Biological monitoring of exposure to polycyclic aromatic hydrocarbons and to metallic elements in Italian Navy workers operating near the industrial area in Taranto (South Italy).

OBJECTIVES: To assess, by means of biological monitoring, exposure to polycyclic aromatic hydrocarbons (PAHs) and to metallic elements in Italian Navy workers operating near the industrial area in Taranto, and thereby estimate the health risk. METHODS: A total of 450 workers in the Italian Navy were examined; they had office type jobs, and 150 of them worked near the industrial area in Taranto (exposed group), 150 in Taranto but far from this area (internal control group) and 150 in Brindisi (external control group). The recruited workers were administered a questionnaire inquiring about current and previous working activities, personal medical history, lifestyle and dietary habits, and their residence location. Then they collected a urine sample for the determination of 1-hydroxypyrene, 2-naphthol, cotinine and the metallic elements As, Cd, Co, Cr, Mn, Ni, Pb, Cu, Zn and Hg. The latter were measured in 110 workers in each group. In addition, in some of the work sites of the three groups, environmental samplings were carried out to determine PAHs and the 10 metallic elements, also taking into account the wind direction. RESULTS: Airborne benzo(a)pyrene concentrations at the different sampling sites ranged from 0.02 to 0.06 ng/m3 and naphthalene between <25 and 65.3 ng/m3, regardless of the wind direction. Among the metallic elements, As, Cd, Co, Cr, Hg, Pb, Cu and Zn were present at concentrations below or just above the limit of detection (LOD). Mn and Ni were slightly higher in the work sites of the exposed group. The urinary concentrations of 1-hydroxypyrene, 2-naphthol and the single metallic elements were not higher in the exposed workers group than in the other 2 groups. Smokers had significantly higher urinary 1-hydroxypyrene and 2-naphthol concentrations, whereas cigarette smoking did not condition a higher urinary elimination of metallic elements in the three groups with the exception of Cd and Pb. Moreover, residence location conditioned Mn, Hg and As urinary excretion, consumption of shellfish and/or crustaceans in the 72 hours before urine collection conditioned As elimination, and consumption of legumes in the 72 hours before urine collection conditioned Ni elimination. CONCLUSIONS: This research did not find a higher urinary excretion of 1-hydroxypyrene, 2-naphthol and As, Cd, Co, Cr, Mn, Ni, Pb, Cu, Zn and Hg in the exposed workers group as compared to the internal control group working far from the industrial area of Taranto, nor in the group working in another city far away from Taranto, Brindisi. Therefore, it indicated that workers in the Italian Navy operating near the industrial area in Taranto were not exposed to a greater risk attributable to exposure to PAHs and metallic elements than the two control groups.

Tetanus-diphtheria vaccination in adults: the long-term persistence of antibodies is not dependent on polyclonal B-cell activation and the defective response to diphtheria toxoid re-vaccination is associated to HLADRB1∗01.

Cellular and humoral immune responses to tetanus-diphtheria vaccine (Td) were assessed in human leukocyte antigen (HLA)-typed Italian military personnel who received multiple concomitant vaccines. Td-specific antibodies and T-lymphocytes were measured in individuals with one (group-1) and more than one (group-2) Td boosters. A third group (group-3), who received several vaccines, but not Td, was studied to verify the hypothesis of the polyclonal B-cell activation as mechanism for antibody persistence. The antibody response to Td toxoids was higher in group-1, who showed lower baseline antibody levels, than in group-2 subjects. The antibody response to tetanus was higher than to diphtheria toxoid in both groups. No correlation between antibody and cellular response, and no interference in the response to Td by co-administration of different vaccines were observed. HLA-DRB1∗01 allele was detected at significant higher frequency in subjects unable to double the baseline anti-diphtheria antibody levels after the vaccination. Anti-tetanus and diphtheria antibodies half-lives were assessed and the long-lasting persistence above the threshold for protection (0.1 IU/ml) was estimated in over 65 and 20 years, respectively. No significant increase of anti-diphtheria antibodies was observed in consequence of polyclonal B-cell activation. This study emphasizes the duration of Td vaccination-induced seroprotection, suggesting that re-vaccination should probably be performed at intervals longer than 10 years. No reciprocal interference by concomitantly administered vaccines has been observed. HLA-DRB1∗01 allele was significantly associated with anti-diphtheria defective response. Finally, this study does not confirm that anti-diphtheria antibody levels are maintained by polyclonal B-cell activation. Clinical trial registry: The study was registered with NCT01807780.

