If you ask a regular person, do you know about impurity?

His/ Her answer would be that it is the state to eliminate all the unnecessary in any particular solution.

But what if we ask from a person who is into Pharma, His answer would be different

What are impurities?

Impurities are unwanted substances that are present in a material or product. These substances can originate from a variety of sources, such as from the raw materials used in production, from the manufacturing process itself, or from the environment. Impurities can have a wide range of effects on the final product, from having no impact to rendering the product unsafe for consumption. In this article, we will explore the different types of impurities, their sources, and their effects on the final product, as well as the methods used to detect and remove impurities.

When it comes to the pharmaceutical industry impurities can have a significant impact on the safety and efficacy of drugs. Impurities can be introduced at various stages of the drug development and manufacturing process, such as during synthesis, isolation, purification, and formulation. Also, Impurities can include residual solvents, catalysts, and by-products from the synthesis process, as well as contaminants from the manufacturing environment. These impurities can affect the stability, purity, and potency of the drug. In some cases, impurities can also be toxic or have harmful side effects.

Is it possible to classify Impurities?

One way to classify impurities is by their origin. Impurities can be naturally occurring, such as minerals found in raw materials, or they can be artificially introduced, such as through the manufacturing process. Naturally occurring impurities can have a range of effects on the final product, from having no impact to rendering the product unsafe for consumption. Artificially introduced impurities can come from a variety of sources, such as from the raw materials used in production, from the manufacturing process itself, or from the environment.

Another way to classify impurities is by their chemical composition. Impurities can be inorganic or organic, with inorganic impurities being composed of elements such as sulfur, chlorine, or heavy metals, while organic impurities are composed of compounds such as pesticides, solvents, or bacteria. Inorganic impurities can have a range of effects on the final product, from having no impact to rendering the product unsafe for consumption, while organic impurities can also have a wide range of effects, from having no impact to rendering the product unsafe for consumption.

Impurities can also be classified based on their solubility in a particular solvent. Water-soluble impurities can be removed by washing with water, while oil-soluble impurities can be removed by washing with an organic solvent. Solubility is a crucial factor in determining the methods used to remove impurities.

Impurities that are classified based on their effect on the final product. Harmful impurities can have a range of effects, from causing the product to be unsafe for consumption to rendering the product ineffective. Harmless impurities have no impact on the final product. The presence of harmful impurities can be dangerous and it's very important to detect them as early as possible.

Impurities can also be classified by their level of purity. Trace impurities are present in very small amounts and have little or no effect on the final product, while residual impurities are present in larger amounts and can have a significant impact on the final product.

Why does ICH Q3D links with Impurities

 The connection ICH Q3D is a guideline developed by the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) that provides guidance on the control of elemental impurities in drug products. The guideline addresses the risk of exposure to elemental impurities, such as heavy metals, that may be present in drug products and can have toxic effects on patients.

The guideline establishes acceptable daily exposure (ADE) limits for 24 elemental impurities, including heavy metals such as lead, mercury, and arsenic, and provides recommendations for their control through the use of raw materials and manufacturing processes that minimize their presence in the final product.

Effects of Impurities in pharmaceuticals

Impurities in pharmaceuticals can have a significant impact on the safety and efficacy of the final product. Impurities can be defined as any substance that is not the active pharmaceutical ingredient (API) in a drug product. These impurities can be present in the raw materials used to produce the drug, or they can be formed during the manufacturing process.

One major concern with impurities in pharmaceuticals is their potential to cause harm to patients. Some impurities can be toxic or carcinogenic, and long-term exposure to these substances can lead to serious health problems. Additionally, some impurities can interact with the API in unexpected ways, which can alter the safety and efficacy of the drug. For example, some impurities may decrease the effectiveness of the drug or increase the likelihood of side effects. Also, another concern with impurities in pharmaceuticals is that they can negatively impact the stability of the final product. Impurities can interact with the API and other excipients in the drug, leading to changes in physical or chemical properties. This can result in changes in the appearance, smell, or taste of the drug, or it can cause the drug to degrade more quickly. This can lead to reduced efficacy of the drug and make it less safe for patients to use.

The detection and removal of impurities are crucial to ensure the safety and quality of the final product. A variety of methods can be used to detect and remove impurities, including physical methods such as filtration and centrifugation, chemical methods such as precipitation and distillation, and biological methods such as fermentation and cultivation.

Conclusion

In summary, impurities are unwanted substances that can originate from a variety of sources and have a wide range of effects on the final product. They can be classified by their origin, chemical composition, solubility, effect on the final product, and level of purity. The detection and removal of impurities are crucial to ensure the safety and quality of the final product and a variety of methods can be used to do so. It is important for manufacturers to be aware of the potential sources of impurities and to have a plan in place to detect and remove them to ensure the safety and quality of their products.                

Do you want to understand more about Impurities? Join our upcoming Impurities EU edition Masterclass.

By Nafhan Naseem, Jr. Social Media Executive & IT Support, GLC Europe, Colombo Office, Sri Lanka.