Adjuvants in Agrochemistry: How to Minimize Risks During Handling and Storage for Safer Application

Photo: Carl Nenzen Loven / Unsplash

Adjuvants play an indispensable role in agrochemistry – they enhance the effectiveness of pesticides, improve adhesion to plants, or reduce evaporation. Although they are often not classified as highly hazardous themselves, improper handling or storage can lead to quality degradation, loss of efficacy, or even undesirable chemical reactions. When combined with pesticides, they may also increase the risk of soil, water, or worker health contamination. This article focuses on practical guidelines for safely storing, mixing, and applying adjuvants to avoid common mistakes and maximize their functionality.

What are adjuvants and why do they require special attention

Adjuvants are auxiliary substances added to pesticide formulations to improve their efficacy, stability, or application properties. These include, for example, wetting agents, penetration enhancers, adhesives, foaming agents, or foam stabilizers. Although they do not have pesticidal effects themselves, their chemical nature—often based on surfactants, organic solvents, or polymers—entails specific risks during handling and storage. These substances may be flammable, corrosive, irritating to the skin and respiratory tract, or sensitive to moisture and temperature fluctuations.

Special attention is required for adjuvants based on organic solvents, such as alcohols or glycols, which can form explosive vapors if stored improperly. Another high-risk group includes strongly alkaline or acidic adjuvants, which can cause chemical burns upon contact with skin or mucous membranes. Therefore, it is crucial to know not only the purpose of the adjuvant in a specific formulation but also its physicochemical properties and associated safety requirements under REACH and CLP/GHS regulations.

Safe Handling of Adjuvants: Key Procedures and Protective Equipment

When handling adjuvants, it is essential to follow basic safety rules to minimize the risk of injury or contamination. Workers should be equipped with appropriate personal protective equipment (PPE), including chemically resistant gloves, protective goggles with side shields, and respirators with organic vapor filters if exposure to volatile substances is possible. For working with concentrated adjuvants, the use of protective clothing made from chemical-resistant materials, such as polyethylene or butyl rubber, is recommended.

An important step is also the correct dosing and mixing of adjuvants with pesticides. It is always necessary to follow the manufacturer's technical data sheet and adhere to the recommended ratios. Mixing should take place in well-ventilated areas or under a fume hood to prevent inhalation of vapors or aerosols. When pouring adjuvants, it is advisable to use funnels with closures and antistatic containers to reduce the risk of electrostatic discharge, especially with flammable substances. After completing the work, all tools and containers must be thoroughly cleaned to avoid cross-contamination.

Photo: Atik sulianami / Unsplash

Storage of adjuvants: conditions and organization to minimize risks

Proper storage of adjuvants is crucial for maintaining their stability and safety. Substances should be kept in their original, tightly sealed containers, which are labeled in accordance with CLP/GHS regulations, including warning symbols and safety instructions. Storage areas must be dry, well-ventilated, and protected from direct sunlight, extreme temperatures, and humidity. The storage temperature should be within the range recommended by the manufacturer, typically between 5 °C and 25 °C, to prevent degradation or the formation of hazardous by-products.

Adjuvants must be stored separately from food, feed, fertilizers, and other chemicals that could react with their components. Flammable adjuvants must be kept in separate, fireproof areas with adequate ventilation and access to firefighting equipment. For storing larger quantities, it is advisable to use shelving systems with labeling and separation of individual substance types. Regular warehouse inspections, including checks of expiration dates and container integrity, help prevent accidents and ensure that adjuvants remain effective and safe throughout their storage period.

Emergency situations and first aid in case of adjuvant exposure

Even when all safety measures are followed, accidents can occur, so it is essential to have an emergency plan in place. In the event of an adjuvant spill, the source of contamination must be immediately stopped, the area ventilated, and absorbent materials such as sand or special chemical absorbents used to prevent the spread of the substance. When handling spilled adjuvants, protective equipment must be used to avoid skin contact or inhalation of fumes.

