TriclosanCAS 3380-34-5

FDA-banned in OTC antibacterial soap in 2016 for endocrine disruption — still in plastics, paint, and textiles.

Other Antimicrobials substances:MethylisothiazolinoneMethylchloroisothiazolinoneBenzisothiazolinoneOctylisothiazolinoneSilver NanoparticlesZinc PyrithioneIodopropynyl ButylcarbamateDidecyldimethylammonium Chloride
Building products and consumer items containing Antimicrobials family members
Triclosan belongs to the Antimicrobials family — products shown above commonly contain one or more substances from this family

Toxic Chemical Databases

Substance-specific listings — these flags are for Triclosan alone, not for the broader family.

LBC Red List
Listed
Prop 65
Listed
IARC
Not Listed
NTP RoC
Not Listed
GSPI
Listed
REACH SVHC
Listed
TSCA
Listed

Chemical Type

Chlorinated Phenol Antibacterial

Chemical Description

Triclosan is a chlorinated aromatic biocide developed in the 1960s as a hospital disinfectant. Its toxicology became headline news in 2016 when the FDA banned it from over-the-counter antibacterial soaps after finding no health benefit over plain soap and clear endocrine-disruption signals — particularly thyroid hormone suppression. The molecule persists in human serum at detectable levels in nearly every US resident sampled. Despite the soap ban, triclosan remains widely used as an antimicrobial additive in plastics (cutting boards, refrigerator linings), paint, fabric treatments, and personal-care leave-on products. Hits a particularly nasty failure mode under UV exposure: photolytic conversion to dioxins.

Biological Activity

Severity scores specific to this substance, NOT the parent family average. Differences between siblings are real and meaningful.

Endocrine
9/10
Reproductive
7/10
Developmental
7/10
Immune
7/10
Skin
6/10
Cancer
5/10
Liver/Kidney
6/10
Cardiovascular
4/10
Neurological
4/10
Respiratory
3/10

Top Health Consequences

Pathways of Exposure

Building Materials with Triclosan

Listed alphabetically — product categories where this specific substance appears.

Want to screen a specific product? Drop the manufacturer's SDS into our SDS Toxic Chemical Screener — it screens this substance (CAS 3380-34-5) against all seven databases shown above.

How We Keep Triclosan Out of a House

Avoiding Triclosan is only half of it. The replacement has to work in a mold free, airtight, PHPP-modeled assembly as well — and finding materials that do both is most of what we do.

If you want a house specified this way from the start, or an existing house assessed for what is already in it, that is the work we do. Earth Bound Homes builds in Atherton, Palo Alto, Redwood City and across the San Francisco Bay Area.

Talk to us about your projectSee the homes we have built