So there I was at a kid’s birthday party, my 13-month-old daughter playing merrily with her brother in the sandbox, when she suddenly decided that she was hungry. Into her mouth it went—all of the sand—and though I was up with a leap and a “No,” I was too late. I laughed nervously while furiously fishing sand out of her mouth (it’s surprisingly hard to do, by the way) as other parents looked on with a mixture of unease and relief—Gross, but thank God it wasn’t mine. My friend, the host who owned the sandbox, appeared. “Did I ever tell you,” she said, “that I think my cat poops in there?”
Kids love sandboxes. Parents do not, and for good reason. When public health–testing organization NSF International sampled 26 different items in public places—toys at doctors’ offices, children’s library books, playground sandboxes—for a 2008 study on germs, they found that sandboxes were far and away the germiest of all, harboring nearly 2,000 times more bacteria, yeast, and mold per square inch than the door handles of public restrooms.
Of course, bacteria, yeast, and mold aren’t all bad. Many are actually quite good for us. Not so for the other microbial gifts that sandboxes sometimes leave for kids: parasitic worms. Like giant litter boxes, uncovered sandboxes invite animals—raccoons, dogs, cats—to use them as bathrooms, which essentially turns them into giant parasite Petri dishes. And that’s bad, because even if your kids don’t eat handfuls of sand like mine do, they probably do put their fingers in their mouths an awful lot—and parasites are transmitted by what is not-so-euphemistically called the fecal-oral route, meaning they go from one animal (or kid’s) butt straight to the next kid’s mouth. Bon appétit!
OK, I know you’re rolling your eyes, thinking: But most kids who play in sandboxes don’t get sick. Fair enough. But it’s also possible that kids are getting sick and we just don’t know it. Doctors are not required to notify the government when they diagnose these infections—so no one is closely monitoring them or their epidemiology—and many kids who get parasites probably either never get diagnosed with them, as symptoms can be mild and spontaneously resolve, or their diagnoses are kept quiet. (Are you really going to tell your friends that your kid just got dewormed?) And when little Annie does get parasites, her parents also aren’t going to tie it back to that time three weeks ago when she played in a sandbox. The fact is that a large proportion of Americans—many of them kids—are infected by parasites, and sandboxes are a known hot spot. “There is a real threat,” says Laila Woc-Colburn, an infectious disease specialist at the Baylor College of Medicine in Houston.
Consider what happened when researchers at McGill University tested the surface sand from sandboxes at 10 local day care centers in 1991. Two of the sandboxes, they discovered, were contaminated with eggs of a parasite called Toxocara. Once a child eats them, the eggs hatch in his or her body into larvae, which can burrow into the liver, lungs, central nervous system, or eyes. Sometimes the infection is asymptomatic, but when it’s not and is not properly diagnosed and treated, it can cause liver damage, lung damage, or blindness. (An earlier 1979 study found that a whopping 39 percent of residential sandboxes in Kansas contained Toxocara eggs. Perhaps unsurprisingly, research suggests that 1 out of every 7 Americans over the age of 6 has been infected with this parasite.)
The McGill study also reported that one of the sandboxes with Toxocara eggs was co-contaminated with the eggs of Ascaris, a parasitic worm that can, occasionally, cause intestinal blockage and stunted growth. Another parasite kids can get from sandboxes is Toxoplasma gondii, which is spread by cats and believed to chronically infect more than 1 out of every 6 Americans. In one study, researchers in Japan spied on three urban sandboxes at night using camcorders and found that over the course of five months, cats pooped in the boxes 961 times, and dogs pooped in them 11 times. They calculated that one of the sandboxes contained more than 1.5 million viable Toxoplasma eggs per square foot of sand, yet children need only ingest a single egg to get sick.
Although Toxoplasma infections are typically mild—some people get flu-like symptoms, while others feel fine, though most will harbor the parasite for the rest of their lives—individuals with compromised immune systems can fall very ill, and when women become infected during pregnancy, their babies can develop brain or vision damage or become sick later in life. (Some research also suggests that the parasite can affect behavior and personality. So the next time an aggressive driver cuts you off, calm yourself with the thought that he might be infested.)
Let’s also not forget pinworms, the tiny little worms that live in your intestines, scurry down to your anus while you sleep, and lay their eggs there every night. Nearly half of all American kids are believed to have pinworms at any given time (and when they do, their parents usually have them too), but they’re tough to diagnose: You basically have to set an alarm for a few hours after you go to sleep and then inspect your anus for crawling worms. (No, I’m not kidding.) As Austin, Texas-based pediatrician Ari Brown wrote in her best-selling book Toddler 411, sandboxes are an excellent place for kids to catch pinworms, because pinworms cause kids’ butts to itch; then they scratch their butts, getting pinworm eggs on their fingers; then they build sandcastles studded with worm eggs.
I’ve left my favorite (as in: most absolutely terrifying) sandbox parasite for last. It’s called Baylisascaris procyonis, and it is a roundworm that typically infects raccoons.
As many as 4 out of 5 raccoons carry this parasite, and infected coons typically poop out thousands, if not millions, of eggs a day—perhaps right on your lawn. In a 2009 study, researchers found raccoon poop in more than half of the suburban Chicago backyards they sampled. Once there, the parasite’s eggs are virtually indestructible, except with exposure to very high heat. One scientist who has studied them recommends using an acetylene torch to incinerate the bastards.
Human infections with Baylisascaris seem to be very, very rare, although no one really knows why, considering everything I wrote above. But thank goodness, because the parasites are extremely dangerous. “If eggs are accidentally ingested by a human,” a recent clinical report explained, “larval infection can lead to devastating neurological disease and death.” One-third of cases are fatal. In 2009, two kids from Brooklyn caught it; one developed permanent brain damage, and the other went blind in one eye. Another child fell ill with it in Canada in 2009, presumably after—you guessed it!—playing in a sandbox. He was lucky because he was diagnosed and treated quickly, but the infection nevertheless robbed him of the ability to speak, gave him a seizure disorder, and damaged his eyesight.
So, yes, sandboxes are gross and can be dangerous. This is not to say that you should never let your kids play in them, because the danger is remote—they only rarely cause serious illness (my daughter’s sandy snack seems to have done her no harm, although I haven’t had her tested). If you own your own sandbox, though, consider covering it at night to keep out animals. If you have dogs or cats, make sure they are regularly checked for worms, and keep them out of the sandbox so they never wonder whether it might work well as a toilet. If you suspect that raccoons are pooping on your lawn, check out this Centers for Disease Control and Prevention guide to cleaning up their hazardous excrement.
As for public sandboxes: It kind of goes without saying, but if they smell bad, stay away. Also, (try to) keep your kids from putting their hands (or all the sand) in their mouths when they play, and make them wash their hands afterward. (Hand sanitizer won’t kill worm eggs, Woc-Colburn says, so best to do it the old-fashioned way.) Would it be crazy to steer your kids away from public, always-uncovered sandboxes just in case? No, particularly if your kids have other sources for creative hands-on play. Brown, for one, has advised parents against them. And if your sandbox-frequenting kid does get really sick—symptoms of parasitic infections vary but can include fever, coughs, stomach pain, eye pain, or seizures—of course, take him to the pediatrician, and mention his sandbox use and any other relevant info, such as that you suspect your cat poops in it. Chances are high that your kid is never going to get really sick from sand play, but it’s good to know about the risk just in case, even though it means—and for this I apologize—that you will never be able to look at a sandbox the same way again.
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