When you're under stress, your brain may release its own cannabinoid molecules to calm you, activating the same brain receptors as THC derived from cannabis plants. But the brain activity regulated by these cannabinoid molecules were not well known. A new study in mice has discovered a key emotional brain center, the amygdala, releases cannabinoid molecules under stress that dampen the incoming stress alarm from the hippocampus, a memory and emotion center in the brain. The finding may reveal novel therapeutic targets for the treatment of stress-related disorders.

New research has detected significant levels of metals in the blood and urine among marijuana users, concluding that marijuana may be an important and under-recognized source of lead and cadmium exposure. This is among the first studies to report biomarker metal levels among marijuana users and most likely the largest study to date, that links self-reported marijuana use to internal measures of metal exposure, rather than just looking at metal levels in the cannabis plant. The results are important because marijuana is the third most used drug in the world.

Scientists evaluate how accurate law-enforcement administered field sobriety tests are at measuring cannabis exposure and impairment.

Researchers showed that consuming THC while pregnant could potentially affect development of the fetus and lead to life-long health impacts for offspring.