During their first year of life, children spend more than half their time sleeping, a function essential to their neurodevelopment. This period of maturation and development of the future adult is considered extremely vulnerable to environmental exposure. During this period, the child's diet is mainly provided by breastfeeding, where persistent chemical substances have been found. A cocktail of 19 mostly persistent substances (POPs) present in breast milk has recently been identified as the main contributor to neurodevelopmental risk. However, the reality of their impact on neurophysiological development, in particular on infant sleep, has yet to be assessed.

In this project, the sleep of children under 6 months of age will be studied using an actimetry watch worn for 7 days by the child, accompanied by a sleep diary. Exposure to environmental pollutants will be assessed by measuring their presence in the infant's milk (breastfeeding) and wearing a silicone bracelet to collect air pollutants. A questionnaire on exposure will complement this evaluation.

Inclusion Criteria:

• Infant less than 6 months of age still on milk diet (total)

Exclusion Criteria:

• Infants with neurological or neurobehavioral disorders
• Families who wish to relocate within 7 days of inclusion
• Minor parents deprived of their parental rights, not understanding French, in a state of stress, overwhelmed or vulnerable.
• Non-affiliation to a social security system