Fatty Acid Ethyl Esters In Meconium Research Articles

Fatty acid ethyl esters in meconium and substance use in adolescence

Prenatal alcohol exposure (PAE) continues to be a serious public health problem, yet no reliable clinical tools are available for assessing levels of drinking during pregnancy. Fatty acid ethyl esters (FAEEs), the nonoxidative metabolites of ethanol measured in meconium, are potential biomarkers to quantify the level of PAE. The association between the concentrations of FAEEs from meconium and adolescent substance use and related problems was examined in a prospective birth-cohort of adolescents exposed to alcohol and drugs in utero. FAEEs were quantified with gas chromatography via a flame ionization detector. Meconium was analyzed for FAEEs in 216 newborns; 183 of them (81 boys, 102 girls) were assessed at age 15 for alcohol, tobacco, and marijuana use using biologic assays and self-report. Substance use problems were assessed using the Problem Oriented Screening Instrument for Teenagers. Findings from multivariable logistic regression analyses indicated that, after controlling for other prenatal drug exposure and covariates, higher concentrations of FAEEs (ethyl myristate, ethyl palmitate, ethyl oleate, ethyl linoleate, ethyl linolenate, and ethyl arachidonate) were related to a greater likelihood of marijuana use and experiencing substance use problems, but not tobacco or alcohol use, at age 15. Elevated levels of FAEEs in meconium may be promising markers for PAE, identifying newborns at risk for early substance use and developing substance use problems.

Association of fatty acid ethyl esters in meconium with behavior during childhood

ObjectiveTo examine associations between amounts of fatty acid ethyl esters (FAEEs) in meconium and behavior in school aged children exposed to alcohol and drugs in utero. MethodsA secondary analysis of a prospective cohort of cocaine, polydrug exposed children, primarily African-American, low socioeconomic status, recruited at birth into a longitudinal study. FAEEs were quantified with gas chromatography via a flame ionization detector. Meconium was analyzed for FAEEs for 216 newborns of whom 194 were assessed with the Child Behavior Checklist (CBCL) at ages 4, 6, 9, 10, 11, and 12. Generalized estimating equation analyses were used to assess the relationship of quantity of FAEEs to outcomes, controlling for maternal psychological distress. ResultsHigher concentrations of FAEEs (ethyl myristate, ethyl palmitate, ethyl oleate, ethyl linoleate, and ethyl linolenate) were associated with caregiver reported aggressive and/or delinquent behavior at ages 10 and 12. After control for caregiver psychological distress, and age, significant (p < 0.05) FAEE by age interactions were found for ethyl myristate for aggression and for ethyl oleate, ethyl linoleate and ethyl linolenate for delinquency. Thus, higher concentrations of FAEE were related to more caregiver reported aggressive and delinquent behaviors of clinical significance at ages 10 and 12. ConclusionHigher concentrations of FAEEs in meconium are potential markers for children at risk for aggressive and delinquent behaviors related to the effects of prenatal alcohol exposure.

Fatty acid ethyl esters in meconium: A biomarker of fetal alcohol exposure and effect.

To determine if meconium fatty acid ethyl esters (FAEE) in rat pups is a good biomarker of prenatal exposure and effect to alcohol, three groups of pregnant rats were studied: one control (pair fed) and two treatment groups given 25% alcohol at 2.2 or 5.5 g-1 kg-1 d-1. The pups were delivered on day 20 and, for each dam, were separated into a male and female group. The body, brain, intestines, and placenta of the pups were obtained, weighed, and stored at -20°C. The pups' intestines (as surrogate of meconium) from each group were pooled, and meconium was analyzed by gas chromatography/mass spectroscopy for FAEE. The meconium showed the following FAEE: ethyl palmitate, ethyl stearate, and ethyl linolenate and were only found in the alcohol-treated group and with high specificity but low sensitivity. Mean body weight of the pups was lower in the treatment groups compared to the control groups. Ethyl palmitate concentration correlated negatively to the pups' mean body and brain weights. Therefore, ethyl palmitate, stearate, and linolenate, in meconium of rat pups prenatally exposed to alcohol, are useful biomarkers of prenatal alcohol exposure, with ethyl palmitate a good biomarker of adverse effect on the pups' body and brain weight.

