Residual Solvent Testing for Herbal Extracts and AYUSH Products
Most AYUSH and herbal extracts involve a solvent extraction step — ethanol or hydro-ethanolic for alcoholic extracts, hexane for fixed-oil extraction, and methanol or dichloromethane in some legacy and specialised processes. Residual solvent left in the finished extract must be controlled per ICH Q3C and the pharmacopoeial herbal monograph. Without documented residual solvent data, AYUSH licence dossiers are incomplete, EU and US export submissions are rejected, and Gulf SFDA import dossiers stall. Auriga Research provides NABL-accredited residual solvent testing using USP 467 headspace GC-FID with GC-MS confirmation, scoped to the ICH Q3C Class 1, Class 2, and Class 3 solvent framework.
Our panel covers Class 1 avoidance markers (benzene at 2 ppm, carbon tetrachloride at 4 ppm, 1,2-dichloroethane at 5 ppm, and other Class 1 contaminants), Class 2 solvents reported against the Permitted Daily Exposure (methanol PDE 30 mg/day, dichloromethane PDE 6 mg/day, hexane PDE 2.9 mg/day, toluene, chloroform), and Class 3 solvents at the GMP control limit (ethanol, acetone, ethyl acetate, isopropanol). Reports cite the ICH Q3C class, the USP 467 method reference, and the per-preparation API, IP, EP, or USP herbal monograph where one applies.
Testing is performed at our Delhi HQ (Arbro Analytical Division, NABL TC-7375) — India's first herbal testing lab licensed by the Directorate of ISM&H, AYUSH approved since 2004 (DTL-01 A&U), and holder of the Unani licence. Backed by the Arbro Group's unbroken NABL ISO/IEC 17025:2017 accreditation since 2003, reports are accepted by the Ministry of AYUSH, CDSCO, state AYUSH licensing authorities, and EU / US / Gulf / ASEAN export regulators including those aligned with the WHO Quality Control Methods for Medicinal Plant Materials.
Residual Solvent Testing Capabilities
Each capability is mapped to the ICH Q3C class, the analytical method, and the regulatory anchor so AYUSH QA, regulatory consultants, and export-dossier teams can scope at a glance.
ICH Q3C Class 1 — Avoidance Markers
Benzene (2 ppm), carbon tetrachloride (4 ppm), 1,2-dichloroethane (5 ppm), 1,1-dichloroethene, and 1,1,1-trichloroethane. Should be avoided in manufacture; tested as contamination markers in starting solvents and the finished extract.
ICH Q3C Class 2 — PDE-Limited
Methanol (PDE 30 mg/day, ~3000 ppm), dichloromethane (PDE 6 mg/day, 600 ppm), hexane (PDE 2.9 mg/day, 290 ppm), toluene, chloroform, and other Class 2 solvents reported against the Permitted Daily Exposure limit.
ICH Q3C Class 3 — GMP-Controlled
Ethanol, acetone, ethyl acetate, isopropanol, and other Class 3 solvents. Low toxicity, GMP-controlled at a typical 50 mg/day limit. Ethanol is the most common AYUSH extraction solvent.
USP 467 Headspace GC-FID
Pharmacopoeial reference method — headspace gas chromatography with flame ionisation detection per USP 467. Default routine method for the ICH Q3C panel.
GC-MS Confirmation
GC-MS confirmation runs in parallel for unknown peak identification, low-level trace confirmation, and dossier requirements that specify mass-spectrometric confirmation alongside HS-GC-FID.
EU / US / Gulf / WHO Compliance
Reports cite ICH Q3C class limits, the pharmacopoeial herbal monograph (API / IP / EP / USP), and destination-market requirements (EU EMA, US FDA, Gulf SFDA, WHO Quality Control Methods for Medicinal Plant Materials).
ICH Q3C class framework: Class 1 solvents should be avoided in manufacture; tested as contamination markers. Class 2 solvents are limited by Permitted Daily Exposure (PDE) — methanol 30 mg/day, hexane 2.9 mg/day, dichloromethane 6 mg/day. Class 3 solvents (ethanol, acetone, ethyl acetate) are low toxicity, GMP-controlled at a typical 50 mg/day limit. The per-preparation API, IP, EP, or USP herbal monograph may apply stricter limits than the ICH Q3C generic class limit.
How It Works
Get a Quote
Share your extract (alcoholic / hydro-alcoholic / hexane / methanol / other), the extraction solvent used in manufacture, the AYUSH framework (API / UPI / SPI / Homeopathy), and the target market. Your dedicated SPOC confirms the residual solvent panel (full ICH Q3C or targeted), the relevant pharmacopoeial monograph reference, and the sample quantity required before you dispatch.
