Brain Homogenate Stability for Stimulant Drugs.

Brain can a useful specimen for toxicology testing as it is a protected and isolated organ with lower metabolic activity than other tissues, but there is currently no published data supporting the stability of stimulant drugs in prepared brain homogenates. Brain homogenates were evaluated to determine the stability of the following stimulant drugs: amphetamine, benzoylecgonine, bupropion, cocaethylene, cocaine, ephedrine, methylenedioxyamphetamine, methylenedioxymethamphetamine, methamphetamine, and phentermine. Four different homogenates were prepared at a 1:4 dilution with deionized water and fortified at 500 ng/mL of: cocaine without sodium fluoride, cocaine with 1% sodium fluoride, stimulant drugs other than cocaine without sodium fluoride, and stimulant drugs other than cocaine with 1% sodium fluoride. The fortified homogenates were aliquoted into 13x100 mm screw cap tubes and stored at room temperature (~20 °C), refrigerated (2-8 °C), or frozen (< -5 °C) and analyzed in triplicate on Days 0, 1, 3, 7, 14, 30, 60, and 90. Analytes were considered stable as long as the difference in analyte/internal standard response ratio from Day 0 was less than 20% and the peaks met qualitative acceptance criteria. All analytes were stable for up to 90 days when stored frozen with or without sodium fluoride and had variable stability at all other evaluated conditions.

Assessment of urine drug screen utility at autopsy to predict laboratory postmortem blood toxicology.

When faced with increasing drug-related deaths and decline in practicing forensic pathologists, the need to quickly identify toxicology-related deaths is evident in order to appropriately triage cases and expedite turnaround times. Lateral flow immunoassays conducted pre-autopsy offer quick urine drug screen (UDS) results in minutes and are used to inform the need for autopsy. Over 1000 medicolegal cases were reviewed to compare UDS results to laboratory enzyme-linked immunosorbent assay (ELISA) blood results to evaluate how well autopsy UDS predicted laboratory findings. Mass spectral analysis was performed on ELISA-positive specimens and these data were used to investigate UDS false-negative (FN) results when possible. Five different UDS devices (STAT One Step Drug of Abuse dip card and cassette, Premiere Biotech multi-drug and fentanyl dip cards and ATTEST 6-acetylmorphine (6-AM) dip card) were tested encompassing 11 drug classes: 6-AM, amphetamine/methamphetamine, benzodiazepines, benzoylecgonine, fentanyl, methadone, opioids, phencyclidine, and delta-9-tetrahydrocannabinol. Sensitivity, specificity, efficiency, and positive and negative predictive values >80% indicated that UDS was useful for predicting cases involving benzoylecgonine, methadone, methamphetamine, and phencyclidine. UDS was unreliable in predicting amphetamine, benzodiazepines, fentanyl, and opiates-related cases due to a high percentage of FN (up to 11.2%, 8.0%, 12.4%, and 5.5%, respectively) when compared to ELISA blood results. For the later analytes, sensitivities were as low as 57.5%, 60.0%, 72.2%, and 66.7%, respectively. Overall results support that UDS cannot replace laboratory testing. Because UDS is subject to false-positive and FN results users must understand the limitations of using UDS for triage or decision-making purposes.

Examination of acetone findings in suspected drug-facilitated sexual assaults: A case series.

Acetone presence in human biological specimens can result from exogenous administration or endogenous production, resulting from diabetes, dietary composition, alcoholism, and stress response. Victims of drug-facilitated sexual assaults (DFSA) are understood to experience enhanced stress. At the Harris County Institute of Forensic Sciences (HCIFS), DFSA drug testing includes analysis of volatile compounds, ethanol, methanol, isopropanol, and acetone, by headspace gas chromatography/flame ionization detection. The prevalence of acetone-positive specimens in DFSA casework has been observed to exceed that of other human performance case types. In this report, DFSA cases received between 2019 and 2021 (n = 393) were reviewed and 41 acetone-positive cases were detailed. Overall, nearly 11% of the DFSA cases had acetone-positive blood or urine specimens, where 3% identified acetone only, 6% identified acetone and other drug(s), and 2% identified acetone, ethanol, and other drug(s). Acetone concentrations ranged from 0.010 to 0.147 g/100 mL in urine. Other drugs such as nor-carboxy-Δ9 -tetrahydrocannabinol, amphetamine, methamphetamine, ethanol, and benzoylecgonine were commonly detected. Elevated stress response encountered during DFSAs may facilitate the mechanism behind enhanced acetone production leading to increased identification. Limited availability of victim medical history precludes understanding the contribution of other disease states or physiological conditions. Nonetheless, the identification of acetone in DFSA specimens supports its potential as a biomarker of trauma in forensic toxicology casework and warrants future research within the community.

