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The purpose of the study was to assess non-dietary exposure of workers and the general population in the Paris area to some organophosphorus (OP) pesticides. In total, 21 workers from different occupational places (two greenhouses, three florist shops and three veterinary departments) and 20 subjects assumed to be non-occupationally exposed were recruited. Indoor air, hand wipes, and three first morning urine samples were collected. Seven OPs were measured by GC/ECD and GC/TSD, and six urinary dialkylphosphate metabolites by GC/PFPD. All indoor air samples from the workplaces and only one-third of the samples from the residences contained at least one of the seven OPs. However, almost all participants were dermally exposed to OPs. Total OP indoor air and cutaneous levels were significantly higher for workers than for the general population (air median = 185 pmol/m3 versus nondetectable, P < 0.0001; hands median = 1250 pmol/hands versus 475 pmol/hands, P = 0.03). From the air, gardeners and florists were mainly exposed to methyl-OPs and veterinary staff to ethyl-OPs (mainly diazinon). From their hands, all subjects were exposed to methyl-OPs, with gardeners and florists exposed to somewhat but not significantly higher levels. Ethyl-OPs were more found frequently and at higher levels on the hands of veterinary workers. Total OP levels in indoor air and from hand wipes were significantly correlated (Spearman R = 0.34, P = 0.03). DAP detection frequencies and levels were not different between workers and the general population (workers median=168 nmol/g creat and general population median = 241 nmol/g creat, P = 0.31), and did not correlate with air or hand levels. Subjects not occupationally exposed showed significant residential exposure to OPs, more frequently from their hands than from the air. Different occupations were associated with different exposure profiles and levels. The lack of differences in DAP levels between the different groups of exposure suggests that dietary exposure to OP residues and exposure to other OPs are involved.

This study applies a traffic exhaust air dispersion model (the ExTra index) to 403 children enrolled in a French multicentric case-control study, the VESTA study (Five [V] Epidemiological Studies on Transport and Asthma). The ExTra index (previously validated by our team) was used to assess lifelong average traffic-related air pollutant (TAP) concentrations (nitrogen oxides) children in the study were exposed to in front of their living places. ExTra index took into account traffic density, topographical parameters (building height, road and pavement width), weather conditions (wind direction and strength) and background pollution levels. Topographical and traffic data were collected, using a specific questionnaire for each home, school or nursery address, attended by children. The assessment of time-weighted NOx levels in front of the children's living places highlighted significant disparities: mean ExTra index values and share attributable to proximity traffic were, respectively, 70+/-42 and 14+/-22 microg/m3 NOx equivalent NO2 for the 403 children in our study. Not only would this diversity not have been revealed using urban background pollution data provided by air quality networks, it would have resulted in 40% of the children being misclassified with regard to their TAP exposure by underestimating it in half of the cases and overestimating it in the other half. Such errors of classification, which are highly prejudicial in epidemiology, argue strongly for the use of an index such as the ExTra, which enables TAP exposure to be reconstructed within the framework of retrospective or prospective epidemiological studies.

Associations between average total personal exposures to PM2.5, PM10, and NO2 and concomitant outdoor concentrations were assessed within the framework of the Genotox ER study. It was carried out in four French metropolitan areas (Grenoble, Paris, Rouen, and Strasbourg) with the participation, in each site, of 60-90 nonsmoking volunteers composed of two groups of equal size (adults and children) who carried the personal Harvard Chempass multipollutant sampler during 48 h along two different seasons ("hot" and "cold"). In each center, volunteers were selected so as to live (home and work/school) in three different urban sectors contrasted in terms of air pollution (one highly exposed to traffic emissions, one influenced by local industrial sources, and a background urban environment). In parallel to personal exposure measurements, a fixed ambient air monitoring station surveyed the same pollutants in each local sector. A linear regression model was accommodated where the dependent pollutant-specific variable was the difference, for each subject, between the average ambient air concentrations over 48 h and the personal exposure over the same period. The explanatory variables were the metropolitan areas, the three urban sectors, season, and age group. While average exposures to particles were underestimated by outdoor monitors, in almost all cities, seasons, and age groups, differences were lower for NO2 and, in general, in the other direction. Relationships between average total personal exposures and ambient air levels varied across metropolitan areas and local urban sectors. These results suggest that using ambient air concentrations to assess average exposure of populations, in epidemiological studies of long-term effects or in a risk assessment setting, calls for some caution. Comparison of personal exposures to PM or NO2 with ambient air levels is inherently disturbed by indoor sources and activities patterns. Discrepancies between measurement devices and local and regional sources of pollution may also strongly influence how the ambient air concentrations relate to population exposure. Much attention should be given to the selection of the most appropriate monitoring sites according to the study objectives.

