Experts from the Chinese Research Academy of Environmental
Sciences, Chinese Academy of Sciences, Peking University and
Tsinghua University have been discussing the bloom of blue-green
algae afflicting Taihu Lake.
They have identified the algae as microcystis.
Professor Yu Shunzhang from Fudan University told China
Daily that microcystis is the most poisonous of blue-green
algae, giving out microcystin, a poisonous substance harmful to
both plant and animal life.
The Chinese Academy of Sciences' ecology center tested water
from the lake, from which the Gonghu Tap Water Firm sources its raw
material.
They discovered that every liter of water contained 0.06 mg of
microcystin. The national and World Trade Organization quality
standard for surface water is 1 mg per liter.
"Since we have tested lake water, it is safe to assume that the
tap water in Wuxi is very safe," Yu said. "And water from the lake
goes through several processing procedures before it becomes tap
water."
According to information from Wuxi's disease control center,
there has been no change in the frequency of epidemic diseases
related to drinking water this year.
Yu attributed the bloom to a high concentration of nutrients off
which the blue-green algae feed. The condition is known as rich
nutritional pollution.
Industrial pollution and human waste have introduced large
amounts of phosphorus into the water, which nourishes the algae.
However, rich nutritional pollution has become increasingly evident
in the past few years. Experts warned that if pollution emissions
cannot be controlled in the short term, blooms of blue-green algae
will happen again.
A man surnamed Ding from Wuxi was arrested on June 6 for
distributing mobile phone text messages that claimed Taihu Lake
contained large amounts of cancer-causing chemicals, which was
later proved to be untrue.
The text message quickly made its way around Wuxi over the
course of several days, causing a general panic. Police traced the
message back to Ding before making an arrest.
The message said Taihu water contained "200 times more harmful
material than the national standard", but the Wuxi disease control
center rejected these claims.
The temperature in Wuxi has risen past 31 ℃?in the past few days. The heat wave
could also lead to fresh blooms of blue-green algae, experts
warned.
(China Daily June 13, 2007)
