Alberto Gotti

Exposure to major volatile organic compounds and carbonyls in European indoor environments and associated health risk

This paper summarizes recent data on the occurrence of major organic compounds (benzene, toluene, xylenes, styrene, acetaldehyde, formaldehyde, naphthalene, limonene, α-pinene and ammonia, classified by the European Commissions INDEX strategy report as the priority pollutants to be regulated) and evaluates accordingly cancer and non-cancer risks posed by indoor exposure in dwellings and public buildings in European Union (EU) countries. The review process indicated that significant differences in indoor air quality exist within and among the countries where data were available, indicating corresponding differences in sources and emission strength of airborne chemicals, identified or not. Conservative exposure limits were not exceeded for non-carcinogenic effects, except for formaldehyde; for carcinogenic agents the estimated risks were up to three orders of magnitude higher than the one (10(-6)) proposed as acceptable by risk management bodies. However, the risk assessment evaluation process faces crucial difficulties, either due to the relative paucity of indoor air quality measurements in many EU countries, or by the lack of sampling consistency in the already existing studies, indicating the need for additional measurements of indoor air quality following a harmonized sampling and analytical protocol. Additionally, uncertainties embodied in the cancer potency factors and exposure limit values impose further difficulties in substance prioritization and risk management.

Exposure analysis of accidental release of mercury from compact fluorescent lamps (CFLs)

Mercury release after breakage of compact fluorescent lamps (CFLs) has recently become an issue of public health concern, especially in the case of early life infants. Preliminary, screening type calculations have indicated that there is potential for increased intake of mercury vapor by inhalation after breakage of a CFL. Several experimental and computational studies have shown that, when modeling the breakage of a CFL, the room space must be segregated into different zones, according to the potential of mercury vapor to accumulate in them after accidental release. In this study, a detailed two-zone model that captures the physicochemical processes that govern mercury vapor formation and dispersion in the indoor environment was developed. The mercury fate model was coupled to a population exposure model that accounts for age and gender-related differences in time-activity patterns, as well as country differences in body weight and age distribution. The parameters above are used to determine the intake through inhalation (gas phase and particles) and non-dietary ingestion (settled dust) for each age, gender group and ethnicity. Results showed that the critical period for intake covers the first 4h after the CFL breaks and that room air temperature significantly affects the intake rate. Indoor air concentration of mercury vapor may exceed toxicological thresholds of concern such as the acute Reference Exposure Limit (REL) for mercury vapor set by the Environmental Protection Agency of California. Ingestion intake through hand-to-mouth behavior is significant for infants and toddlers, counting for about 20% of the overall intake. Simple risk reduction measures including increased indoor ventilation followed by careful clean-up of the accident site, may limit dramatically the estimated health risk.

Bayesian algorithm implementation in a real time exposure assessment model on benzene with calculation of associated cancer risks.

The objective of the current study was the development of a reliable modeling platform to calculate in real time the personal exposure and the associated health risk for filling station employees evaluating current environmental parameters (traffic, meteorological and amount of fuel traded) determined by the appropriate sensor network. A set of Artificial Neural Networks (ANNs) was developed to predict benzene exposure pattern for the filling station employees. Furthermore, a Physiology Based Pharmaco-Kinetic (PBPK) risk assessment model was developed in order to calculate the lifetime probability distribution of leukemia to the employees, fed by data obtained by the ANN model. Bayesian algorithm was involved in crucial points of both model sub compartments. The application was evaluated in two filling stations (one urban and one rural). Among several algorithms available for the development of the ANN exposure model, Bayesian regularization provided the best results and seemed to be a promising technique for prediction of the exposure pattern of that occupational population group. On assessing the estimated leukemia risk under the scope of providing a distribution curve based on the exposure levels and the different susceptibility of the population, the Bayesian algorithm was a prerequisite of the Monte Carlo approach, which is integrated in the PBPK-based risk model. In conclusion, the modeling system described herein is capable of exploiting the information collected by the environmental sensors in order to estimate in real time the personal exposure and the resulting health risk for employees of gasoline filling stations.

