Zebrafish swims in toothpaste, questioning triclosan's safety

Is Triclosan the Silent Saboteur in Your Self-Care Routine? What Science Reveals

Reese Marlowe in Science & Nature August 2025 • 4 min read.

"Dive into the surprising world of zebrafish research and uncover the potential risks of triclosan, a common antimicrobial agent lurking in your everyday products."

In today's world, where cleanliness is next to godliness, antimicrobial agents have become ubiquitous in our daily lives. One such agent, triclosan (TCS), has infiltrated a wide array of personal care products, from toothpaste and hand soaps to cosmetics and even clothing. But amidst the promise of hygiene and protection, a growing body of research is raising concerns about the potential dark side of triclosan. Could this seemingly benign compound be silently sabotaging our health and the environment?

Triclosan's widespread use has led to its detection in various environmental compartments, including surface water, soil, and aquatic species. Moreover, it has even been found in human tissues and fluids, raising questions about its potential long-term effects on human health. As scientists delve deeper into the mechanisms of triclosan's action, evidence is emerging that suggests it may not be as harmless as we once thought.

Enter zebrafish, a tiny freshwater fish that has become a powerful model organism in toxicological research. With their genetic similarity to humans and transparent embryos that allow for easy observation of developmental processes, zebrafish offer a unique window into the potential effects of environmental contaminants like triclosan. Recent studies using zebrafish are shedding light on the potential toxic effects of triclosan, challenging its safety and prompting a closer look at its role in our self-care routines.

Zebrafish Uncover Triclosan's Hidden Dangers

Zebrafish swims in toothpaste, questioning triclosan's safety

A groundbreaking study published in Aquatic Toxicology utilized zebrafish to investigate the potential toxic effects of triclosan on liver cells and developing embryos. The researchers exposed zebrafish liver cells (ZFL) and zebrafish embryos/larvae to varying concentrations of triclosan and meticulously observed the effects on cell viability, gene expression, and developmental milestones.

The results of the study revealed a concerning pattern of toxicity associated with triclosan exposure. The researchers found that triclosan significantly impacted zebrafish embryos and larvae. The embryos experienced:

Delayed hatching.
Increased mortality, particularly in newly hatched larvae.
Inhibited liver function.

These findings suggest that triclosan can interfere with critical developmental processes and liver function in zebrafish. Furthermore, the study's investigation into gene expression revealed that triclosan disrupted the expression of genes involved in metabolism and thyroid hormone regulation. Though the study indicated that TCS is potentially hepatotoxic without disruption of thyroid or estrogen signalling.

Rethinking Our Self-Care: A Call for Safer Alternatives

The zebrafish research highlights the potential risks associated with triclosan exposure, prompting a reevaluation of its widespread use in personal care products. As consumers, it is crucial to be aware of the potential health and environmental consequences of our choices and to seek safer alternatives. By opting for triclosan-free products and supporting brands committed to transparency and sustainability, we can protect ourselves, our families, and the planet from the potential harm of this ubiquitous antimicrobial agent. While further research is needed to fully understand the long-term effects of triclosan, the evidence is mounting, urging us to rethink our self-care routines and make informed decisions that prioritize health and environmental stewardship.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1016/j.aquatox.2017.08.009, Alternate LINK

Title: Toxic Effects Of Triclosan On A Zebrafish (Danio Rerio) Liver Cell Line, Zfl

Subject: Health, Toxicology and Mutagenesis

Journal: Aquatic Toxicology

Publisher: Elsevier BV

Authors: Zhou Zhou, Jie Yang, King Ming Chan

Published: 2017-10-01

Everything You Need To Know

What is triclosan, and why is it found in so many personal care products?

Triclosan (TCS) is an antimicrobial agent commonly found in personal care products like toothpaste, hand soaps, cosmetics, and even clothing. Its widespread use is due to its ability to kill bacteria, promising enhanced hygiene and protection. However, its presence in numerous products and the environment is raising concerns about potential adverse effects on human health and the environment.

Why are zebrafish used to study the effects of triclosan?

Zebrafish are used in toxicological research because they share genetic similarities with humans, and their transparent embryos allow scientists to easily observe developmental processes. This makes them ideal for studying the effects of environmental contaminants like triclosan. Studies on zebrafish help uncover how triclosan exposure impacts cell viability, gene expression, and developmental milestones, providing insights into potential health risks.

What specific health problems have been linked to triclosan exposure in zebrafish studies?

Research using zebrafish has revealed that triclosan exposure can lead to several adverse effects, including delayed hatching, increased mortality in newly hatched larvae, and inhibited liver function. Furthermore, these studies indicate that triclosan can disrupt the expression of genes involved in metabolism and thyroid hormone regulation, though the research suggests TCS is potentially hepatotoxic without disruption of thyroid or estrogen signaling.

What are the potential long-term health implications based on the gene expression disruption seen in zebrafish exposed to triclosan?

Based on zebrafish studies, the disruption of gene expression, specifically in areas of metabolism and thyroid hormone regulation, suggests that triclosan could potentially interfere with essential physiological processes in humans. While the study indicates that TCS is potentially hepatotoxic without disruption of thyroid or estrogen signaling, further investigation is needed to fully understand the long-term effects of triclosan exposure on human health, particularly concerning endocrine disruption and metabolic disorders.

How can consumers reduce their exposure to triclosan in everyday products?

To reduce exposure to triclosan, consumers can actively seek out triclosan-free personal care products and support brands that are committed to transparency and sustainability. Checking product labels for triclosan is crucial. Choosing products with natural or less harmful antimicrobial alternatives can help minimize both personal and environmental contamination. Further research into identifying safer alternatives to triclosan is essential for developing effective and health-conscious hygiene practices.