A Comparison of High Drug Concentrations in Impaired Driving and Postmortem Casework in Harris County, TX.

Drug-impaired driving is a growing public safety issue. Addressing impairment due to drugs other than ethanol can be challenging for forensic toxicologists as many factors need to be considered including the type of drug(s), drug-drug interaction, the dose(s) and the individual's physiological condition and drug use history. Interpretation of blood drug test results is additionally difficult as drug concentrations in impaired driving cases may overlap levels typically viewed as toxic. This study compares blood concentrations of drugs in impaired driving cases to those in postmortem cases in Houston, TX, from 2014 to 2020. Blood drug concentrations from driving while intoxicated (DWI) or driving under the influence of drugs (DUID) cases submitted to Houston Forensic Science Center (HFSC) and Harris County Institute of Forensic Sciences (HCIFS) were compared to postmortem blood test results from HCIFS. Eight DWI/DUID cases had drugs that exceeded impaired driving concentrations reported in the literature. These drugs included fentanyl (220 ng/mL), oxycodone (680 ng/mL), hydrocodone (310 and 490 ng/mL), clonazepam (330 ng/mL), methamphetamine (3,500 and 7,100 ng/mL) and tetrahydrocannabinol (THC) (160 ng/mL). For oxycodone and hydrocodone, the presented DWI/DUID cases exceeded 91% and 96% of postmortem concentrations, respectively. The 7,100 ng/mL methamphetamine DWI/DUID result was greater than 98% of postmortem cases. The presented DWI/DUID concentrations were higher than all but one postmortem case for clonazepam and higher than all postmortem cases for THC. This study demonstrates that extremely high drug concentrations in DWI/DUID casework blur the line between therapeutic/recreational and toxic concentrations.

Phenibut, a GABAB Agonist, Detected in a Fatality.

Phenibut, a GABAB agonist structurally similar to baclofen, is not approved for medical use in the United States, but is available through internet suppliers for recreational use. Calls to poison control centers for phenibut have increased over the last five years, and there are many case reports of severe acute intoxications and withdrawals requiring hospitalization. This case report describes the autopsy and toxicology findings of a 26-year-old male found dead at home with phenibut containers on scene. Autopsy findings and routine toxicology testing were generally unremarkable. Scene findings prompted the validation of a qualitative liquid chromatography tandem mass spectrometry method that confirmed the presence of phenibut in blood and urine.

Case Reports of Fatalities Involving Tianeptine in the United States.

Tianeptine is a tricyclic anti-depressant that is also known to have opioid receptor activity. We present two fatal cases of tianeptine intoxication in Texas in which tianeptine was used recreationally. The first case involved a 28-year-old white male found alone on the floor of his locked residence. He had a history of drug abuse but no other toxicological findings. The second case involved a 30-year-old white male found on the floor of the bathroom in his home. Drug paraphernalia and bags labeled as tianeptine powder were found at both scenes. In response to the first case, our laboratory developed a method for quantitation of tianeptine by LC-MS-MS. This method was then validated according to SWGTOX guidelines for specificity, calibration model, limit of detection, limit of quantitation, accuracy, precision, ion suppression, and carryover. This method was successfully used to determine tianeptine concentrations in postmortem blood in two cases. In these cases, tianeptine was measured at 2.0 mg/L and 8.4 mg/L. These represent the first known tianeptine fatalities in Texas and in the United States.

