Adjuvant contributes Roundup's unexpected effects on A549 cells.

Area of Science:

• Environmental toxicology
• Cell biology
• Biochemistry

Background:

• Glyphosate-based herbicides (GBHs) like Roundup® (RDP) are widely used, raising concerns about environmental and human health risks.
• The specific components of RDP responsible for its toxicity, particularly the adjuvant polyethoxylated tallow amine (POEA) versus the active ingredient glyphosate isopropylamine salt (GP), require investigation.

Purpose of the Study:

• To determine whether the RDP adjuvant POEA or the active ingredient GP is responsible for RDP's cytotoxicity.
• To elucidate the cellular mechanisms underlying RDP-induced toxicity in human lung cells.

Main Methods:

• Human lung A549 cells were treated with RDP, POEA, or GP.
• Cell proliferation was assessed.
• Intracellular biochemical assays were performed to evaluate mitochondrial membrane potential, cytochrome c release, caspase activation, PARP cleavage, and DNA damage.

Main Results:

• RDP and POEA inhibited A549 cell proliferation.
• RDP and POEA treatments induced mitochondrial dysfunction, cytochrome c release, caspase activation, PARP cleavage, and various forms of DNA damage.
• GP treatment alone did not induce these toxic effects.

Conclusions:

• The cytotoxicity and genotoxicity of RDP towards human lung A549 cells are primarily attributed to the adjuvant POEA, not the herbicidal active ingredient GP.
• This finding underscores the importance of evaluating the safety of herbicide formulations, including their adjuvants, for potential human health and environmental impacts.