Is Eating Snow Still Safe for Kids?

One of the simple pleasures of childhood is eating snow. For some time, parents have warned kids to stay away from dirty snow (particularly yellow snow). Parents are now wondering whether it is still safe for kids to eat new-fallen snow. The reason? Snow contains large quantities of Pseudomonas syringae, a type of bacteria that causes diseases in tomato and bean plants.

A scientific paper published in Science reports that microbes are more common in snow and rain than originally thought, but they also have a powerful and important role in the dynamics of climate that produce precipitation.

Although water is normally thought to freeze at zero degrees Celsius, pure water vapor in the upper reaches of the atmosphere will freeze only at temperatures colder than -35 degrees Celsius. In order to freeze at warmer temperatures, it is necessary to have nucleators — tiny particles around which water vapor will gather and freeze.

The researchers discovered that the most common nucleators are not fine dust (as traditionally thought) but bacteria, and among such biological nucleators Pseudomonas syringae is the most widespread.

The researchers analyzed 20 samples of snow taken from various places around the world, including even remote places such as Montana, the Yukon and Antarctica. Bacteria levels were high in all the samples.

Scientists have wondered what the effect of the bacteria would be on health. The author of the study, in effect, asked whether the P. syringae is a good guy or a bad guy, and then said he does not have the answer to this question.

This unanswered question thus leaves parents wondering what to do. Experts say there is not much cause for worry.

The bacteria is very ubiquitous, clarifies a member of the committee on infectious diseases of the American Academy of Pediatrics. Children practically bathe in bacteria every time they are in the playground, and what they get from snow they also get all the time from dirt.

All food is covered with bacteria, and people eat bacteria all the time, says a member of the committee on environmental health of the same pediatric academy. But most of the bacteria are killed in the stomach. For the most part, people are safe from the bacteria.

Some exceptions are noted. Babies and tots on formula don’t have enough acid in their stomach to kill the bacteria. People with cystic fibrosis also are vulnerable to Pseudomonas.

Most reassuring of all, there are no clinical reports about children becoming ill from snow eating.

Safety Tips:

• Licking the snow off the kid’s glove is likely to be fine. A “meal” of snow is probably not a good idea.

• Refrain from eating a lot of snow. It also contains particles from ordinary air pollution.

• Catching a snowflake with the tongue is OK. Eating snow that’s on the ground is not OK.