A chemical that ripens fruits and vegetables does no harm to human health, experts said following recent reports about a ripener used in several provinces.

"There is no problem with using ethephon to ripen fruits. This plant growth regulator is completely the same as hormones produced by plants themselves when they get ripe," Luo Yunbo, dean of the College of Food Science and Nutritional Engineering under China Agricultural University and an expert of plant physiology, told China Daily on Monday.

"The chemical is safe enough that there is even no need for detection," Luo said.

The national standard for the amount of residue of the chemical is two milligrams in every kilogram of fruit, and experts said the actual dosage is far below that level, as overuse benefits neither farmers nor their fruit.

"Overdose may make fruit ripen too rapidly and even rot, and will scorch the skin of fruit, which will harm sales for vendors," Luo said.

Experts said people should not worry about the use of the ripener because it has been used worldwide for decades.

"China learned the use of the hormone from the United States and Japan, which is a pioneer in research and use of plant growth accelerators and regulators. It's an achievement in science and technology," said Fan Zhihong, a nutrition and food safety professor with China Agricultural University.

Ethephon, an organic compound, is an agricultural plant growth stimulant that is sprayed on 70 or 80 percent ripe fruit after they have been picked. It gives off ethylene to facilitate ripening.

Some fruit, such as bananas, will rot instead of ripen without such a ripener, according to experts.

"The traditional way to ripen bananas is to put them together with mature apples, which can release ethephon to help bananas ripen, or ripen them by fuming with joss sticks. But these two ways may give bananas uneven color when they turn yellow, and the fruit will never have achieved mass production," Luo said.

Ethephon has been under the spotlight after reports came out saying vegetables, including tomatoes and cucumbers in Shandong, Anhui and Jiangsu provinces, had the ripener applied before they matured to increase production and make them marketable.

"Actually this chemical will not lead to a larger output at all, and it does not work on cucumbers," Luo said.

"There's no need to use chemicals to ripen tomatoes now, as they turn red easily in hot weather. Some farmers use that in winter," said a vendor surnamed Dai in a food market in Beijing's Chaoyang district.

People interviewed by China Daily said it is easy to stir panic about additives or growth accelerators, as food safety is a major concern.

"I avoid buying vegetables that look particularly exquisite and flawless to dodge suspicious chemicals," said Lin Jing, a Beijing woman purchasing vegetables in the market.