Background: Automobile exhaust is a major source of air pollution in urban areas. To study health effects of traffic exhaust fumes epidemiologists need specific tools in order to achieve a precise assessment of human exposure to traffic air pollution (TAP) and avoid misclassification. The aim of this review is to study the different ways of assessing human exposure to TAP in epidemiological studies dealing with short-term or long-term health effects of TAP., Methods: After presenting the different designs and goals of the studies mentioned above, this review focuses on methods of assessing exposure to TAP and their different associated health endpoints., Results: To assess exposure to TAP, most published studies have used more or less complex exposure indices. Several teams have used residence location and its proximity to traffic, traffic counts, or a combination of both. More recently, some authors have developed mathematical dispersion models and statistical regression models., Discussion: Our analysis shows that reliable and validated tools would be needed to assess accurately human exposure to TAP. This can only be achieved with statistical regression models and mathematical dispersion models. Although such methods may be difficult to implement, their use can be facilitated by adding a geographic information system.

The ExTra index, produced by the French Scientific Center for Building Physics, evaluates ambient concentrations of transport-related pollutants in front of the work and living places of urban dwellers. This study contributes to the validation of the ExTra index by carrying out measurements in four French cities. It compares nitrogen oxide concentrations (NOx) measured over 6 weeks with passive samplers, and NOx calculated concentrations using the ExTra index. The study takes into account traffic density, topographical parameters (building height, road, and pavement width), weather conditions (wind direction and strength), and background pollution levels. The model was tested at 100 street canyons sites. There were highly significant correlations (0.90 in Grenoble, 0.95 in Nice, 0.89 in Paris, and 0.89 in Toulouse) and good intraclass correlation coefficients (0.75 in Grenoble, 0.91 in Nice, 0.89 in Paris, and 0.86 in Toulouse) between the two series of values. These results suggest that if the ExTra index were to be applied to all the different residences and workplaces of a subject throughout his (her) life, it could be a useful epidemiological tool for studying the long-term health effects of transport-related emissions and for reconstructing individual exposure to such pollution in order to avoid misclassification.

Few studies have been conducted on the effects of air pollution on patients with chronic obstructive pulmonary disease (COPD). During a 14-mo period, 39 Parisian adults with severe COPD were monitored by their physicians. Daily levels of 4 air pollutants were provided by an urban air-quality network. Exacerbation of COPD was associated only with ozone (O3) (odds ratio [OR] = 1.44 for a 10-microg/m3 increase in O3; 95% confidence interval [CI] = 1.14, 1.82), with a lag of 2-3 days. The effect of O3 was greater in patients whose carbon dioxide pressure (PaCO2) was higher than 43 mm Hg (OR = 1.83; 95% CI = 1.36, 2.47) vs. those with a lower PaCO2 (OR = 1.26; 95% CI = 0.90, 1.77). The effect of O3 was unchanged, regardless of the maintenance medications used. The only air pollutant to which patients with severe COPD were particularly sensitive was O3.

Several studies among adult populations showed that an array of outdoor and indoor sources of particles emissions contributed to personal exposures to atmospheric particles, with tobacco smoke playing a prominent role (J. Expo. Anal. Environ. Epidemiol. 6 (1996) 57, Environ. Int. 24 (1998) 405, Arch. Environ. Health 54 (1999) 95). The Vesta study was carried out to assess the role of exposure to traffic emissions in the development of childhood asthma. In this paper, we present data on 68 children aged 8-14 years, living in the metropolitan areas of Paris (n = 30), Grenoble (n = 15) and Toulouse (n = 23), France, who continuously carried, over 48 h, a rucksack that contained an active PM2.5 sampler. Data about home indoor sources were collected by questionnaires. In parallel, daily concentrations of PM10 in ambient air were monitored by local air quality networks. The contribution of indoor and outdoor factors to personal exposures was assessed using multiple linear regression models. Average personal exposure across all children was 23.7 microg/m3 (S.D. = 19.0 microg/m3), with local means ranging from 18.2 to 29.4 microg/m3. The final model explains 36% of the total between-subjects variance, with environmental tobacco smoke contributing for more than a third to this variability; presence of pets at home, proximity of the home to urban traffic emissions, and concomitant PM10 ambient air concentrations were the other main determinants of personal exposure.

