Corinne Mandin

Health ranking of ingested semi-volatile organic compounds in house dust: an application to France.

UNLABELLEDnPeople spend most of their time indoors. Dust settled in the home may be contaminated by semi-volatile organic compounds (SVOCs). Exposure to these compounds is of great concern, in particular for infants. Their number is large so arose the question of which ones should be selected for dust ingestion exposure assessment. This work proposes a health ranking of SVOCs ingested through settled dust. This ranking is based on the toxicity and contamination of SVOCs in dust. Data on compounds and contamination was retrieved from a bibliographic review. Where possible, toxicity data was retrieved from databases, otherwise it was calculated from raw data. One hundred and fifty-six SVOCs were selected, 66 of which were prioritized. Forty-two could not be prioritized because contamination data was below the limit of detection, and 48 could not be prioritized because there was no contamination or toxicity data. The top-ranked compounds were phthalates, pesticides, short-chain chlorinated paraffins, PBDEs, PFCs, organotins, PCBs, and PAHs. As most of these have reprotoxic and neurotoxic properties, an integrated multi-pollutants approach to exposure is required and simultaneous measurement methods should be developed.nnnPRACTICAL IMPLICATIONSnThe large number of compounds identified in settled dust in recent years should be considered for the assessment of exposure to dust ingestion. This work provides a health ranking of SVOCs ingested through settled dust. Most of the top-ranked compounds have reprotoxic and neurotoxic properties, and particular attention should, therefore, be paid to them in future studies.

Distributions of the particle/gas and dust/gas partition coefficients for seventy-two semi-volatile organic compounds in indoor environment.

Particle/gas and dust/gas partition coefficients (Kp and Kd) are two key parameters that address the partitioning of semi-volatile organic compounds (SVOCs) between gas-phase, airborne particles, and settled dust in indoor environment. A number of empirical equations to calculate the values of Kp and Kd have been reported in the literature. Therefore, the difficulty lies in the selection of a specific empirical equation in a given situation. In this study, we retrieved from the literature 38 empirical equations for calculating Kp and Kd values from the SVOC saturation vapor pressure and octanol/air partition coefficient. These values were calculated for 72 SVOCs: 9 phthalates, 9 polybrominated diphenyl ethers (PBDEs), 11 polychlorinated biphenyls (PCBs), 22 biocides, 14 polycyclic aromatic hydrocarbons (PAHs), 3 alkylphenols, 2 synthetic musks, tributylphosphate, and bisphenol A. The mean and median values of log10Kp or log10Kd for most SVOCs were of the same order of magnitude. The distribution of log10Kp values was fitted to either a normal distribution (for 27 SVOCs) or a log-normal distribution (for 45 SVOCs). This work provides a reference distribution of the log10Kp for 72 SVOCs, and its use may reduce the bias associated with the selection of a specific value or equation.

Cleaning practices and cleaning products in nurseries and schools: to what extent can they impact indoor air quality?

In the framework of a nationwide survey on indoor air quality conducted from September 2009 to June 2011 in 310 nurseries, kindergartens, and elementary schools in all regions of France, cleaning practices and products were described through an extensive questionnaire completed on-site by expert building inspectors. The questionnaire included the cleaning frequencies and periods, cleaning techniques, whether windows were open during cleaning, and the commercial names of the products used. Analysis of the questionnaire responses showed that cleaning was generally performed daily for furniture and floors. It was performed mostly in the evening with wet mopping and with one or more windows open. Five hundred eighty-four different cleaning products were listed, among which 218 safety data sheets (SDSs) were available and analyzed. One hundred fifty-two chemical substances were identified in the SDSs. The typical substances in cleaning products included alcohols, chlorides, terpenes, aldehydes, and ethers; more than half of them are irritants. Two endocrine disruptors, 2-phenylphenol and Galaxolide, were identified in two cleaning products used every day to clean the floors, in seven kindergartens and in a nursery respectively. Eleven reactive substances containing C=C double bonds, mostly terpenes, were identified in a wide variety of cleaning products.

