Monday, September 13, 2021

Specimen validity testing the test before the (drug) test

Specimen validity testing the test before the (drug) test

Specimen validity testing (SVT) is performed on a urine drug screen specimen to detect substitution, adulteration, or dilution.

Specimen validity testing (SVT) is a critical component of urine drug screening programs. The process of collecting and testing urine samples for drugs of abuse can be susceptible to adulteration or substitution, making it challenging to ensure accurate test results. 

Specimen validity testing (SVT) is using substitution techniques,diluting urine, or adding a substance to a sample.

CharacteristicsNormal Range
Creatinine, mg/dL20–400
Specific gravity1.002–1.030
pH4.5–8.0
Temperature, within 4 minutes of voiding, °F90–100


 SVT is a multifaceted process that includes various methods and techniques.

 Dilution When someone drinks a significant amount of water shortly before providing a urine sample for donation or due to certain physiological conditions, it can lead to diluted urine. This dilution can cause drug or metabolite concentrations to fall below the initial test cutoff, potentially resulting in a false negative outcome. Dilution will mainly effect creatinine and specific gravity. 

 

Creatinine: Creatinine is a natural substance found in urine. It is created when muscle tissue breaks down and is eliminated from the body through the kidneys. Typically, the concentration of creatinine in urine falls within the range of 20 to 400 mg/dL. However, levels outside of this range can indicate factors such as excessive fluid intake, renal failure, diet, or various other medical conditions.

Specific Gravity: Specific gravity (SG) is a measure of the density of a liquid compared to the density of water. It helps determine the concentration of dissolved particles in a urine sample. A decrease in SG values may be attributed to factors like excessive fluid intake,

 

 

 Adulteration —Adding a substance to a specimen after it has been collected. The product added is designed to mask the presence of, or chemically destroy, the drug or drug metabolite that the specimen may contain. An adulterant product may be added with the intention of adversely affecting the testing reagents.

Adulterated Specimen

Urine samples with a pH level below 4.0 or above 9.0 are considered adulterated. An adulterated specimen refers to a urine sample that contains a substance not typically found in urine or an endogenous substance present at an abnormal concentration compared to normal physiological levels. 

Adulterants are products added to the urine with the purpose of masking or chemically destroying the presence of drugs or drug metabolites that the specimen may contain. Adulterant products can also be added to interfere with the testing reagents, or in the case of liquid synthetic urine, act as a preservative to maintain its stability over time.

  Some common oxidants used to attempt to alter urine drug test results are bleach, biocides, nitrate, chromate, iodate, and peroxidase. A positive result for oxidant activity should be considered when interpreting drug results.

 The most popular liquid urine product contains biocides and peroxides and if use din a reputable lab will result in “not consistent with human urine”

pH


The pH level of a urine sample indicates its acidity or alkalinity. Typically, urine pH values range from 4.5 to 9.0. However, if urine specimens are stored under unfavorable conditions such as high temperatures, the pH may rise as high as 9.5. Abnormally high or low pH levels can suggest tampering or adulteration of the sample.

When assessing urine samples, creatinine, specific gravity (SG), and pH are taken into account to determine their validity. All three criteria must fall within the range of normal human urine for a sample to be considered valid. 

 

 These tests are used to assess the validity of the urine specimen by determining its composition and consistency. A urine sample that falls outside the expected ranges for any of these parameters may be indicative of tampering or adulteration.

Urine StatesDescription
DilutedUrine creatinine ≥ 2 mg/dL but < 20 mg/dL
Specific gravity > 1.001 but < 1.030

SubstitutedUrine creatinine < 2 mg/dL
Specific gravity < 1.001 or > 1.020

AdulteratedpH < 3 or > 11
Nitrite concentration > 500 mcg/mL
Chromium concentration > 50 mcg/mL
Presence of: Halogen (bleach, iodine, fluoride), glutaraldehyde, pyridine, surfactant

In addition to these methods, SVT also involves chain of custody procedures, including documentation and tracking of the sample from collection to testing. This ensures that the sample has not been tampered with or substituted during the collection process.

The use of SVT is essential for maintaining the integrity of urine drug screening programs. It provides a reliable mechanism for detecting attempts to alter or adulterate urine specimens and ensures accurate test results. SVT can help prevent false negatives or false positives, which can have significant consequences for individuals undergoing drug testing.

It is important to note that SVT is not foolproof and can be susceptible to manipulation by individuals attempting to cheat the system. However, the use of multiple SVT methods and stringent chain of custody procedures can help minimize the risk of tampering or substitution.

In conclusion, SVT is a critical component of urine drug screening programs. It involves various methods and techniques to assess the validity of urine specimens and detect attempts to tamper with or adulterate them. The use of SVT helps maintain the integrity of drug testing programs and ensures accurate test results.



 Watch a Sample Validly Test  on  Synthetic urine  

 showing proper validity levels of the FAKE IT synthetic urine 



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