To evaluate the relationship between clinical parameters and differential cell counts, bronchoalveolar lavage was performed in 79 asthmatic infants and children with unusual asthma. Multivariate analysis showed significant associations between (1) allergic asthma and the presence of alveolar eosinophils and (2) persistent and longer asthma and an increased number of alveolar neutrophils. Our results provide the first evidence that in asthmatic infants and children eosinophilic inflammation is related to allergic sensitization.

Background: Personal exposure to air pollutants and ambient air measurements are poorly correlated in the short term. Nevertheless, air quality surveillance data are often used to characterize exposure in epidemiological studies. This work explores a method to derive exposure estimates for a population of children, through appropriate usage of surveillance data that allows for heterogeneity of life environments., Methods: Personal exposure (PE) to PM2.5 and NO(2) of 66 to 184 children was measured in 4 French metropolitan areas (Grenoble, Nice, Toulouse and Paris). The proposed approach provides an estimate of a "translator parameter". This method was applied to subgroups of children who differed in terms of daily time spent in areas more or less influenced by traffic emissions., Results: Ambient air concentrations of NO(2) overestimated personal exposures, on average, but children whose life environments are more influenced by traffic exhausts exhibit, on average, greater PE values; as far as particles are concerned, air quality surveillance and PE values are closer. Hence, translation parameters differ according to pollutants, cities and populations., Conclusions: These results suggest that ambient air monitors can be used to assess exposure of urban populations living in areas with variable traffic intensities. However, usage of these air quality surveillance data should allow for population and pollutant characteristics.

A case-control study was conducted in five French metropolitan areas in order to assess the role of traffic-related air pollution in the occurrence of childhood asthma. This paper presents the study design and describes the distribution of key exposure variables. A set of 217 pairs of matched 4- to 14-year-old cases and controls were investigated (matching criteria: city, age, and gender). Current and past environmental smoke exposures, indoor allergens or air pollution sources, and personal and family atopy were assessed by standard questionnaires. When possible, direct measurements were done to check the validity of this information, on current data: skin prick tests, urine cotinine, house dust mites densities, personal exposures to, and home indoor concentrations of NO(x) and PM(2.5). Cumulative exposure to traffic-related pollutants was estimated through two indices: "traffic density" refers to a time-weighted average of the traffic density-to-road distance ratio for all home and school addresses of each child's life; "air pollution" index combines lifelong time-activity patterns and ambient air concentration estimates of NO(x), using an air dispersion model of traffic exhausts. Average current PM(2.5) personal exposure is 23.8 microg/m3 (SD=17.4), and average indoor concentrations=22.5 microg/m3 (18.2); corresponding values for NO(2) are 31.4 (13.9) and 36.1 (21.4) microg/m3. Average lifelong calculated exposures to traffic-related NO(x) emissions are 62.6 microg/m3 (43.1). The five cities show important contrasts of exposure to traffic pollutants. These data will allow comparison of lifelong exposures to indicators of traffic exhausts between cases and controls, including during early ages, while controlling for a host of known enhancers or precipitators of airway chronic inflammation and for possible confounders.

Only a few studies have been carried out on the health effects of air pollution on patients suffering from severe asthma. We wanted to test the sensitivity of these patients to Paris air pollution. During 13 months, 60 severe asthmatics (62- female; mean age 55 years) were monitored by their physician, who filled in a follow-up form at each consultation and reported any asthma attacks. Daily levels of SO(2), PM10, NO(2), and O(3) were provided by the air quality network. Statistical analysis (generalized estimating equation models that accounted for autocorrelation of responses, temporal, meteorological, and aerobiological variables, and some individual characteristics) revealed significant associations between PM10, O(3), and incident asthma attacks. Odds Ratio (OR) for an increase of 10 microg/m(3) of PM10 was 1.41; 95% confidence interval (CI) [1.16; 1.71]. An increase of 10 microg/m(3) of O(3) was significantly associated with asthma attacks; OR=1.20; 95% CI [1.03; 1.41]. These relations were observed after a delay between exposure and asthma attacks of 3 to 5 days for PM10 and 2 days for O(3), and they tended to differ according to atopic status. The results of our study suggest that ambient Paris levels of PM10 and O(3) affected health of severe asthmatics, despite their treatment., (2002 Elsevier Science (USA))