Prevalence of heavy fetal alcohol exposure by analysis of meconium fatty acid ethyl esters; A nat ionwide canadian study

Prevalence of heavy fetal alcohol exposure by analysis of meconium fatty acid ethyl esters; A nat ionwide canadian study

Association of Fatty Acid Ethyl Esters in Meconium of Neonates with Growth Deficits at Birth: a Prospective, Single-Centre Cohort Study.

BackgroundIn this prospective cohort study, we investigated the association between fatty acid ethyl esters (FAEEs) in meconium as biomarkers of prenatal ethanol exposure and growth deficits, as birth outcomes, that constitute several of the key cardinal features of fetal alcohol syndrome.MethodsA total of 157 meconium samples were collected from enrolled infants within 24 hours of birth, and nine FAEEs were quantified using liquid chromatography/tandem mass spectrometry. The relationships between cumulative concentrations of nine species of FAEEs in meconium and birth parameters of growth (age-sex-specific centiles of head circumference [HC], weight, and length) and respective and combined birth outcomes of growth deficits (HC ≤ 10th centile, weight ≤ 10th centile, and length ≤ 10th centile) were determined.ResultsMultivariate logistic regression analysis demonstrated that higher cumulative concentrations of meconium FAEEs correlated with elevated risks for HC and length, both, 10th percentile or less (adjusted odds ratio [aOR], 2.94; 95% confidence interval [CI], 1.12–7.74; P = 0.029) and HC and weight and length, all of them, 10th percentile or less (aOR, 3.27; 95% CI, 1.12–9.59; P = 0.031).ConclusionThe elevated cumulative FAEEs in meconium were associated with combined growth deficits at birth, specifically HC and length, both, 10th percentile or less, which might be correlated with detrimental alcohol effects on fetal brain and bone development, suggesting a plausible alcohol-specific pattern of intrauterine growth restriction.

Ethyl linolenate is elevated in meconium of very-low-birth-weight neonates exposed to alcohol in utero

Background:The health implications of in utero alcohol exposure have been difficult to study in very-low-birth-weight newborns (VLBW) because of an inability to identify maternal alcohol exposure. Fatty acid ethyl esters (FAEEs) are elevated in meconium of alcohol-exposed term newborns. We hypothesized that meconium FAEEs would be similarly elevated in alcohol-exposed VLBW premature newborns.Methods:In a retrospective cohort study of 64 VLBW neonates, newborns were classified into Non-Exposed, Any Exposure, or Weekly Exposure groups based on an in-depth structured maternal interview. Meconium FAEE concentrations were quantified via gas chromatography mass spectrometry.Results:Alcohol exposure during Trimester 1 (Any Exposure) occurred in ~30% of the pregnancies, while 11% of the subjects reported drinking ≥ 1 drink/week (Weekly Exposure). Meconium ethyl linolenate was higher in Any Exposure (P = 0.01) and Weekly Exposure groups (P = 0.005) compared to the Non-Exposed VLBW group. There was a significant positive correlation between Trimester 1 drinking amounts and the concentration of meconium ethyl linolenate (P = 0.005). Adjusted receiver operating characteristic (ROC) curves evaluating ethyl linolenate to identify alcohol-exposed VLBW newborns generated areas under the curve of 88% with sensitivities of 86–89% and specificities of 83–88%.Conclusion:Despite prematurity, meconium FAEEs hold promise to identify the alcohol-exposed VLBW newborn.

Association of Fatty Acid Ethyl Esters in Meconium and Cognitive Development during Childhood and Adolescence

To examine associations between amounts of fatty acid ethyl esters (FAEEs) in meconium and cognitive development in school-aged children exposed to alcohol and drugs in utero. A secondary analysis of a prospective cohort of children, primarily African American and of low socioeconomic status, that was recruited at birth. FAEEs were quantified with gas chromatography via a flame ionization detector. Meconium was analyzed for FAEEs in 216 newborns; 191 of these infants were assessed for IQ at ages 9, 11, and 15 years with the Wechsler Intelligence Scales for Children-Fourth Edition. Longitudinal mixed model analyses indicated that, after we controlled for maternal and child covariates, greater concentrations of FAEEs (ethyl myristate, ethyl oleate, ethyl linoleate, and ethyl linolenate) were associated with lower Wechsler Intelligence Scales for Children-Fourth Edition Verbal Comprehension Index, Working Memory Index, and Full-Scale IQ scores. Associations of FAEEs with Verbal Comprehension Index, Working Memory Index, and Full-Scale IQ did not vary over time. No associations of FAEEs with Perceptual Reasoning and Processing Speed Indices were found. Elevated levels of FAEEs in meconium are potential markers for identifying newborns at risk for poor cognitive development related to prenatal alcohol exposure.

