Maternal and foetal exposure to potentially toxic metals of modern weaponry and infant cognitive, sensorimotor, and socioemotional development: The role of breastfeeding

Toxic metals in new-generation weapons pose health risks to civilians, and pregnant women are especially vulnerable in wars. Studies have focused on single toxins, such as white phosphorus and depleted uranium, although civilians are exposed to multiple toxic metals. Research has mainly concentrated on toxic metals impacting new-born health but has neglected older infants’ development and salient dyadic factors. This study examines how maternal and new-born prenatal exposure to multiple carcinogen, neurotoxic, and teratogen metals during a war impacts infants’ sensorimotor, cognitive, and socioemotional development, and the role of breastfeeding in that association. The participants were 502 Palestinian mothers, pregnant during the 2014 War on Gaza, and their new-borns, recruited at childbirth (T1) and followed up at 6 months (T2; N = 392) and 18 months (T3; N = 358). At T1, maternal and new-born hair samples were tested for 18 toxic metals. At T2, mothers reported infants’ fine-gross-motor, language, and socioemotional skills, and at T3, psychologists tested their motor, cognitive-language, and socioemotional skills. Mothers reported breastfeeding practices at T2 and T3. Results showed that the timing of direct developmental impact of maternal and new-born loads of toxic metals differed, as mothers’ high loads of carcinogen metals was associated with infant developmental problems at 6 months, and new-borns’ high loads of carcinogen and teratogen metals predicted developmental problems at 18 months. Both maternal and new-born high toxic metal loads were associated with decreased breastfeeding intensity and duration. The impact of maternal, but not newborn's, exposure to toxic metals was mediated into infant development through decreased breastfeeding.