Analytical methods
Learn how laboratories separate, identify, and quantify chemical compounds.
Independent scientific education
Forensic toxicology, explained with clarity.
Explore how laboratory testing, pharmacology, specimen quality, and measurement limits shape toxicology findings. The resource library uses direct, readable scientific language.
Held to be an expert in forensic toxicology by thousands of tribunals nationally & internationally.
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A practical reference
Method-aware science for better understanding.
Every resource begins with the test or scientific question at hand, then explains the procedures, quality practices, context, and limits that belong in a careful interpretation.
Specimens & matrices
Understand why sample type, collection, storage, and preparation matter.
Limits & context
See why results should be read with timing, method, and uncertainty in mind.
New technical guides
Recent source-cited analysis
What a Toxicology Result Can—and Cannot—Tell You
A practical framework for separating analytical detection from timing, dose, impairment, and causation.
Total THC by GC-MS: Matrix Bias and Analyte Protectants
How calibrant adsorption and cannabis matrix effects can change total-THC results, and which controls laboratories should validate.
THC and CBD Derivatization: A GC-MS Identification Trap
Why derivatization and ion-source chemistry can make THC and CBD analytically indistinguishable without additional evidence.
False-Positive Urine Drug Screens: Assay-Specific Evidence
Why cross-reactivity depends on the exact assay, cutoff, metabolites, and independent confirmatory method.
THC Hair Testing by DART-MS: Selectivity and Interference
How endogenous isobaric ions, resolving power, ion mobility, and the sensitivity-selectivity tradeoff affect direct THC hair analysis.
Blood THC Timeline After Smoking Cannabis
Why parent THC, active 11-OH-THC, and inactive THC-COOH follow different plasma timelines after controlled smoking.
About this library
Clear explanations without overstatement.
This website is an educational resource for people looking to understand forensic toxicology topics. It is not medical advice, and a laboratory result should always be evaluated in its specific scientific context.
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Explore the science.
Begin with the scientific resource library and follow the links between related topics. For litigation-focused evidence resources, visit the Forensic Toxicology Evidence Library. For legal representation and expert-witness services, visit OkorieOkorocha.com.