Adult & Child Drug Testing Lab

Fingernail Drug Testing

Highly stable, simple to collect, and easy to ship and store, fingernails provide a test sample that is at the cutting edge of drug and alcohol testing. Fingernails are made up of keratin, the same material that hair is made of. As the nail grows, substances can pass from the blood vessels below the nail into the keratin fibers where they become trapped. Fingernails are four times thicker than the typical strand of hair and often capture more of a substance than hair can. Biomarkers become locked in keratin fibers along the entire length of the nail, and can be detected up to 3-6 months after drug or alcohol abuse. Environmental exposure to illicit substances can be detected immediately in nail samples. When drugs or alcohol are ingested, biomarkers can be found in nails as early as 1-2 weeks after. The time period during which drug or alcohol ingestion can be detected depends on the substance used, the amount used, and personal metabolism. Fingernail samples are clipped and collected by the donor in front of a trained collection staff member. A clipping of 2-3 mm long (about the width of a quarter) from all ten fingernails will give about 100 mg of sample, the ideal amount for screening and confirmation. Larger profiles may require more. We recommend weighing the specimen on a jeweler's scale.

Click here to view our fingernail collection instruction slides.

Click here to download the fingernail and hair drug panels.

Click here to view the Fingernail Resources page.

Drug Panels

  • 17 Panel
  • 16 Panel
  • 15 Panel
  • 14 Panel
  • 12 Panel
  • 10 Panel
Amphetamines
amphetamine, MDA, MDEA, MDMA, methamphetamine
Cannabinoids
carboxy-THC, native-THC
Cocaine
benzoylecgonine, cocaethylene, cocaine, norcocaine
Opiates
6-MAM, codeine, hydrocodone, hydromorphone, morphine, oxymorphone, oxycodone
Phencyclidine
phencyclindine (PCP)
Benzodiazepines
alprazolam, diazepam, midazolam, nordiazepam, oxazepam, temazepam
Barbiturates
amobarbital, butalbital, pentobarbital, phenobarbital, secobarbital
Methadone
EDDP, methadone
Propoxyphene
propoxyphene, norpropoxyphene
Oxycodone
oxycodone, oxymorphone
Meperidine
normeperidine
Tramadol
tramadol
Fentanyl
norfentanyl
Sufentanil
norsufentanil
Ketamine
ketamine, norketamine
Buprenorphine
buprenorphine, norbuprenorphine
Zolpidem
zolpidem (e.g. Ambien®)
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*Click the green and white plus sign beside each drug class to view the substances within each class.
Add-Ons Available
Buprenorphine
buprenorphine, norbuprenorphine
Diphenhydramine
diphenhydramine
High-Potency Opioids (HPOs)
6-β-Naltrexol (naltrexone metabolite), butorphanol (e.g. Stadol®), nalbuphine (e.g. Nubain®), naloxone (e.g. Narcan®), naltrexone (e.g. Revia®)
EtG (Direct Ethanol Biomarker)
ethyl glucuronide
Propofol Glucuronide
propofol glucuronide (e.g. Diprivan®)
Zolpidem
zolpidem (e.g. Ambien®)
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Collection