Lack of evidence for post-vaccine onset of autoimmune/lymphoproliferative disorders, during a nine-month follow-up in multiply vaccinated Italian military personnel.

Anecdotal case reports, amplified by mass media and internet-based opinion groups, have recently indicated vaccinations as possibly responsible for autoimmunity/lymphoproliferation development. Multiply vaccinated Italian military personnel (group 1, operating in Italy, group 2, operating in Lebanon) were followed-up for nine months to monitor possible post-vaccine autoimmunity/lymphoproliferation onset. No serious adverse event was noticed in both groups. Multivariate analysis of intergroup differences only showed a significant association between lymphocyte increase and tetanus/diphtheria vaccine administration. A significant post-vaccine decrease in autoantibody positivity was observed. Autoantibodies were also studied by microarray analysis of self-proteins in subjects exposed to ≥4 concurrent vaccinations, without observing significant difference among baseline and one and nine months post-vaccine. Moreover, HLA-A2 subjects have been analyzed for the possible CD8T-cell response to apoptotic self-epitopes, without observing significant difference between baseline and one month post-vaccine. Multiple vaccinations in young adults are safe and not associated to autoimmunity/lymphoproliferation onset during a nine-month-long follow-up.

Neck pain in F-16 vs. Typhoon fighter pilots.

INTRODUCTION: In jet pilots, the neck is stressed by dynamic loading and there is growing concern about possible neck damage in pilots of new agile aircraft. Jet pilots often report neck pain after flight so intense that their operational capability may be affected. However, there is no clear evidence of structural damage related to the operational exposure. METHODS: We compared 35 F-16 pilots with 35 age-matched Eurofighter Typhoon pilots. All subjects completed an anonymous questionnaire on their flight activity and neck pain. RESULTS: The incidence of neck pain in the F-16 group was 48.6% compared with 5.7% of the Typhoon group, significantly higher. In F-16 pilots, there was a significant association between neck pain and age over 30 yr, total flight hours, and flight hours exceeding 600. DISCUSSION: Our findings suggest that the risk of neck pain after flight is higher among F-16 pilots compared with Typhoon pilots. This could be due to several reasons, including the backward reclined seat of the F-16, which exposes the neck to the load in an unfavorable posture while moving the head during maneuvers at sustained high-G.

Gender differences in navigational memory: pilots vs. nonpilots.

INTRODUCTION: The coding of space as near and far is not only determined by arm-reaching distance, but is also dependent on how the brain represents the extension of the body space. Recent reports suggest that the dissociation between reaching and navigational space is not limited to perception and action but also involves memory systems. It has been reported that gender differences emerged only in adverse learning conditions that required strong spatial ability. METHODS: In this study we investigated navigational versus reaching memory in air force pilots and a control group without flight experience. We took into account temporal duration (working memory and long-term memory) and focused on working memory, which is considered critical in the gender differences literature. RESULTS: We found no gender effects or flight hour effects in pilots but observed gender effects in working memory (but not in learning and delayed recall) in the nonpilot population (Women's mean = 5.33; SD= 0.90; Men's mean = 5.54; SD= 0.90). We also observed a difference between pilots and nonpilots in the maintenance of on-line reaching information: pilots (mean = 5.85; SD=0.76) were more efficient than nonpilots (mean = 5.21; SD=0.83) and managed this type of information similarly to that concerning navigational space. In the navigational learning phase they also showed better navigational memory (mean = 137.83; SD=5.81) than nonpilots (mean = 126.96; SD=15.81) and were significantly more proficient than the latter group. DISCUSSION: There is no gender difference in a population of pilots in terms of navigational abilities, while it emerges in a control group without flight experience. We found also that pilots performed better than nonpilots. This study suggests that once selected, male and female pilots do not differ from each other in visuo-spatial abilities and spatial navigation.

Deficits in visuo-spatial but not in topographical memory during pregnancy and the postpartum state in an expert military pilot: a case report.

