There were 985 calls to U.S. poison centers for unintentional marijuana exposure in children ages 9 and younger between 2005 and 2011, according to an analysis of data from the National Poison Data System (NPDS). While this number is relatively low, the rate of calls in states that had passed legislation legalizing marijuana use for recreational or medicinal purposes before 2005 more than tripled over this period, increasing from 3.9 calls per 100,000 population in 2005 to 14.8 per 100,000 in 2011.
The call rate in transitional states—those that had enacted legislation between 2005 and 2011—also increased over the period, from 5.2 per 100,000 to 8.7 per 100,000. In contrast, states that had not passed marijuana decriminalization laws as of December 31, 2011 (nonlegal states) showed no change in the rate of poison center calls for unintentional pediatric exposure to marijuana (see figure below). Furthermore, exposures in decriminalized states were more likely than those in nonlegal states to require health care evaluation, to have moderate to major clinical effects, and to require critical care admissions (data not shown). The authors conclude that “as more states pass legislation to decriminalize medical and recreational marijuana, we expect the rate of marijuana exposures in young children to continue to increase” (p. 4) and suggest that “state lawmakers should consider requirements, such as child-resistant packaging, warning labels, and public education, when drafting marijuana legislation to minimize the effect on children” (p. 5).