Triclocarban is used as an antimicrobial agent used in personal care products such as soaps. It was recently banned from use in over-the-counter antimicrobial soaps in the USA.
Previous studies have shown that triclocarban is very toxic to aquatic life. In fish, studies have been conducted on multiple species. One study found a low level (0.005 mg/L) of triclocarban, over 35 days, reduces the hatchability of eggs and post-larval growth in fathead minnow. The second study found that, after nine days, triclocarban (at 0.024 mg/L) has similar effects in zebra fish, reducing the hatchability of eggs and larvae survival.
A new study has looked further at the toxicity of triclocarban to zebra fish embryos – before they reach the larval stage. The authors found that, after only 96 hours, triclocarban (at 0.03 mg/L) decreased embryo survival. At 120 hours, survival was decreased by around 20%. Decreased heart rates were also observed, as well as reduced hatchability.
Together, these studies provide evidence of significant toxicity to fish over short exposure periods at low levels. Triclocarban is also not readily biodegradable and often detected in environmental waters. Many companies around the world are now phasing out the use of this chemical.