Upstream-downstream pollution gradient of carbendazim in Pazarsuyu (Giresun) stream: Spectral shift signatures and synergistic genotoxic and meristematic responses in Alliumcepa.

Environmental CBZ concentrations increase from non-detectable upstream to 8.53 ± 1.47 ng/mL downstream in Pazarsuyu Stream, indicating cumulative pollution input.

• Why it matters: Understanding how pollutants like carbendazim interact with other contaminants in aquatic environments is crucial for accurate ecological risk assessment and protection of aquatic life.
• What they did: Researchers collected water samples from five stations along the stream, measured CBZ levels, and used Allium cepa bioassays to assess oxidative stress, cytogenetic damage, and cellular integrity, comparing natural water samples and laboratory CBZ solutions.
• The result: Both environmental samples and CBZ alone caused significant oxidative stress and DNA damage, with higher genotoxic effects observed in environmental samples, highlighting synergistic toxicity and the need to consider mixture effects in pesticide risk evaluations.