What the lab can and cannot do: clinical interpretation of drug testing results.

Urine drug testing is one of the objective tools available to assess adherence. To monitor adherence, quantitative urinary results can assist in differentiating "new" drug use from "previous" (historical) drug use. "Spikes" in urinary concentration can assist in identifying patterns of drug use.

Prevalence of Fetal Alcohol Exposure by Analysis of Meconium Fatty Acid Ethyl Esters; A National Canadian Study.

Our study aimed to estimate the prevalence of heavy fetal alcohol exposure through the analysis of meconium FAEEs as an objective biomarker of fetal exposure. We conducted a study on meconium samples collected nationwide through the Maternal-Infant Research on Environmental Chemicals (MIREC) Study Group. FAEE in meconium was quantified by an established headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME GC-MS).

Association of In Utero Exposure to Polybrominated Diphenyl Ethers With the Risk of Hypospadias.

Importance: Polybrominated diphenyl ethers (PBDEs) are added to many consumer products as flame retardants, and their endocrine-disrupting properties are a growing health concern in pregnancy.

Objective: To investigate whether in utero PBDE exposure as measured in maternal hair is associated with increased risk for hypospadias.

Design, Setting, And Participants: In this case-control study, the setting was the urology clinic of a tertiary pediatric hospital between January 3, 2011, and April 1, 2013.

FASD: folic acid and formic acid - an unholy alliance in the alcohol abusing mother.

Alcohol consumption during pregnancy remains a significant cause of preventable birth defects and developmental disabilities; however, the mechanism of toxicity remains unclear. Methanol is present as a congener in many alcoholic beverages and is formed endogenously. Because ethanol is preferentially metabolized over methanol, it has been found in the sera and cerebro-spinal fluid of alcoholics.

Folate status of women in Toronto: Implications of folate fortification and supplementation.

Objectives: To assess the percentage of women of childbearing age with suboptimal levels of folate for protecting against neural tube defects (<906 nM), and assess folate status among the elderly.

Methods: A total of 1,035 anonymous blood samples from a centralized clinical laboratory, with a catchment area across the Greater Toronto Area, were assessed for red blood cell (RBC) folate concentrations using a chemiluminescent immunoassay. Folate analysis was requested by physicians as part of clinical care.

Pharmacogenetics of chronic pain management.

Objective: The experience of chronic pain is one of the commonest reasons individuals seek medical attention, making the management of chronic pain a major issue in clinical practice. Drug metabolism and responses are affected by many factors, with genetic variations offering only a partial explanation of an individual's response. There is a paucity of evidence for the benefits of pharmacogenetic testing in the context of pain management.

Folic acid transport to the human fetus is decreased in pregnancies with chronic alcohol exposure.

Background: During pregnancy, the demand for folic acid increases since the fetus requires this nutrient for its rapid growth and cell proliferation. The placenta concentrates folic acid into the fetal circulation; as a result the fetal levels are 2 to 4 times higher than the maternal level. Animal and in vitro studies have suggested that alcohol may impair transport of folic acid across the placenta by decreasing expression of transport proteins.

False-positive meconium test results for fatty acid ethyl esters secondary to delayed sample collection.

Background: Meconium analysis for fatty acid ethyl esters (FAEEs) is a validated method for identifying heavy prenatal ethanol (EtOH) exposure. This study investigated whether delayed sample collection can result in false-positive test results for FAEEs because of collection of samples potentially contaminated with postnatally produced stool.

Methods: Serial excretions were prospectively collected from neonates born to nondrinking mothers to capture the transition from meconium to postnatal stool.

Methadone: a review of drug-drug and pathophysiological interactions.

Numerous established and potential drug interactions with methadone are clinically important in people treated with methadone either for addiction or for chronic pain. Methadone users often have comorbidities and are prescribed drugs that may interact with methadone. Methadone is extensively metabolized by cytochrome P450 (CYP) 3A4 and to a lesser extent by CYP 1A2, 2D6, 2D8, 2C9/2C8, 2C19, and 2B6.

Folate fortification and supplementation--are we there yet?

Background: Folic acid fortification of flour has significantly decreased the incidence of neural tube defects (NTDs). We aimed at examining whether Ontario women of child-bearing age exhibit protective levels of RBC folate.

Methods: We reviewed laboratory databases on RBC folic acid from pre and post fortification years.

Formic acid, a novel metabolite of chronic ethanol abuse, causes neurotoxicity, which is prevented by folic acid.

Background: Methanol is endogenously formed in the brain and is present as a congener in most alcoholic beverages. Because ethanol is preferentially metabolized over methanol (MeOH) by alcohol dehydrogenase, it is not surprising that MeOH accumulates in the alcohol-abusing population. This suggests that the alcohol-drinking population will have higher levels of MeOH's neurotoxic metabolite, formic acid (FA).

Toxicology: then and now.

Toxicology is "the science of poisons"; more specifically the chemical and physical properties of poisons, their physiological or behavioral effects on living organisms, qualitative, and quantitative methods for their analysis and the development of procedures for the treatment of poisoning. Although the history of poisons dates to the earliest times, the study and the science of toxicology can be traced to Paracelsus (1493-1541) and Orfila (1757-1853). Modern toxicology is characterized by sophisticated scientific investigation and evaluation of toxic exposures.