Jacques Lambrozo

Magnetic fields and pineal function in humans: evaluation of nocturnal acute exposure to extremely low frequency magnetic fields on serum melatonin and urinary 6-sulfatoxymelatonin circadian rhythms.

Exposure to a 50/60-Hz electromagnetic field can decrease the nocturnal production of melatonin in rodents. Melatonin is considered to be a marker of circadian rhythms, and abnormalities in its secretion are associated with clinical disorders, including fatigue, sleep disruption, mood swings, impaired performance, and depression, which are consequences of desynchronisation. Interestingly, some epidemiological studies have been reported finding most of these clinical disorders in individuals living or working in an environment exposed to electromagnetic fields. This experiment was designed to look for the possible effects of acute exposure (9 hours) to 50-Hz linearly polarized magnetic fields (10 mu T) on the pineal function. Thirty-two young men (20-30 years old) were divided into two groups (control group, i.e., sham-exposed: 16 subjects; exposed group: 16 subjects). All subjects participated in two 24-hour experiments to evaluate the effects of both continuous and intermittent exposure to linearly polarized magnetic fields. They were synchronized with a diurnal activity from 08:00 to 23:00 and nocturnal rest. The experiment lasted two months (mid-February to mid-April). The subjects were exposed to the magnetic fields (generated by three Helmholtz coils per bed) from 23:00 to 08:00, while lying down. Blood samples were collected during each session at 3-hour intervals from 11:00 to 20:00 and hourly from 22:00 to 08:00. Total urine was collected every 3 hours from 08:00 to 23:00 and once during the night, from 23:00 to 08:00. The levels of serum melatonin and its metabolite in urine (6-sulfatoxymelatonin) in exposed men did not differ significantly from those in control (sham-exposed) subjects. This study shows that nocturnal acute exposure to either continuous or intermittent 50-Hz linearly polarized magnetic fields of 10 mu T does not affect melatonin secretion in humans.

Assessment of the effects of nocturnal exposure to 50-Hz magnetic fields on the human circadian system. A comprehensive study of biochemical variables.

The proposed laboratory investigation was designed to evaluate the effects of acute exposure to both continuous and intermittent magnetic fields (MFs) (50 Hz-10 microT) on the circadian rhythm of clinical chemistry variables in humans: electrolytes (magnesium, calcium, phosphorus, sodium, potassium, and chloride), enzymes (amylase, lipase, aldolase, gamma glutamyl-transferase [GGT], lactate dehydrogenase [LDH], aspartate aminotransferase [ASAT], and alkaline phosphatase [ALP]), lipids (cholesterol, high-density lipoprotein [HDL], apolipoprotein A1 [ApoA1], and ApoB), proteins (total proteins and albumin), nitrogen substances (uric acid, urea, and creatinine), iron, glycemia, and transferrin. Young volunteers (32 subjects; 16 exposed and 16 sham exposed) were selected according to the screening criteria. Each subject participated in two sessions held within a 4-week period. In the first session, one group of volunteers (16 subjects) was exposed to a continuous MF and then, in the second session, to an intermittent MF. The second group (16 subjects) served as a control for both sessions. At each session, blood samples were collected at 3 h intervals from 11:00 to 20:00 and hourly from 22:00 to 08:00. The results indicate that both continuous and intermittent 50-Hz linearly polarized MFs of 10 microT intensity have no effects on the circadian rhythms or on the levels of the variables studied here.

Repeated Nitrogen Dioxide Exposures and Eosinophilic Airway Inflammation in Asthmatics: A Randomized Crossover Study