Reflections on new directions for risk assessment of environmental chemical mixtures

Currently risk assessment of chemicals tackles them as single substances affecting individual health endpoints. In reality, human exposure occurs to mixtures of chemicals, as they are present in the environment and consumer products. Combining the information from environmental fate analysis, epidemiological data and toxicokinetic/dynamic models helps estimate internal exposure. Coupling these data with gene and protein expression profiles as signatures of exposure to classes of toxicants to derive biologically-based dose-response estimates may open the way towards adopting a biological connectivity approach to risk assessment. This work gives examples of applications of this approach on combined exposure to mixtures of volatile organic chemicals and estimation of body burden from chronic exposure to mixtures of chemicals and of the associated health risk. Conclusions are drawn as to the future scientific developments that will meet the requirements of integrated health risk assessment to protect public health from environmental and consumption-related stressors.

How Sensors Might Help Define the External Exposome

The advent of the exposome concept, the advancement of mobile technology, sensors, and the “internet of things” bring exciting opportunities to exposure science. Smartphone apps, wireless devices, the downsizing of monitoring technologies, along with lower costs for such equipment makes it possible for various aspects of exposure to be measured more easily and frequently. We discuss possibilities and lay out several criteria for using smart technologies for external exposome studies. Smart technologies are evolving quickly, and while they provide great promise for advancing exposure science, many are still in developmental stages and their use in epidemiology and risk studies must be carefully considered. The most useable technologies for exposure studies at this time relate to gathering exposure-factor data, such as location and activities. Development of some environmental sensors (e.g., for some air pollutants, noise, UV) is moving towards making the use of these more reliable and accessible to research studies. The possibility of accessing such an unprecedented amount of personal data also comes with various limitations and challenges, which are discussed. The advantage of improving the collection of long term exposure factor data is that this can be combined with more “traditional” measurement data to model exposures to numerous environmental factors.

Integrated exposure for risk assessment in indoor environments based on a review of concentration data on airborne chemical pollutants in domestic environments in Europe

This review set out to identify data sets for airborne chemical pollutants measured in domestic dwellings within European Union (EU) countries from the literature published during 1995–2010. A total of 74 papers satisfied inclusion criteria, and from those papers data on country location, population sampled, sampling period, number of samples and summary statistics of concentrations measured were gathered. The chemical substances identified and included were grouped to aldehydes, radon, carbon dioxide (CO2), carbon monoxide (CO), nicotine, nitrogen dioxide (NO2), polycyclic aromatic hydrocarbons, volatile organic compounds and brominated flame retardants. The review showed that the availability of data between the EU countries is varying and more measured data are available for countries in northern Europe than in the southern parts. This review is part of the Integrated Exposure for Risk Assessment in Indoor Environments project which developed a full-chain modelling platform, incorporating tools and databases for indoor chemical source release, exposure and risk assessment with the ultimate aim of estimating the health impact of chemical exposures in the indoor environment.

Fusion of air pollution data in the region of Munich, Germany, by the ICAROS NET platform

The air quality in Munich is monitored by the measurement network of the Bavarian Agency for Environmental Protection. Additional information can be provided from retrievals of optical thickness and corresponding particle concentrations from satellite images in an area of approximately 100 km x 100 km (depending on the satellite sensor used). The satellite measures the optical thickness of the entire atmosphere, which has to be attributed mainly to the mixing layer. The mixing layer height is determined either by remote sensing, by radiosondes, or by numerical models of the boundary layer. The corrected optical thickness of the satellite images can be interpreted as the particle concentration in the mixing layer. Data from the ground-based monitoring network and from satellite retrievals are fused in the ICAROS NET platform. This platform is applied to supply additional information on the air quality in the Munich region and it is tested as well as evaluated during field campaigns in summer and winter. The adaptation to the Munich region covers the development of routines for the collection of data, for example from the measuring network, and the disposal of information, which were defined by the Bavarian agency for environmental protection. During measurement campaigns in and around Munich PM 10, PM 2.5 and PM 1.0 concentrations and mixing layer heights by remote sensing (SODAR, ceilometer, WTR) were determined. Temporal variations of the concentration, the spatial distribution (3 measurement locations) and concentration conditions for selected particle sizes are presented.