Indoor residential exposure to semivolatile organic compounds in France

Multiple chemicals are emitted in residential accommodation. Aggregate Daily Doses (ADD) (ng/kg-bw/d) were estimated for 32 semivolatile organic compounds (SVOCs) of different chemical families that are frequently detected in French dwellings in both air and settled dust. Daily doses were determined using steady-state models for the population, categorized into 11 age groups covering birth to age 30. Three routes of exposure were taken into account: dust ingestion, inhalation (gaseous and particulate phases) and dermal contact with the gaseous phase of air. Contamination levels were preferentially retrieved from large, nationwide representative datasets. A two-dimensional probabilistic approach was used to assess parametric uncertainty and identify the most influential factors. For children aged 2 to 3years, ADD estimates spanned orders of magnitude, with median values ranging from 8.7pg/kg-bw/d for 2,2,3,4,4-pentabromodiphenylether (BDE 85) to 1.3μg/kg-bw/d for di-isobutyl phthalate (DiBP). Inhalation, ingestion and dermal pathway contributed at varying levels, and depending on compound, air was the dominant medium for 28 of the 32 compounds (either by inhalation or dermal contact). Indoor exposure estimate variance was mainly driven by indoor contamination variability, and secondarily by uncertainty in physical and chemical parameters. These findings lend support to the call for cumulative risk assessment of indoor SVOCs.

Bioaccessibility and bioavailability of environmental semi-volatile organic compounds via inhalation: A review of methods and models

Semi-volatile organic compounds (SVOCs) present in indoor environments are known to cause adverse health effects through multiple routes of exposure. To assess the aggregate exposure, the bioaccessibility and bioavailability of SVOCs need to be determined. In this review, we discussed measurements of the bioaccessibility and bioavailability of SVOCs after inhalation. Published literature related to this issue is available for 2,3,7,8-tetrachlorodibenzo-p-dioxin and a few polycyclic aromatic hydrocarbons, such as benzo[a]pyrene and phenanthrene. Then, we reviewed common modeling approaches for the characterization of the gas- and particle-phase partitioning of SVOCs during inhalation. The models are based on mass transfer mechanisms as well as the structure of the respiratory system, using common computational techniques, such as computational fluid dynamics. However, the existing models are restricted to special conditions and cannot predict SVOC bioaccessibility and bioavailability in the whole respiratory system. The present review notes two main challenges for the estimation of SVOC bioaccessibility and bioavailability via inhalation in humans. First, in vitro and in vivo methods need to be developed and validated for a wide range of SVOCs. The in vitro methods should be validated with in vivo tests to evaluate human exposures to SVOCs in airborne particles. Second, modeling approaches for SVOCs need to consider the whole respiratory system. Alterations of the respiratory cycle period and human biological variability may be considered in future studies.

Influence of indoor environmental factors on mass transfer parameters and concentrations of semi-volatile organic compounds

Semi-volatile organic compounds (SVOCs) in indoor environments can partition among the gas phase, airborne particles, settled dust, and available surfaces. The mass transfer parameters of SVOCs, such as the mass transfer coefficient and the partition coefficient, are influenced by indoor environmental factors. Subsequently, indoor SVOC concentrations and thus occupant exposure can vary depending on environmental factors. In this review, the influence of six environmental factors, i.e., indoor temperature, humidity, ventilation, airborne particle concentration, source loading factor, and reactive chemistry, on the mass transfer parameters and indoor concentrations of SVOCs was analyzed and tentatively quantified. The results show that all mass transfer parameters vary depending on environmental factors. These variations are mostly characterized by empirical equations, particularly for humidity. Theoretical calculations of these parameters based on mass transfer mechanisms are available only for the emission of SVOCs from source surfaces when airborne particles are not present. All mass transfer parameters depend on the temperature. Humidity influences the partition of SVOCs among different phases and is associated with phthalate hydrolysis. Ventilation has a combined effect with the airborne particle concentration on SVOC emission and their mass transfer among different phases. Indoor chemical reactions can produce or eliminate SVOCs slowly. To better model the dynamic SVOC concentration indoors, the present review suggests studying the combined effect of environmental factors in real indoor environments. Moreover, interactions between indoor environmental factors and human activities and their influence on SVOC mass transfer processes should be considered.

Socio-economic costs of indoor air pollution: A tentative estimation for some pollutants of health interest in France

An evaluation of the socio-economic costs of indoor air pollution can facilitate the development of appropriate public policies. For the first time in France, such an evaluation was conducted for six selected pollutants: benzene, trichloroethylene, radon, carbon monoxide, particles (PM2.5 fraction), and environmental tobacco smoke (ETS). The health impacts of indoor exposure were either already available in published works or were calculated. For these calculations, two approaches were followed depending on the available data: the first followed the principles of quantitative health risk assessment, and the second was based on concepts and methods related to the health impact assessment. For both approaches, toxicological data and indoor concentrations related to each target pollutant were used. External costs resulting from mortality, morbidity (life quality loss) and production losses attributable to these health impacts were assessed. In addition, the monetary costs for the public were determined. Indoor pollution associated with the selected pollutants was estimated to have cost approximately €20 billion in France in 2004. Particles contributed the most to the total cost (75%), followed by radon. Premature death and the costs of the quality of life loss accounted for approximately 90% of the total cost. Despite the use of different methods and data, similar evaluations previously conducted in other countries yielded figures within the same order of magnitude.

