Risk management policies and practices regarding radio frequency electromagnetic fields: results from a WHO survey

This study aims to describe current risk management practices and policies across the world in relation to personal exposures from devices emitting radiofrequency fields, environmental exposures from fixed installations and exposures in the work environment. Data from 86 countries representing all WHO regions were collected through a survey. The majority of countries (76.8 %) had set exposure limits for mobile devices, almost all (90.7 %) had set public exposure limits for fixed installations and 76.5 % had specified exposure limits for personnel in occupational settings. A number of other policies had been implemented at the national level, ranging from information provisions on how to reduce personal exposures and restrictions of usage for certain populations, such as children or pregnant women to prevention of access around base stations. This study suggests that countries with higher mobile subscriptions tend to have set radiofrequency exposure limits for mobile devices and to have provisions on exposure measurements about fixed installation

Exposure of hairdressing apprentices to airborne hazardous substances

BACKGROUND: Few studies have investigated exposure of hairdressing apprentices to airborne irritants. This study describes exposure levels of apprentices to chemical products used in hairdressing salons in relation with their activity. METHODS: Following a two stages study design, a group of 300 students completed a questionnaire on their work activities and environment. Among these, a group of 28 subjects volunteered to undergo personal exposure and workplace concentrations measurements over a work shift, during a cold and a hot season, with the agreement of the salon owners. Three chemical substances were studied (ammonia, hydrogen peroxide and persulfates) because they are respiratory tract irritants and because their concentrations could be quantified within a 5 to 8 hour shift period. RESULTS: Personal exposure values for H(2)O(2)and NH(3) (averages [standard deviations] are 0.05 [0.04] and 0.90 [0.76] mg.m(-3), respectively) were greater than workplace ambient air concentrations (corresponding values of 0.04 [0.03] and 0.68 [0.42] mg.m(-3)) for H(2)O(2 )and NH(3), with no significant seasonal variation. By contrast, workplace concentrations of persulfates (0.019 [0.018] mg.m(-3)) were greater than personal exposure (0.016 [0.021] mg.m(-3), a finding that is consistent with the fact that bleaching is more often undertaken by senior hairdressers. However, all exposure values were lower than the current TLV TWA values. This study also shows that over half of technical spaces where chemical substances used for dying, permanenting or bleaching are manipulated, have no ventilation system, and not even a door or a window opening outside. CONCLUSION: The study hairdressing salons, on average, were small, the most probable reason why occupational hygiene measures such as appropriate ventilation were too seldom implemented. As a consequence, young apprentices and senior hairdressers experience substantial exposure to known airways irritants

Multiple exposures to indoor contaminants: Derivation of benchmark doses and relative potency factors based on male reprotoxic effects

International audienceSemi-Volatile Organic Compounds (SVOCs) are commonly present in dwellings and several are suspected of having effects on male reproductive function mediated by an endocrine disruption mode of action. To improve knowledge of the health impact of these compounds, cumulative toxicity indicators are needed. This work derives Benchmark Doses (BMD) and Relative Potency Factors (RPF) for SVOCs acting on the male reproductive system through the same mode of action. We included SVOCs fulfilling the following conditions: detection frequency (>10%) in French dwellings, availability of data on the mechanism/mode of action for male reproductive toxicity, and availability of comparable dose-response relationships. Of 58 SVOCs selected, 18 induce a decrease in serum testosterone levels. Six have sufficient and comparable data to derive BMDs based on 10 or 50% of the response. The SVOCs inducing the largest decrease in serum testosterone concentration are: for 10%, bisphenol A (BMD10= 7.72E-07 mg/kg bw/d; RPF10= 7033679); for 50%, benzo[a]pyrene (BMD50= 0.030 mg/kg bw/d; RPF50= 1630), and the one inducing the smallest one is benzyl butyl phthalate (RPF10 and RPF50= 0.095). This approach encompasses contaminants from diverse chemical families acting through similar modes of action, and makes possible a cumulative risk assessment in indoor environments. The main limitation remains the lack of comparable toxicological data

Data analysis techniques: a tool for cumulative exposure assessment.

International audienceEveryone is subject to environmental exposures from various sources, with negative health impacts (air, water and soil contamination, noise, etc.or with positive effects (e.g. green space). Studies considering such complex environmental settings in a global manner are rare. We propose to use statistical factor and cluster analyses to create a composite exposure index with a data-driven approach, in view to assess the environmental burden experienced by populations. We illustrate this approach in a large French metropolitan area. The study was carried out in the Great Lyon area (France, 1.2 M inhabitants) at the census Block Group (BG) scale. We used as environmental indicators ambient air NO2 annual concentrations, noise levels and proximity to green spaces, to industrial plants, to polluted sites and to road traffic. They were synthesized using Multiple Factor Analysis (MFA), a data-driven technique without a priori modeling, followed by a Hierarchical Clustering to create BG classes. The first components of the MFA explained, respectively, 30, 14, 11 and 9% of the total variance. Clustering in five classes group: (1) a particular type of large BGs without population; (2) BGs of green residential areas, with less negative exposures than average; (3) BGs of residential areas near midtown; (4) BGs close to industries; and (5) midtown urban BGs, with higher negative exposures than average and less green spaces. Other numbers of classes were tested in order to assess a variety of clustering. We present an approach using statistical factor and cluster analyses techniques, which seem overlooked to assess cumulative exposure in complex environmental settings. Although it cannot be applied directly for risk or health effect assessment, the resulting index can help to identify hot spots of cumulative exposure, to prioritize urban policies or to compare the environmental burden across study areas in an epidemiological framework.Journal of Exposure Science and Environmental Epidemiology advance online publication, 24 September 2014; doi:10.1038/jes.2014.66