BACKGROUND: It is well known that cognitive and emotional changes occur during pregnancy, but little is known about their magnitude or their time of occurrence and recovery. During pregnancy memory is one of the most impaired cognitive functions. Although long-term aspects of memory have been investigated, other aspects of memory have not yet been explored (i.e., navigational memory and reaching memory). CASE PRESENTATION: Here we describe the changes in reaching and walking memory that occurred during pregnancy and one year after delivery in an Italian female military pilot (Case 1) with high spatial ability. In memory tests she showed a classical dissociation between performance in reaching and walking distance, which indicated a failure of working memory, learning, and storage in reaching space. This suggests that her expertise served as a protective factor mitigating her low walking memory performance, and saving the topographical component.We compared her performance with that of two non-pregnant control groups (i.e., women pilots and non-pilots) and found that Case 1's reaching memory performance was significantly worse than that of the control groups. Even one year postpartum, Case 1's performance was not yet the same as that of the other pilots. CONCLUSIONS: These findings contribute to our knowledge of the specific, as yet unexplored, aspects of memory deficits in women pilots during pregnancy and postpartum and suggest the need for better neuropsychological assessment before these women return to work in operational environments.

Gender effects on mental rotation in pilots vs. nonpilots.

INTRODUCTION: Mental rotation ability has an important role in human navigation and, together with other cognitive abilities such as processing speed, working memory, and attention, is crucial for aircraft navigation. In the human performance literature, mental rotation tasks have consistently yielded reports of gender differences favoring men. The aim of this study was to compare the gender difference measured in a specialized population of aviators vs. a matched population of nonpilots. METHODS: : Studied were 41 pilots (20 men and 21 women) and 38 nonpilots (20 men and 18 women) matched for age and education. Pilots were stratified for flying hours. Participants performed a mental rotation task (MRT) in which accuracy and response time were recorded, and also completed sense-of-direction (SOD) and spatial cognitive styles self-evaluation scales. RESULTS: Men had significantly smaller response time in the MRT (men 279.6 +/- 147.0 s, women 401.6 +/- 361.3) and greater SOD (men's score 49.1 +/- 8.6, women's score 46.6 +/- 7.8), but these differences were absent among pilots. A positive relationship was also identified between pilots' response times and their flight hours. CONCLUSION: These data suggest that the effect of gender on the speed of cognitive spatial processing is absent in a population with aviation experience. Gender effects may be associated with a low spatial cognitive style, whereas in groups such as aviators, who are expected to have high spatial cognitive style, other factors such as experience may come into play.

Cerebral vascular response in airmen exposed to hypobaric hypoxia.

INTRODUCTION: Cerebral vascular response via local and reflex adjustments is part of the integrated response to hypoxia and is coupled with changes in systemic vascular resistances that allow a redistribution of blood flow toward the brain. The cerebral vascular response in airmen exposed to simulated high altitude is not clear, thus we sought to investigate this aspect. METHODS: Four healthy military airmen were exposed to simulated high altitude in a hypobaric chamber according to a standard training protocol. Blood saturation (SpO2) and blood flow velocity with transcranial Doppler from the left middle cerebral artery (Vm) were continuously recorded. Pulsatility Index (PI), resistance index (RI), and systolic/diastolic ratio (S/D ratio) were computed. Alternate hypoxia-hyperoxia trials for 2 and 1 min, respectively, were used to assess the cerebrovascular response. RESULTS: Acute hypoxia induced an increase in Vm that promptly recovered when the oxygen supply was restored (mean increase of 5.5% at 18,000 ft and 17.2% at 25,000 ft). Alternate hypoxia-hyperoxia at 25,000 and 18,000 ft elicited changes in both SpO2 and Vm. In hypoxia, PI significantly decreased (mean decrease o" 25.6% at 18,000 ft and 39.5% at 25,000 ft), as did RI (mean decrease of 18.7% at 18,000 ft and 34.4% at 25,000 ft), while S/D ratio increased. DISCUSSION: The standard altitude training protocol induced a transient cerebrovascular response. The response was as expected, with hypoxia-induced vasodilation and opposite changes when breathing pure oxygen.

Subjective visual vertical in erect/supine subjects and under microgravity: effects of lower body negative pressure.

