未落地的雪看起來是那么潔白無瑕，有些人甚至用新鮮的雪加入牛奶和糖做成冰淇淋，看上去十分誘人。那么看上去干凈的雪真的能吃嗎？吃雪是否安全？本文告訴你答案。

From little flurries to full-scale blizzards, it’s not unusual for snow to fall come winter. During the cold weather months, some folks like to share recipes for how to make snow ice cream and other treats that use fresh powder as a base, adding milk, sugar, and toppings.

從小雪花到暴風雪，冬天總要下幾場雪的。在寒冷的日子里，有些人喜歡分享用雪做冰淇淋和其他甜點的食譜，在新鮮的雪中加入牛奶、糖，撒上澆頭。

Obviously, no one is recommending anyone scoop up a bowlful of snow idling on the side of the road, full of salt, muck, and other unpleasantness. But it does beg the question: Is any snow actually safe to consume?

顯然，沒有人會建議你從馬路邊舀一碗雪來做美食，那里的雪摻雜著鹽粒和淤泥，還有其他惡心的東西。但是這也引發了一個問題：有沒有可以安心食用的雪？

While you may assume snow that’s freshly fallen and collected in an undisturbed area—even a cup set out for that purpose—is free of any contaminants, don’t be so sure. According to meteorologist Mary Scarzello Fairbanks, snow isn’t all that pristine. It’s formed when water droplets freeze around some dust or debris in the air, forming an ice crystal that continues to collect water vapor and form a snowflake.

你可能認為雪是從天上剛落下的，而且是在一個不受打擾的地方收集到的，甚至可能直接落入一個事先放好的杯子里，用這里的雪應該是沒有任何污染的吧？不要那么肯定。氣象學家瑪麗·斯卡澤羅·費爾班克斯表示，雪并沒有那么干凈。雪是水珠與空氣中的塵?；蛩槠嘟Y合后凝結而成的冰晶，在下落過程中繼續吸收水蒸汽，多個冰晶聚集在一起就形成了雪花。

When it falls, it will also collect things hanging in the air, including dirt, soot, and even bacterial particles. Depending on the region, snow could also contain sulfates, nitrates, formaldehyde, mercury, or pesticides. If it’s windy, snow could even mix with dirt kicked up from the soil before settling. A 2015 study published in the journal Environmental Science: Processes & Impacts even demonstrated how snow could mix with gasoline exhaust. This all means that, theoretically, your snow ice cream could have some pretty disgusting “toppings.”

當雪花落下時，還會吸收空氣中的懸浮物，包括灰塵、煤煙甚至細菌。有些地區的雪可能還會含有硫化物、硝酸鹽、甲醛、水銀或殺蟲劑。如果風大的話，雪花甚至會與從泥地上揚起的塵土混合在一起。2015年發表在期刊《環境科學：過程與影響》上的一篇研究報告證實，雪中甚至會混入汽油車排放物。這一切都意味著，從理論上來說，你的鮮雪冰淇淋可能會包含一些相當惡心的“澆頭”。

At the same time, there doesn’t seem to be a surge of reports of illnesses related to snow consumption. Assuming you don’t consume a huge quantity of it, it’s unlikely that whatever contaminants might be in the snow will be present in large enough amounts to cause problems. While no one is technically advocating for snow ingestion here, just a small bite will probably be fine.

與此同時，關于吃雪引發的疾病似乎沒有太多報道。只要你不吃太多雪，雪中可能包含的任何污染物都不足以致病。嚴格意義上，我們并不建議你吃雪，但是吃一小口應該也無妨。

Eating snow in an emergency is another matter. The Centers for Disease Control and Prevention (CDC) warns against snow snacking for anyone stranded, such as hikers, because it can lower one’s body temperature. In cases where there is a water supply issue, the CDC says it’s safe to take collected snow and boil it to kill off any germs.

在緊急情況下吃雪則是另外一回事。美國疾病控制和預防中心警告任何陷入困境的人（比如徒步旅行者）不要吃雪，因為吃雪會降低體溫。美疾控中心指出，在缺水的情況下可以收集干凈的雪將其煮沸，殺滅細菌后再喝，這樣才安全。

英文來源：Mental Floss

翻譯&編輯：丹妮