Physiological Regulation at 9 Months of Age in Infants Prenatally Exposed to Cigarettes.

The primary purpose of this study was to examine the association between prenatal cigarette exposure and physiological regulation at 9 months of age. Specifically, we explored the possibility that any association between prenatal cigarette exposure and infant physiological regulation was moderated by postnatal environmental tobacco smoke (ETS) exposure or infant gender. We evaluated whether male infants with prenatal cigarette exposure or infants who were also exposed to ETS after birth had the highest levels of physiological dysregulation. Respiratory sinus arrhythmia (RSA) was obtained from 206 (142 exposed and 64 nonexposed) infants during a baseline period and during procedures designed to elicit both positive and negative affect. There was a significant suppression of RSA during the negative affect task for nonexposed infants but not for exposed infants. Postnatal ETS exposure did not moderate this association; however, gender did moderate this association such that boys with prenatal cigarette exposure had a significant increase in RSA rather than the suppression seen among both nonexposed boys and girls. These results provide additional support for the idea that boys are particularly vulnerable to the effects of prenatal cigarette exposure.

Changes in smoking patterns during pregnancy.

This study examined trajectories of smoking during pregnancy among low-income smokers and differences on demographics, psychopathology, and smoking outcome expectancies among women with different smoking trajectories. The sample consisted of 215 urban pregnant smokers living in the United States. Results indicated four trajectories of smoking and significant changes over time within each trajectory. Persistent smokers had the highest demographic and mental health risks, reported higher craving compared to light smokers, and were more likely to endorse smoking to reduce negative affect, for state enhancement motives. Implications for intervention are discussed. The study was funded by the National Institute on Drug Abuse.

Anger, hostility, and aggression as predictors of persistent smoking during pregnancy.

OBJECTIVE: We examined the role of anger, hostility, and aggression, in addition to depression and stress, in predicting persistent smoking during pregnancy in a low-income sample. METHOD: The sample consisted of 270 pregnant women (189 smokers, 81 nonsmokers) recruited into a prospective study of prenatal cigarette exposure in the first trimester. Persistent pregnancy smoking was defined as self-reporting daily smoking in at least two trimesters, a positive salivary cotinine level in at least two trimesters, or infant meconium positive for nicotine and/ or its metabolites. RESULTS: Persistent smokers reported higher prenatal stress and negative affect symptoms (depression, anger, hostility, aggression) than nonpersistent smokers or nonsmokers. However, in the context of model testing, maternal anger, hostility, and aggression each accounted for unique variance in persistent smoking, whereas symptoms of depression and stress did not. CONCLUSIONS: To date, interventions for pregnant low-income smokers have been largely ineffective. The current results suggest that anger management interventions may be particularly effective for low-income persistent pregnant smokers and may be more likely to prevent relapse than depression-focused interventions.

Methadone, cocaine, opiates, and metabolite disposition in umbilical cord and correlations to maternal methadone dose and neonatal outcomes.

OBJECTIVES: The purpose was to explore methadone and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) umbilical cord disposition, correlate with maternal methadone dose and neonatal outcomes, and evaluate the window of drug detection in umbilical cord of in utero illicit drug exposure. METHODS: Subjects comprised 19 opioid-dependent pregnant women from 2 clinical studies, one comparing methadone and buprenorphine pharmacotherapy for opioid-dependence treatment and the second examining monetary reinforcement schedules to maintain drug abstinence. Correlations were calculated for methadone and EDDP umbilical cord concentrations and maternal methadone dose, and neonatal outcomes. Cocaine- and opiate-positive umbilical cord concentrations were compared with those in placenta and meconium, and urine specimens collected throughout gestation. RESULTS: Significant positive correlations were found for umbilical cord methadone concentrations and methadone mean daily dose, mean dose during the third trimester, and methadone cumulative daily dose. Umbilical cord EDDP concentrations and EDDP/methadone concentration ratios were positively correlated to newborn length, peak neonatal abstinence syndrome (NAS) score, and time-to-peak NAS score. Methadone concentrations and EDDP/methadone ratios in umbilical cord and placenta were positively correlated. Meconium identified many more cocaine- and opiate-positive specimens than did umbilical cord. CONCLUSIONS: Umbilical cord methadone concentrations were correlated to methadone doses. Also, our results indicate that methadone and EDDP concentrations might help to predict the NAS severity. Meconium proved to be more suitable than umbilical cord to detect in utero exposure to cocaine and opiates; however, umbilical cord could be useful when meconium is unavailable due to in utero or delayed expulsion.

