Project Description

The roles of noise, placental function, green space, diet, physical activity, and socioeconomic status (FRONTIER)



In this study, the investigators will recruit pregnant women in Barcelona and assess the effects of in-utero exposure to traffic-related pollution on birth weight, fetal growth trajectories, and placental function for each pregnancy. The investigators will estimate exposure to several pollutants and transportation noise and evaluate the roles of socioeconomic status, green space, physical activity, diet, and stress.

Background. A substantial body of evidence has associated air pollution to impaired fetal growth; however, there are still substantial limitations in terms of applied exposure assessment methods, disentangling role of co-exposure such as noise, and evaluating the modifiers, mediators, and mitigators of this association. FRONTIER aims to provide a robust and comprehensive evaluation of the impact of maternal exposure to traffic-related air pollution on fetal growth. Towards this aim, it will (i) disentangle the effects of noise; (ii) identify the relevant window(s) of exposure; (iii) evaluate its modification by socioeconomic status, stress, and physical activity; (iv) elucidate the role of placental function as an underlying mechanism; and (v) explore the potential of green spaces to mitigate it.

Methods. FRONTIER will establish a new pregnancy cohort of 800 women in Barcelona, Spain. Fetal growth will be characterized by anthropometric measures at birth together with ultrasound-based trajectories of fetal development. Placental function will be evaluated using state-of-the-art Doppler ultrasound indicators. Hair cortisol levels at the third trimester will be used as an indicator of maternal stress during pregnancy. Time-activity patterns will be objectively characterized using a combination of smartphones and personal physical activity monitors. We will develop and validate an innovative exposure assessment framework integrating data on time-activity patterns with a hybrid modeling framework combining dispersion and land use regression models and campaigns of personal and home-outdoor air pollution monitoring to estimate maternal exposure level as well as inhaled dose of NO2, PM2.5, PM2.5 light absorption (a marker of tailpipe emissions), and PM2.5 Cu, Fe, and Zn contents (markers of non-tailpipe emissions) at the main microenvironments for pregnant women (home, workplace, and the commuting routes).

We will assess maternal exposure to noise by integrating measurements at participants’ bedroom window using noise monitors together with modeled microenvironmental levels of noise and data on noise sensitivity, annoyance, and protections against noise. We will apply detailed information on different characteristics of each tree canopy in our study region together with a high-resolution remote-sensing map of greenness to separately characterize the canopy and greenness surrounding maternal residential address. We will develop single- and multi-pollutant models to evaluate the impact of air pollution exposure and inhaled dose on fetal growth.

Results & Conclusions. FRONTIER will generate vigorous evidence base as well as practical information for implementing finely-targeted regulations and mitigation actions to tackle effects of air pollution on fetal growth.

Financing entity: Health Effects Institute (HEI)
Duration from 01/03/2018 to 28/02/2022
Subsidy amount: 999.998 $
Researcher responsible for CSIC: XAVIER QUEROL and TERESA MORENO (CSIC 42.726 $)

Contact: Teresa Moreno, Xavier Querol