In case of exposure to adjuvants, it is crucial to act quickly. If contact with skin occurs, immediately rinse the affected area with plenty of water and remove contaminated clothing. In case of eye contact, rinse the eye for at least 15 minutes and seek medical assistance. If vapors or aerosols are inhaled, move the affected person to fresh air and monitor their condition. In case of adjuvant ingestion, seek medical assistance and have the substance's safety data sheet available, which contains first aid information and possible antidote treatment. It is always important to inform medical personnel about the type of adjuvant the affected person was exposed to.

Photo: benjamin lehman / Unsplash

Compatibility of adjuvants with pesticide formulations: how to prevent undesirable reactions

Adjuvants are designed to enhance the efficacy of pesticide formulations, but their incorrect combination can lead to chemical reactions that jeopardize not only application effectiveness but also worker safety. Before mixing, it is essential to verify the compatibility of individual components according to the manufacturers' technical data sheets. Some adjuvants, such as those based on silicone surfactants, may react with certain active substances in pesticides, resulting in sediment formation, foaming, or even the release of toxic gases. These reactions often manifest as color changes, cloudiness, or separation of the mixture, which are clear signs that the mixture is unstable and should not be used.

To minimize risks, it is recommended to perform the so-called "jar test" – a simple laboratory test in which a small amount of adjuvant and pesticide is mixed in a transparent container and the behavior of the mixture is observed for 24 hours. If no undesirable changes occur, the mixture can be considered compatible. This test should always be conducted when changing the adjuvant supplier or the composition of the pesticide formulation. It is also important to adhere to the recommended mixing ratios, as an excessive amount of adjuvant can disrupt the stability of the mixture and increase the risk of worker exposure to toxic substances.

Training and Awareness: The Key to Safe Handling of Adjuvants in Agrochemistry

Safety when handling adjuvants is not only a matter of proper equipment but also of knowledge and responsible employee practices. Regular employee training should include not only theoretical information about the properties and risks of individual substances but also practical demonstrations of correct handling, including emergency situation simulations. Employees should be familiar with safety data sheets (SDS) and able to interpret them correctly, particularly with regard to first aid instructions, storage, and disposal. An important part of training is also raising awareness about long-term health risks, such as sensitization or chronic damage to the liver or kidneys due to repeated exposure.

In practice, implementing a "mandatory knowledge" system has proven effective, where each employee must demonstrate knowledge of basic procedures before starting work with adjuvants. This includes, for example, the correct use of personal protective equipment (PPE), procedures in case of substance spills, or safe mixing principles. Training should be repeated regularly, ideally at least once a year, and updated whenever there are changes in the substances used or regulations. Investment in employee education pays off many times over in the form of reduced workplace accidents and increased work efficiency.

Environmental aspects of adjuvant storage and disposal: how to minimize the impact on the environment

Adjuvants, like pesticides, can pose a risk to the environment if not stored and disposed of correctly. Substance leaks into soil or water sources can cause contamination and long-term ecological damage. Therefore, it is essential to adhere to strict storage principles, which include not only proper temperature and humidity conditions but also protection against mechanical damage to packaging. Storage areas should be equipped with an impermeable floor with drainage to a retention tank, which prevents substances from leaking into the sewer system or surrounding soil in the event of an accident.

Disposal of adjuvant residues and empty containers must comply with current legislation, which typically requires handing them over to a specialized company dealing with hazardous waste disposal. Residues should never be poured into sewers, soil, or watercourses, nor burned under uncontrolled conditions, as this can lead to the release of toxic substances into the atmosphere. Empty containers must be thoroughly rinsed and then disposed of according to the manufacturer's instructions. To reduce the environmental footprint, it is advisable to prefer adjuvants with a lower content of volatile organic compounds (VOCs) and those that are biodegradable, if application efficiency allows.

Need advice on selection or handling?

Every adjuvant requires a specific approach to handling and storage. GCG Group provides detailed safety and technical data sheets with recommendations for safe use for all supplied raw materials. Our experts will be happy to advise you on selecting the right type for your application and help optimize processes. Contact us – or browse our catalog of over 1,300 products right away.