Maternal methadone dose, placental methadone concentrations, and neonatal outcomes.

BACKGROUND: Few investigations have used placenta as an alternative matrix to detect in utero drug exposure, despite its availability at the time of birth and the large amount of sample. Methadone-maintained opioid-dependent pregnant women provide a unique opportunity to examine the placental disposition of methadone and metabolite [2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP)], to explore their correlations with maternal methadone dose and neonatal outcomes, and to test the ability to detect in utero exposure to illicit drugs. METHODS: We calculated the correlations of placental methadone and EDDP concentrations and their correlations with maternal methadone doses and neonatal outcomes. Cocaine- and opiate-positive placenta results were compared with the results for meconium samples and for urine samples collected throughout gestation. RESULTS: Positive correlations were found between placental methadone and EDDP concentrations (r=0.685), and between methadone concentration and methadone dose at delivery (r=0.542), mean daily dose (r=0.554), mean third-trimester dose (r=0.591), and cumulative daily dose (r=0.639). The EDDP/methadone concentration ratio was negatively correlated with cumulative daily dose (r=-0.541) and positively correlated with peak neonatal abstinence syndrome (NAS) score (r=0.513). Placental EDDP concentration was negatively correlated with newborn head circumference (r=-0.579). Cocaine and opiate use was detected in far fewer placenta samples than in thrice-weekly urine and meconium samples, a result suggesting a short detection window for placenta. CONCLUSIONS: Quantitative methadone and EDDP measurement may predict NAS severity. The placenta reflects in utero drug exposure for a shorter time than meconium but may be useful when meconium is unavailable or if documentation of recent exposure is needed.

Methadone disposition in oral fluid during pharmacotherapy for opioid-dependence.

INTRODUCTION: Oral fluid testing is widely used for detecting drug exposure, but data describing methadone and metabolites in oral fluid during pharmacotherapy for opioid-dependence are relatively limited. METHODS: 414 oral fluid specimens from 16 opioid-dependent pregnant women receiving daily methadone were analyzed for methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and methadol by liquid chromatography-mass spectrometry. RESULTS: All oral fluid specimens contained methadone greater than 1 ng/mL; 88% were positive for EDDP and 12% for methadol. Over 95% of oral fluid specimens exceeded the 20 ng/mL methadone cutoff set by the European Driving Under the Influence of Drugs, Alcohol and Medicines (DRUID) study. Methadone and EDDP oral fluid concentrations were highly variable within and between participants, did not predict methadone dose, but were negatively correlated with pH. CONCLUSION: Methadone was readily identified in oral fluid at concentrations greater than 20 ng/mL following daily 30-110 mg/day methadone pharmacotherapy. As no specimens contained only EDDP or methadol, there was no advantage to including these analytes for identification of methadone exposure. As nearly all oral fluid specimens from methadone-maintained patients exceeded the DRUID guideline, the 20 ng/mL cutoff appears to be sensitive enough to detect daily methadone exposure; however, additional indicators of behavioral and/or motor impairment would be necessary to provide evidence of driving impairment.

Prenatal methadone exposure, meconium biomarker concentrations and neonatal abstinence syndrome.