The prevalence of respiratory allergies has increased over the last 20 years, highlighting the need for a simple and noninvasive tool to investigate, in a clinical and epidemiological context, airway-inflammation mechanisms encountered in allergic and inflammatory processes. The nose, as the first region of the respiratory tract to come in contact with airborne pollutants, is easily explored with the use of nasal lavage (NL). We evaluated an NL method for adults and children, along with its reproducibility and capacity to separate different subgroups. NL reproducibility, assessed in 10 healthy, nonsmoking adults on three different occasions, was determined with the use of the intraclass coefficient of correlation for such inflammatory markers as total cell count, albumin, urea, neutrophil elastase, alpha(1)-antitrypsin, interleukin-6, and interleukin-8. Using this NL method, we analyzed nasal markers of 50 healthy adults (smokers and nonsmokers) and 12 healthy children. Our NL method demonstrated high reproducibility with regard to total cell count, albumin, urea, and alpha(1)-antitrypsin (intraclass correlation coefficient > 0.75). Compared with NL results in nonsmokers, NL in heavy smokers revealed significant increased concentrations of total cell counts and interleukin-8 and significant decreased concentrations of interleukin-6. These findings suggest that NL can be used as a tool in the assessment of inflammation because it has the correct reproducibility and can discriminate between heavy smokers and nonsmokers. Moreover, the use of this standardized method in children is feasible.

French researchers from the Building Scientific and Technical Center have produced a traffic-exposure index. To achieve this, they used an air pollution dispersion model that enabled them to calculate automobile pollutant concentrations in front of subjects' residences and places of work. Researchers used this model, which was tested at 27 Paris canyon street sites, and compared nitrogen oxides measurements obtained with passive samplers during a 6-wk period and calculations derived from the model. There was a highly significant correlation (r = .83) between the 2 series of values; their mean concentrations were not significantly different. The results suggested that the aforementioned model could be a useful epidemiological tool for the classification of city dwellers by present-or even cumulative exposure to automobile air pollution.

We evaluated individual adipose tissue (subcutaneous lipomas) dioxin contamination in non-occupationally exposed persons living in France (adult patients undergoing a surgical ablation of benign lipomas), in relation to the corresponding individually evaluated mean daily dietary dioxin intake (DDDI). The diet survey (questionnaire) included information on consumption of meat, fish, milk and dairy products, from which the individual DDDI was calculated. Sixteen subjects participated in this study. DDDI ranged between 1.06 and 3.31 pg I-TEQ/kg body weight, bw (mean value: 2.05+/-0.72). Adipose tissue polychlorinated dibenzo-p-dioxins (PCDD)/polychlorinated dibenzofurans (PCDF) levels ranged between 18.5 and 76.9 pg I-TEQ/g lipids (mean value: 35.6+/-14.8). No relation was found between the DDDI and adipose tissue PCDD/PCDF concentrations. The mean DDDI in France does not fundamentally differ from those found in other industrialised countries, is within the range of 1-4 pg I-TEQ/kg/day recently suggested by WHO-ECEH/ICPS for the tolerable daily intake of dioxins. Adipose tissue PCDD/PCDFs levels are similar to levels in other European countries and USA without relation to sex or age, and can be considered representative European background concentrations. Globalisation of alimentary production leads to a similar food exposure in Western European countries, in spite of dioxins accidental selective contaminations that are epiphenomenon and thus do not have any impact in human dioxin background levels.

