Contribution of in utero drug exposure when interpreting hair results in young children

Hair toxicological analysis of infants and their mothers: a 5-year retrospective study focusing on cocaine

Prenatal and infant exposure to drugs of abuse is an emerging social and public health problem affecting children health and which may relate to child abuse and neglect. Exposure to drugs of abuse may occur through different routes, including intrauterine, breastfeeding, accidental intake, passive inhalation, and intentional administration. Currently, cases of suspected exposure can be investigated by hair toxicological analysis, the interpretation of which is, however, often difficult, leading to consequent difficulties in the management of such cases. In order to provide a contribution in terms of interpretation of the analytical results, this study aimed to search for the possible existence of elements, from a toxicological point of view, indicative towards the route of exposure. A retrospective study was performed on cases of suspected exposure to drugs of abuse in children aged 0-1 year, evaluated at a University Hospital between 2018 and 2022. Data of children hair toxicological analysis were analyzed and then compared with those of their mothers, when available; 41.6% children tested positive for cocaine. The study found a significant correlation between cocaine and benzoylecgonine concentrations, and a benzoylecgonine/cocaine ratio that tends to decrease as the age of children increases. From the comparison with mothers, a child/mother cocaine concentration ratio lower than 1 was found in all cases of hair sampled within the first week of life, and a ratio greater than or equal to 1 in all cases in which the sampling was performed later. These results, if confirmed in a larger cohort, could represent a contribution in the interpretation of cases of infant exposure to drugs of abuse and be integrated in the context of their multidisciplinary evaluation.

Hair testing applied to the assessment of in utero exposure to drugs: Critical analysis of 51 cases of the University Hospital of Verona

The work discusses the results of hair and urine testing performed in 51 cases of suspected in utero drug exposure handled at the University Hospital of Verona from 2016 to 2022. On the day of birth or the day after birth, urine from mother and newborn (UM and UN) and hair from mother (HM), newborn (HN) and father (HF), if possible, were collected. Urine underwent immunoassay and GC-MS analysis, whereas hair underwent LC-MS/MS and GC-MS/MS analysis. In 50 out of 51 cases, HM and/or HN were available. In 92% of them, hair testing resulted in a positive, often (>50% cases) for more than one class of substance. The most detected substances were cocaine, opiates, methadone and cannabinoids. Maternal segmental analysis showed a prevalent decreasing concentration trend during pregnancy in case of positivity for one class of substances, whereas, as expected, a neatly prevalent increasing trend in the case of positivity for more than one class of substances. In nine cases, HF was also available, resulting in all being positive, usually for the same classes of substances identified in HM, thus questioning parental responsibility. In 33 cases, urine samples from the mother or newborn were also collected. Of them, 27 cases (82%) tested positive, showing peri-partum drug consumption and then confirming the severity of the addiction. Hair testing showed to be a reliable diagnostic tool to investigate in utero drug exposure because of the possibility of obtaining a complete picture of maternal addictive behaviour and family background, thanks to segmental maternal hair analysis and father hair testing.

Interpretation of hair and nails findings in an infant death case related to maternal addiction to tramadol

An 11-month-old boy was found dead. Autopsy findings (cyanosis and polyvisceral congestion) and blood tramadol (TR) concentration of 6240 μg/L were consistent with an acute TR intoxication. In this poisoning situation, owing to the mother's statements (TR addiction leading to daily TR-orange juice mixture preparation accidentally used for the baby bottle preparation by the mother's partner), and the question of possible previous TR administrations to the infant, hair and/or nails (infant, mother, partner, 6-year-old sister) analysis was performed. Hair (2-cm-long hair segments from proximal [S1] to distal [S3]) and nails concentrations (pg/mg; nd: not detected) were as follows: Infant (hair: TR 1420 [S1], 1622 [S2], 2736 [S3]; O-DMT 16-38; N-DMT 34-100 [TR in significant quantities in the hair decontamination bath]-toenails: TR 584; O-DMT 8; N-DMT 15), mother (hair: TR 2340 [S1], 2150 [S2], 2500 [S3]; O-DMT 704-1170; N-DMT 827-1360), mother's partner (fingernails: TR 72; O-DMT nd; N-DMT nd) and sister (hair: TR 261 [S1], 524 [S2]; O-DMT 15 [S1], 16 [S2]; N-DMT 20 [S1], 38 [S2]). Metabolite ratio (infant and sister hair) was comparable to those observed in hair of pharmaceutical industry employees manufacturing tramadol. TR in washing baths, low observed nail concentrations (infant and partner) confirm (i) TR-related mother's addiction and (ii) external contamination issues (TR in sweat of the child at the time of death and in living environment) to explain the infant's keratinized samples results. This case report illustrates the interest of analyzing keratinized matrices of the whole family in such a situation.

