an antibacterial widely used in soaps, deodorants, toothpastes and
other body-care products, reduces muscular strength, according to
a mice study.
"Triclosan is found in virtually everyone's home and is pervasive
in the environment," said Isaac Pessah, professor and head of
molecular biosciences in the University of California-Davis School
of Veterinary Medicine and principal study investigator.
"These findings provide strong evidence that the chemical is of
concern to both human and environmental health," Pessah was quoted
as saying by the journal Proceedings of the National Academy of
Triclosan is commonly found in antibacterial body-care products
such as hand soaps as well as deodorants, mouthwashes, toothpaste,
bedding, clothes, carpets, toys and trash bags, according to a
The Environmental Protection Agency in 1998 estimated that more
than one million pounds of triclosan are produced annually in the
US. Traces are present in waterways and aquatic organisms, from
algae to fish to dolphins, as well as in human urine, blood and
Investigators performed several experiments to evaluate the
effects of triclosan on muscle activity, using doses similar to
those that people and animals may be exposed to during everyday
In "test tube" experiments, triclosan impaired the ability of
isolated heart muscle cells and skeletal muscle fibres and muscle
movements, including heartbeats to contract.
Besides, the mice had an 18 percent reduction in grip strength for
up to 60 minutes after being given a single dose of triclosan.
Grip strength is a widely used to measure of limb strength.
The team also found that triclosan impairs heart and skeletal
muscle contractility in living animals.
Anaesthetised mice had up to a 25 percent reduction in heart
function measures within 20 minutes of exposure to the chemical.
"The effects of triclosan on cardiac function were really
dramatic," said Nipavan Chiamvimonvat, professor of cardiovascular
medicine at California-Davis and study co-author.
"Although triclosan is not regulated as a drug, this compound acts
like a potent cardiac depressant in our models," concluded