Data collected

Environmental exposure

Urban Exposome

To measure the exposure to various air pollutants, the SEPAGES cohort used several tools:

  • MicroPEM sensors to measure exposure to PM2.5
  • Passive Passam sensors to measure exposure to NO2 and volatile organic compounds (benzene, toluene, ethylbenzene, and xylenes)
  • MicroAeth sensor, carried by a subset of participants to measure aerosol black carbon exposure
  • The ExpoApp app (developed by Atekena Solution) installed on mobile phones to record all geolocation data, which were then compared with air pollution maps produced by the association Air Rhône-Alpes (an association located in the Grenoble metropolitan area) that works on air quality and models pollution levels in the Rhône-Alpes region. Geolocation allows us to estimate exposure to other environmental factors, such as weather conditions and access to green spaces.
  • Actisleep, which provided information on physical activity and sleep

These miniaturized devices were worn continuously for one-week periods and allowed data to be collected on personal exposure to air pollution by measuring the exposure to both outdoor and indoor air.

Exposition urbaine

Chemical Exposome

Many chemical pollutants were assessed in biological samples collected during pregnancy and in the early years of life. These assessments allow us to estimate the exposure to chemical pollutants of the volunteers in the study. The pollutants measured to date are:

  • phenols: bisphenols (A, AF, B, S, F), triclosan, triclocarban, parabens (methyl, ethyl, butyl, propyl), benzophenone
  • phthalates
  • organophosphate pesticides
  • perfluorinated compounds

Health parameters

Growth data based on ultrasound data were collected during pregnancy. After delivery, growth data were collected during the two-month, one-year, and three-year follow-up examinations and through questionnaires administered regularly to parents.

Santé croissance foetale 1
Santé croissance foetale 2

Cardiac health was evaluated during clinical examinations. Parents submitted to an electrocardiogram and a blood pressure reading. For children, the blood pressure was taken at each follow-up visit of the cohort (two months, one year, and three years).

Santé cardiaque

These data were collected during clinical examinations. Parents underwent a lung function exam and were tested for skin allergies. A respiratory examination of the children was done six weeks after birth by measuring the Lung Clearance Index and at three years by using the forced oscillation technique. Children were tested for skin allergies at three years of age. Each year, parents filled out a questionnaire on their child’s respiratory health.

Santé respiratoire
Santé allergie

Child development data were collected annually through standardized questionnaires. At the age of two, a subset of the children was given eye-tracking tests at The Grenoble Alpes University BabyLab. At the age of three, all children were seen by a neuropsychologist who administered the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-IV).

Santé neuro-développement

In addition, the various co-factors were filled in through numerous questionnaires self-administered several times throughout the follow-up period. The questionnaires covered the topics of tobacco, housing, professional activity, pets, food, childcare, exposure to display screens, and child activities.

Biological samples

During pregnancy, the volunteers collected three urines per day for two to three weeks. At two months, one year, and three years, between one and two urine samples per day were collected from the children. At the Biological Resource Center of the Grenoble Alpes University Hospital, these urine samples were pooled to make daily or weekly samples. A daily pool consists of mixing together a small amount of urine from each sample collected on a given day to make a “day” sample. A weekly pool consists of mixing together a small amount of urine from each sample collected over the course of a given week to make a “week” sample. The week samples were assessed for chemical pollutants (phenols and phthalates).

Urinary collections

During pregnancy, maternal blood was collected at around 19 weeks of amenorrhea. The father’s blood was sampled at the time of inclusion in the study and the child’s blood at the time of birth (a drop of blood on Guthrie cards and cord blood) and at one and three years of age. The blood served to assess thyroid hormones, immunological parameters, or DNA methylation.

Blood collection

At delivery, five small pieces of placenta were removed by the maternity staff. The placenta provides data on such things as placental methylation.

Placenta sampling

Meconium, which corresponds to the child’s first stools, was collected at the maternity ward, following which the stool was collected by the parents at two months, one year, two years (for one subset of children), and three years. Some of the mothers also provided stool samples. The stools were used to study the intestinal microbiota. The gut microbiota are the microorganisms (nonpathogenic bacteria, viruses, parasites, and fungi) located mainly in the small intestine and colon.

Several hair samples were taken, first from the mother during pregnancy and at the time of delivery and then from the child at birth, two months, one year, three years, and five years. A hair sample was also taken from the father at the time of the inclusion visit. Among other things, hair samples can be used to assess steroid hormones.

Hair samples

Oral cells were collected from the child at one and three years of age, and nasal cells were collected at three years of age. Samples of the child’s fingernails were collected by the parents at the age of three. From five to six years of age, baby teeth were also collected once they fell out. Teeth and nails were used to assess chemical pollutants.

Biothèque

The biobank includes approximately 80,000 samples. Most samples are stored at -80°C at the Biological Ressources Center of the Grenoble Alpes University Hospital

Health factors

To learn more about the SEPAGES protocol:
Please download the scientific article on the study protocol: S.Lyon-Caen et al. «Deciphering the Impact of Early-Life Exposures to Highly Variable Environmental Factors on Foetal and Child Health: Design of SEPAGES Couple-Child Cohort». Int J Environ Res Public Health, 2019 October.
Download the article