In epidemiological studies, investigators have routinely used ambient air concentrations, measured by air-quality monitoring networks, to assess exposure of subjects. When there is great spatial variability of ambient air concentrations or when there are specific indoor exposures, this approach may yield substantial exposure misclassification and distort the associations between exposure and the health endpoints of interest. In 3 French metropolitan areas, the cross-sectional relationships between 48 hr of nitrogen dioxide personal exposure of 73 children and the corresponding 48-hr background ambient air concentrations were analyzed. The crude correlation between ambient air concentrations and personal exposures was poor in all cities (r2 = .009 for Grenoble, r2 = .04 for Toulouse, and r2 = .02 for Paris). These correlations were improved when the authors took into account other ambient air or indoor air sources of nitrogen dioxide emissions (the corresponding multiple linear regression, r2, increased to .43 in Grenoble, .50 in Toulouse, and .37 in Paris). The main variables that explained personal exposures were an index of traffic intensity and proximity and use of a gas cooker at home. The results of this study confirm that ambient air-monitoring site measurements are poor predictors of personal exposure. Investigators should carefully characterize the proximity of roads occupied by dense traffic to the home/school as well as indoor sources of nitric oxide emissions; both of these careful characterizations will assist researchers in the prediction of personal exposure in epidemiological studies.

Obesity is an important risk factor in public health. In Paris, few statistical data are available in this area. The purpose of the present study is to evaluate the prevalence of overweight and obesity in 10 years-old children attending Paris elementary schools (cours moyen deuxième année--CM2--last level of the elementary school). 148 classes were randomly selected, gathering 3,621 schoolchildren 10 years 6 months old. 66 doctors in charge of health at school participated in the study, doing the measurements of weight, size and collecting also the weight and size at birth and at the "grande section-GS-level" (last level of the infant school, 5 years-old children) from the individual health file of the schoolchildren. The statistical analysis was based on the study of distributions of the observed Quetelet index (Q0) at the different ages, compared to French reference curves. A logistic regression analysis was performed to determine whether birth weight and GS weight predict obesity in CM2. In GS and in CM2, observed Quetelet indices are over expected values: in CM2, 22.8% of boys and 25.6% of girls exceed the reference value Q90; the prevalence of obesity (Q0 > or = Q97) is 13.4% in boys and 13.5% in girls. Among the variables "term", "weight at birth", weight in GS level and "gender", the weight in GS level is the only predictive factor of obesity in CM2 level. The situation in Paris appears to be serious. Preventive actions are needed at early stages to try to stop and, if possible, to reverse the present increase of overweight. In this context, school doctors have to play a prominent role.

This review presents a synthesis of studies published from 1962 to 2000 on the relations between air pollution and chronic obstructive pulmonary disease (COPD): 12 ecological epidemiological studies, 6 epidemiological panel studies, and 11 controlled human exposure trials. The controlled trials, ecological time-based epidemiological studies and panels are examined successively followed by a discussion of their methodology and results. The controlled trials either do no highlight effects or show effects having no clinical significance since variations are similar to physiological variability. For epidemiological studies reporting individual data, the results point to a particle effect (two studies). This effect of particles is found in ecological studies which also describe an impact of ozone, sometimes of sulfur dioxide and less often of nitrogen dioxide. In conclusion, patients suffering from COPD are generally regarded as a group sensitive to air pollution, as suggested by the results of numerous ecological epidemiological studies. Rare individual studies provide a few arguments supporting this assumption.

Background: There are few studies of individual exposure to atmospheric particles, because of the relatively bulky and noisy sampling devices. These personalized measurements, generally associated with micro-environmental measurements, are aimed at studying the distribution of individual exposure and identifying its main determinants., Methods: A synopsis of the methods implemented in such studies (populations studied, measurements strategies, questionnaires on time-activity patterns, residences and work place) was detailed. The major results are presented and discussed from an epidemiological point of view., Results: The individual exposure measured with portable devices generally were generally found to be higher than the estimations made by combining micro-environmental (outdoor and indoor) measurements and data from time-activity diaries. The difference between results of these two approaches, known as "personal cloud", remains poorly understood. Correlations between individual measurings and outdoor concentrations are weak; nevertheless, day to day variations of these two series of measurements are better related. The main determinants of individual exposure to particles are identified but a quantification of their contribution remains difficult, except for passive smoking., Conclusion: Personal measurements cannot be used to estimate particle exposure in large scale epidemiological studies. This exposure needs to be modelized.

