Cannabis Smoke and Children
1,375%increase in child cannabis poisonings (2017–2021)
3 yrsmedian age of affected children
2×faster breathing rate in toddlers vs adults
Two separate problems
Children face two distinct categories of cannabis risk, and it helps to be clear about both.
The first is secondhand smoke — breathing in the smoke from cannabis being used nearby. This is the core focus of this site, and the section below covers what makes children especially vulnerable to it.
The second is accidental ingestion — young children eating cannabis edibles that look like candy. This is a different mechanism with different consequences, but it is rising fast enough to warrant serious attention.
Secondhand smoke and children
Why children absorb more
Children's bodies are not smaller versions of adult bodies. Their developing physiology responds to cannabis smoke exposure differently in several specific ways:
- They breathe faster. Young children breathe at roughly twice the adult rate — about 20–40 breaths per minute in toddlers versus 12–20 in adults. In the same environment, they take in proportionally more particles per unit of body weight.
- Their metabolism is unpredictable. Young children may metabolize THC unpredictably due to immature hepatic enzyme systems. Case reports have documented THC half-lives exceeding 50 hours in infants.
- Their developing brains are more vulnerable. The endocannabinoid system plays a critical role in ongoing neurodevelopmental processes including synaptic pruning and myelination. THC exposure during this window can disrupt these processes.
- They cannot leave. Infants in strollers, toddlers in car seats, and children in apartments cannot remove themselves from a smoky environment.
Child on a playground or in a park
Research has confirmed that secondhand cannabis smoke exposure in young children results in measurable THC absorption. A study at Mount Sinai found detectable THC metabolites in over 20% of children aged 0–3 tested during routine hospital visits. Dr. Karen Wilson, lead researcher, stated: "Secondhand marijuana smoke does get into the lungs and little bodies of young children."
This is not theoretical. These are measurable concentrations of THC in children whose parents or caregivers smoke nearby.
Real case
THC found in 1 in 5 young children at a New York hospital
Researchers at Kravis Children's Hospital at Mount Sinai tested children aged 0–3 during well-child visits and inpatient stays between 2017 and 2018. THC metabolites were detectable in 20.8% of samples. None of these children were given cannabis intentionally — the exposure came from secondhand smoke in their living environments.
Source: Pediatric Research, 2021
Accidental ingestion — a separate but growing crisis
Since legalization, a different kind of exposure has surged: young children eating cannabis edibles that are packaged to look like ordinary candy.
Nationally, cannabis poisoning cases in children under 6 increased by 1,375% between 2017 and 2021. The median patient age was 3 years old. Cannabis-infused chocolates and gummies accounted for nearly three-quarters of ingestions, with many products sold in packaging that mimics popular kids' brands like Sour Patch Kids, Nerds Rope, and Skittles.
Unintentional cannabis exposures in children under 6
National poison center reports, indexed to 2017 baseline. A 1,375% increase over four years.
2017
Baseline baseline
2018
2.1× baseline
2019
3.9× baseline
2020
6.8× baseline
2021
13.75× baseline
Source: Goldberger et al., Pediatrics 2023Children ≤5 years old · Edible ingestions · National data
The FDA received over 125 adverse event reports related to children consuming THC edibles between January 2021 and May 2022 alone. Symptoms included hallucinations, increased heart rate, vomiting, and respiratory depression. Many required hospital admission.
Real case
FDA warns about copycat cannabis edibles targeting children
Between 2021 and 2022, the FDA received over 125 adverse event reports of children and adults accidentally consuming THC edibles packaged as popular candy brands. Ten reports specifically identified copycat products mimicking Cocoa Pebbles, Gushers, Nerds Rope, Skittles, and Sour Patch Kids. The FTC subsequently took enforcement action against sellers for deceptive packaging.
Source: FDA Safety Alert, 2022
The developing brain
The human brain is not fully developed until around age 25. During childhood and adolescence, the brain is actively building and refining its connections — and the endocannabinoid system, which THC directly disrupts, plays a central role in that process.
How THC affects the brain's signaling system
The brain has its own cannabis-like system. THC hijacks it.
Your brain's own system
Your brain naturally produces its own cannabis-like molecules that help regulate mood, memory, and stress. They work in small amounts and the brain controls exactly how much is released.
This system helps maintain balance. It is not designed to handle the signal strength of high-potency THC.
CB1 receptor expression in the prefrontal cortex peaks during early adolescence. The endocannabinoid system during this period is helping direct how the brain is wired: which connections get strengthened, which get pruned, and how different brain regions balance each other.
A large longitudinal study tracking 799 adolescents found that cannabis use was associated with accelerated thinning of the prefrontal cortex, observable on MRI scans. The spatial pattern of this thinning matched the known distribution of CB1 receptors — strongly suggesting the effect is directly neurobiological rather than coincidental.
Other findings from longitudinal research:
- Persistent adolescent-onset cannabis use is associated with cognitive decline — including effects on memory and processing speed — that persists into adulthood.
- The lifetime risk of developing cannabis use disorder is approximately double for people who start using in adolescence compared to adult-onset users.
- Daily high-potency use before age 18 is associated with substantially elevated risk of psychotic disorder.
The consent problem
Children near cannabis smoke are not making a choice. They cannot recognize the air is harmful. They cannot ask an adult to stop. They cannot move themselves to a different location.
Empty playground bench, clean and quiet
This is the part of the conversation that tends to get skipped when cannabis is discussed as an individual rights issue. Personal choice has a radius. In the case of a child who lives with a smoking parent, that radius is their entire childhood.
Back to home
Reviewed July 1, 2026 · v0.3 · suggest a correction