Table 3.
Household Chemicals Used as In Vitro Adulterants: Mechanism of Action, Tests Potentially Affected by Use, and Methods of Detection
| Chemical | Mechanism of Adulteration | Tests Done by Laboratories That Are Affected | Potential False-Negative Results | Method of Detection |
| Bleach (sodium hypochlorite) | Interferes in immunoassays; most effective urine adulterant | EMIT II24 | THC | AdultaCheck 423,24 |
| CEDIA20 | Amphetamine, opioids, cocaine, PCP, benzodiazepines, barbiturates | Intect 724 | ||
| EIA29 | Opioids, cocaine, barbiturates, benzodiazepines | |||
| FPIA30 | THC | |||
| RIA31,32 | THC | |||
| GC/MS32 | THC | |||
| Vinegar (acetic acid) | Lower pH levels, which can affect binding, reaction times, and drug solubility | FPIA31 | THC | AdultaCheck 424 |
| EIA32 | THC | Intect 724 | ||
| EMIT II24 | THC | Mask Ultra Screen24 | ||
| Monitect PC1122 | Amphetamine | |||
| Visine eye drops | Uptake of THC through benzalkonium chloride (inactive ingredient in Visine eye drops) reduces the binding in immunoassay drug screens | EMIT33 | THC | … |
| CEDIA20 | THC | |||
| FPIA31 | THC | |||
| EIA32 | THC | |||
| RIA31 | THC | |||
| Drano (sodium hydroxide, also known as caustic soda) | Oxidation reaction; it also changes the pH of the urine to alkaline, which can affect binding, reaction times, and drug solubility | CEDIA20 | THC, amphetamine, opioids, cocaine, PCP, benzodiazepines, barbiturates | Intect 722 |
| EIA32 | THC, amphetamine, opioids, cocaine, benzodiazepines, barbiturates | |||
| FPIA31 | Opioids, PCP | |||
| Monitect PC1122 | THC | |||
| Detergent/soap | Alters pH of urine and also interferes with drug binding on immunoassays | CEDIA20 | THC, amphetamine, opioids, cocaine, PCP, barbiturates | … |
| EIA32 | THC, benzodiazepines, barbiturates | |||
| FPIA31 | THC, cocaine | |||
| EMIT34 | THC | |||
| RIA31 | Cocaine | |||
| Ammonia | … | EMIT II24 | Cocaine, PCP | Intect 724 |
| AdultaCheck 424 | ||||
| Table salt (sodium chloride) | May affect immunoassay results by changing protein structures, which then alter enzyme activity and drug binding | EMIT35 | Amphetamine, opioids, cocaine, barbiturates, PCP, benzodiazepines | Specific Gravity36,37 |
| FPIA31 | THC |
Abbreviations: CEDIA = cloned enzyme donor immunoassay, EIA = enzyme immunoassay, EMIT = enzyme multiplied immunoassay, FPIA = fluorescence polarization immunoassay, GC/MS = gas chromatography/mass spectrometry, PCP = phencyclidine, RIA = radioimmunoassay, THC = tetrahydrocannabinol.
Symbol: … = not applicable.