Biocides And Their Many Applications

What Are Biocides?

Biocides are non-antibiotic agents used as preservatives, disinfectants, or antiseptics. Although most biocides are chemical agents, microorganisms can also be used as biocides to suppress the growth of other organisms. Biocides act either by killing microorganisms or inhibiting their growth. Biocides can be further classified by their intended application. Preservatives are added to products to increase their shelf-life by preventing microbial decomposition. Disinfectants are agents that are applied to inanimate objects and surfaces, whereas antiseptics are agents applied to living tissue such as mucous membrane or skin. In today’s world, biocides are frequently encountered.  Preservatives are ubiquitous and are found in a diverse array of products ranging from food, beverages, and cosmetics to pharmaceutical drugs, biological samples, and research products. Likewise, the use of disinfectants has increased dramatically in response to the worldwide pandemic, and antiseptics are increasingly important in hospital settings.

Attributes And Action Of Biocides

Biocides differ in their chemical structure, properties, and spectrum of activity. To ensure they are used correctly, it is important to understand what they are needed for as there is no perfect biocide. Biocides are selected based on the intended use and their characteristics such as toxicity, corrosiveness, and spectrum of activity. Examples of commonly used biocides are aldehydes (glutaraldehyde and formaldehyde), peroxides (hydrogen peroxide), halogen releasing agents, biguanidines, quaternary ammonium compounds, phenolics and alcohols. 

What Are Biocides Used For?

Biocides have a long history beginning with food and water preservation and wound management.

With time, biocides found use in many industries and products and have become an inseparable part of our lifestyle. The following are a few listed industries with biocide applications.

• Healthcare: The healthcare industry depends heavily on biocides, where they are used for sterilization of medical devices, disinfection of surfaces and water, and skin antisepsis. 

• Pharmaceuticals: Biocides are used as preservative to preserve drugs and in some vaccine formulations.

• Biotechnology: Biocides are used as a preservative in biological products such as immunoglobulin solutions, chromatography resins and other reagents used in laboratory. 

• Cosmetic industry: Biocides are used as a preservative and antimicrobial agent in making lotions, creams, face wash and cleansing conditioners. Their use in the cosmetic industry is increasing with the increasing demand for high-quality products with cleansing and sanitizing properties to protect the consumer from skin infections.

• Domestic use products: Biocides are routinely used in domestic products such as washing powder, washing liquid, some toothpaste, mouth wash, fabric, plastics, and household cleaning products. 

• Food industry: Biocides are used extensively in the food industry to preserve food items. As preservatives, biocides increase the shelf life of food items by protecting them from deterioration by microorganisms. They are also used to disinfect production plants and food containers, as well as to decontaminate carcasses. 

• Water treatment:  Biocides are used in water treatment, both in the production of drinking water and in wastewater treatment. These are used at the waterworks to maintain the microbiological quality of water before its distribution, by sustaining total counts of microorganisms at an acceptable level and eliminating the pathogenic microorganisms. Chlorine was used widely in the past century for drinking water treatment; however, since it forms halogenated byproducts, it has been replaced with other oxidizing agents such as ozone or chlorine-dioxide. Many wastewater treatments plants include a final step of disinfection with chlorine biocide.

• Miscellaneous: Biocides are used in many other industries and products such as animal husbandry, agriculture, paper industry, used in paints, wood, and furniture.

The Pros And Cons Of Using Biocides

Although biocides are necessary for maintaining the integrity of a diverse range of products, their rampant use poses a risk to the environment. Furthermore, some studies suggest that excessive use of biocides can promote antibiotic resistance in bacteria. Thus, there is a need to strike a balance, and the use of biocides should be promoted only in areas where it is of utmost necessity.

Scope Of Biocides

The biocide market is an ever-increasing one due to the increasing numbers of applications for biocides. It is reported that the biocide market size exceeded 11.15 billion USD in 2019 and is only expected to grow.