AIMS: Methadone is standard pharmacotherapy for opioid-dependent pregnant women, yet the relationship between maternal methadone dose and neonatal abstinence syndrome (NAS) severity is still unclear. This research evaluated whether quantification of fetal methadone and drug exposure via meconium would reflect maternal dose and predict neonatal outcomes. DESIGN: Prospective clinical study. SETTING: An urban drug treatment facility treating pregnant and post-partum women and their children. PARTICIPANTS: Forty-nine opioid-dependent pregnant women received 30-110 mg methadone daily. MEASUREMENTS: Maternal methadone dose, infant birth parameters and NAS assessments were extracted from medical records. Thrice-weekly urine specimens were screened for opioids and cocaine. Newborn meconium specimens were quantified for methadone, opioid, cocaine and tobacco biomarkers. FINDINGS: There was no relationship between meconium methadone concentrations, presence of opioids, cocaine and/or tobacco in meconium, maternal methadone dose or NAS severity. Opioid and cocaine were also found in 36.7 and 38.8 of meconium specimens, respectively, and were associated with positive urine specimens in the third trimester. The presence of opioids other than methadone in meconium correlated with increased rates of preterm birth, longer infant hospital stays and decreased maternal time in drug treatment. CONCLUSIONS: Methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) concentrations in meconium did not predict infant birth parameters or NAS severity. Prospective urine testing defined meconium drug detection windows for opiates and cocaine as 3 months, rather than the currently accepted 6 months. The presence of opioids in meconium could be used as a biomarker for infants at elevated risk in the newborn period.

High-throughput simultaneous analysis of buprenorphine, methadone, cocaine, opiates, nicotine, and metabolites in oral fluid by liquid chromatography tandem mass spectrometry.

A method for simultaneous determination of buprenorphine (BUP), norbuprenorphine (NBUP), methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), cocaine, benzoylecgonine (BE), ecgonine methyl ester (EME), anhydroecgonine methyl ester (AEME), morphine, codeine, 6-acetylmorphine (6AM), heroin, 6-acetylcodeine (6AC), nicotine, cotinine, and trans-3'-hydroxycotinine (OH-cotinine) by liquid chromatography tandem mass spectrometry in oral fluid (OF) was developed and extensively validated. Acetonitrile (800 µL) and OF (250 µL) were added to a 96-well Isolute-PPT+protein precipitation plate. Reverse-phase separation was achieved in 16 min and quantification was performed by multiple reaction monitoring. The assay was linear from 0.5 or 1 to 500 µg/L. Intraday, interday, and total imprecision were less than 13% (n = 20), analytical recovery was 92-114% (n = 20), extraction efficiencies were more than 77% (n = 5), and process efficiencies were more than 45% (n = 5). Although ion suppression was detected for EME, cocaine, morphine, 6AC, and heroin (less than 56%) and enhancement was detected for BE and nicotine (less than 316%), deuterated internal standards compensated for these effects. The method was sensitive (limit of detection 0.2-0.8 µg/L) and specific (no interferences) except that 3-hydroxy-4-methoxyamphetamine interfered with AEME. No carryover was detected, and all analytes were stable for 24 h at 22 °C, for 72 h at 4 °C, and after three freeze-thaw cycles, except cocaine, 6AC, and heroin (22-97% loss). The method was applied to 41 OF specimens collected throughout pregnancy with a Salivette® OF collection device from an opioid-dependent BUP-maintained pregnant woman. BUP ranged from 0 to 7,400 µg/L, NBUP from 0 to 71 µg/L, methadone from 0 to 3 µg/L, nicotine from 32 to 5,020 µg/L, cotinine from 125 to 508 µg/L, OH-cotinine from 11 to 51 µg/L, cocaine from 0 to 419 µg/L, BE from 0 to 351 µg/L, EME from 0 to 286 µg/L, AEME from 0 to 7 µg/L, morphine from 0 to 22 µg/L, codeine from 0 to 1 µg/L, 6AM from 0 to 4 µg/L, and heroin from 0 to 2 µg/L. All specimens tested negative for EDDP and 6AC. This method permits a fast and simultaneous quantification of 16 drugs and metabolites in OF, with good selectivity and sensitivity.

Identifying prenatal cannabis exposure and effects of concurrent tobacco exposure on neonatal growth.