Indoor air quality in energy-efficient dwellings: Levels and sources of pollutants

Worldwide, public policies are promoting energy-efficient buildings and accelerating the thermal renovation of existing buildings. The effects of these changes on the indoor air quality (IAQ) in these buildings remain insufficiently understood. In this context, a field study was conducted in 72 energy-efficient dwellings to describe the pollutants known to be associated with health concerns. Measured parameters included the concentrations of 19 volatile organic compounds and aldehydes, nitrogen dioxide, particulate matter (PM2.5 ), radon, temperature, and relative humidity. The air stuffiness index and night-time air exchange rate were calculated from the monitored carbon dioxide (CO2 ) concentrations. Indoor and outdoor measurements were performed at each dwelling during 1xa0week in each of the two following seasons: heating and non-heating. Moreover, questionnaires were completed by the occupants to characterize the building, equipment, household, and occupants habits. Perspective on our results was provided by previous measurements made in low-energy European dwellings. Statistical comparisons with the French housing stock and a pilot study showed higher concentrations of terpenes, that is, alpha-pinene and limonene, and hexaldehyde in our study than in previous studies. Alpha-pinene and hexaldehyde are emitted by wood or wood-based products used for the construction, insulation, decoration, and furnishings of the dwellings, whereas limonene is more associated with discontinuous sources related to human activities.

Chemical-by-chemical and cumulative risk assessment of residential indoor exposure to semivolatile organic compounds in France

BACKGROUNDnThe toxic effects of environmental exposure to chemicals are increasingly being studied and confirmed, notably for semivolatile organic compounds (SVOCs). These are found in many products and housing materials, from which they are emitted to indoor air, settled dust and other surfaces.nnnOBJECTIVESnThe objective of this work is to assess the human health risk posed by residential indoor exposure to 32 SVOCs, assessed in previous nationwide studies.nnnMETHODSnA chemical-by-chemical risk assessment, using a hazard quotient (HQ) or excess risk (ER) method, was supplemented by a cumulative risk assessment (CRA). For CRA, a hazard index (HI) method, as well as higher tier approaches using relative potency factors (RPFs) or toxic equivalency factors (TEFs) were used for the following endpoints: neurotoxicity, reproductive toxicity, genotoxicity and immunotoxicity.nnnRESULTSnHQs were above 1 for 50% of French children from birth to 2u202fyears for BDE 47, and for 5% of children for lindane and dibutyl phthalate (DBP). Corresponding hazards are reprotoxic for BDE 47 and DBP, and immunotoxic for lindane. The CRA approach provided additional information of reprotoxic risks (HIu202f>u202f1) that may occur for 95% of children and for 5% of the offspring for pregnant womens exposure. The SVOCs contributing most to these risks were PCB 101 and 118, BDE 47, and DBP. The higher tier CRA approaches showed that exposure to dwellings SVOC mixtures were of concern for 95% of children for neurotoxic compounds having effects linked with neuronal death. To a lesser extent, effects mediated by the aryl hydrocarbon receptor (AhR) or by a decrease in testosterone levels may concern 5% of children and adults. Lastly, unacceptable immunotoxic risk related to exposure to 8 indoor PCBs was also observed for 5% of children.nnnCONCLUSIONSnIn view of uncertainties related to compounds toxicity for humans, these results justify the implementation of preventive measures, as well as the production of more standardized and comprehensive toxicological data for some compounds.

Perceived indoor air quality and its relationship to air pollutants in French dwellings

Perception of indoor air quality (PIAQ) was evaluated in a nationwide survey of 567 French dwellings, and this survey was combined with measurements of gaseous and particulate matter (PM10 and PM2.5 ) indoor air pollutants and indoor climate parameters. The perception was assessed on a nine-grade scale by both the occupants of the dwellings and the inspectors who performed the measurements. The occupants perceived the air quality in their homes as more pleasant than the inspectors. The inspectors perceived the air quality as more unpleasant in dwellings in which the residents smoked indoors. Significant associations between PIAQ and indoor air pollutant concentrations were observed for both the inspectors and, to a lesser extent, the occupants. Introducing confounding parameters, such as building and personal characteristics, into a multivariate model suppressed most of the observed bivariate correlations and identified the tenure status of the occupants and their occupation as the parameters that most influenced their PIAQ. For the inspectors, perceived air quality was affected by the presence of smokers, the season, the type of ventilation, retrofitting, and the concentrations of acetaldehyde and acrolein.