Concentration and determinants of molds and allergens in indoor air and house dust of French dwellings

International audienceMolds and allergens are common indoor biocontaminants. The aims of this study were to assess the concentrations of common molds in indoor air and floor dust and the concentrations of house dust mite, cat and dog allergens in mattress dust in French dwellings, and to assess predictors of these concentrations. A sample of 150 houses in Brittany (western France) was investigated. Airborne Cladosporium and Penicillium were detected in more than 90% of the dwellings, Aspergillus in 46% and Alternaria in only 6% of the housings. Regarding floor dust samples, Cladosporium and Penicillium were detected in 92 and 80% of the housings respectively, Aspergillus in 49% and Alternaria in 14%. House dust mite allergens Der p1 and Der f1 were detected in 90% and 77% of the mattress dust samples respectively and Can f1 and Fel d1 in 37% and 89% of the homes. Airborne and dustborne mold concentrations, although not statistically correlated (except for Aspergillus) shared most of their predictors. Multivariate linear models for mold levels, explaining up to 62% of the variability, showed an influence of the season, of the age of the dwelling, of aeration habits, presence of pets, smoking, signals of dampness, temperature and relative humidity. Allergens in the dust of the mattress were strongly related to the presence of pets and cleaning practices of bedsheets, these factors accounting for 60% of the variability. This study highlights ubiquitous contamination by molds and underlines complex interaction between outdoor and indoor sources and factor

Early markers of airways inflammation and occupational asthma: Rationale, study design and follow-up rates among bakery, pastry and hairdressing apprentices

<p>Abstract</p> <p>Background</p> <p>Occupational asthma is a common type of asthma caused by a specific agent in the workplace. The basic alteration of occupational asthma is airways inflammation. Although most patients with occupational asthma are mature adults, there is evidence that airways inflammation starts soon after inception of exposure, including during apprenticeship. Airways hyper responsiveness to methacholine is a valid surrogate marker of airways inflammation, which has proved useful in occupational epidemiology. But it is time-consuming, requires active subject's cooperation and is not readily feasible. Other non-invasive and potentially more useful tests include the forced oscillation technique, measurement of fraction exhaled nitric oxide, and eosinophils count in nasal lavage fluid.</p> <p>Methods and design</p> <p>This study aims to investigate early development of airways inflammation and asthma-like symptoms in apprentice bakers, pastry-makers and hairdressers, three populations at risk of occupational asthma whose work-related exposures involve agents of different nature. The objectives are to (i) examine the performance of the non-invasive tests cited above in detecting early airways inflammation that might eventually develop into occupational asthma; and (ii) evaluate whether, and how, constitutional (e.g. atopy) and behavioural (e.g. smoking) risk factors for occupational asthma modulate the effects of allergenic and/or irritative substances involved in these occupations. This paper presents the study rationale and detailed protocol.</p> <p>Discussion</p> <p>Among 441 volunteers included at the first visit, 354 attended the fourth one. Drop outs were investigated and showed unrelated to the study outcome. Sample size and follow-up participation rates suggest that the data collected in this study will allow it to meet its objectives.</p

Bias in Estimating Multivariate and Univariate Diffusions

Published in Journal of Econometrics, 2011, https://doi.org/10.1016/j.jeconom.2010.12.006</p

Evaporative Gasoline Emissions and Asthma Symptoms

Attached garages are known to be associated with indoor air volatile organic compounds (VOCs). This study looked at indoor exposure to VOCs presumably from evaporative emissions of gasoline. Alaskan gasoline contains 5% benzene making benzene a marker for gasoline exposure. A survey of randomly chosen houses with attached garages was done in Anchorage Alaska to determine the exposure and assess respiratory health. Householders were asked to complete a health survey for each person and a household survey. They monitored indoor air in their primary living space for benzene, toluene, ethylbenzene and xylenes for one week using passive organic vapor monitoring badges. Benzene levels in homes ranged from undetectable to 58 parts per billion. The median benzene level in 509 homes tested was 2.96 ppb. Elevated benzene levels in the home were strongly associated with small engines and gasoline stored in the garage. High concentrations of benzene in gasoline increase indoor air levels of benzene in residences with attached garages exposing people to benzene at levels above ATSDR’s minimal risk level. Residents reported more severe symptoms of asthma in the homes with high gasoline exposure (16%) where benzene levels exceeded the 9 ppb