Polyethoxylated Amine Research Articles

Underneath glyphosate label: possible health hazards from the exposure to co-formulants

Commercial formulations of glyphosate are mixtures of chemicals. Glyphosate is classified as the active ingredient, while some other compounds included in the pesticide mixture are categorized as ‘inert’. Active ingredients are tested in a battery of cell assay and rodent bioassays to establish health-based guidance values, such as the chronic reference dose. However, pesticide ingredients considered to be inert are generally exempt from the requirements of tolerances, although they can actually be more toxic than the declared active ingredients. It is widely recognised that glyphosate-based herbicides, such as Roundup, and the inert ingredients in formulated glyphosate-based herbicides, are more toxic than the declared active ingredient, glyphosate. The first generation of polyethoxylated amine (POEA) surfactants in Roundup was markedly more toxic than glyphosate and heightened concerns of risks to human health, especially among heavily-exposed applicators. Although these surfactants are still used in most countries, including in the United States, they have been progressively replaced by other POEA or non-POEA surfactants in the European Union. However, it is not always clear to which extent these surfactants are dealing with lingering concern over surfactant toxicity. This presentation will describe the inert ingredients present in various glyphosate-based formulations. The results of the first comprehensive study evaluating the contribution of a representative member of the new generation of surfactant to glyphosate toxicity will be presented. I will address what is known regarding the contribution of co-formulants to the health effects triggered by use of, and exposure to glyphosate-based herbicides.

Nonaqueous Processing of Silicon for Reaction‐Bonded Silicon Nitride

Ethanolic silicon suspensions, with and without a polyethoxylated amine of low molecular weight, were studied by rheological, adsorption, electrophoretic, and sedimentation methods. Pellets were pressure‐cast and nitrided to form reaction‐bonded silicon nitride. Density and binding strength in the green state relate well to rheological behavior and other collodial aspects of the suspensions used, particularly the additive's role and distribution. Density and degree of nitridation in the final state are not importantly affected by the additive's use. Its greatest benefit is to modify the binding strength in the green state. The mode by which this small molecule affects the processing of silicon consists of adsorption, combined with an increased electrostatic interparticle repulsion which increases the suspension viscosity and that of undried pellets. Although the improved binding strength is accompanied by decreased green and nitrided densities, high degrees of conversion to silicon nitride are still achieved.