Quantification of fatty acid ethyl esters (FAEE) and ethyl glucuronide (EtG) in meconium for detection of alcohol abuse during pregnancy: Correlation study between both biomarkers

This article presents results from 47 meconium samples, which were analyzed for fatty acid ethyl esters (FAEE) and ethyl glucuronide (EtG) for detection of gestational alcohol consumption. A validated microwave assisted extraction (MAE) method in combination with GC–MS developed in the Institute of Forensic Science (Santiago de Compostela) was used for FAEE and the cumulative concentration of ethyl myristate, ethyl palmitate and ethyl stearate with a cut-off of 600ng/g was applied for interpretation. A simple method for identification and quantification of EtG has been evaluated by ultrasonication followed solid phase extraction (SPE). Successful validation parameters were obtained for both biochemical markers of alcohol intake. FAEE and EtG concentrations in meconium ranged between values lower than LOD and 32,892ng/g or 218ng/g respectively. We have analyzed FAEE and EtG in the same meconium aliquot, enabling comparison of the efficiency of gestational ethanol exposure detection. Certain agreement between the two biomarkers was found as they are both a very specific alcohol markers, making it a useful analysis for confirmation.

Incidence of prenatal alcohol exposure in Prince Edward Island: a population-based descriptive study.

Fetal alcohol spectrum disorder (FASD) is a leading preventable cause of neurodevelopmental disability in North America. The stigma associated with alcohol use and abuse during pregnancy makes it difficult to obtain information on prenatal alcohol use through self-reporting. We assessed the incidence of prenatal alcohol exposure in Prince Edward Island to facilitate future public health initiatives addressing FASD. Prenatal alcohol exposure was examined via population-based collection of meconium and analysis of fatty acid ethyl esters (FAEEs). Fatty acid ethyl esters are nonoxidative metabolites of ethanol that are produced in the fetus. Meconium FAEE concentrations of 2.0 nmol/g or greater are indicative of frequent prenatal alcohol exposure during the last 2 trimesters of pregnancy. Samples were collected from 1307 neonates between Nov. 8, 2010, and Nov. 8, 2011, in hospitals in PEI, or from those born to mothers who resided in PEI but gave birth in Halifax, Nova Scotia. Samples were frozen and shipped for analysis. Fatty acid ethyl esters were analyzed by gas chromatography-mass spectrometry and quantified by means of deuterated internal standards. Of the 1307 samples collected, 1271 samples were successfully analyzed. Positive results for FAEEs were obtained in 3.1% (n = 39) of samples collected within the first 24 hours after birth. Not all neonates exposed to heavy prenatal alcohol in utero will exhibit FASD; based on current estimates of predictive value for disease by exposure, our findings suggest that 1.3% of neonates born in PEI during this 1-year period will have FASD. In its application to an entire provincial birth cohort, this study successfully implemented a public health-centred approach for evaluating population-based risk of FASD, with implications for practice across Canada.

Dose-response and time-response analysis of total fatty acid ethyl esters in meconium as a biomarker of prenatal alcohol exposure

Little is known on how the dose and timing of exposure co-influence the cumulative concentration of fatty acid ethyl esters (FAEEs) in meconium. The objective of the study was to assess the cumulative concentration of FAEEs in meconium as a biomarker of light, moderate, or heavy prenatal alcohol exposure occurring at either first, second, or third trimesters of pregnancy. History of prenatal alcohol exposure was obtained in the 34th week of gestation from 294 pregnant women. Meconium was collected from their babies within the first 6 to 12 h after birth and examined for the presence of nine FAEEs. No significant differences were identified between the cumulative levels of FAEEs in the meconium from the babies born to abstainers and those born to mothers with history of light-to-moderate prenatal alcohol exposure during their pregnancy. Light-to-moderate prenatal alcohol exposure cannot be reliably predicted by the cumulative FAEE concentrations in meconium of exposed babies. A cumulative FAEE level of >10 nmol/g would be required to consider that prenatal alcohol exposure during the second to third trimesters occurred at risky levels in the absence of reliable maternal history of ethanol exposure.

