SUMMARY: If your team is under pressure to reformulate, here’s the quickest way to reduce risk in the process: make ICH Q1B-aligned photostability testing your top priority. It’s the most direct method for detecting potential color shift, fading, or degradation problems before you scale up to full production. Following ICH Q1B requirements will also ensure the integrity and traceability of your data, which is critical for when results need to stand up to internal QA review, audits, or regulatory scrutiny.
Why Manufacturers Are Rethinking Color Additives
Regulatory scrutiny on color additives is tightening globally as seen in the FDA’s ongoing review of synthetic petroleum-based colorants for food and cosmetics. This has many manufacturers reassessing their formulations and testing natural or alternative pigments to keep pace with evolving market and regulatory expectations.
This shift renews the central questions of stability, shelf life, and compliance, while introducing new uncertainty around how natural colorants respond to light exposure.
What Changes When You Move to Natural Colorants
Natural pigments are usually more light-sensitive than the synthetics we’ve relied on. You will often see these colorants experience delta E drift, chromophore breakdown, or change hue differently depending on what they’re mixed into; especially when exposed to UV and visible light.
To ensure reliable results, separate your UV and VIS light tests and maintain tight temperature and humidity control. This lets you quickly identify the cause and establish reliable benchmarks.
Basic Requirements for a Valid Photostability Study (Aligned with ICH Q1B)
If you’re looking to run studies that save you time and money later, here’s our four-point checklist:
- Define the light challenge explicitly (UV vs visible, or both) and ensure it matches the product’s intended lifecycle.
- Control climate tightly. Keep the temperature and humidity consistent. That way, you know the color change is being caused by the light and not the climate.
- Use accelerated conditions. This is great for quickly ranking candidate colorants, but you must always confirm the top performers under the actual long-term conditions listed on the product label. Caution: accelerated studies should confirm that the degradation mechanism remains consistent with real-time testing.
- Keep 21 CFR Part 11 compliant data records. This is non-negotiable. The same data needs to serve R&D, QA, and external audits without rework.
Equipment Requirements for Regulatory Compliance
To make your work reproducible, reliable, and audit-ready, look for these critical features when sourcing stability chambers:
- Validated to meet ICH Q1B light-exposure requirements (i.e. proven UV and visible light intensity and duration within ICH-defined limits)
- Independent control of UV and visible light parameters.
- Uniform temperature distribution paired with precise climate control.
- Support for accelerated testing (essential for candidate triage).
- Versatility to handle different product types, including food, pharma, and cosmetics.
- 21 CFR Part 11-compliant data recording baked in.
These features form the foundation of a reliable system. If you want your screening data to back up shelf-life claims and regulatory filings, your system needs to deliver on each of these points.
Real-World Applications Across Industries
- Food & Beverage: Here, the challenge is keeping color stable in complex recipes like high-water drinks, fat emulsions, and low-pH (acidic) beverages. Since these products often sit on retail shelves, light exposure is a major and highly variable risk.
- Cosmetics: While color additives are batch-certified, photostability evidence is what truly supports appearance claims over the product’s lifespan.
- Non-Active Pharma/Medical Components: This involves colorants used in inactive ingredients. Even though the color isn’t the active drug, a consistent appearance is still important for brand identity and patient acceptance and therefore needs to hold up over time.
Four Core Principles for Efficient Photostability Work
The most efficient teams break their photostability work into these four key phases to quickly generate the necessary data for regulatory approval:
- Screen: Run candidate colorants under separate UV and VIS lighting with tight temperature and relative humidity control. This quickly exposes the obvious non-starters.
- Rank: Move the top performers to accelerated testing to prioritize the top 1–2 candidates for full-scale formulation work.
- Confirm: Test those top candidates under label-claim conditions and capture all raw data and metadata in a 21 CFR Part 11 system.
- Lock: Finalize specifications and shelf-life assumptions with an ICH Q1B-aligned summary that your QA team can easily sign off on.
Equipment That Supports Your Transition to Natural Colorants
If you’re beginning reformulation work with natural colorants and need ICH Q1B photostability testing capabilities, it’s worth considering the capabilities of your equipment. BMT USA stability chambers are designed specifically to meet the requirements outlined in this article: full ICH Q1B light spectrum control, precise temperature and humidity regulation, integrated UV and visible light testing, and 21 CFR Part 11-compliant data systems.
Whether you’re working in food, cosmetics, or pharmaceuticals, BMT USA stability chambers deliver a solution that meets your specific demands while maintaining consistent conditions across all your testing, ensuring your early-stage data can directly support your final shelf-life claims.
Learn more
Explore BMT USA photostability chamber capabilities and options: bmtusa.com/stability-chambers.