To view the Hair Testing Panels and Collection Instructions, click here.
USDTL Hair Test In the News
Quantity Not Sufficient 11-Nov-2016
The Long Game 02-Feb-2015
Hair Ethyl Glucuronide: Uses and Implications 01-Apr-2013
The Stability of Drugs in Hair 01-Oct-2012
USDTL Hair Research
Hair Poster Presentations
Detection of Trace Naltrexone and 6β-Naltrexol in Human Hair Using Enzyme Linked Immunosorbent Assay (ELISA)
Detection of Trace Buprenorphine and Norbuprenorphine in Human Hair Using Enzyme-Linked Immunosorbent Assay (ELISA)
USDTL Assisted Hair Research
Foundational Hair Research
Hair White Papers
Annotated Bibliography for EtG in hair 20-Mar-2014
Hair Slide Presentations
THC in Hair
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.
Des Plaines, IL - United States Drug Testing Laboratory, Inc. (USDTL), a forensic laboratory specializing in drug and alcohol testing using advanced specimens, has released a new assay to detect zolpidem (Ambien®) use in fingernail and hair specimens. Previously available only in urine and oral-fluid specimens, zolpidem testing in fingernails and hair offers forensic drug testing professionals new, powerful tools to meet their drug testing needs.
*Click the green and white plus sign beside each question to view the answer.
Can a hair test be manipulated by the donor?
Can a hair test be used to prove that a previously taken urine test was inaccurate?
Can a hair test determine how much or how often someone is using a drug?
Can someone test positive in hair because of passive or environmental exposure?
Does race make a difference in hair testing results?
How can positive drug or alcohol test results be interpreted? If the quantity of drug or alcohol metabolite detected is high could that be an indication that the donor (1) was consuming a large amount, (2) was using recently, or (3) was using frequently?
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.
How long can drugs be detected in body hair?
How long can drugs be detected in head hair?
Q: Why are both ethyl sulfate (EtS) and ethyl glucuronide (EtG) included in urine testing for alcohol use, but only EtG in fingernail or hair testing?
A: For urine testing, it is standard practice in the field of toxicology to include both EtS and EtG, because EtG is subject to bacterial production and degradation if a urine sample is contaminated (e.g. when the donor has a urinary tract infection). EtS is not subject to bacterial production or degradation, and provides a second, more reliable alcohol biomarker in these urine contamination scenarios. Other specimens types, such as fingernails and hair, do not have this issue, so only EtG is measured in those sample types.
What does a positive hair test result mean?
Why do we test for EtG in hair and not FAEE?
Why was one matrix positive and another negative on the same donor?