Background: Nitrogen dioxide (NO2), a ubiquitous atmospheric pollutant, may enhance the asthmatic response to allergens through eosinophilic activation in the airways. However, the effect of NO2 on inflammation without allergen exposure is poorly studied. Objectives: We investigated whether repeated peaks of NO2, at various realistic concentrations, induce changes in airway inflammation in asthmatics. Methods: Nineteen nonsmokers with asthma were exposed at rest in a double-blind, crossover study, in randomized order, to 200 ppb NO2, 600 ppb NO2, or clean air once for 30 min on day 1 and twice for 30 min on day 2. The three series of exposures were separated by 2 weeks. The inflammatory response in sputum was measured 6 hr (day 1), 32 hr (day 2), and 48 hr (day 3) after the first exposure, and compared with baseline values measured twice 10–30 days before the first exposure. Results: Compared with baseline measurements, the percentage of eosinophils in sputum increased by 57% after exposure to 600 ppb NO2 (p = 0.003) but did not change significantly after exposure to 200 ppb. The slope of the association between the percentage of eosinophils and NO2 exposure level was significant (p = 0.04). Eosinophil cationic protein in sputum was highly correlated with eosinophil count and increased significantly after exposure to 600 ppb NO2 (p = 0.001). Lung function, which was assessed daily, was not affected by NO2 exposure. Conclusions: We observed that repeated peak exposures of NO2 performed without allergen exposure were associated with airway eosinophilic inflammation in asthmatics in a dose-related manner. Citation: Ezratty V, Guillossou G, Neukirch C, Dehoux M, Koscielny S, Bonay M, Cabanes PA, Samet JM, Mure P, Ropert L, Tokarek S, Lambrozo J, Aubier M. 2014. Repeated nitrogen dioxide exposures and eosinophilic airway inflammation in asthmatics: a randomized crossover study. Environ Health Perspect 122:850–855; http://dx.doi.org/10.1289/ehp.1307240

Methodology of a study on the French population exposure to 50 Hz magnetic fields

The characterisation of population exposure to a 50-Hz magnetic field (MF) is important for assessing health effects of electromagnetic fields. With the aim of estimating and characterising the exposure of the French population to 50-Hz MFs, two representative samples of the population were made. A random selection method based on the distribution of households in different regions of France was used. The samples were carried out starting from a random polling of telephone numbers of households (listed, unlisted fixed phones and cell phones only). A total of 95,362 telephone numbers were dialed to have 2148 volunteers (1060 children and 1088 adults). They all agreed to carrying an EMDEX II meter, measuring and recording MFs, and to filling out a timetable for a 24-hour period. In this article, the methodology of the sample selection and the collection of all necessary information for the realisation of this study are presented.

Exposure of children to extremely low frequency magnetic fields in France: Results of the EXPERS study

The assessment of magnetic field exposure in children is an important point in the context of epidemiological issues. EXPERS is the first study ever carried out measuring personal exposure to extremely low frequency magnetic fields at a national scale, involving 977 French children with 24 h personal measurements. Descriptive statistical analyses were performed for all the children, and only for children where no alarm clock was identified, as in some cases this requirement of the measurement protocol was not respected. The proportion of children with a 24 h arithmetic mean of ≥0.4 μT was 3.1% when considering all children and 0.8% when excluding alarm clocks. The alarm clocks were the main variable linked to the child exposure measurements. Magnetic field exposure increased when the home was located close to a high voltage power line. However, none of the 0.8% of children living at <125 m to a 225 kV line or <200 m to a 400 kV overhead line had a personal exposure of >0.4 μT. A multiple correspondence analysis showed the difficulty to build a statistical model predicting child exposure. The distribution of child personal exposure was significantly different from the distribution of exposure during sleep, questioning the exposure assessment in some epidemiological studies.

Long-term (up to 20 years) effects of 50-Hz magnetic field exposure on immune system and hematological parameters in healthy men

OBJECTIVES The relationship between exposure to 50-Hz magnetic fields and human health is of increasing interest since associations have been found in brain cancer in adults and childhood leukemia. In this study we investigate the possible chronic (up to 20 years) effects of exposure to magnetic fields in humans. DESIGN AND METHODS We examined the nocturnal profiles of red blood cells, hemoglobin, hematocrit, platelets, mean platelet volume, total white blood cells, lymphocytes, monocytes, eosinophils, basophils, neutrophils, Ig (Immunoglobulin) A, IgM, IgG, CD (cluster of differentiation) 3, CD4, CD8, natural killer cells, B cells, total CD28, CD8+ CD28+, activated T cells, interleukin (IL)-2, IL-6, and IL-2 receptor, in 15 men exposed chronically and daily for a period of 1-20 years, in the workplace and at home, to a 50-Hz magnetic field. The weekly geometric mean of individual exposures ranged from 0.1 to 2.6 μT. The results are compared to those of 15 unexposed men age-matched, with the same synchronization and physical activity that served as controls (individual exposures ranged from 0.004 to 0.092 μT). Blood samples were taken hourly from 20:00 h to 08:00 h. RESULTS Exposure over a long period and on a daily basis to magnetic fields resulted in no changes in the levels or patterns of hematological and immune system variables. CONCLUSIONS Our data show that a long-term exposure to 50-Hz magnetic fields does not affect the hematological and immune system functions or their profile in healthy men, at least for the variables studied, and suggest that magnetic fields have no cumulative effects on these functions.

