noise, plus otoscopic examination and full audiometric examination. The results revealed a statistically significant relationship between duration of exposure to noise and elevation in the hearing threshold. The highest noise levels were found in the "crude/baked mills" department; however, the highest frequency of occupational hearing loss was observed in the "mine and crushing installations", maintenance and "hodmen" departments. On the question of assessment of the audiometric tracings for preventive and insurance purposes, attention is drawn to the fact that there is a need for a method that will enable an evaluation for prevention to be transformed into an evaluation for insurance. This method should in any case allow for deduction of the portion of hearing loss regarding presbycusis and socioacusis and take due account of the 3 KHz frequency. The attention of industry and public administration is drawn to the urgent need for prevention programs to protect against noise-induced hearing loss in both occupational and non-occupational settings.

[Ionizing radiation and video computer terminals]

VDTs are more frequently being used and, therefore have given rise to the problem of security among operators exposed to possible X-ray emissions. The authors report the results of a dosimetric investigation, carried out through TLD CaF2:Dy on X-ray exposure levels close to video display terminals of a data processing center. After testing the exposure percentage values and the measurements adjusted to one-year basis, the authors report that the value are generally similar to those existing in the environment even though significant values have been found in a few cases.