By Natalie Yau

More dioxin may mean less sperm

Endocrine disrupting chemicals can have great influences on human reproductive ability.

There are many endocrine disrupting chemicals or potential endocrine disrupting chemicals in the surroundings, say, dioxins, PCBs, and PAHs.

Prof. Chan King Ming of the Department of Biochemistry at The Chinese University of Hong Kong contaminated food and polluted air are two major ways people are exposed to dioxin.

The excessive industrial use of dioxins in the past has contaminated nearby water sources and river bed sediments.

Chemical processes in the natural environment transform dioxins to environmental estrogen, which is similar to estrogen in the human bodies, but exists in the environment.

It gradually enters the food chain and is passed to human beings.

“Dioxins are insoluble. They accumulate in the fat layer of marine creatures.

“Chemicals continually accumulate in our bodies and are not excreted,” said Prof. Chan.

Such environmental estrogen can distort the proper functioning of male sex organs.

Sperm counts thus drop. Burning petroleum and its by-products, like diesel, adds dioxins to the atmosphere in the form of suspended particles.

Incineration of rubbish produces dioxins as well.

The Environmental Protection Department said in 2000 that dioxin levels in Hong Kong pose no health risk.

The ambient levels of dioxin in Hong Kong are similar to those in other urban areas.

The government also pointed out that the Chemical Waste Treatment Centre at Tsing Yi has adopted the world’s most stringent dioxin emission standard.

In addition, no obvious increases in the ambient dioxin levels has been recorded.

Prof. Chan said people need not worry too much about the problem of accumulation and possible dangers of the strong toxicity.

Said he: “Up till now, scientists have not proved the direct linkage between dioxins and the drop in sperm counts.

“There are many factors leading to the drop in male sperm counts. We should not over-emphasise a single factor.”

Mr. Chau Siu-cheong, director of Produce Green Foundation, said it is a “scientific truth” between the two variables.

Said he: “Sperm counts of men have dropped about 50 percent in the past few decades as a result of environmental pollution.

“About 30 to 40 percent of males in Hong Kong are impotent.

“Within several decades, the rate will probably rise to 80 percent.”

Pollution in all spheres

Mr. Chau said there are too many “fake” hormones in the environment.

They come from excessive industrial and agricultural use of chemicals.

They act as human estrogen, affecting the natural functioning of male’s reproductive organs.

Radiation from computers, mobile phones and microwave ovens are also harmful to human health.

Said Mr. Chau: “To protect ourselves, we should keep away from sources of radiation.”

Said Prof. Chan: “People should eat less fat because this is where dioxins accumulate. A balanced diet is preferred, while eating internal organs should be avoided.”

To alleviate the adverse effects of pollution on human health and thus reproductive capacity, Mr. Chau said there is much people can do.

Said he: “To counter air pollution, we can simply wear masks outdoors.”

Products containing organic chlorine in their production process, like bleached toilet paper and coffee filters, should be avoided.

“Having enough sleep, maintaining a pleasant mood and having spiritual goals are highly essential.

“Also, one should abstain from cigarettes and alcohol,” said he.

Dr. Tsang Po-keung is chairman of Green Power. He said the present environment is worse than it was decades ago.

Pollution caused by road traffic has overridden environmental damage imposed by secondary industries in the past.

Most factories having moved to the mainland, heavy traffic is now the main source of air pollution.

Of all sources, diesel-consuming vehicles are especially damaging.

Said Dr. Tsang: “Diesel from local gas stations is more environmentally friendly than the banned diesel from the mainland.”

Some also put the blame on pollutants from the Mainland.

Increases in the volume of suspended particles and nitrogen dioxide irritate the human respiratory system.

Patients with chronic respiratory problems — for example, asthma — are particularly affected.

Polluted indoor air

Sadly though, not only outdoor air is polluted, but also indoor air quality has also reached low levels.

Mr. Lo Well suffers from the disease of “multiple chemical sensitivity” which makes him allergic to almost all chemicals.

He said nearly everything in his room — wallpaper, carpet, curtains and clothing — may irritate his respiratory system.

“I can’t sleep at night. It’s difficult to breathe shortly after I’ve fallen asleep. My ears are painful and I feel like my lungs are burning.”

At first, doctors could not identify his illness.

He then looked through Western medical research and found out that he was suffering from the illness called “multiple chemical sensitivity”.

He said that, when heated, petroleum products start the process of “off-gassing” and emit toxic chemicals into the air.

The fact is that his bedroom contains many petroleum by-products — for instance, plastic and dyes in curtains, carpet and clothing.

He pointed out that a piece of carpet is made by plastic with over 120 kinds of toxins.

And some of them can cause cancer.

Said he: “When I have all of them removed, I feel much better and I can sleep throughout the night.

“However, my central nervous system is permanently damaged.”

Outdoor air pollution also hinders his activities.

“At times of high smog levels, I have to stay indoors or I may have respiratory problems,” he said.