Human Health

Well researched and proven to be safe

Triclosan has become one of the most researched antimicrobial active substances in terms of its impact on human safety and the environment when using the recommended dosage in health and personal care applications. The US Environmental Protection Agency (EPA) has carried out extensive assessments of Triclosan as part of the RED (registration eligibility document) review process and has affirmed that there are no human health issues, including cancer, resulting from exposure to Triclosan.

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No endocrine effects on living organisms

A wealth of scientific data, including a multi-generation reproduction study in rats and several developmental (teratology) studies three animal species, confirms that Triclosan does not cause malformations and has no effect on fertility in either animals or humans (Scientific Committee on Consumer Products: Opinion on Triclosan, 2009). A study performed by the US EPA in female weanling rats was designed to elucidate the mechanism of action of Triclosan on thyroid hormone homeostasis (Paul et al., 2010). This study confirmed the effect on thyroid hormones found in male rats (Zorrilla et al., 2009) that did not influence the onset of puberty and found evidence for upregulation of hepatic catabolism. The rat is more sensitive to changes in thyroid hormone homeostasis compared to man due to a missing binding protein with concomitant shorter thyroid hormone plasma half-life. The data in weanling rats combined with the above stated 2-generation (Scientific Committee on Consumer Products: Opinion on Triclosan, 2009) and teratology studies (Scientific Committee on Consumer Products: Opinion on Triclosan, 2009) suggest that effects on thyroid hormone homeostasis are below a threshold effect and can be viewed as adaptive. The data in weanling rats were nevertheless used in a risk assessment performed by the US EPA (Scientific Committee on Consumer Products: Opinion on Triclosan, 2009). The agency calculated a margin of exposure of ~13,000 fold when comparing daily intake and effect level where normally a factor of 100 is required (Rodricks et al., 2010). Studies in the literature also pointed to effects of Triclosan on the thyroid hormone mediated frog metamorphosis. BASF have recently conducted several amphibian metamorphosis (on both Xenophus laevis and Silurana tropicalis) in order to address this concern (Fort et al., 2010; Fort et al., 2011; Fort, Mathis, Pawlowski, 2011; DeLeo et al., 2011). All studies conducted were carried out according to GLP and in accordance to available and international accepted testing guidelines (US EPA, ASTM, etc.) using BASF (USP1)-grade Triclosan as test material. Overall, there was no evidence that Triclosan has an endocrine disrupting effect in either amphibians being exposed to environmentally relevant Triclosan-concentrations.

1United States Pharmacopeia

 

No long-term or large-scale accumulation

The European Commission’s Scientific Committee of Consumer Safety (SCCS) concluded in 2002 that if any Triclosan is absorbed by the body, it is rapidly excreted, and that no long-term or large-scale accumulation occurs. The SCCS conclusion is based on several scientific studies. Triclosan is rapidly absorbed following ingestion whereas dermally, only a fraction of the applied dose is absorbed. In fact, even from leave-on products, less than 10% enter the human body. Once absorbed, Triclosan is almost completely metabolized in all species tested to date which include rodents, rabbits, dogs, monkeys and humans. Excretion of the metabolites occurs mostly via urine in humans with an elimination half-life of less than a day. Because Triclosan is completely recovered in feces and urine, there is no indication for a deep compartment of high capacity, i.e. Triclosan does not accumulate in the human body (Rodricks et al, 2010).

 

Not carcinogenic

Triclosan is not considered a human carcinogen. The US Food and Drug Administration (FDA) reviewed similar studies and reached the same conclusion. Similarly, the Australian National Industrial Chemicals Notification and Assessment Scheme (NICNAS) published their conclusion that the use of Triclosan in consumer products is not a cause for concern (NICNAS, 2009).

No evidence of bacterial resistance

In more than 40 years of Triclosan usage, there is no evidence that Triclosan usage causes resistance in bacteria under real-life conditions. The Scientific Committee on Consumer Safety (SCCS) of the European Commission released their opinion about Triclosan and antimicrobial resistance on 22 June 2010, stating that: “Triclosan is the most studied biocide with respect to bacterial resistance with a level of information commendable to other biocides” (Scientific Committee on Consumer Safety: Opinion on Triclosan: Antimicrobial Resistance. SCCS/1251/09, 22 June 2010).

 

An assessment by the Australian National Industrial Chemicals Notification and Assessment Scheme concluded that there is no evidence that the use of Triclosan is leading to an increase in Triclosan resistant bacteria populations or that there is any increased risk to humans regarding antibiotic resistance” (Australian Government. Department of Health and Ageing. NICNAS: “Triclosan”; Priority Existing Chemical Assessment Report No. 30. ISBN 0-9803124-4-2. January 2009).

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