Toxic compounds in herbicides without glyphosate

Area of Science:

• Environmental Chemistry
• Toxicology
• Agricultural Science

Background:

• Glyphosate, a widely used herbicide, has faced bans in some regions.
• Alternative herbicides using acetic acid, pelargonic acid, caprylic acid, capric acid, or benzalkonium chloride have been introduced.
• Concerns exist regarding the safety and composition of these glyphosate-free formulations.

Purpose of the Study:

• To analyze 14 marketed herbicidal products in Europe that replaced glyphosate.
• To quantify levels of heavy metals, polycyclic aromatic hydrocarbons (PAHs), and essential minerals in these formulations.
• To assess compliance with European Union regulations regarding pesticide safety and labeling.

Main Methods:

• Analysis of 35 heavy metals, 16 PAHs, and essential minerals using gas chromatography and inductively coupled plasma mass spectrometry.
• Testing of 14 commercial herbicidal formulations marketed in Europe.
• Quantification of detected contaminants and comparison with admissible levels for water and environmental safety.

Main Results:

• Heavy metals (silicon, arsenic, lead, iron, nickel, titanium) detected at levels up to 39 mg/L, significantly exceeding admissible limits.
• Polycyclic Aromatic Hydrocarbons (PAHs), including carcinogens like benzo(A)pyrene, found at levels from 32-2430 μg/L in 12 of 14 samples.
• Low levels of glyphosate detected in two samples; detected toxic compounds did not enhance herbicidal efficacy.

Conclusions:

• Glyphosate-free herbicides contain undeclared toxic heavy metals and PAHs at potentially harmful concentrations.
• These contaminants violate European Union pesticide regulations and pose risks to human health and the environment.
• Further investigation into nanoparticle presence and long-term exposure effects is warranted.