Green Tea offsets the mutations caused by tobacco
The Ames test named after its inventor, Doctor Bruce Ames, inexpensively and quickly helps indicate
a chemicals ability to cause cancer. In the test, a specifically engineered strain of the bacteria
Salmonella typhimurium, is exposed to gradually increasing concentrations of a chemical to see at
what level of exposure the chemical causes harm to the bacteria's DNA - this is known as mutagenicity
as in mutation. Since mutation (a change in the DNA structure) is close to carcinogenicity, or the
ability to cause cancer, this is an accepted indication of the safety of a suspected chemical. In
this test a water extract of tobacco caused mutation of the bacteria's DNA at 50mg per plate of
bacteria (50mg is a very small amount). Green Tea polyphenols inhibited the mutagenic effects of the
tobacco, the more Green Tea extract, the greater the protection (e.g. at 5mg per plate, the Green
Tea polyphenols inhibited mutagenicity by 50%). In rats, the Green Tea extract inhibited the urinary
mutagenicity caused by tobacco extract. The Green Tea extract inhibited mutagenicity in a number of
ways. The study is published in the March 2005 issue of the journal Phytomedicine.
Commentary by Jerry Hickey, R.Ph.
The Green Tea extracts ability to decrease tobacco induced mutations in the urinary tract
is good news considering that tobacco is a major risk factor for bladder cancer.
Water-Damaged building triggers breathing problems and asthma
In a study of workers in one previously water damaged office building it was found that the
rate of adult onset asthma in employees was greater than 3 times the normal rate according to
government researchers. Indoor damage due to leaking and flooding can lead to the growth of
mold and other bacteria, and the population of dust mites explodes. The researchers estimated
that up to 12 percent of sick days could be attributed to the water-damaged environment. 103 of
888 employees in the building had adult onset asthma, a very high rate and the rates of wheezing,
nasal and eye symptoms were very high. Among workers who were symptom free, about 50% had
developed symptoms within the next nine months. The study appears in the April 2005 issue of
the journal Environmental Health Perspectives.