PEth Resources

The collection supplies that we have are not CLIA-waived, as we are a CLIA accredited laboratory and must follow all accreditation standards.

There are no other labs that do commercial dried blood spot PEth testing, so there are no labs for comparison.

No. The results of any second collected specimen have absolutely no bearing on the validity of the results of the first collected specimen. Furthermore, each matrix has its own advantages, disadvantages and limits of interpretation.

The literature suggests that it requires multiple servings of ethanol on a single occasion to produce a positive PEth result. PEth has a half-life of approximately 4.5 days.

There are zero instances in the scientific literature (over 25,000 articles) of anything other than consumption of ethanol creating Peth results.

Yes, during your account setup process just inform us that you will only need the blood spot cards.

We do not sell collection supplies. All account set-up paperwork must be completed before we ship the supplies to your facility.

Whole blood can be submitted for PEth testing by sending in the whole blood tube. We do not recommend transferring blood collected under a chain of custody via venipuncture to a dried blood spot card.

We are not able to help with any of the shipping coordination or additional questions regarding international testing as we do not know the local laws.

No. Chain of Custody Forms are not used for research specimens.

A manifest form is required in this case. Identification numbers and dates are required on the manifest. Click here to see a sample manifest form.

Please note that:

• ID numbers on the manifest must match the ID on the specimens.
• 2 unique numbers are preferred, if not possible, one unique number is acceptable.

No, the sample may be shipped ambient.

No, Lidocaine will NOT explain a GCMS or LCMSMS confirmed positive cocaine or cocaine metabolite in any specimen type (blood, urine, hair, nails, meconium, umbilical cord segment, etc…). The compounds are very structurally different and breakdown into very different metabolites.

Yes, the results can be different. Each specimen type has its own advantages, disadvantages, threshold to positivity, and detection time window. One test does not refute the other. The test results are cumulative. For instance, if the maternal urine is positive for cocaine and newborn meconium is positive for methamphetamine, the results do not rule each other out. The appropriate interpretation is that the mother consumed both cocaine and methamphetamine.

Yes, the analysis of a number of tissue types for the presence of drugs of abuse has been used in every state for decades. Specifically, our umbilical cord testing has been used to provide evidence of drug use by the mother in numerous states. Additionally, the detection of drug in umbilical cord was used as evidence of maternal drug consumption in a murder case in South Carolina and that interpretation was upheld on appeal to the SC Supreme Court.

Extensive research has helped create a good understanding of PEth and how it can be utilized both in research and commercially. This has helped eliminate major challenges that other, less researched assays, might face.

Recent studies have indicated that low-level positive EtG results can be produced by certain agents like hand sanitizers and mouth wash (incidental exposure). Research indicates that the volume of alcohol required to trigger a positive PEth result is far above the level available from incidental exposure.

The testing can only detect whether PEth is present in the specimen, it cannot determine time, dose, or frequency of use. The literature suggests that it requires multiple servings of ethanol on a single occasion to produce a positive PEth result.

5 individual large drops on a dried blood spot collection card or 5 milliliters of whole blood collected in a gray-top collection tube containing anticoagulant.

There are too many variables for anyone to know time of use, dosage, or frequency from the result(s) of a drug test. Reservoir matrices such as hair, fingernail, umbilical cord, and meconium continuously collect drug and alcohol biomarkers. This makes it difficult to determine specific details of use. Because the biomarker is collected over a period of time, the results represent total accumulation that cannot be pin-pointed to specific times/dates/dosages, etc.

Yes, the price is the same whether it is whole blood or dried blood spot.

Testing can only detect whether PEth is present in the specimen, it cannot determine time, dose, or frequency of use. PEth has a half-life of 4.5 days so the results are contingent on when the donor last drank and how much they have been drinking.

You may use any shipping courier of your choice.

With strictly research specimens, our laboratory has more flexibility regarding testing timeframes. In general, specimens should not be tested beyond their stated timeframe for stability. The Sponsor should note that any results from testing specimens beyond their stated timeframe for stability can be less reliable.

No. When testing a reservoir specimen type, a specimen type where analytes tend to accumulate, you may not backtrack to determine time, dosage, or frequency. The result is positive or negative for the appropriate detection window associated with the specimen type.

Please keep specimens at the normal air-conditioned lab temp ±26 degrees Celsius or in the fridge.

A positive PEth result means that the donor has consumed ethanol sometime during the last 2-4 weeks (approximately).

• 2 blood spot lancets
• 2 tamper-evident seal
• 2 non-ethanol based alcochol pads
• 1 blood spot card
• 1 blood spot drying box

• Room Temp = 1 year
• Refrigerated = 1 year
• Frozen = 1 year at 20ºC (-4ºF)

Dried blood spot cards can be stored up to 1 year at room temperature, refrigerated, or frozen. Whole blood tubes can be stored for 1 week at room temperature, 1 week refrigerated, or up to 1 year frozen (can be thawed up to 3 times).

The Peth test is designed to detect heavy drinking up to approximately 2-4 weeks prior to collection. This is because PEth has an average half-life is 4.5 days. This means that every 4.5 days the level of Peth is cut in half. For example: If an average person with a PEth level of 1000 ng/mL stops drinking, it would take approximately 2.5 weeks for them to fall below the 20 ng/mL cut-off level.

Please send at least 10 or more specimens per batch; preferably overnight with tracking capability. You can use any courier of your choice. Please have specimens arrive at USDTL between Monday and Friday.

Up to approximately 2-4 weeks depending on the starting concentration of PEth.

ONLY use isopropyl alcohol wipes. DO NOT use any wipes or sanitizers that contain ethyl alcohol.

Our PEth testing in dried blood spots measures the 16:0/18:1 PEth species.

There are several explanations for this.

1. 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.
2. 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.
3. 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.
4. Lastly, some placentas can prevent some compounds from reaching the fetus. There are documented cases of maternal ingestion without in utero exposure.

We typically use 2-3 of the blood spots for testing (assuming all five circles are filled). Ideally, there will be 1-2 blood spots left over and stored in the event a retest is requested.