Meconium Fatty Acid Ethyl Esters as Biomarkers of Late Gestational Ethanol Exposure and Indicator of Ethanol-Induced Multi-Organ Injury in Fetal Sheep

BackgroundMeconium fatty acid ethyl esters (FAEE) constitute a biomarker of heavy fetal ethanol exposure. Our objective was to measure meconium FAEE in fetal sheep following daily, relatively moderate-dose ethanol exposure in late gestation, and to evaluate their utility in identifying fetal organ-system injury.MethodsPregnant ewes received ethanol (0.75 g/kg; n = 14) or saline (n = 8) via 1-h IV infusion daily during the third trimester equivalent, while additional pregnant sheep served as untreated controls (n = 6). The daily ethanol regimen produced similar maximal maternal and fetal plasma ethanol concentrations of 0.11–0.12 g/dL. Ewes and fetuses were euthanized shortly before term, and meconium was collected and analyzed for FAEE (ethyl palmitate, stearate, linoleate, and oleate).ResultsMeconium total FAEE concentration was significantly higher in ethanol-exposed fetuses compared with controls, and a positive cut-off of 0.0285 nmol total FAEE/g meconium had 93.3% sensitivity and specificity for detecting fetal ethanol exposure. When the studied animals (ethanol-exposed and controls) were classified according to meconium FAEE concentration, FAEE-positive and FAEE-negative groups frequently differed with respect to previously examined pathological endpoints, including nephron endowment, lung collagen deposition, cardiomyocyte maturation, and tropoelastin gene expression in cerebral vessels. Furthermore, in all studied animals as a group (ethanol-exposed and controls combined), meconium FAEE concentration was correlated with many of these pathological endpoints in fetal organs.ConclusionsWe conclude that, in fetal sheep, meconium FAEE could serve as a biomarker of daily ethanol exposure in late gestation and could identify fetuses with subtle ethanol-induced toxic effects in various organs. This study illustrates the potential for using meconium FAEE to identify neonates at risk for dysfunction of major organs following in-utero ethanol exposure that does not result in overt physical signs of ethanol teratogenicity.

The feasibility and cost of neonatal screening for prenatal alcohol exposure by measuring phosphatidylethanol in dried blood spots.

Accurate confirmation of prenatal alcohol exposure (PAE) is required as a diagnostic criterion for the majority of children adversely affected by PAE who do not manifest the physical features associated with fetal alcohol syndrome. A number of ethanol biomarkers have been used to assess PAE, often with suboptimal results. The purpose of this study was to evaluate the feasibility and cost of PAE screening in newborns by measuring phosphatidylethanol (PEth) in dried blood spot (DBS) cards. The feasibility of collecting an additional DBS card during routine newborn screening and the background prevalence of PAE were evaluated in a de-identified sample of newborn children delivered at the University of New Mexico Hospital. Electronic orders to collect DBS cards from newborns who continue to bleed after the routine newborn screen, glucose, or hematocrit testing were initiated for all infants delivered during a 4-week time frame. Specimens were sent to a contract laboratory for PEth analysis by liquid chromatography-tandem mass spectrometry. A cost analysis was conducted to compare the cost of PAE screening by PEth in DBS versus PEth in conventional blood specimens and by meconium fatty acid ethyl esters. From 230 collected cards, 201 (87.4%) had at least 1 full blood spot (amount sufficient for PEth analysis), and 6.5% had PEth >20ng/ml indicative of potential PAE in late pregnancy. PAE screening by PEth in DBS is logistically simpler and less expensive compared with 2 other screening approaches. These results indicate that screening for PAE in DBS cards is a feasible procedure and that a majority of infants have enough blood after the routine heel prick to fill an additional card. Moreover, screening by PEth analysis from DBS cards is cost-efficient. The acceptability of such screening by parents and corresponding ethical issues remain to be investigated.