Magnetophospenes in humans exposed to ELF MF up to 50 mT, a threshold study

Although magnetophosphene perception is the most reliable reported effect on acute human neurophysiological responses to extremely low frequency (ELF) magnetic field (MF) exposure, current knowledge is based on small sample size, non-replicated experiments. In this study, we established MF levels triggering magnetophosphenes at 20, 50, 60 and 100 Hz in humans. Magnetophosphene perception and EEG were collected in 55 magnetic flux density conditions randomly delivered in each frequency group (2 experiments, total n=145). Results indicate that threshold values 1) need to be reported as a function of dB/dt instead of flux density, and 2) are frequency-dependent (higher sensitivity to lower frequencies). No clear trend was found in EEG data.

Fuel poverty in France: Adapting an English methodology to assess the health cost implications

Over five million households in France are estimated to be in fuel poverty and so possibly exposed to low indoor temperatures. Such exposure is a threat to health. Besides the individual’s suffering, negative health outcomes, ranging from mild respiratory conditions to death, create demands on the health sector and costs to society. The health costs associated with energy inefficient dwellings have been calculated in England using a method based on the Housing Health & Safety Rating System (HHSRS); a health-based risk assessment system, adopted in 2006 as the prescribed statutory method for appraising housing conditions in England and Wales. The aim of this study was to use the English approach to estimate the health costs attributable to energy inefficient dwellings and energy vulnerability in France, and to analyse the cost benefits of thermal upgrades. This article details the methodology used to match the English and French housing energy efficiency assessment to provide the foundation necessary for the estimation of costs. This work has demonstrated that it is practicable to adapt the English HHSRS based approach, so that it can be used in another country such as France.

Energy and environmental intolerance: electromagnetic hypersensitivity, wind turbine syndrome. What is the reality?

Dans le contexte actuel des reflexions sur les moyens de production d’energie dans le cadre de la transition energetique, les questions d’intolerances environnementales idiopathiques s’invitent largement dans le debat, notamment l’electro-hypersensibilite attribuee aux champs electromagnetiques et le syndrome eolien incriminant les infrasons et sons de basses frequences emis par les eoliennes industrielles. Cet article tente de faire le point sur chacune de ces deux intolerances, en mettant en exergue leurs differences et leurs similarites. Si les sources incriminees sont differentes, en revanche les symptomes ressentis, variables et non specifiques d’une pathologie particuliere, sont tres similaires. Pour ces deux types de manifestations, aucune definition consensuelle du cas et aucun diagnostic medical n’ont ete etablis. Malgre l’absence de criteres diagnostiques objectifs, de nombreuses etudes ont recherche l’existence d’un lien potentiellement causal entre les symptomes et les facteurs environnementaux incrimines, visant a mettre en evidence un eventuel mecanisme sous-jacent plausible, qu’il soit de nature biologique ou psychologique. Pour l’electro-hypersensibilite, si la realite et parfois la gravite des symptomes ne font pas de doute, aucun lien causal avec les champs electromagnetiques n’est a ce jour demontre. Aucun mecanisme biologique n’apparait plausible. Pour le syndrome eolien, aucun effet sanitaire direct sur l’appareil auditif ou sur les autres organes imputable aux emissions sonores des eoliennes, dont les basses frequences et les infrasons, n’a pu etre demontre. La gene tangible frequemment evoquee est consideree le plus souvent liee a une perception negative des eoliennes en tant que telles. Pour l’un et l’autre syndrome, la piste d’un mecanisme psychologique a ete exploree, notamment la recherche d’un effet nocebo. En complement, des etudes commencent a investiguer le poids du collectif et les aspects sociologiques qui pourraient favoriser l’emergence de ces diverses formes d’intolerances. Enfin, en termes de prise en charge medicale, l’article s’interroge sur la place de ces intolerances environnementales emergentes par rapport aux manifestations somatomorphes bien connues notamment des medecins internistes.

Champs électriques et magnétiques de très basse fréquence : il est temps d’être raisonnable

« Le hasard ne favorise que les esprits prepares ». Louis PasteurL’amiante, l’encephalite spongiforme bovine,le diethylstilbestrol chez les femmes enceintes,l’hormone de croissance humaine : autant de crises de sante publique qui ont contribue a l’emergence du principe de precaution. A cette liste faut-ilajouter les champs electriques et magnetiques (CEM)produits par le courant electrique de frequence 50-60 Hz ?Lespremieres interrogations datent des annees soixante [...]