含高劑量氧化鋅?罐裝食品或傷害消化系統大綱

The next time you opt for canned foods such as corn, tuna, asparagus or chicken, think twice. They may contain zinc oxide that can potentially damage your digestive system, warn researchers.

下次你選擇吃罐裝食品，比如玉米罐頭、金槍魚罐頭、蘆筍罐頭或者雞肉罐頭之前，要三思而行。研究人員提醒說，這些罐裝食品中含有的氧化鋅可能會損害你的消化系統。

The findings showed that nanoparticles of zinc oxide present in the lining of certain canned goods, usually considered good for its antimicrobial properties and preventing staining of sulfur-producing foods, may negatively affect the way in which human digestive tract operates.

研究顯示，某些罐裝食品包裝內層含有的氧化鋅納米微粒對人類消化道的運轉有壞處。人們通常認爲這些氧化鋅納米微粒具有抗菌特性，可以防止產硫食品的污染。

"We found that zinc oxide (ZnO) nanoparticles at doses that are relevant to what you might normally eat in a meal or a day can change the way that your intestine absorbs nutrients or your intestinal cell gene and protein expression," said Gretchen Mahler, Associate Professor at the Binghamton University in the New York.

紐約賓漢姆頓大學副教授格蕾琴?馬勒說：“我們發現氧化鋅納米微粒的劑量與你在一頓飯或一天中通常吃的東西有關，它會改變腸道吸收營養素的方式，以及你的腸細胞基因和蛋白質表達。”

Researchers found that canned food contained 100 times the daily dietary allowance of zinc.

研究人員發現，罐裝食品的鋅含量是平均每天應攝入量的100倍。

"They tend to settle onto the cells representing the gastrointestinal tract and cause remodelling or loss of the microvilli, which are tiny projections on the surface of the intestinal absorptive cells that help to increase the surface area available for absorption," Mahler added.

馬勒補充說：“氧化鋅納米微粒容易聚集在胃腸道細胞上，改變小腸吸收細胞表面微絨毛的結構甚至減少微絨毛數量，這些微絨毛能增加腸道可吸收表面的面積。”

This loss of surface area tends to result in a decrease in nutrient absorption.

腸道可吸收表面面積的減少會減弱營養吸收功能。

Some of the nanoparticles also cause pro-inflammatory signaling at high doses, and this can increase the permeability of the intestinal model, the researcher said.

馬勒說，一些氧化鋅納米微粒在高劑量下還可能觸發促炎信號，從而增加腸道模型的滲透率。

In other words, it can even allow the passage of compounds that are not supposed to pass through into the bloodstream.

也就是說，這會允許原本不該通過的化合物進入血液。

The study, published in the journal Food & Function, looked at how many particles might be transferred into the canned food.

這項研究報告發表在《食品與功能》期刊上，論述了罐裝食品中會滲入多少氧化鋅納米微粒。

"Our model shows that the nanoparticles do have effects on our body in vitro model, and that understanding how they affect gut function is an important area of study for consumer safety," Mahler said.

馬勒說：“我們的體外模型顯示，（氧化鋅）納米微粒對人體確有影響，理解它們如何影響腸道功能對消費者安全具有重要意義。”