Neonatal screening for prenatal alcohol exposure: Assessment of voluntary maternal participation in an open meconium screening program

Meconium fatty acid ethyl esters (FAEEs) are validated biomarkers of fetal alcohol exposure. Meconium FAEE testing can potentially be used as a screen by health-care professionals to identify neonates at-risk for Fetal Alcohol Spectrum Disorder, thereby permitting diagnostic follow-up of these children and early intervention in those who develop disabilities. The purpose of this study was to assess whether women would willingly partake in a screening program of this nature. This was determined by launching a pilot screening program for prenatal alcohol exposure in a high-risk obstetric unit previously shown to have a high prevalence of FAEE-positive meconium via anonymous meconium testing. The program involved voluntary testing of meconium for FAEEs and long-term developmental follow-up of positive cases through an existing public health program. The participation rate in the screening program was significantly lower than when testing was conducted anonymously (78% vs. 95%, respectively; p < 0.05), and the positivity rate was 3% in contrast to 30% observed under anonymous conditions (p < 0.001). These low rates suggest that the majority of mothers who consumed alcohol in pregnancy refused to participate. We conclude that despite the potential benefits of such screening programs, maternal unwillingness to consent, likely due to fear, embarrassment, and guilt, may limit the effectiveness of meconium testing for population-based open screening, highlighting the need for public education and social marketing efforts for such programs to be of benefit.

An improved method for rapidly quantifying fatty acid ethyl esters in meconium suitable for prenatal alcohol screening

Fatty acid ethyl esters (FAEEs) are nonoxidative metabolites of ethanol, and elevated levels of FAEE in meconium are a useful biomarker for heavy prenatal alcohol exposure. FAEE in meconium has been recommended as useful and cost-effective for universal screening for prenatal alcohol exposure. To support an efficient universal screening program, an analytical method to detect and quantify FAEE in meconium needs to be accurate, inexpensive, and rapid. The purpose of this study was to develop an analytical method that would satisfy these criteria and to validate this method using established laboratory guidelines. A method was developed and validated to detect and quantify four FAEEs (ethyl palmitate, ethyl linoleate, ethyl oleate, and ethyl stearate) from 0.5 g of meconium using d 5 -ethyl esters as internal standards. The sample undergoes liquid–liquid extraction with heptane:acetone, the heptane layer is isolated and evaporated, and then, the resulting residue undergoes headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry. The detection limits of the four FAEEs ranged from 0.020 to 0.042 nmol/g and are 6- to 25-fold lower than the individual FAEE threshold concentrations (0.5 nmol/g). This method also has good precision with the coefficient of variation ranging from 2.6 to 19.4% for concentrations of individual FAEE between 0.5 and 2.62 nmol/g meconium ( n = 4). Calculated concentrations of FAEE that underwent extraction from meconium were 100–101% of the expected concentration, demonstrating the accuracy of the method. The peak shape and retention time of each FAEE were unaffected by the presence of the matrix, and there is no carryover at clinically relevant concentrations. This method was also able to produce clean chromatograms from meconium samples that could not be quantified using a previous method because of high chromatographic background. This method provides an optimal approach to detecting and quantifying FAEE in meconium that could be used in a universal screening program for prenatal alcohol exposure.

Rates of fetal alcohol exposure among newborns in a high-risk obstetric unit

Meconium fatty acid ethyl esters (FAEEs) are sensitive and specific biomarkers for prenatal alcohol exposure (PAE) in pregnancy. We recently reported a 2.5% rate of FAEE positive meconium in a general population sample of infants born in the region of Grey-Bruce, Ontario. Women in this region with high-risk pregnancies are transferred to a tertiary care facility in London, Ontario. The objective of this study was to determine, in a population-based sample, whether high-risk pregnancies are associated with an increased risk of in utero alcohol exposure. Grey-Bruce residents transferred to the high-risk obstetric unit of St. Joseph's Health Care in London, Ontario were identified and consented to this anonymous prevalence study. Meconium was collected and analyzed for FAEE using gas chromatography with mass spectrometry. The prevalence of FAEE positive meconium was compared with the population-based prevalence in the Grey-Bruce. Fifty meconium specimens were collected from August 1, 2006 to July 31, 2007. Fifteen (30%) specimens tested positive for FAEE. The results indicate that infants born in the high-risk obstetric unit had a 12-fold higher risk of screening positive for second and third trimester alcohol exposure compared with infants born in the general population of Grey-Bruce (relative risk = 12.04, 95% confidence interval = 6.40–22.65, P < .0001). These results suggest that the high-risk pregnancies should be screened for PAE and followed-up for potential diagnosis of fetal alcohol spectrum disorder.

