Childhood exposure to marijuana – What you should know

The recent decriminalization of medical marijuana in several states in the US comes as good news to those who depend on the drug for treatment of chronic disease. But there are also drawbacks to these changes in legislation; in particular, more children are being accidentally exposed to marijuana smoke and marijuana in food. What should parents and health care providers know about the health effects of marijuana, and what steps should we take to keep our children safe?

What is the difference between medical and recreational marijuana?
In essence there is no difference between marijuana sold for medical and recreational use. Recreational marijuana sellers use many of the same growers and kinds of marijuana as proprietors of medical marijuana. Medicinal marijuana has been processed to have therapeutic effects, so it may have lower levels of tetrahydrocannabinal (THC) and higher levels of other substances believed to help improve certain medical conditions.  Types of marijuana that are processed for recreational use may have more effects on mood and thinking.

How can children be exposed to marijuana?
Children can be exposed to marijuana either by breathing in secondhand smoke or eating foods containing marijuana. During the use of marijuana cigarettes, secondhand smoke is generated from the end of the joint (85%) and by the exhalation of the smoker (15%). Any children nearby are exposed to this secondhand smoke just by natural breathing. There are reports of marijuana secondhand smoke exposure severe enough to require hospital admission.

Smoke from marijuana contains a complex chemical mixture, which may be dangerous. A study in 2008 showed that marijuana smoke contains many of the same cancer-causing chemicals as tobacco smoke. Certain chemicals, including cyanide and ammonia, are significantly higher in marijuana smoke compared to cigarette smoke. Parents should take the same caution with marijuana smoke as they do with tobacco smoke.

Most children who require hospital treatment from marijuana exposure have eaten food products containing marijuana. Many new marijuana products on the market are tempting to children because they look like bakery products and candies. These products often contain more THC than marijuana smoke. All marijuana products should be stored where children cannot find them.

What are the health effects of marijuana exposure in children?
When children eat food containing marijuana they can have extreme sleepiness or lethargy. Children can also experience the same effects as adults including blood shot eyes, increased appetite, dry mouth, anxiety, and impaired motor coordination. If they inhale marijuana smoke they can those symptoms plus lung irritation and asthma attacks. Symptoms can last up to 24 hours after exposure. While no childhood deaths from marijuana poisoning have been reported, contact your local poison center if you think your child has eaten or inhaled marijuana.

What are potential long-term health effects of marijuana smoke exposure?
Many of the long-term health effects of exposure to marijuana smoke are still being studied but may include cough and respiratory infections. There is also an increased risk of heart attack, stroke, decreased fertility, and alterations in memory, attention, and learning. There is no evidence yet that exposure to marijuana smoke can cause cancer, although marijuana smoke contains cancer-causing chemicals.

Can children get a “contact high”?
When marijuana is burned, it triggers a chemical reaction that produces THC. While a large portion of the THC is delivered directly to the smoker’s lungs, a smaller but still significant amount is released into the air. The level of exposure to THC in the air is higher in small, enclosed areas or areas with poor ventilation. A study conducted in 1983 showed that inhalation of secondhand marijuana smoke can result in detectable levels of THC in the blood and urine. The marijuana used in this study contained 2.8% THC, but the average THC in today’s marijuana is 18%. Vaporizing marijuana plant oils can result in very high THC proportions (50%). Therefore, children exposed to secondhand marijuana smoke are probably exposed to enough THC to have positive levels in their blood and urine.

Is smoking marijuana dangerous during pregnancy?
It can be. A study published in 1994 showed that children aged 3 and older whose mothers smoked marijuana during pregnancy had a decrease in attention span, brain function, and memory. A similar study in 2004 showed that children born to mothers who smoked marijuana in the first and third trimesters of pregnancy had higher levels of anxiety and depression.

How can I protect my child from the health hazards of marijuana?

• Keep your home free of marijuana smoke.

• Do not smoke marijuana in the car or other small, enclosed places.

• Keep marijuana-containing foods or drinks out of reach of children.

• Contact your local poison center if you think your child may have eaten or inhaled marijuana.

This post was written by Kristina Dakis, Medical student at the University of Illinois at Chicago College of Medicine. Edited by Susan Buchanan, MD.

References:
Anderson M, Wang GS, Keteles K, Van Dyke M. Pediatric exposure to marijuana. PEHSU Network National Conversation. Apr. 2014.

Colorado Marijuana. Colorado Department of Public Health & Environment – The State of Colorado, n.d. Web. 10 Aug. 2014. https://sites.google.com/a/state.co.us/marijuana/

Wang GS, Roosevelt G, Heard K. Pediatric marijuana exposures in a medical marijuana state. JAMA Pediatr. 2013 Jul;167(7):630-3.

Wang GS, Narang SK, Wells K, Chuang R. A case series of marijuana exposures in pediatric patients less than 5 years of age. Child Abuse Negl. 2011 Jul;35(7):563-5.