Claire Segala

Short-Term Effects of Low-Level Winter Pollution on Respiratory Health of Asthmatic Adults

We studied the short-term effects of Paris winter air pollution (i.e., sulfur dioxide, Black Smoke, suspended particulates with an aerodynamic diameter close to 10 microm, and nitrogen dioxide) in 40 nonsmoking mild to moderate asthmatics (52% male; mean age = 46 y; 90% treated with inhaled steroids). During a 6-mo period, subjects recorded asthma symptoms and three daily peak expiratory flow measurements. Statistical analysis (i.e., generalized estimating equation models that accounted for autocorrelation of responses, weather data, and time trends) revealed consistent and significant associations between the pollutants and asthma attacks and symptoms in the entire study group, especially in the subgroup of individuals who took inhaled beta2 agonists as needed. Pollutants correlated negatively with morning peak expiratory flow in the subgroup that took inhaled beta2 agonists as needed, and they correlated positively with daily variability in asthmatics who received regularly scheduled inhaled beta2 agonists. The effects lingered several days after exposure occurred. Low-level pollution has consistent measurable effects on nonsmoking adults who have well-treated mild or moderate asthma.

Tumor progression and oxidant-antioxidant status

Severity of prognosis factors in breast cancer cases was found to be associated with an increase in plasma vitamin E and a decrease in plasma malondialdehyde (peroxidability index). The first aim of this study was to determine whether this association is also present in other cancers. Measurements were taken before therapy on 129 patients with various carcinomas. Cholesterol was also investigated, as vitamin E is closely related to this analyte. Patients were classified by tumor size (T < or = 5 cm and T > 5 cm) and by invasion status, assessed by the presence of nodes and/or metastasis. The vitamin E/total cholesterol concentration ratio was higher and the cholesterol and malondialdehyde concentrations were significantly lower in the plasma of patients with large tumors or in whom nodes and/or metastasis were present, whatever the site. The multivariate analysis performed to measure the association of these analyte concentrations with tumor progression showed that the presence of nodes and/or metastases was inversely associated with a low vitamin E/total cholesterol ratio (OR, 0.5; CI, 0.3-1.1) and, directly associated with low plasma concentrations of cholesterol and malondialdehyde (OR, 3.0; CI, 1.3-6.8 and OR, 2.8; CI, 1.2-6.7 respectively). The same types of associations were identified with large tumors, but were less strong. Together these findings supported an alteration of lipid parameters related to the oxidant-antioxidant status in cancer patients. This alteration appears to be associated with tumor growth and progression in patients with various cancer sites.

Nonlinear short-term effects of airborne Poaceae levels on hay fever symptoms.

effects reporting system in countries using FFP-MB might also have played a role. Finally, a possible bias concerning the rate of declaration could be related to the clinician awareness of a possible increased rate of allergic reactions with FFP-MB following the prospective survey decided by Agence française de s ecurit e sanitaire des produits de sant e. However, one should notice that this increased rate of allergy reports has been rapidly detected before the active survey. Although the mechanism of this increased risk of allergic reaction remains to be elucidated, our results are a strong incentive for a thorough reevaluation of the benefit-to-risk ratio of pathogen reduction using MB.

Air pollution, passive smoking, and respiratory symptoms in adults.

Abstract We studied the independent role of air pollution and passive smoking on respiratory symptoms and group of symptoms by following 46 adult nonsmokers for 14 wk. Outcomes included the incidence of 15 symptoms. After adjustment for passive smoking, clear rhinorrhea and cough were positively related to nitrogen dioxide (NO2), particles (PM10), and black smoke (BS); whereas headache was positively related to BS. Sneezing, sore throat, and cough were independently positively related to passive smoking. After adjustment for passive smoking, the occurrence of groups of symptoms and of the “sore throat group” were related to three pollutants. The occurrence of the “possible infection group” was positively related to BS. The occurrence of every group of symptoms was independently related to passive smoking. In conclusion, the prevailing levels of air pollution and passive smoking had independent effects on symptoms and groups of symptoms.

Effects of Airborne Birch Pollen Levels on Clinical Symptoms of Seasonal Allergic Rhinoconjunctivitis

Background: Most panel studies focusing on rhinitis and conjunctivitis symptoms and birch pollen have been performed on a linear basis and have not included air pollution and meteorological variables as potential confounders. The objective of this panel study was to assess the relationship between symptoms of seasonal allergic rhinoconjunctivitis and daily airborne birch pollen concentrations, checking with adequate statistical tools the shapes of concentration-response curves and controlling for confounders. Methods: The severity of rhinitis, conjunctivitis, and bronchial symptoms was recorded daily in March and April 2010 (3,311 person-days) in 61 seasonal allergic rhinoconjunctivitis patients sensitized to birch. Data were analyzed with generalized additive and generalized estimating equation models to quantify the effects of birch pollens. Results: The relationship between birch pollen and the percentage of patients with nasal, ocular and bronchial symptoms was linear until birch daily average concentrations of, respectively, 110, 70, and 70 grains/m3; it reached a plateau thereafter. For an increase of 10 grains/m3, the OR (95% CI) for nasal, ocular, and bronchial symptoms were, respectively, 1.07 (1.03-1.12), 1.17 (1.08-1.27), and 1.12 (1.03-1.21). At the beginning of the season, no nasal or ocular symptoms were observed below a threshold of 30 grains/m3. Conclusions: Adequate modeling regression shows that the clinical response to natural exposure to birch pollen in sensitized patients varies during Betula pollen season, with a threshold at the beginning of the season, while over the whole season the relationship is linear for nasal, ocular, and bronchial symptoms up to a saturation point, followed by a plateau.