BACKGROUND: Cannabis is the most frequently used illicit drug among pregnant women, but data describing the effects of prenatal cannabis exposure and concurrent nicotine and cannabis exposures on neonatal growth are inconsistent. Testing of meconium, the first neonatal feces, offers objective evidence of prenatal cannabis exposure, but the relative ability of meconium testing and maternal self-report to identify affected neonates remains unclear. METHODS: Eighty-six pregnant women provided detailed self-reports of daily cannabis and tobacco consumption throughout pregnancy. Cannabinoids and tobacco biomarkers were identified in oral fluid samples collected each trimester and quantified in meconium at birth. RESULTS: Cannabis-using women were significantly more likely to also consume tobacco, and smoked similar numbers of cigarettes as non-cannabis-using tobacco smokers. As pregnancy progressed, fewer women smoked cannabis and those who continued to use cannabis reported smoking a smaller number of cannabis joints, but positive maternal oral fluid tests cast doubt on the veracity of some maternal self-reports. More neonates were identified as cannabis exposed by maternal self-report than meconium analysis, because many women quit cannabis use after the first or second trimester; meconium was more likely to be positive if cannabis use continued into the third trimester. Cannabis exposure was associated with decreased birth weight, reduced length, and smaller head circumference, even after data were controlled for tobacco coexposure. CONCLUSIONS: Prenatal cannabis exposure was associated with fetal growth reduction. Meconium testing primarily identifies prenatal cannabis exposure occurring in the third trimester of gestation.

Effect of hydrolysis on identifying prenatal cannabis exposure.

Identification of prenatal cannabis exposure is important due to potential cognitive and behavioral consequences. A two-dimensional gas chromatography-mass spectrometry method for cannabinol, Delta(9)-tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), 8beta,11-dihydroxy-THC, and 11-nor-9-carboxy-THC (THCCOOH) quantification in human meconium was developed and validated. Alkaline, enzymatic, and enzyme-alkaline tandem hydrolysis conditions were optimized with THC- and THCCOOH-glucuronide reference standards. Limits of quantification ranged from 10 to 15 ng/g, and calibration curves were linear to 500 ng/g. Bias and intra-day and inter-day imprecision were <12.3%. Hydrolysis efficiencies were analyte-dependent; THC-glucuronide was effectively cleaved by enzyme, but not base. Conversely, THCCOOH-glucuronide was most sensitive to alkaline hydrolysis. Enzyme-alkaline tandem hydrolysis maximized efficiency for both glucuronides. Identification of cannabinoid-positive meconium specimens nearly doubled following alkaline and enzyme-alkaline hydrolysis. Although no 11-OH-THC glucuronide standard is available, enzymatic hydrolysis improved 11-OH-THC detection in authentic specimens. Maximal identification of cannabis-exposed neonates and the widest range of cannabis biomarkers are achieved with enzyme-alkaline tandem hydrolysis.

Nicotine and metabolites in meconium as evidence of maternal cigarette smoking during pregnancy and predictors of neonatal growth deficits.

INTRODUCTION: Many women continue tobacco use during pregnancy despite known adverse consequences on neonatal growth and development. Testing meconium, the first neonatal feces, for tobacco biomarkers offers objective evidence of prenatal tobacco exposure. However, relationships between the amount, frequency, and timing of cigarette smoking during gestation and tobacco biomarker meconium concentrations and neonatal outcomes are unclear. METHODS: Eighty-seven pregnant women provided detailed self-reports of daily tobacco consumption throughout pregnancy. Nicotine, cotinine, and trans-3'-hydroxycotinine were quantified in neonatal meconium by liquid chromatography-tandem mass spectrometry. RESULTS: Among nonsmokers, all meconium specimens were negative, whereas nearly all meconium specimens were positive if the mother self-reported tobacco use into the third trimester. Tobacco biomarker concentrations were significantly albeit weakly correlated with mean cigarettes per day in the third trimester. Reduced birth weight, gestational age, or head circumference were observed if meconium contained one or more tobacco biomarkers, but deficits did not correlate with biomarker concentrations. CONCLUSION: While previously thought to reflect second and third trimester drug exposure, meconium appears to reliably identify only third trimester drug use. While a 10 ng/g nicotine, cotinine, or trans-3'-hydroxycotinine cutoff in meconium was previously proposed to differentiate tobacco-exposed from nonexposed or passively exposed neonates, improved maternal self-reporting techniques in this cohort suggest that a lower cutoff, equivalent to the analytic limits of quantification, is more appropriate.