Pharmacokinetics of Cannabis and Its Derivatives in Animals and Humans During Pregnancy and Breastfeeding

Cannabis is one of the most widely used illicit drugs during pregnancy and lactation. With the recent legalization of cannabis in many countries, health professionals are increasingly exposed to pregnant and breastfeeding women who are consuming cannabis on a regular basis as a solution for depression, anxiety, nausea, and pain. Cannabis consumption during pregnancy can induce negative birth outcomes such as reduced birth weight and increased risk of prematurity and admission to the neonatal intensive care unit. Yet, limited information is available regarding the pharmacokinetics of cannabis in the fetus and newborn exposed during pregnancy and lactation. Indeed, the official recommendations regarding the use of cannabis during these two critical development periods lack robust pharmacokinetics data and make it difficult for health professionals to guide their patients. Many clinical studies are currently evaluating the effects of cannabis on the brain development and base their groups mostly on questionnaires. These studies should be associated with pharmacokinetics studies to assess correlations between the infant brain development and the exposure to cannabis during pregnancy and breastfeeding. Our project aims to review the available data on the pharmacokinetics of cannabinoids in adults, neonates, and animals. If the available literature is abundant in adult humans and animals, there is still a lack of published data on the exposure of pregnant and lactating women and neonates. However, some of the published information causes concerns on the exposure and the potential effects of cannabis on fetuses and neonates. The safety of cannabis use for non-medical purpose during pregnancy and breastfeeding needs to be further characterized with proper pharmacokinetic studies in humans feasible in regions where cannabis has been legalized. Given the available data, significant transfer occurs to the fetus and the breastfed newborn with a theoretical risk of accumulation of products known to be biologically active.

High risk of misinterpreting hair analysis results for children tested for methadone

The major problem after testing the hair of a child for drugs is the interpretation of the findings. In 2016, the laboratory received several hair specimens with the request to verify if there was any evidence of previous methadone exposure by the donor of the sample. Case 1 was a child admitted to the Emergency Unit for intense sedation and breathing difficulties. Cases 2-4 involved children found dead at home. In all cases, methadone and EDDP, its metabolite, were found in blood. After decontamination, the hair was analysed with LC-MS/MS for methadone and EDDP. The LOQ for both drugs was 10pg/mg. Concentrations were in the range 60-1590 and <10-220pg/mg for methadone and EDDP, respectively. In all of the cases, segmental analysis revealed approximately the same amount of drug along the hair lock. As a consequence, contamination was considered as an issue and interpretation of the results was a challenge that deserves particular attention. It must be considered that the amount of hair from children, available for analysis, can be low, particularly when several drugs have to be tested. This has consequences on the limit of quantitation and the identification of the metabolite(s). It must be also noted that hair from children is finer and more porous in comparison with adult (risk of higher contamination by sweat versus adults). It is very difficult to put any window of detection when testing for drugs in young children as hair growing is asynchronous. It is even more complicated as it has been demonstrated that drugs can be incorporated during pregnancy in the hair of the foetus, which will contribute to the positive findings after delivery. Several weeks or months after delivery, identification of a drug in hair can indicate: 1, in-utero exposure, or 2, exposure after delivery, or 3, a mix of both situations. Whereas the detection of drugs in a child's hair unambiguously shows drug handling in the environment of the child, it is difficult to distinguish between systemic incorporation into hair after ingestion or inhalation and external deposition into hair from smoke, dust, or contaminated surfaces. However, the interpretation of hair results with respect to systemic or only external exposure is particularly important in case of children for a realistic assessment of the toxic health risk. Practising scientists have the responsibility to inform the child protection authorities, courts, etc about these limitations.