Collection Instructions
Collection Steps
Prior to collection
Prior to each collection, wipe the clippers with a non-ethanol based alcohol pad.
Have the donor wash their hands and remove dirt from nails
Have the donor wash their hands with soap and water prior to specimen collection. Remove dirt from the nails.
The nails should look like natural nails and must not have an unusual appearance
The nails should look like natural nails and must not have an unusual appearance. Nails must be clear of any substances including but not limited to: cosmetic treatments (e.g. polish, artificial acrylic, gel or silk overlay), non-cosmetic substances (e.g. dirt, substance residue oils, stains, inks or dyes, etc.). When removing fingernail polish prior to collection, a non-ethanol based polish remover such as isopropyl alcohol or acetone should be used. If the nail does not look like natural nail or has an unusual appearance for any reason, do not collect the nail.
Verify the donor’s identity
Verify the donor’s identity with a government-issued photo ID.
On the Custody and Control Form do the following
On the Custody and Control Form do the following:
A. Once verified, mark the Picture ID Verified box on the Custody and Control Form.
B. Record the donor’s ID number. This may be the Social Security number, Driver’s License number, Medical Record number, Employee number or any other number of your facilities choosing.
C. Record the donor’s name (optional).
D. Mark the specimen matrix and location.
E. Mark the appropriate reason for testing.
F. Mark the panel ordered for this collection.
G. Record the Collection Site Facility information if it is different than the Account Information at the top of the form.
Open the collection supplies
Open the collection supplies in the presence of the donor.
Have the donor clip their nails
Have the donor clip their nails as close to the nail bed as comfortable. It is recommended to clip over a new, plain sheet of paper to capture the clippings.
Fold each side of the collection foil up to form a tray
Fold each side of the collection foil up to form a tray. Once clipping is complete, pour the nails from the sheet of paper into the foil tray.
Fold each side of tray inward and place in specimen collection envelope
Once the required amount of specimen is collected, fold each side of the foil tray inward to secure the nails and place the folded foil into the specimen collection envelope.
Write the Donor ID on the envelope
Write the Donor ID from the Custody and Control Form on the envelope in the Test Subject ID section.
Place the long bar-coded specimen seal
Place the long bar-coded specimen seal from the Custody and Control form across the bottom of the envelope. Make sure the sticker seals the flap of the envelope securely.
Have the donor read and initial
Have the donor read and initial the first sentence on the envelope, and date and initial the bar-coded specimen seal where Donor Initials is indicated.
The collector reads, dates and signs
The collector then reads, dates and signs the second sentence of the envelope and records the specimen weight, if available.
The donor and collector should both confirm
The donor and collector should both confirm that the Test Subject ID Number on the envelope matches the Donor ID number on the Custody and Control Form and that the Control Number from the bar-coded sticker on the envelope matches the Control Number on the Custody and Control Form.
Date, sign and print the collector name
Date, sign and print the collector name in Step 4 of the Custody and Control Form.
Have the donor date, print and sign their name
Have the donor date, print and sign their name in Step 5 of the Custody and Control Form (optional).
In the presence of the donor, place the top copy
In the presence of the donor, place the top copy of the Custody and Control Form in the outer pocket of the security bag. Place the envelope in the other pocket of the security bag and seal the bag. The additional copies of the Custody and Control Form can be distributed at the discretion of the collecting facility.
Place the specimen envelope
Place the specimen envelope in an appropriate specimen transport overwrap and contact your courier for pick-up.
Client Services

By Phone: 1.800.235.2367

Business Hours (CST)

Monday 6am - 8pm
Tuesday 6am - 8pm
Wednesday 6am - 8pm
Thursday 6am - 8pm
Friday 6am - 8pm

Contact Client Services

Testing Details

Panel Name: Nail Testing

Panel Description: Nail Testing Drug Panel

Type: Profile

Matrix: Nail

Collection Container: Foil in Secure Envelope

Sample Amount: 100 mg = 10 clippings @ 2mm thick   (Larger profiles may require more. We recommend weighing the specimen on a jeweler's scale.)

Storage Conditions: Room Temperature

Transport Conditions: Ambient

Method: Initial screening test with confirmation of presumptive positives

Turn-Around Time: 1 day for negatives / 2-3 days for positives

  • References
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Can a nail test be used to prove that a previously taken hair test was inaccurate?

No, the result of any second collected specimen has absolutely no bearing on the validity of the result of any first collected specimen because you have no idea what the donor did between time A and time B.

Can someone test positive in fingernail because of passive or environmental exposure?

Yes, environmental exposure versus ingestion must be resolved when interpreting drug tests using fingernails.

How do drugs get into nails?

Drugs are distributed via the blood supply to the nail cells and the nail bed. Nails grow not only in length but in thickness as well. As the nail grows in thickness, it creates layers of drug history.

How much fingernail needs to be collected?

The optimum amount of nail clippings needed is 100 milligrams. If trimming all 10 fingernails, each clipping must be at least 2 millimeters to 3 millimeters long.

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.

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.

Why was one matrix positive and another negative on the same donor?

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.

Will one-time drug use be detected in Fingernail Testing? How many times would they have to use drugs for it to be detected in nails?

Single doses do not guarantee a positive result. The number of doses required to generate a positive result is highly variable between donors.




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