New meconium biomarkers of prenatal methamphetamine exposure increase identification of affected neonates.

BACKGROUND: Prenatal methamphetamine (MAMP) exposure is poorly reflected in neonatal meconium. Often, maternal self-reported MAMP use is not corroborated by positive results in amphetamines immunoassays of meconium, and even if initial test results are positive, they frequently are not confirmed for MAMP or amphetamine (AMP) by chromatographic analysis. The presence of the MAMP metabolites p-hydroxymethamphetamine (pOHMAMP), p-hydroxyamphetamine (pOHAMP), and norephedrine (NOREPH) in meconium may improve the identification of MAMP- and AMP-exposed neonates. METHODS: Immunoassay-positive and -negative meconium samples were subjected to liquid chromatography- tandem mass spectrometric reanalysis for these recently identified metabolites. RESULTS: pOHAMP and NOREPH were detected only when MAMP and/or AMP were present and thus do not appear to be promising biomarkers of prenatal MAMP exposure. pOHMAMP, in contrast, identified 6 additional neonates whose mothers reported MAMP exposure, yet had a meconium sample screened as negative; pOHMAMP was more likely to be present if maternal MAMP use continued into the third trimester. Although the pOHMAMP results for meconium samples corroborated the maternal self-reports, the confirmation rate for positive meconium screening results did not improve with the inclusion of these new biomarkers. CONCLUSIONS: pOHMAMP identified additional MAMP- exposed neonates; therefore, MAMP, AMP, and pOHMAMP should be included in meconium chromatographic analyses. Maximizing the identification of MAMP-exposed children requires improvement in immunoassay screening tests to reduce false-negative and false-positive results. Additional research will help clarify which AMP-related compounds, if any, contribute to unconfirmed positive results in screening tests. Furthermore, nonamphetamine compounds endogenous to the complex meconium matrix also may cross-react, making chromatographic confirmation of screening results essential.

Identification of prenatal amphetamines exposure by maternal interview and meconium toxicology in the Infant Development, Environment and Lifestyle (IDEAL) study.

The Infant Development Environment and Lifestyle study is investigating the effects of prenatal methamphetamine (MAMP) exposure on infant and child development; potential concurrent exposure to cannabis and tobacco also are evaluated. Maternal self-reported drug use and/or meconium toxicology results defined drug exposure status. It is unclear how the frequency, duration, and magnitude of maternal MAMP exposure affect qualitative and quantitative meconium results. Interviews regarding maternal drug use were collected shortly after birth; meconium specimens were screened for amphetamines, cannabis, and cotinine by immunoassay and confirmed by gas chromatography mass spectrometry. The majority of MAMP- and cannabis-exposed infants were identified by maternal interview alone. Meconium tests were more likely to be positive if the mother reported MAMP and cannabis use, particularly in the third trimester. Less than half of immunoassay-positive amphetamines (31.0%) and cannabis (17.9%) meconium results were confirmed by gas chromatography mass spectrometry. Tobacco exposure was equally detected by immunoassay cotinine screening and maternal report. Meconium concentrations did not correlate with maternal self-report status or trimester of use or frequency or route of MAMP use. Maternal self-report was more sensitive than meconium testing for identifying MAMP and cannabis-exposed neonates; however, the timing of drug exposure may influence meconium toxicology results. Most women stopped MAMP and cannabis use before the third trimester. In the first trimester, meconium has not yet formed, and based on our recent results for opiates and cocaine, drug use in the second trimester appears to be poorly reflected in meconium. Low confirmation rates in meconium reinforce the need for confirmatory testing following positive screening results and additional research to identify alternative biomarkers.