Challenges and risks associated with impurity profiles in technical grade crop protection products - the case of Afidopyropen and Emamectin benzoate

The safety of crop protection products and their safe use is of paramount importance and requires that crop protection products are consistently marketed and used worldwide in the required registered quality. To meet these high-quality requirements, the highest demands must be placed on the production and purification of technical-grade crop protection products. 

In this context, impurity profiles are of utmost importance, as unknown impurities at higher than registered concentrations may pose new unknown toxicological risks to users, consumers, and the environment. Particularly high demands are placed on the production and purification of technical grade semisynthetic derivatives of fermentatively derived natural products to meet the required regulatory specifications, to ensure that relevant impurities do not exceed maximum allowable concentrations, to ensure the safe use of such products, and to eliminate any unknown product safety risks. 

The challenges associated with the manufacture and purification of Afidopyropen and the product safety risks associated with various qualities of technical grade Emamectin benzoate are discussed in detail in a recent report written by Peter Maienfisch, which was published in Advanced Agrochem.

The research found that the challenges in the production and purification of Afidopyropen illustrate well the difficulties in developing a suitable manufacturing process that delivers large quantities of the technical-grade product in the required specifications at acceptable cost.

As in the case of Afidopyropen, the production of technical grade Emamectin benzoate requires a high quality and reliable manufacturing and purification process to ensure that the registered product specification is achieved and to allow safe and responsible use of the material produced.

Today, various technical grade Emamectin benzoate materials are available on the market, produced and purified by different manufacturers. Technical grade Emamectin benzoate from four different manufacturers were analyzed and only one manufacturer's material was found to be within the registered specification. Unknown impurities with unknown product safety profiles were detected in technical grade Emamectin benzoate from the other three manufacturers at concentrations above 0.1% (w/w), and these results raise serious concerns about the safe use of products manufactured and sold by these manufacturers. It is suggested that regulatory authorities around the world take appropriate measures to ensure that all technical grade crop protection products on the market strictly comply with registered specifications.

Read the full report here.