Perception of the subjective visual vertical (SVV) is mainly based on the contributions from the visual, vestibular, and proprioceptive systems, and participates to the process of spatial orientation in relation to the surrounding environment and to the gravito-inertial force. The SVV can be significantly influenced by the presence of a displaced visual field, as in the case of the rod and frame test (RFT). A series of studies showed the effects of haematic mass shifts to and from the lower limbs on SVV, due to visceral mechanoreceptors (VM) located at the level of the kidneys and of the thorax. These sensors may be artificially activated with a lower body negative pressure (LBNP) device. In this study, the role of visual and VM cues to orientation perception have been evaluated using the RFT and the LBNP devices under a microgravity environment. A preliminary investigation was conducted in a sample of military pilots to develop a RFT protocol to be used in microgravity environments. This protocol was adopted to evaluate the contribution of VM to the SVV in a cosmonaut before, during and after a 10 day space flight, with and without concurrent activation of LBNP. The same test sequence, including LBNP exposure, was repeated a few months later on Earth on the same subject. As expected, the influence of the frame on rod positioning was statistically significant in all test conditions. During the in-flight experimental step, a substantial lack of significant changes compared to the pre-flight condition was observed. Moreover, substantially no effects due to LBNP were observed. A mild rod displacement from the body axis was detected under microgravity compared to the pre-flight recording. Such a finding was in part reduced during LBNP. The same findings were observed during the post-flight repetition of the experiment. Our results showed an absence in this subject of significant effects on the RFT due to microgravity. In conclusion, no effects from his VM on the RFT and minor changes in the SVV could be detected.

Luteinizing hormone (LH) levels in male workers exposed to urban stressors.

The aim of the study is to evaluate if occupational exposure to urban stressors could cause alterations in luteinizing hormone (LH) plasma levels in male traffic policemen vs. administrative staff of Municipal Police.After excluding the subjects with the main confounding factors, male traffic police and administrative staff of Municipal Police were matched by age, working life, body mass index (BMI), alcohol drinking habit, cigarette smoking habit and habitual consumption of Italian coffee.In 166 male traffic police mean LH values were significantly higher compared to 166 male administrative employees. The distribution of LH values in traffic police and in administrative employees was statistically significant.Our results suggest that recent exposure to urban stressors (chemical, physical and psycho-social) can alter the plasma concentration of LH. In agreement with our previous research, levels of plasma LH may be used as early biological markers, valuable for the group, used in occupational set before the appearance of the disease.

Hemopoietic system in traffic police exposed to urban stressors.

The aim of the study is to evaluate if occupational exposure to urban stressors could cause alterations in red blood cells (RBC), hemoglobin (HGB), hematocrit (HCT), mean cell volume (MCV), mean cell hemoglobin (MCH), mean corpuscular hemoglobin concentrations (MCHC) in traffic police compared to a control group. 694 subjects were included in the study: 347 traffic police and 347 controls matched by sex, age and length of service after excluding the subjects with the principal confounding factors. The levels of RBC, HGB, HCT were significantly higher in male (respectively p<0.001, p<0.05, p<0.01) and in female (respectively p<0.05, p<0.001, p<0.01) traffic police than in controls. The authors hypothesise that occupational exposure to urban stressors in traffic police can alter hemopoietic system.

Exposure to urban stressor and effects on free testosterone in female workers.

BACKGROUND: The aim of the study is to evaluate if occupational exposure to chemical, physical and psycho-social urban stressor could cause alterations in plasma free testosterone (T) levels and related diseases in female traffic police vs. control group. PATIENTS AND METHODS: The research was carried out on initial sample of 468 female Municipal Police employees (209 traffic police and 259 controls). After excluding the principal confounding factors, traffic police were matched with controls by age, working life, menstrual cycle day, BMI, drinking habit, cigarette smoking habit, liquorice and soy intake in diet, habitual consumption of Italian coffee. There were 96 female traffic police and 96 controls included in the study. RESULTS: T mean levels were significantly higher in female traffic police compared to controls (p=0.000). The distribution of T values in traffic police and in controls was significant (p=0.000). No significant differences were found comparing the percentage in traffic police and controls concerning dystocial, premature and post-term birth. An increase in mental health disorders was found in traffic police compared to controls but the difference was not significant. CONCLUSION: The increase in T plasma levels observed in traffic police vs. controls can be due to a chronic working exposure to low doses of environmental chemical urban stressor. According to our previous researches T could be used as an early biological marker even before the onset of the related disorders.