Population Baseline of Meconium Ethyl Glucuronide and Ethyl Sulfate Concentrations in Newborns of Nondrinking Women in 2 Mediterranean Cohorts

The detection of ethyl glucuronide (EtG) and ethyl sulfate (EtS) in meconium has been investigated recently as an alternative to meconium fatty acid ethyl esters (FAEEs) measurement as an objective estimate of prenatal alcohol exposure, independent of maternal self-reporting. We report the results of the first study conducted to investigate the concentrations of EtG and EtS in meconium from newborns with and without intrauterine exposure to ethanol, defined by questionnaire and meconium FAEEs concentration. FAEEs, EtG, and EtS were quantified by liquid chromatography tandem mass spectrometry in meconium samples obtained from the Arcispedale Santa Maria Nuova, Reggio Emilia, Italy (n = 80) and from the Hospital del Mar in Barcelona, Spain (n = 105). Median EtG and EtS values in meconium from newborns without intrauterine exposure to ethanol varied between 0.100 and 0.140 nmol/g and 0.010 and 0.020 nmol/g in Reggio Emilia and Barcelona samples, respectively. In meconium from newborns with uncertain prenatal ethanol exposure, the EtG median value was 0.160 nmol/g in the Italian cohort and 0.250 nmol/g in the Spanish one. The median EtS concentration was 0.020 in both cohorts. EtG and EtS median values in 5 meconium samples from newborns of heavily drinking mothers were 7.240 nmol/g and 0.033 nmol/g, respectively. A positive cutoff of 2.0 nmol/g for EtG yielded the best sensitivity and specificity (100%) to discriminate for true prenatal exposure to ethanol. It was not possible to establish a proper cutoff for EtS because of the low number of positive samples. Based on our results, meconium EtG can be proposed as an alternate biomarker for intrauterine alcohol exposure. In contrast to the 7 FAEEs, EtG is just one molecule that could be screened in meconium samples from all newborns by a simple, low-cost, easy-to-perform immunoassay, which can be routinely applied in neonatology wards for the early diagnosis of prenatal exposure to ethanol.

Quantification of fatty acid ethyl esters (FAEE) and ethyl glucuronide (EtG) in meconium from newborns for detection of alcohol abuse in a maternal health evaluation study

Fatty acid ethyl esters (FAEE) and ethyl glucuronide (EtG) were determined in 602 meconium samples in a maternal health evaluation study for detection of gestational alcohol consumption. A validated headspace solid phase microextraction method in combination with GC-MS was used for FAEE and the cumulative concentration of ethyl palmitate, ethyl linoleate, ethyl oleate, and ethyl stearate with a cut-off of 500 ng/g was applied for interpretation. A new and simple method was developed and validated for quantification of EtG from 10-20 mg meconium with D(5)-EtG as internal standard consisting of 30 min. extraction with methanol/water (1:1, v/v), evaporation of methanol, filtration of the aqueous solution through a cellulose filter and injection into LC-MS-MS. The limits of detection and quantification for EtG were 10 and 30 ng/g, the recovery 86.6 to 106.4% and the standard deviation of the concentrations ranged from 13% at 37 ng/g to 5% at 46,700 ng/g (N = 6). FAEE above the cut-off were found in 43 cases (7.1%) with cumulative concentrations between 507 and 22,580 ng/g and with one outlier of about 150,000 ng/g (EtG not detected). EtG was detected in 97 cases (16.3%) and concentrations between LOD and 10,200 ng/g with another outlier of 82,000 ng/g (FAEE 10,500 ng/g). Optimal agreement between the two markers was obtained with a cut-off for EtG of 274 ng/g and 547 cases with both FAEE- and EtG-negative, 33 cases with both FAEE- and EtG-positive, nine cases with FAEE-positive and EtG-negative, and seven cases with FAEE-negative and EtG-positive. Differences in physical, chemical, and biochemical properties and in the pharmacokinetic behavior are discussed as reasons for the deviating cases. In none of the 602 cases, serious alcohol consumption was reported by the mothers and no evidence for gestational ethanol exposure was observed in the medical investigation of the newborns. It is concluded that the combined use of FAEE and EtG in meconium as markers for fetal alcohol exposure essentially increases the accuracy of the interpretation and helps to avoid false positive and false-negative results.