This paper gives an overview of the environmental or background exposure of general population to dioxins, polychlorinated dibenzo-para-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF), originating from a variety of industrial and thermal processes and recognized as cancerous and toxic substances. The daily consumption of low-level contaminated food, mainly of animal origin, leads to the accumulation of dioxins in the human body. To determine the background exposure, human milk, adipose tissue or blood from many geographical locations (except France) have been used as bioindicators for body burden of dioxins. Human milk also allows the daily intake estimation of dioxins for breast-fed babies. Efforts should be made to minimize or avoid PCDD/PCDF emission in the environment.

This article presents a synthetic study of 31 epidemiological panel investigations (published between 1987 and 1998) analyzing how air pollution and health may be related. First, the methodology of these studies is described: choice of population, exposure and health assessment, confounding factors and statistical methods. The main results are presented as follows: for pulmonary performance, respiratory symptoms and medication use per pollutant (PM10 and particles, SO2, O3, NO2). Then the interactions among pollutants or implying other environmental factors are analyzed. Most of the time, an association with particles is found, no matter the health indicator considered. An O3 effect is more often observed with lung function tests than with respiratory symptoms or medication use, the latter being linked first to particles and secondly to SO2. A NO2 effect is more rarely shown. Pulmonary performances are affected by all pollutants. Respiratory symptoms related to air pollution are mostly low respiratory symptoms and cough, particularly with particles and O3. The paper ends by discussing the interest and limits of these studies. It also emphasizes the importance of exposure assessment. Indeed, in order to improve exposure assessment, an essential step in every epidemiological study, new tools need to be developed.

This study was carried out in 280 patients in 1994 in five medico-social centres (CMS) in the city of Paris for the follow up of treatment tuberculous disease. The group represented approximately one fifth of the tuberculous patients in Paris. 90.7% of the subjects were of foreign origin, predominantly African. Amongst these 280 patients, 80% were unemployed and 64.6% without social security protection. Their tuberculous disease did not differ on clinical grounds from those of the general population but they were less often vaccinated with BCG. They are also less often co-infected with the HIV virus (4.4 vs 12-16%). The level of resistance to isoniazid and rifampicin was 1.4%. A cure was certainly achieved in 73.5% of the patients. For the remainder, the absence of information and the loss to follow up prevented us from having a definite answer. The patients lost to follow numbered 56 and represented 20% of the group.

To evaluate the usefulness of tobacco markers in dependent smokers being treated with transdermal nicotine patches, a study was conducted at the Tobacco Withdrawal Consultation Centre at the Hôpital Laennec, Paris, France. 125 patients were included in the study and, in a first time, carbon monoxide in exhaled air, carboxyhaemoglobin, urinary nicotine and cotinine, Fagerström index, were measured and correlated to the amount of nicotine inhaled per day. The most significant value was observed for cotinine. In a second time, 25 patients were followed clinically and biologically with urinary continine monitoring (group FC) and 73 were followed up only clinically (group FC). The success rate of therapy 12 weeks after the end of treatment was 72% in group FB and 28% in group FC. The nicotine patch dose was positively correlated (p < 0.01) with successful outcome. The lower the urinary cotinine level at 4 weeks, the more likely was successful outcome (p < 0.05). If psychological factors remain important, urinary cotinine monitoring in the course of nicotine patch treatment thus favours successful withdrawal.

This paper deals with subjects seeking counselling and testing for human immunodeficiency virus (HIV); it analyses which sociodemographic and behavioral characteristics are related to beliefs concerning HIV infection and to HIV seropositivity. A one month survey among individuals who attended HIV testing in three anonymous and free centers (CIDAGs) was carried out in Paris city, on March 1994. 2059 subjects completed a self-administered questionnaire. Data collected included demographic information, sexual and IVDU behavior, and HIV seropositivity. Subjects also had to evaluate their own risk of getting the acquired immunodeficiency syndrome (AIDS) and the perceived risk of getting AIDS in specific situations such as unprotected anal/vaginal intercourse with a casual partner, with multiple partners, with a seropositive partner, current dental treatment, French kiss, etc.... Multiple linear and logistic regressions have been used to model the dependent variables. Subjects correctly evaluated the risk level of HIV transmission associated with different situations, and women, young men and those engaged in homo/bisexual behavior were in general more conscious of the increased danger resulting from high risk sexual practices. Among males, homo/bisexuals, drug users and the less educated considered themselves to be more at risk. The most important factors related to HIV seropositivity were sexual orientation, intravenous drug use (IVDU), and the perceived risk of getting aids. Despite a good awareness of HIV contamination and an accurate perception of their own risk, many subjects continued to engage in high risk AIDS activities. Better targeted interventions need to be developed to promote and maintain behavior changes.