Exposure to traffic pollutants and effects on 17-beta-estradiol (E2) in female workers.

OBJECTIVE: The aim of the study is to evaluate whether the occupational exposure to urban pollutants including endocrine disruptors (EDs) could cause alterations in plasma 17-beta-estradiol (E2) levels and related diseases (adverse pregnancy outcome and mental health disorders) in female traffic police compared to a control group. METHODS: After excluding the subjects with the principal confounding factors, traffic police and controls were matched by age, years of police work, age of menarche, menstrual cycle day, body mass index (BMI), drinking habit, cigarette smoking habit, habitual intake of soy or liquorice in diet and habitual consumption of Italian coffee. Thirty-seven traffic police and 31 controls (seventh day; follicular phase of the ovarian cycle); 38 traffic police and 42 controls (14th day; ovulatory phase of the ovarian cycle); and 25 traffic police and 28 controls (21st day; lutheal phase of the ovarian cycle) were included in the study and then matched for the above-mentioned variables. RESULTS: In follicular and in lutheal phases, mean E2 levels were significantly lower in traffic police compared to controls. The distribution of E2 values in traffic police and controls was significant in follicular, ovulatory and lutheal phases. In ovulatory phase, mean E2 levels were lower but not significant in traffic police compared to controls. An increase was found concerning mental health disorders referred to in the questionnaire items in traffic police compared to controls, although the difference was not significant. CONCLUSIONS: Considering that the potential confounding effect of extraneous factors was controlled for by restricting the study population and by matching traffic police and controls on the above-mentioned variables, our results suggest that occupational exposure to urban pollutants, EDs included, might alter E2 plasma concentrations. E2 could be used in occupational set as an early biomarker of exposure to urban pollutants, valuable for the group, even before the onset of the related pathologies (adverse pregnancy outcome and mental health disorders).

Occupational exposure to noise and hypertension in pilots.

The role of occupational exposure to noise as a hypertension risk factor has not been established sufficiently. The aim of the study is to evaluate whether chronic exposure to different levels of noise in two groups of pilots, operating with two types of aircraft, could be a risk for hypertension, what relevance the parameters (intensity, duration and type) of exposure can have and, lastly, whether there are any links between hearing impairment and hypertension. After excluding pilots with confounding factors, a study was made of 77 male pilots of turboprop planes (group A) and 224 male pilots of jet aircraft (group B), matched by age and working life. Blood pressure (supine and standing positions) and heart rate were measured. Electrocardiogram, stress tests on a cycle ergometer, sound-level measurement and audiometric tests were also done. Pilots of group A were exposed to Leq of 93 dBA while pilots of group B were exposed to the Leq of 79 dBA. Significant results in group A compared to group B were found between heart rate, blood pressure, drop in blood pressure, parameters (intensity, duration and type) of exposure to noise and between hearing damage and hypertension. The findings suggest that chronic exposure to noise is a risk factor for blood hypertension in pilots exposed to high noise levels, and that the drop in blood pressure may be a sign of more sensitive effect of noise on blood pressure, according to other studies in literature.

Occupational exposure to urban pollutants and plasma insulin.

OBJECTIVE: The aim of this study was to investigate whether traffic police of a big city who are exposed to urban pollutants are at risk to alterations in plasma insulin concentrations compared with controls. METHODS: The class of workers examined in this study were employees of the municipal police in Rome, Italy. The study was carried out during the period March-April 2001. Traffic police were matched with a control group, where gender, age, working life and drinking habit were noted. A total of 246 traffic police (128 men and 118 women) with outdoor activity and exposure to urban pollutants and 242 subjects (128 men and 114 women) with indoor activity were included in the study. RESULTS: The levels of plasma insulin were significantly lower in traffic police compared to the control group of both gender. CONCLUSION: Plasma insulin level was altered in traffic police who are exposed to chemical and physical stressors.

Exposure to urban pollutants and serum levels of IgG anti Herpes Simplex virus type 1.

