Pharmaceutical Raw Materials: 7 Critical Handling Errors That Compromise Drug Quality

Photo: Toon Lambrechts / Unsplash

Pharmaceutical raw materials, whether active pharmaceutical ingredients (APIs) or excipients, require a precise approach to handling and storage. Even minor deviations from proper procedures can cause degradation, microbial contamination, or loss of key properties. Drug manufacturers often face recurring errors—from inadequate humidity control to incorrect labeling of packaging. These issues not only jeopardize the quality of the final product but can also lead to regulatory complications or financial losses. What risks should be avoided, and what principles should be followed?

1. Failure to maintain temperature control: How temperature affects raw material stability

Temperature is one of the most critical factors affecting the stability of pharmaceutical raw materials. Many active substances, excipients, or solvents are sensitive to temperature fluctuations, which can accelerate degradation, alter chemical structure, or reduce efficacy. For example, some protein substances or biological materials require storage at temperatures below -20 °C, while other raw materials, such as certain oils or waxes, may crystallize or lose homogeneity at low temperatures. Exceeding the recommended temperature range by even a few degrees can lead to irreversible changes.

To minimize risks, it is essential to follow the manufacturer’s specifications and use calibrated cooling or freezing equipment with continuous temperature monitoring. It is also recommended to implement an alert system for exceeding limits and regularly check the functionality of the equipment. In the event of a power supply interruption or cooling failure, immediate corrective actions must be taken, such as transferring raw materials to backup storage or documenting the incident for subsequent quality assessment.

2. Contamination During Handling: How to Prevent Cross-Contamination

Cross-contamination poses a serious risk to the quality of pharmaceutical raw materials, especially when handling spaces or equipment are shared for different substances. Even a small amount of foreign matter can cause a chemical reaction, degradation, or loss of efficacy, which can have a fatal impact on the final medicinal product. Typical sources of contamination include improperly cleaned tools, work surfaces, ventilation systems, or even the clothing and gloves of workers.

Prevention involves strict adherence to Good Manufacturing Practice (GMP) principles. This includes physical separation of handling areas for different categories of raw materials, the use of disposable or easily decontaminable tools, and regular cleaning and validation of equipment. Staff training in hygiene and procedures for handling sensitive substances is also crucial. For high-risk raw materials such as hormones or cytostatics, the use of dedicated spaces and equipment with a strict access regime is recommended.

Photo: Toon Lambrechts / Unsplash

3. Improper storage: Moisture, light, and air as silent enemies

Pharmaceutical raw materials are often sensitive to moisture, light, and oxygen, which can accelerate their degradation. Moisture can cause hydrolysis or promote microbial growth, light (especially UV radiation) can induce photochemical reactions, and oxygen leads to oxidation. For example, some vitamins, antibiotics, or lipids are extremely sensitive to these factors and require storage in an inert atmosphere, in opaque packaging, or with the use of desiccants.

To protect raw materials, it is crucial to use suitable packaging materials, such as multilayer films with barrier properties or containers made of dark glass. Storage areas should be equipped with humidity and temperature control, ideally with values maintained within a narrow range. It is also important to regularly check the integrity of packaging and monitor the expiration dates of raw materials, which can be affected by storage conditions. For sensitive substances, the use of stabilizers such as antioxidants or chelating agents is recommended.

4. Incorrect Documentation: Why Accurate Records Are Key to Quality and Compliance

Documentation is a fundamental pillar of quality assurance and compliance with regulatory requirements in the field of pharmaceutical raw materials. Incorrect or incomplete records can lead to mix-ups of raw materials, improper use, or issues during audits. Typical errors include incorrect batch labeling, missing records of temperature fluctuations, insufficient documentation of raw material receipt and release, or the absence of records on equipment cleaning and maintenance.

To minimize risks, it is essential to implement a robust documentation management system that includes clear labeling of all raw materials, including name, batch number, expiration date, and storage conditions. It is recommended to use electronic systems with automatic data recording to minimize human errors. It is also important to regularly train staff in proper documentation practices and conduct internal audits to verify compliance with both internal and external regulations, such as REACH or Good Manufacturing Practice (GMP) requirements.

Photo: TECNIC Bioprocess Solutions / Unsplash

5. Ignoring Packaging Material Compatibility: When Packaging Does More Harm Than Good

Choosing the wrong packaging material can significantly compromise the quality of pharmaceutical raw materials, even when all other storage conditions are met. Some substances react with plastics, glass, or metal components of packaging, leading to degradation, loss of efficacy, or even the formation of toxic compounds. For example, strong acids or bases can corrode metal closures, while certain organic solvents penetrate plastic packaging, causing swelling or the release of additives into the raw material.

Before using packaging, it is essential to verify its chemical compatibility with the specific raw material according to technical data sheets and manufacturer recommendations. For sensitive substances, packaging with an inert inner coating, such as fluoropolymers, or special glass containers with certified resistance are often used. It is also important to monitor changes in the appearance of the packaging—cloudiness, deformation, or color changes may indicate an ongoing reaction. In case of doubt, it is advisable to conduct stability tests according to standard pharmaceutical procedures.

6. Insufficient Validation of Cleaning Procedures: A Hidden Source of Contamination Between Batches

Cleaning processes between production batches are a critical point often underestimated even by experienced manufacturers. Residues of the previous raw material on equipment, containers, or tools can cause cross-contamination, which may not be immediately visible but significantly affects the quality of the drug. A typical example is allergenic substances, such as beta-lactams, which, even in trace amounts, can trigger severe reactions in sensitive patients.

Validation of cleaning procedures must include not only visual inspection but also analytical methods such as HPLC or mass spectrometry, capable of detecting residues in the microgram range. For each raw material, a maximum residual limit (MRL) should be established, and the cleaning procedure must be designed to reliably achieve this limit. It is also important to regularly review the effectiveness of cleaning processes, especially when raw materials or equipment are changed. Validation documentation must be part of the quality management system and available for audit purposes.

7. Underestimating Staff Training: The Human Factor as the Greatest Risk to Quality

Even the best-designed processes fail if staff are not adequately trained in handling pharmaceutical raw materials. A common mistake is the assumption that experienced workers do not need regular training or that training should be limited to the theoretical part only. In reality, it is precisely practical skills—proper use of protective equipment, sampling techniques, or handling sensitive substances—that determine quality and safety.

Training should be regular, documented, and focused on the specific risks associated with handling the given raw materials. For example, for moisture-sensitive substances, it is crucial to practice quick and proper sealing of containers, while for toxic or irritating raw materials, it is essential to rehearse procedures in case of spills or contamination. It is also important to include training on GMP (Good Manufacturing Practice) principles and REACH and CLP requirements so that staff understand the legislative demands and the consequences of non-compliance. Investing in quality training always pays off—preventing errors is cheaper than addressing their consequences.

Quality of Raw Materials is the Foundation of Safe Medicines

Every pharmaceutical raw material requires an individual approach to handling and storage. GCG Group provides detailed Safety Data Sheets (SDS) and technical documentation with recommendations for optimal conditions for each supplied raw material. If you have specific requirements or need advice on selecting suitable excipients or APIs, contact our experts. Get in touch – or browse our catalogue of over 1,300 products.