Quality analysis of raw materials used in cosmetics MCQs With Answer

Introduction:

This quiz set focuses on the quality analysis of raw materials used in cosmetics, tailored for M.Pharm students studying Herbal and Cosmetic Analysis (MPA 204T). It covers analytical approaches, physicochemical tests, identification methods, and regulatory standards applied to oils, waxes, extracts, preservatives, colorants and other cosmetic raw materials. Questions emphasize practical laboratory tests such as peroxide, acid and saponification values for lipids, microbial limits, heavy metal and pesticide screening, chromatographic and spectroscopic identification, and stability-related assessments. These MCQs are designed to reinforce understanding of test selection, interpretation of results and compliance with pharmacopeial and ISO standards relevant to cosmetic raw material quality control.

Q1. Which physicochemical test is most appropriate to assess the extent of oxidation in vegetable oils used as cosmetic raw materials?

• Acid value
• Saponification value
• Peroxide value
• Iodine value

Correct Answer: Peroxide value

Q2. Which analytical technique is best suited for the qualitative identification of functional groups in a herbal extract used in cosmetics?

• Gas chromatography (GC)
• Fourier transform infrared spectroscopy (FTIR)
• High performance liquid chromatography (HPLC)
• Atomic absorption spectroscopy (AAS)

Correct Answer: Fourier transform infrared spectroscopy (FTIR)

Q3. For assessing the purity and quantifying volatile fragrance components in a raw perfume concentrate, which method is most appropriate?

• HPLC with UV detection
• Gas chromatography with flame ionization detection (GC-FID)
• UV-visible spectrophotometry
• Gravimetric analysis

Correct Answer: Gas chromatography with flame ionization detection (GC-FID)

Q4. Which test is commonly used to evaluate the average molecular weight range and degree of unsaturation of fats and waxes in cosmetic raw materials?

• Saponification value and iodine value
• Peroxide and acid values
• Refractive index and optical rotation
• Moisture content and total ash

Correct Answer: Saponification value and iodine value

Q5. Which microbiological specification is critical for water-soluble cosmetic raw materials and typically evaluated during QC?

• Total viable aerobic count (TVAC) and absence of specified pathogens
• Peroxide value and rancidity index
• pH and refractive index
• Viscosity and particle size

Correct Answer: Total viable aerobic count (TVAC) and absence of specified pathogens

Q6. In heavy metal screening of herbal raw materials for cosmetics, which metal is most often monitored because of regulatory limits and toxicity concerns?

• Magnesium
• Lead
• Potassium
• Calcium

Correct Answer: Lead

Q7. Which parameter is most informative about the free fatty acid content (hydrolytic rancidity) in a fixed oil used in cosmetics?

• Iodine value
• Peroxide value
• Acid value
• Saponification value

Correct Answer: Acid value

Q8. When analyzing a colored botanical extract for potential synthetic dye adulteration, which method provides both separation and sensitive detection of impurities?

• Thin layer chromatography (TLC)
• UV-visible spectrophotometry
• HPLC with diode-array detection (HPLC-DAD)
• Loss on drying

Correct Answer: HPLC with diode-array detection (HPLC-DAD)

Q9. Which test helps determine the degree of unsaturation (double bonds) in fatty materials and affects drying properties of cosmetic oils?

• Peroxide value
• Saponification value
• Iodine value
• Acid value

Correct Answer: Iodine value

Q10. For raw materials intended as preservatives in cosmetics, which assay is essential to confirm potency and label claim?

• Antimicrobial preservative efficacy (challenge) test
• Moisture content determination
• Specific gravity measurement
• pH determination

Correct Answer: Antimicrobial preservative efficacy (challenge) test

Q11. Which parameter is typically used to detect hydroperoxides and early stages of lipid oxidation in oils and is critical for shelf-life prediction?

• Peroxide value
• Saponification value
• Specific gravity
• Optical rotation

Correct Answer: Peroxide value

Q12. During quality control of powdered herbal raw materials for cosmetics, what does ‘loss on drying’ primarily measure?

• Total ash content
• Volatile matter including moisture
• Extractable fats and oils
• Heavy metal contamination

Correct Answer: Volatile matter including moisture

Q13. Which guideline or standard is commonly referred to for acceptable microbial limits and testing methods for cosmetic raw materials?

• USP for injectables
• ISO 21149 and ISO 22716 (Good Manufacturing Practices)
• ICH Q3 for impurities in pharmaceuticals
• AOAC methods for food only

Correct Answer: ISO 21149 and ISO 22716 (Good Manufacturing Practices)

Q14. Which chromatographic technique is preferred to quantify pesticide residues in botanical raw materials used in cosmetics?

• Thin layer chromatography (TLC)
• HPLC with refractive index detection
• GC-MS or LC-MS/MS
• Paper chromatography

Correct Answer: GC-MS or LC-MS/MS

Q15. Which test is commonly used to assess the oxidative stability of antioxidants added to cosmetic oils?

• Microbial limit test
• Rancimat or accelerated oxidation (induction time) test
• pH stability test
• Viscosity-shear analysis

Correct Answer: Rancimat or accelerated oxidation (induction time) test

Q16. For glycerides and surfactants used in cosmetic formulations, which measurement helps determine purity and degree of esterification?

• Saponification value
• Moisture content
• Coliform count
• Optical rotation

Correct Answer: Saponification value

Q17. When verifying botanical identity of an herbal raw material used in cosmetics, which combination of tests provides the most reliable confirmation?

• Organoleptic evaluation and moisture content only
• Macroscopic/microscopic morphology plus chemoprofile by TLC/HPLC
• Only ash value measurement
• Only FTIR fingerprinting

Correct Answer: Macroscopic/microscopic morphology plus chemoprofile by TLC/HPLC

Q18. Which measurement indicates the presence of unsaponifiable matter in an oil or wax used as a cosmetic raw material?

• Determination of refractive index
• Unsaponifiable matter assay after saponification and extraction
• Peroxide value
• pH of the oil

Correct Answer: Unsaponifiable matter assay after saponification and extraction

Q19. For raw colorants used in cosmetics, which specific test ensures absence of carcinogenic contaminants such as heavy polycyclic aromatic hydrocarbons (PAHs)?

• Moisture by loss on drying
• GC-MS screening for PAHs
• Gravimetric ash determination
• Peroxide value

Correct Answer: GC-MS screening for PAHs

Q20. Which parameter is crucial for characterizing the emollient properties and spreadability of an oil used as a cosmetic raw material?

• Viscosity and dynamic rheological profile
• Total ash content
• Heavy metal content
• Moisture by Karl Fischer only

Correct Answer: Viscosity and dynamic rheological profile

Download