This study was designed to analyse sexual and drug use behaviour, to determine whether increased awareness can lead to behaviour change, and to evaluate the association between HIV seropositivity and potential risk factors. A 4-month survey was carried out on 147 IVDUs attending three HIV counselling and testing centres, 98% of whom had been using heroin for an average of 7 years, 85% in association with other drugs. Two-thirds of injectors reported having used "safer" injecting practices in the previous year. Most of the IVDUs were heterosexual, and had had an average of three sexual partners in the previous year. More than half of them had had high risk partners. Condoms were used by only 25% of IVDUs, and were more likely to be used with seropositive partners (38% versus 12.7%, p = 0.02). Patients considering themselves to be well informed about HIV transmission shared syringes significantly less often, but had the same sexual behaviour patterns as other subjects. The HIV prevalence rate (8.2%) in our sample was not statistically related to any risk factor apart from drug use duration, the latter possibly reflecting a cumulative exposure to HIV risks. Since sexual risk appears to be a potential long-term hazard for IVDUs, it is important that more attention be paid to providing counselling to specifically address this issue.

This paper is the first mortality cohort study undertaken in France to examine the association between fire-fighting and cause of death. The cohort investigated in this study consisted of 830 male members of the Brigade des sapeurs-pompiers de Paris (BSPP). These professional had served for a minimum of 5 years on 1 January 1977. They were monitored for a 14 year period, finishing 1 January 1991. When compared to the average French male, the Paris fire-fighters were found to have a far lower overall mortality (SMR = 0.52 [0.35-0.75]). None of the cause specific SMRs were significantly different from unity. However a greater number of deaths than expected was observed for genito-urinary cancer (SMR = 3.29), digestive cancer (SMR = 1.14), respiratory cancer (SMR = 1.12) and 'cerebrovascular disease' (SMR = 1.16). The low overall SMR observed was consistent with the healthy worker effect. As for cause specific SMRs, they will be confirmed or invalidated by a further analysis as the follow-up of this cohort is being carried on.

In the Mediterranean region of France where bladder cancer mortality and incidence are high, a case-control study with 219 male incident cases and 794 randomized, male population-controls was carried out in 1987-89 to investigate bladder cancer risk factors and more specifically, regional factors. A stepwise logistic regression was applied to the data. This investigation confirms the role of tobacco and of certain occupational exposures in bladder carcinogenesis. There was a significant dose-response relationship with lifelong coffee drinking and alcohol consumption; however the risk estimates were only significantly elevated for the heaviest drinkers. The intake of saccharin was not associated with risk of bladder cancer. Infrequent consumption of carrots, spinach, and marrows conferred an increased risk, suggesting a protective effect of vitamin A. Finally, this investigation results in some new hypotheses. The study of residences and birthplaces has revealed a lower risk for those who have lived in a non-Mediterranean area and a higher risk for those born in a Mediterranean area. These features might be explained by some Mediterranean dietary habits, such as a high consumption of spices (odds ratio = 3.64, 95 percent confidence interval = 2.21-5.98).

The excess of morbidity and mortality for cancers of the bladder in the french department of Hérault (South of France, on the side of the Mediterranean Sea) justified the implementation of a new epidemiologic study. A case-control study was designed, including 219 cases, 196 hospital-controls and 794 population controls. The collected information concerned profession, habits, behaviour (smoking, alcohol and coffee drinking), places of living, since childhood. The study confirms the role of tobacco, with a highly significant dose-effect, for total consumption, daily dose, and duration of consumption (p < 10(-4)). The classical risk of coffee is confirmed, but it seems not to be due to quantity of caffeine, but to the mouldered form of coffee. As far as alcohol is concerned, the sole risk is due to anisis beverages. When one considers the role of either tobacco, or coffee, or alcohol, the risk is strongly increased (p < 0.02) when exposure begins very early in life (childhood or teen age). But the effect does not depend on the beginning-of-exposure age, when the latter is posterior to teen age (p > 0.95). One may indeed think that the carcinogenic action of these factors concerns mainly the induction phase of the disease. Finally, when place of birth and place of living were considered, a North to South increasing effect was strongly suggested by the study.

