This article is from the archive of our partner National Journal

As legal marijuana proliferates across the country, one consequence appears to be unavoidable: More young children will accidentally be exposed to pot. It's just entropy, a law of nature: If a child can get its hands on something, he or she will eventually.

The journal Clinical Pediatrics recently published a comprehensive study of marijuana exposures of children under the age of 6. Compiling 13 years of data (2000 through 2013) from the National Poison Data System, the researchers found that while these incidents are rare, they are growing quickly. On average, there are 5.90 marijuana exposures per million kids in the age group. But here's the kicker: That rate increased 147.5 percent from 2006 to 2013. Most of that is attributable to states that legalized medical marijuana before 2000. Those areas saw a 609.6 percent percent increase in marijuana exposures; a rate that has accelerated since 2009, the study notes. In a state where medicinal marijuana was legalized before 2000, a child is 2.8 times more likely to be exposed.

Overall, marijuana exposure rates increased for kids under age 6 from 2000 to 2013.

But the states that legalized medicinal marijuana before 2000California, Oregon, Washington, Alaska, and Maine—have seen a much higher increase.

Those rate increases are eye-popping, but consider how infrequent marijuana exposures are compared to household bleach exposures. According to a 2010 report in the journal Pediatrics, the rate of bleach poisonings for kids under the age 5 is around 1.75 per 10,000 (extrapolated out, that's 175 per million). Bleach is in most households. Marijuana isn't. But if marijuana continues to proliferate legally into parents' homes, the exposure rates may keep rising.

The Clinical Pediatrics paper also tracked the medical outcome for the little ones who were exposed to marijuana. In only 1.1 percent of the cases were the effects of the pot exposure major, meaning they were life-threatening or significantly disabling. Forty-seven percent of the cases were minor or moderate in severity. Most often—45.5 percent of the time—the kids experienced drowsiness.

Other notable statistics:

â—† 75 percent of the kids were exposed through ingestion (inhalation accounted for 14.5 percent of cases). Other studies have found that marijuana-laced candies and chocolates are of particular concern for kids.

â—† Three-quarters of the kids exposed were under age 3. The mean age of kids exposed was 1.81 years.

â—† Between 2000 and 2013, 1,969 marijuana exposures occurred in the age range (50.7 percent of the exposed kids were males).

â—† In 31.7 percent of the cases, the children were not treated at a health care facility.

"Legalizing the medical or recreational use of marijuana may have economic or other benefits, but lawmakers also need to be aware of the potential hazard associated with unintentional exposure of young children," the study concludes. "It is imperative that commercially available marijuana products be sold in opaque, child-resistant packaging to mitigate the risk of child exposure."

Colorado recently enacted stricter packaging regulations. And there's reason to believe that can work to keep kids' hands off pot. In 1970, Congress passed the The Poison Prevention Packaging Act of 1970, requiring child-resistant packaging for many household drugs and cleaners. Those efforts, combined with increased education and awareness, led to a marked drop in children's exposure to household cleaners, Pediatrics notes. From 1990 to 2006, the number of those cases decreased nationwide by 46.0 percent.

But the states that legalized medicinal marijuana before 2000"”California, Oregon, Washington, Alaska, and Maine"”have seen a much higher increase.

Those rate increases are eye-popping, but consider how infrequent marijuana exposures are compared to household bleach exposures. According to a 2010 report in the journal Pediatrics, the rate of bleach poisonings for kids under the age 5 is around 1.75 per 10,000 (extrapolated out, that's 175 per million). Bleach is in most households. Marijuana isn't. But if marijuana continues to proliferate legally into parents' homes, the exposure rates may keep rising.

The Clinical Pediatrics paper also tracked the medical outcome for the little ones who were exposed to marijuana. In only 1.1 percent of the cases were the effects of the pot exposure major, meaning they were life-threatening or significantly disabling. Forty-seven percent of the cases were minor or moderate in severity. Most often—45.5 percent of the time—the kids experienced drowsiness.

Other notable statistics:

â—† 75 percent of the kids were exposed through ingestion (inhalation accounted for 14.5 percent of cases). Other studies have found that marijuana-laced candies and chocolates are of particular concern for kids.

â—† Three-quarters of the kids exposed were under age 3. The mean age of kids exposed was 1.81 years.

â—† Between 2000 and 2013, 1,969 marijuana exposures occurred in the age range (50.7 percent of the exposed kids were males).

â—† In 31.7 percent of the cases, the children were not treated at a health care facility.

"Legalizing the medical or recreational use of marijuana may have economic or other benefits, but lawmakers also need to be aware of the potential hazard associated with unintentional exposure of young children," the study concludes. "It is imperative that commercially available marijuana products be sold in opaque, child-resistant packaging to mitigate the risk of child exposure."

Colorado recently enacted stricter packaging regulations. And there's reason to believe that can work to keep kids' hands off pot. In 1970, Congress passed the The Poison Prevention Packaging Act of 1970, requiring child-resistant packaging for many household drugs and cleaners. Those efforts, combined with increased education and awareness, led to a marked drop in children's exposure to household cleaners, Pediatrics notes. From 1990 to 2006, the number of those cases decreased nationwide by 46.0 percent.

This article is from the archive of our partner National Journal.