To view the PEth Testing Panels and Collection Instructions, click here.
USDTL PEth Test In the News
Monitoring Alcohol Use Among Pregnant Women 11-Nov-2016
Breaking the Blood Barrier 01-Dec-2015
A Moment In Time 02-Feb-2015
Made In The Blood 02-Feb-2015
The Long Game 02-Feb-2015
USDTL PEth Research
PEth Poster Presentations
Assessment of Maternal Drinking Patterns from Self-Report Screening and Two Direct Alcohol Biomarkers in Newborns
Prevalence Rates of Prenatal Alcohol Exposure From Detection of Phosphatidylethanol in Dried Blood Spots
The Collection of Umbilical Cord Blood on Filter Paper Cards for Detection of Phosphatidylethanol in Newborns at Risk for Prenatal Alcohol Exposure
Development and Validation of a Robust LC-MSMS Method for the Fast Quantitation of Phosphatidylethanol
The Increased Sensitivity of Phosphatidylethanol Over Fatty Acid Ethyl Esters in Identifying Neonates Exposed to Dangerous Level of Alcohol In Utero
USDTL Assisted PEth Research
PEth White Papers
Annotated Bibliography for PEth 16-Apr-2014
Effective July 18, 2016, USDTL will be implementing a new way of reporting quantitative results. In order to satisfy accreditation requirement, the concentrations of drugs exceeding the Upper Limit of Quantification (ULOQ) for any given drug will be reported as > ULOQ (greater than ULOQ). The ULOQ will be provided.
Quantity Not Sufficient (QNS) is a result of not having a sufficient quantity (volume) of
specimen to test for the panels ordered. The amount of specimen required for collection
is directly related to the amount of specimen needed to screen and confirm for the panels we offer. The initial screening uses a portion of the original specimen and the confirmation testing uses another portion of the original specimen. To forensically confirm positives, means running a new test, with a new portion of the original specimen, using a different analytical technique.
It is our first priority to deliver testing results that provide the most valuable information possible for your substance abuse testing needs. To better accomplish this duty to our clients, we are updating our policy concerning specimens that do not have sufficient volume for both preliminary testing and confirmation. Effective April 1, 2015, confirmatory tests that cannot be completed due to insufficient specimen volume will be canceled on an individual drug class and/or analyte basis. We will report confirmation results for each test for which there is sufficient volume of specimen available, giving you access to more information.
USDTL researchers will investigate the relationship between in utero alcohol exposure and epigenetics using Small Business Innovation Research funding from the National Institute on Alcohol Abuse and Alcoholism.
USDTL is the first laboratory to be awarded specimens from the Virtual Repository of Dried Blood Spots, a new national database of dried blood spot specimens available for use in research.
*Click the green and white plus sign beside each question to view the answer.
Can we use any tube for whole blood collection?
Please use only purple, gray, and green top tubes.
Do we need to spin (centrifuge) whole blood samples?
How do PEth results differ from Urine EtG/EtS results?
How much blood is required for a PEth testing sample?
5 individual large drops on a collection card.
How much blood is required for whole blood testing?
Requested sample volume is 5 milliliters.
What is the window of detection for PEth?
What is the window of detection for whole blood testing?
Whole blood testing for substances of abuse identifies usage over a 2-3 day period.
When will I receive whole blood testing results?
Which phosphatidylethanol species do you measure during PEth testing?
Our PEth testing in dried blood spots measures the 16:0/18:1 PEth species.
Why was one matrix positive and another negative on the same donor?
There are several explanations for this.
- Different sample matrices have different detection time frames. The result of any second collected specimen has no bearing on the validity of a first collected specimen. For example, a hair sample with a three month window of detection might test positive for a particular substance, while a urine sample from the same donor, with a 2-3 day window of detection, might test negative. In this case, the donor has used that substance within the past three months, but may not have used it within the most recent three days.
- The result of any second collected specimen has no bearing on the validity of a first collected specimen. Therefore, a negative result observed for the umbilical cord does not refute a positive result observed on the maternal urine specimen and the reverse is true as well. There are many legitimate reasons for discrepant urine and umbilical cord results.
- The urine specimen was a screen only result and was not confirmed using an appropriate mass spectrometric method. The screen only urine result is a clinically valid result, however, without an appropriate mass spectrometric confirmation, the urine result has no value in a forensic proceeding.
- Lastly, some placentas can prevent some compounds from reaching the fetus. There are documented cases of maternal ingestion without in utero exposure.