The aim of the study is to investigate whether traffic policemen exposed to urban pollutants and psycho-social stressors may be at risk of modifications in serum levels of immunoglobulins G antibodies (IgG Ab) against Herpes Simplex Virus (type1) (HSV-1) compared with controls. Traffic policemen were matched by sex, age, working life and drinking habits (less than two glasses of wine or beer per day) with controls, after excluding the subjects with the principal confounding factors (smoking habit, use of paints, solvents, pesticides and drinking habits). Were included in the study 125 traffic policemen (54 men and 71 women) with outdoor activity and 125 controls (54 men and 71 women) with indoor activity. Mean levels of IgG Ab against HSV-1 were significantly higher in traffic policemen of both sexes compared with controls. The frequency of workers with IgG Ab against HSV-1 levels higher than our normal laboratory values, was significant in traffic policemen compared with controls of both sexes. The distributions of IgG Ab against HSV-1 levels in traffic policemen compared with controls of both sexes were significant. The authors hypothesise an effect of the working activity in traffic policemen on serum levels of IgG Ab against HSV-1 compared to controls.

Ambulatory (24 hour) blood pressure monitoring in police officers.

The aim of the study is to evaluate, by ambulatory (24 h) blood pressure monitoring (ABPM), whether police officers exposed to urban pollutants and possible psycho-social stressors could be at risk of changes in ambulatory systolic blood pressure (SBP), and ambulatory diastolic blood pressure (DBP) compared to controls. After excluding the principal confounding factors, police officers and controls have been subdivided into non-smoker and smoker subjects. Police officers were compared by sex, age, length of service, family history of cardiovascular disease, serum total cholesterol, serum HDL cholesterol, serum LDL cholesterol, plasma triglyceride, body mass index (BMI kg/m (2)) and drinking habits with controls. Smoker police officers were compared with controls also by the smoking habit. In the non smoker group 77 police officers with outdoor activity (38 men and 39 women) and 87 controls with indoor activity (43 men and 44 women) were studied. In the smoker group 43 police officers (21 men and 22 women) and 29 controls (15 men and 14 women) were studied. In non smoker male police officers ambulatory SBP mean values during 24 h, during day-time and during night-time were significantly higher than controls. In the same group ambulatory DBP values during 24 h and between 6 AM and 11 AM and between 10 PM and 6 AM were significantly higher in police officers than controls. The results suggest that occupational exposure to urban pollutants and possible psycho-social stressors could cause changes in ABPM values in male police officers compared to controls.

Occupational exposure to urban pollutants and plasma insulin-like growth factor 1 (IGF-1).

The aim of present study is to evaluate whether traffic policemen exposed to urban pollutants and possible psycho-social stressors could be at risk of alterations on plasma insulin-like growth factor (IGF-1) levels compared to a control group. Out of a population of 395 Municipal Police employees, the subjects with principal confounding factors (cigarette smoking habits, drinking habits, oral contraceptives being taken, use of paints, solvents and pesticides) were excluded from the study. The remaining traffic policemen were matched with those not exposed by sex, age and length of service; 49 traffic policemen (22 men and 27 women) with outdoor activity exposed to urban pollutants and 49 not exposed subjects (22 men and 27 women) with indoor activity were included in the study. The plasma levels of IGF-1 resulted significantly higher in the male and female traffic policemen compared with control subjects (respectively P<0.001; P<0.001). The authors hypothesise that occupational exposure to chemical stressors, that may interact with possible psycho-social stressors, could cause an alteration on IGF-1 levels in traffic policemen.

Exposure to urban pollutants and plasma vasopressin in traffic policemen.

OBJECTIVES: The aim of the present study is to investigate whether traffic policemen of a big city exposed to urban pollutants may be at risk of alterations on plasma vasopressin (VP) concentrations compared with a control group. MATERIAL AND METHODS: Out of a population of 395 Municipal Police employees, the subjects with the principal confounding factors were excluded from the study. Traffic policemen and control subjects were matched by sex, age and working life. Plasma VP levels were determined in 82 subjects: 41 traffic policemen (18 men, 23 women) and 41 control subjects (18 men, 23 women). RESULTS: Mean of VP values were found significantly lower in traffic policemen than in the control group both in men (P=0.010) and in women (P=0.015). We found high correlation between VP values and working life in traffic policemen of male and female sex (r=0.7; r=0.6). DISCUSSION: The authors hypothesise an effect on plasma VP levels in traffic policemen exposed to chemical and physical stressors, according to plasma VP levels modifications found by other authors in studies on animals and human subjects.