Ethyl glucuronide and ethyl sulfate in meconium and hair-potential biomarkers of intrauterine exposure to ethanol

This study investigated ethyl glucuronide (EtG) and ethyl sulfate (EtS) concentration in meconium and in maternal and neonatal hair (HEtG and HFAEEs, respectively) as potential markers of intrauterine exposure to ethanol together with meconium fatty acid ethyl esters (FAEEs) in a cohort of 99 mother–infant dyads, 49 coming from the Arcispedale of Reggio Emilia (Italy) and 50 from the Hospital del Mar of Barcelona (Spain). FAEEs, EtG and EtS were measured in meconium samples using liquid chromatography–tandem mass spectrometry. A head space-solid phase microextraction-gas chromatography–mass spectrometry was used to test HEtG and HFAEEs in hair samples from mothers and their newborns. Eighty-two meconium samples (82.8%) tested positive for EtG, 19 (19.2%) for EtS while 22 (22.2%) showed FAEEs levels higher than 2 nmol/g, the cut-off used to differentiate daily maternal ethanol consumption during pregnancy from occasional or no use. Although EtG and EtS in meconium did not correlate with total FAEEs concentration, a good correlation between EtG, EtS and ethyl stearate was observed. Moreover, EtG correlated well with ethyl palmitoleate, while EtS with ethyl laurate, myristate and linolenate. Neither maternal nor neonatal hair appears as good predictors of gestational ethanol consumption and subsequent fetal exposure in these mother–infant dyads. In conclusion, these data show that meconium is so far the best matrix in evaluating intrauterine exposure to ethanol, with EtG and EtS being potentially good alternative biomarkers to FAEEs.

Potential Role of the Placenta in Fetal Alcohol Spectrum Disorder

Mediators of susceptibility to alcohol-related toxicity in the prenatal environment are relatively unknown. The placenta has been proposed as a potential source of variability in the fetal environment, primarily through its significant metabolic capabilities. Meconium is a toxicological matrix unique to the developing fetus that offers an opportunity to quantify fetal exposure to alcohol through the analysis of fatty acid ethyl esters (FAEE) [nonoxidative ethanol metabolites]. To explore the role of the placenta as a potential source of variability in mediating fetal alcohol exposure via meconium analysis of FAEE, by combining a clinical case report involving human dizygotic twins and a series of guinea pig littermates. Meconium was collected from a pair of dizygotic twins with clinical suspicion of prenatal alcohol exposure and analyzed for FAEE to confirm prenatal alcohol exposure. Meconium was also collected from a series of guinea pig pups prenatally exposed to alcohol at a daily dose of 4 g/kg/day administered to the pregnant dam. FAEE levels were analyzed by gas chromatography with flame ionization detection following liquid-liquid extraction from meconium. The dizygotic twin pair yielded positive meconium FAEE results (>2.00 nmoL/g) in the female twin (2.21 nmoL/g) and no detectable FAEE in the male twin. A total of 15 meconium samples were collected from 15 pups of five pregnant guinea pig litters. With the exception of one pair of littermates, meconium FAEE concentrations differed substantially within each litter (FAEE expressed in units of nmoL/g): litter 1 (0.996, 4.43, 1.36); litter 2 (5.17, 4.15, 0.00); litter 3 (5.16, 5.27); litter 4 (18.57, 8.26, 7.46); litter 5 (0.00, 4.32, 0.00, 1.27). Identical maternal ethanol exposure levels produced differing levels of fetal exposure in a dizygotic human twin pair and a series of guinea pig littermates as evidenced through FAEE meconium analysis. These data indicate that the placenta may have a previously unappreciated role in mediating ethanol-induced fetal injury.

Detection and quantification of fatty acid ethyl esters in meconium by headspace-solid-phase microextraction and gas chromatography–mass spectrometry

Meconium fatty acid ethyl esters (FAEEs) are currently used as biomarkers to detect heavy prenatal alcohol exposure. We introduce a novel technique to quantify FAEEs in meconium using headspace-solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS). This method improves on previous approaches by decreasing sample preparation time, eliminating the need for organic solvents, and reducing the required sample size. Using 50 mg of meconium, the detection limits of FAEEs ranged from 0.05 to 0.16 nmol/g and had good reproducibility making it ideal for routine analysis of clinical samples.