Bad grades due to negative affects on paying attention learning, and memory.
Leading students to drop out.
Long and short term positive effects
Decreased anxiety, decreased depression symptoms, reduced nausea and vomiting, and pain relief all over the body.
Long and short term negative effects
Increased heart rate
heart disease
Heart attack
Chronic cough, respiratory infections, pneumonia, memory problems, trouble for the developing brain, red eyes, burning mouth, lung irritation, damaged blood vessels, paranoia, and hallucinations.
Heavy marijuana users were less likely to complete college and had annual household incomes of less than $30,000. The majority of those who used marijuana extensively reported negative effects in all of these aspects of their lives, including brain function, job accomplishments, social lives, and physical and mental health.
Studies have also found associations between marijuana usage and negative workplace effects, such as an increased risk of injuries or incidents. Employees who tested positive for marijuana on an employment training urine drug test had 55 percent more workplace incidents, 85 percent more injuries, and 75 percent more absences than those who tested negative for marijuana use, according to a study of postal workers.
Drought is likely to increase in many parts of Canada, including the southern interior of British Columbia and the Prairie provinces. Marijuana farms in these areas would place even more pressure on local water supplies. Marijuana farms could use all of the water that would otherwise be used to keep local streams and rivers flowing during the dry season.
Cannabis plants also contain volatile organic compounds which have been found in the soil near grow-ops and can pollute the environment.
According to a recent study, more than 85% of Pacific fishers near marijuana grow-ops in the Sierra Nevada range were poisoned, accounting for around 10% of all deaths of the endangered species.
Poisoning from marijuana farming has also killed
Mule Deer
Grey Foxes
Coyotes
Northern Spotted Owls
Ravens
Deforestation
Forest Fragmentation