A New Air Quality Perception Scale for Global Assessment of Air Pollution Health Effects

Despite improvements in air quality in developed countries, air pollution remains a major public health issue. To fully assess the health impact, we must consider that air pollution exposure has both physical and psychological effects; this latter dimension, less documented, is more difficult to measure and subjective indicators constitute an appropriate alternative. In this context, this work presents the methodological development of a new scale to measure the perception of air quality, useful as an exposure or risk appraisal metric in public health contexts. On the basis of the responses from 2,522 subjects in eight French cities, psychometric methods are used to construct the scale from 22 items that assess risk perception (anxiety about health and quality of life) and the extent to which air pollution is a nuisance (sensorial perception and symptoms). The scale is robust, reproducible, and discriminates between subpopulations more susceptible to poor air pollution perception. The individual risk factors of poor air pollution perception are coherent with those findings in the risk perception literature. Perception of air pollution by the general public is a key issue in the development of comprehensive risk assessment studies as well as in air pollution risk management and policy. This study offers a useful new tool to measure such efforts and to help set priorities for air quality improvements in combination with air quality measurements.

Trends in asthma-induced mortality in france from 1970–1990

OBJECTIVE The object of this research was to study the evolution of asthma-induced mortality in France from 1970-90 in the whole population and by age group. DESIGN Data from the French National Institute of Health and Medical Research (INSERM) and the population groups established by the French National Institute of Statistics and Economic Studies (INSEE) were used. The study was carried out on age-specific, crude and age-adjusted rates. RESULTS In the general population, a drop in the age-adjusted rates can be observed from 1970-80 in men and only until 1975 in women, followed by an increase until 1986 and then another drop. The rates among women have become closer to those in men. Among those aged 5-34, a clear increase is apparent in the age-adjusted rates for both sexes, in particular in the groups aged 15-24 and 25-34. In the older age groups, this increase involves only men aged 55-64 and women from 65 years onward. CONCLUSION It is highly unlikely that the variations observed can be explained by biases, and the increase seems therefore to be real, particularly in women and in those aged 5-34.

Traffic-related air pollution and the onset of myocardial infarction: disclosing benzene as a trigger? A small-area case-crossover study.

Background and Objectives Exposure to traffic is an established risk factor for the triggering of myocardial infarction (MI). Particulate matter, mainly emitted by diesel vehicles, appears to be the most important stressor. However, the possible influence of benzene from gasoline-fueled cars has not been explored so far. Methods and Results We conducted a case-crossover study from 2,134 MI cases recorded by the local Coronary Heart Disease Registry (2000–2007) in the Strasbourg Metropolitan Area (France). Available individual data were age, gender, previous history of ischemic heart disease and address of residence at the time of the event. Nitrogen dioxide, particles of median aerodynamic diameter <10 µm (PM10), ozone, carbon monoxide and benzene air concentrations were modeled on an hourly basis at the census block level over the study period using the deterministic ADMS-Urban air dispersion model. Model input data were emissions inventories, background pollution measurements, and meteorological data. We have found a positive, statistically significant association between concentrations of benzene and the onset of MI: per cent increase in risk for a 1 µg/m3 increase in benzene concentration in the previous 0, 0–1 and 1 day was 10.4 (95% confidence interval 3–18.2), 10.7 (2.7–19.2) and 7.2 (0.3–14.5), respectively. The associations between the other pollutants and outcome were much lower and in accordance with the literature. Conclusion We have observed that benzene in ambient air is strongly associated with the triggering of MI. This novel finding needs confirmation. If so, this would mean that not only diesel vehicles, the main particulate matter emitters, but also gasoline-fueled cars –main benzene emitters–, should be taken into account for public health action.

Aging and cancer: Plasma antioxidants and lipid peroxidation in young and aged breast cancer patients

The relationship between aging and cancer is complex because the intrication takes place at the cell, the organism and the environment levels. On the other hand, carcinogenesis is a multi-step process, and different mechanisms may be involved in each step. For example, oxidants and antioxidants may play a different role depending upon the phase considered. Tumors in older patients are generally described as slow growing. The difference in tumor aggressiveness between young and older patients is especially obvious in breast cancer patients. The age specificity of some breast risk factors suggests that breast cancer which has been diagnosed in an aged woman was induced late in her life. We address the question whether the characteristics of a senescent organism with regards to oxidant-antioxidant status could be causally related to the slow evolution of tumors in old patients.

Endotoxin concentration in poultry houses for laying hens kept in cages or in alternative housing systems

1. Endotoxins as components of organic dust may have adverse effects on the respiratory health of workers in poultry buildings. The move towards more welfare-friendly housing systems for layers may increase worker exposure to air contaminants due to the use of litter. 2. The endotoxin concentrations in the inhalable fraction of airborne dust (below 100 µm) from cage and alternative system houses (on-floor, free range and aviaries) were compared under both experimental and commercial conditions. 3. The endotoxin concentration was higher in experimental aviaries (median: 565 EU/m3, range: 362-1491 EU/m3) than in cage housing (98 EU/m3 (51-470)). 4. In field conditions, the endotoxin concentration in the air of 13 alternative houses was higher (35 to 3156 EU/m3) than in cage system buildings (n = 8, 78-576 EU/m3). It was correlated to the respirable dust concentration (fraction below 5 µm) and to the temperature inside the hen house but no seasonal variation was observed. 5. The present study emphasises that considerable worker exposure to endotoxins may occur in laying houses, especially in alternative systems.