Human biomonitoring data analysis for metals in an Italian adolescents cohort: An exposome approach

ABSTRACT The first Italian human biomonitoring survey (PROBE – PROgramme for Biomonitoring general population Exposure) considered a reference population of adolescents, aged 13–15 years, living in urban and rural areas and investigated their exposure to metals. The study was expanded up to 453 adolescents living in the same areas of Latium Region (Italy) and blood samples were analyzed for 19 metals (As, Be, Cd, Co, Cr, Hg, Ir, Mn, Mo, Ni, Pb, Pd, Pt, Rh, Sb, Sn, Tl, V, and W) by sector field inductively coupled plasma mass spectrometry. The exposure assessment was contextualized following an exposome approach that considered several determinants related to the subjects, available environmental parameters and geo‐coding of residence address. To assess the influence of exposure determinants and modifiers on children biomarkers levels we used two independent methodologies. The first makes use of the so‐called Environment‐Wide Association Study (EWAS) methodology while the second was based on the application of a Generalized Liner Model (GLM) capturing co‐exposures to pairs of key determinants. Based on our analysis, Hg and As were positively associated with dietary pathways (primarily linked to fish and to a lesser extent to milk consumption) while Cr showed a more complex interaction between co‐exposure to different dietary pathways (milk and fish) coupled to proximity of residence to industrial activities. In addition to diet, socio‐economic status of the mother revealed robust statistical associations with Cd, Ni and W biomonitoring levels in the respective children. HighlightsThe levels of 19 metals in blood of adolescents (13–15 years) were monitored.Exposome‐wide association analysis was performed.Diet and land‐use type of residence address are key exposome determinants.Socio‐economic status of family determines exposure to selected metals.No health risk was found based on biomonitoring data.

Comparison of data fusion methods for satellite-assisted determination of PM10 ambient concentration

Our recent work has demonstrated the feasibility of using satellite-derived data to draw quantitative maps of particulate loading within the planetary boundary layer. Our method, when used in conjunction with atmospheric dispersion models and ground data, can provide a comprehensive estimate of tropospheric pollution from particulate matter. Information filtering techniques are used to reduce the error of the information fusion algorithm and, consequently, produce the best possible estimate of tropospheric aerosol. Two data filtering methods have been used and their effectiveness with regard to overall error reduction is determined in this work. The first one is based on a weight scheme to take into account an empirical estimate of local error and/or uncertainty in input data. The second uses a modified Kalman filter for error reduction. The effectiveness of each of the filtering techniques depends on factors such as relative error variance across the computational domain, and precision of model input, i.e. on the accuracy of the ground emissions inventory and the reliability of measured ambient aerosol concentrations. The ICAROS NET fusion method was applied in the greater area of Athens, Greece over several days of observation in order to assess conclusively the adequacy of the information fusion filters employed.

Monitoring of air pollution levels related to Charilaos Trikoupis Bridge

Charilaos Trikoupis bridge is the longest cable bridge in Europe that connects Western Greece with the rest of the country. In this study, six air pollution monitoring campaigns (including major regulated air pollutants) were carried out from 2013 to 2015 at both sides of the bridge, located in the urban areas of Rio and Antirrio respectively. Pollution data were statistically analyzed and air quality was characterized using US and European air quality indices. From the overall campaign, it was found that air pollution levels were below the respective regulatory thresholds, but once at the site of Antirrio (26.4 and 52.2μg/m3 for PM2.5 and ΡΜ10, respectively) during the 2nd winter period. Daily average PM10 and PM2.5 levels from two monitoring sites were well correlated to gaseous pollutant (CO, NO, NO2, NOx and SO2) levels, meteorological parameters and factor scores from Positive Matrix Factorization during the 3-year period. Moreover, the elemental composition of PM10 and PM2.5 was used for source apportionment. That analysis revealed that major emission sources were sulfates, mineral dust, biomass burning, sea salt, traffic and shipping emissions for PM10 and PM2.5, for both Rio and Antirrio. Seasonal variation indicates that sulfates, mineral dust and traffic emissions increased during the warm season of the year, while biomass burning become the dominant during the cold season. Overall, the contribution of the Charilaos Trikoupis bridge to the vicinity air pollution is very low. This is the result of the relatively low daily traffic volume (~10,000 vehicles per day), the respective traffic fleet composition (~81% of the traffic fleet are private vehicles) and the speed limit (80km/h) which does not favor traffic emissions. In addition, the strong and frequent winds further contribute to the rapid dispersion of the emitted pollutants.