This is the VOA Special English Development Report.

World No Tobacco Day is celebrated each 31st of May. The observance is meant to bring attention to the growing use of tobacco and its deadly effects. The World Health Assembly established the event in 1987. This year, special attention is being given to the harmful effects of tobacco marketing to women and girls.

The World Health Organization says tobacco kills nearly five and a half million people a year -- another victim every six seconds. Tobacco use is a top cause of death worldwide.

One billion people smoke. More than 80 percent of tobacco users live in low and middle income countries.

The W.H.O. says the tobacco industry has increasingly directed its marketing campaigns at women and girls. Women currently represent about 20 percent of smokers. But tobacco use among girls is increasing.

Data collected from 151 countries show that about seven percent of young girls now smoke. That compares with 12 percent of boys. In some countries, however, the rates are almost equal.

Almost 170 countries have signed a treaty called the Framework Convention on Tobacco Control. The W.H.O. is calling on those governments to ban tobacco advertising to the fullest extent possible and to do more to protect women.

The agreement seeks to reduce the demand and supply of tobacco products. This year marks the fifth anniversary since the treaty went into effect.

Eighty percent of the signers have banned the sale of tobacco products to young people. Seventy percent have required health warnings on tobacco products.

The W.H.O. estimates that tobacco use caused 100 million deaths in the 20th century. If current rates continue, that number could reach one billion in this century.

Events are planned in a number of countries to mark World No Tobacco Day. Many of the events are aimed at persuading people, especially the young, not to start smoking. Others aim to educate people about the many health benefits of quitting.

And that's the VOA Special English Development Report, written by June Simms. We have a link to a list of activities for World No Tobacco Day on our website, voaspecialenglish.com. And while you're there, tell us if you have been able to quit smoking, and what advice you might have for others. You can also post comments on Facebook at VOA Learning English. I'm Bob Doughty.

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（来源：VOA 编辑：陈丹妮）