Infant exposure to drugs of abuse investigated by hair analysis.

Infant exposure to drugs of abuse represents a worldwide problem whose extent is difficult to estimate. Despite the potentially serious health consequences, few data concerning exposure in children under 1 year of age are available. Since in clinical and forensic settings, neonatal and infant hair testing represents a useful method for investigating suspected drug exposures, an observational retrospective study was performed on hair analysis of children under 1 year of age evaluated at the University Hospital of Padova between 2018 and 2022 with the aim of estimate the extent and define the characteristics of this phenomenon in the reference setting. The sample included 102 infants. Chemical-toxicological analyses were requested in 38 cases (37.3%) because of clinically suspicious symptoms of the child (e.g., neuropsychiatric symptoms and suspected neonatal abstinence syndrome) and in 64 cases (62.7%) because of other reasons (e.g., maternal drug history, at-risk environment, and suspected maltreatment). Based on the presence or absence of symptoms in the request, the sample was subdivided into two groups. Hair analysis in these two showed the presence of drug of abuse, respectively, in 44.7% and 67.2% of the cases (p = 0.026). Cocaine was the most frequently detected substance, followed by opiates, and it was detected less frequently in cases investigated for suspicious clinical symptoms (p < 0.05). The results confirm the difficulties in interpreting the clinical picture and in defining the extent of exposure to drugs of abuse. An integrated assessment is fundamental to interpret the case and achieve adequate care of the child.