Send Your Sample
Dispatch the herbal extract or finished AYUSH product with a completed Test Request Form to the Delhi HQ (Arbro Analytical Division) lab. Each sample is bar coded and registered in YLIMS, Auriga's in-house Laboratory Information Management System, upon receipt. Testing begins within 24 hours of registration.
HS-GC-FID Testing and QA Review
Your sample is analysed by headspace gas chromatography with flame ionisation detection (HS-GC-FID) per USP 467 for the agreed ICH Q3C solvent panel. GC-MS confirmation runs in parallel where the dossier requires mass-spectrometric confirmation. Every result is interpreted against the ICH Q3C class limit and the per-preparation API / IP / EP / USP herbal monograph, then passes formal internal QA review and sign-off before the report is generated.
Receive Your NABL Report
Your NABL-accredited residual solvent report is delivered digitally within the committed turnaround time. Reports cite each solvent detected, the ICH Q3C class, the applicable limit (PDE or GMP control), and the compliance verdict against the target-market regulatory framework. Accepted by Ministry of AYUSH, CDSCO, state AYUSH licensing authorities, and EU / US / Gulf / ASEAN export regulators. Track sample status through YLIMS.
Turnaround Time
| Panel | Standard TAT | Express |
|---|---|---|
| Full ICH Q3C panel by HS-GC-FID (Class 1 + 2 + 3) | 5 to 7 business days | Available |
| Class 2 PDE-limited solvents only | 5 to 7 business days | Available |
| Targeted single-solvent (e.g. methanol, hexane only) | 3 to 5 business days | Available |
| GC-MS confirmation (parallel run) | 7 to 10 business days | Available |
| Per-preparation API / IP / EP herbal monograph compliance | 7 to 10 business days | On request |
| Export-compliance package (EU / US / Gulf / WHO) | 7 to 10 business days | On request |
Who Needs Residual Solvent Testing
- AYUSH-licensed manufacturers of alcoholic, hydro-alcoholic, and hexane-extracted herbal preparations preparing Ministry of AYUSH licence dossiers.
- Herbal extract manufacturers selling to AYUSH product formulators who require ICH Q3C documentation at the raw material handover.
- Exporters of herbal extracts and AYUSH products to EU (EMA), US (FDA), and Gulf (SFDA) markets where residual solvent data is part of the import dossier.
- Brands reformulating to replace Class 2 solvents (methanol, dichloromethane, hexane) with Class 3 alternatives (ethanol, acetone, ethyl acetate) and needing fresh data on the new solvent profile.
- Pharma-bridging herbal products (rasayanas, classical formulations being filed under quasi-drug routes) requiring full ICH Q3C compliance.
- CDMO clients producing herbal extracts under contract, building safety and regulatory dossiers for brand-owner handover.
- AYUSH GMP auditees facing inspection where residual solvent control is a Schedule T check point.
- Brands contesting an EU customs detention, US FDA import alert, or Gulf SFDA finding on residual solvents — full re-test on NABL chain of custody.
Why Auriga for Residual Solvent Testing
Full ICH Q3C Panel in One Run
Class 1 avoidance markers, Class 2 PDE-limited solvents, and Class 3 GMP-controlled solvents all reported from a single HS-GC-FID analytical run per USP 467.
HS-GC-FID + GC-MS Confirmation
Headspace GC-FID for routine quantification with GC-MS confirmation running in parallel for unknown peak identification and dossiers that specify mass-spectrometric confirmation.
Per-Preparation Monograph Applied
Reports cite both the ICH Q3C class limit and the per-preparation API / IP / EP / USP herbal monograph limit where one applies. The stricter limit governs the verdict — surfaced explicitly.
First ISM&H-Licensed Herbal Lab
Delhi HQ is India's first herbal testing lab licensed by the Directorate of ISM&H — AYUSH approved since 2004, holder of the Unani licence. The audit trail Ministry of AYUSH and export regulators look for in a herbal residual solvent partner.
Reformulation Bridge Data
Routine residual solvent panels for brands switching from Class 2 (methanol, hexane, DCM) to Class 3 (ethanol, ethyl acetate) solvents — generating before-and-after bridge data for the dossier.
NABL Reports for EU / US / Gulf
NABL ISO/IEC 17025:2017 reports accepted by EMA, US FDA, Gulf SFDA, ASEAN authorities, and WHO-aligned reviewers. Arbro Group analytical heritage since 2003 — Arbro Lab since 1990, Auriga Research since 2007.