This paper analyses 14 epidemiologic investigations (published from January 1980 to September 1991) about the relationship between urban air pollution and mortality. Air pollution indicators and mortality indicators are examined. Methods to analyse the relationships between these two kinds of indicators are classified according as they bring "qualitative information" trying to answer the question: "is there any relationship between air pollution and mortality?" or according as they try to quantify this relationship. Results are presented by author. Confounding factors and means to take them into account are described. This paper ends by a discussion about interest and limits of these studies. It emphasizes the importance of the collaboration between metrologists of urban air pollution and epidemiologists.

A random sample of 4-5 years old children born in the same year was taken from the infant schools of the Herault (France) and examined by pediatricians during a systematic check carried out by the Mother and Child Protection Department of the Health Service. This gave and estimation of the prevalence of the most widespread health problems: language, motricity, eyesight, hearing, obesity and asthma. Differences according to social and familial factors were found for language and motricity problems, as well as for access to preventive care.

A case-control investigation about bladder cancer was carried out in Herault department with 219 incident cases from January 1987 to May 1989 and two control groups: 196 hospital controls randomized from hospital admission lists and 794 population controls randomized from census data. According to the comparison for those two groups, there are few socio-demographic differences; but hospital controls are more exposed to smoking, coffee, alcohol, artificial sweetners. So, the odds ratios with those hospital controls are under-estimated. We can evaluate the resulting biais.

The main reason for using low molecular weight heparin (LMWH) is its capacity to keep the antithrombotic effect of standard non-fractioned heparin (NFH) while reducing its hemorrhagic power. Various studies comparing LMWH to NFH gave contradictory results, so we carried out a meta-analysis of randomized trials comparing these two treatments in prevention of deep-vein thrombosis (DVT) (and in prevention of deep-vein thrombosis or pulmonary embolism). From a selection of ten trials we could not show any significant difference in the DVT rates, as well as for the whole of surgical indications as for the subgroups of abdominal and orthopedic surgery. The weighted global difference between the DVT rates is so low that, in spite of the use of meta-analysis, the power is clearly insufficient. The hemorrhagic risk is not statistically reduced as well for the whole of surgical indications as for the subgroups.

The diagnosis of reactive arthritis requires the identification of a trigger infection. Since 1984 we have carried out a series of serological tests that we have called "serology of reactive arthritis": they aim at detecting antibodies against the most common infectious agents in this particular pathology. This serology is essentially based on the complement-fixation test. Here we report the results obtained over a period of two years, comparing them with clinical and biological data: 168 cases have been studied. They include to two groups of patients: group A reassembling seronegative spondylarthropathies and including reactive arthritis (N = 104), and group B with patients suffering from a typical rheumatic affection usually having no relation to spondylarthropathies (N = 64). We propose for each antigen a level of positivity from which the presence of antibodies can be taken into consideration as part of the diagnosis. With reference to these levels we have obtained a significant relationship to recent antecedents (genito-urinary and intestinal), to the presence of IgM circulating immune complexes and to the precocity of the serological tests. The contribution of this type of serology to the recognition of reactive arthritis has been studied together with the other diagnosis factors of the diseases. We have been able to show significant rates of antibodies in more than 50% of the cases. The negative results and limits of this serodiagnosis are discussed.

Cheiroarthropathy is quite frequent in diabetics, but is only really specific at stage III, which is the most characteristic form. It is all the more frequent as the diabetes is old, but remains unrelated to sex, age and type of diabetes. The stiffening of the joint readily extends to other joints. The patients are moderately alerted in the absence of other associated pathologies: trigger finger, Dupuytren's disease, carpal tunnel syndrome. All these manifestations form the "diabetic hand", of which cheiroarthropathy is only one component. The need for an accurate analysis with the purpose of appropriate treatments, should be emphasized. The angiologic and histopathological study of patients with stage III cheiroarthropathy, enables us to demonstrate moderate abnormalities of the microcirculation, which are quite different from those encountered in sclerodermia. The etiopathogenesis of cheiroarthropathy remains mysterious and is probably related to an alteration of the collagen metabolism. One of the most interesting component is the association between cheiroarthropathy and the micro-angiopathic complications of diabetes mellitus: cheiroarthropathy being the indicator of such diabetes.