Acute effects may include anxiety and panic, impaired attention, and memory (while intoxicated), an increased risk of psychotic symptoms, and possibly an increased risk of accidents if a person drives a motor vehicle while intoxicated. Short-term cannabis intoxication can hinder the mental processes of organizing and collecting thoughts. This condition is known as temporal disintegration. Psychotic episodes are well-documented and typically resolve within minutes or hours. There have been few reports of symptoms lasting longer.
Since Cannabis smoke contains many of the same components as tobacco smoke, there are valid concerns about the adverse pulmonary effects of inhaled Cannabis. A longitudinal study in a noncancer population evaluated repeated measurements of pulmonary function over 20 years in 5,115 men and women whose smoking histories were known. While tobacco exposure was associated with decreased pulmonary function, the investigators concluded that occasional and low-cumulative Cannabis use was not associated with adverse effects on pulmonary function (forced expiratory volume in the first second of expiration [FEV1] and forced vital capacity [FVC]).
Cannabis is believed to be an aggravating factor in rare cases of arteritis, a serious condition that in some cases leads to amputation. Because 97% of case-reports also smoked tobacco, a formal association with cannabis could not be made. If cannabis arteritis turns out to be a distinct clinical entity, it might be the consequence of vasoconstrictor activity observed from delta-8-THC and delta-9-THC. Other serious cardiovascular events including myocardial infarction, stroke, sudden cardiac death, and cardiomyopathy have been reported to be temporally associated with cannabis use. Research in these events is complicated because cannabis is often used in conjunction with tobacco, and drugs such as alcohol and cocaine. These putative effects can be taken in context of a wide range of cardiovascular phenomena regulated by the endocannabinoid system and an overall role of cannabis in causing decreased peripheral resistance and increased cardiac output, which potentially could pose a threat to those with cardiovascular disease. There is some evidence from case reports that cannabis use may provoke fatal cardiovascular events in young people who have not been diagnosed with cardiovascular disease. Smoking cannabis has also been shown to increase the risk of myocardial infarction by 4.8 times for the 60 minutes after consumption.
Senate Majority Leader Mitch McConnell (R-KY) introduced new legislation in April that would declassify non-psychoactive cannabis varieties -- more commonly referred to as hemp -- from the Controlled Substances Act. The legislative proposal comes as part of McConnell's Hemp Farming Act of 2018, which would remove barriers placed on banking access and water rights in addition to legalizing the crop.
A chief argument that has been advanced in favor of developing hemp as a paper and pulp source has been that as a non-wood or tree-free fiber source, it can reduce harvesting of primary forests and the threat to associated biodiversity. It has been claimed that hemp produces three to four times as much useable fiber per hectare per annum as forests. However, Wong (1998) notes evidence that in the southern US hemp would produce only twice as much pulp as does a pine plantation (but see discussion below on suitability of hemp as a potential lumber substitute in areas lacking trees).
Industrial hemp is a versatile agricultural plant which could one day be a valuable crop option for Pennsylvania farmers. The Commonwealth of Pennsylvania has taken some important steps toward making that a reality. Following Governor Wolf’s signing of the Industrial Hemp Research Act, Number 92 in 2016, the Pennsylvania Department of Agriculture’s Industrial Hemp Research Pilot Program started issuing permits for research & growth of industrial hemp in 2017. Pennsylvania’s industrial hemp legislation was sparked by the passage of the 2014 Farm Bill, which gave federal permission for institutions of higher education or state Departments of Agriculture to research the cultivation and marketing of industrial hemp. As part of Pennsylvania’s Research Pilot Program, industrial hemp was legally grown in the Commonwealth after an 80 years hiatus. The Department of Agriculture has issued 35 research permits in the last two years to institutions of higher education and to farmers, business or individuals in contract with the Department to participate in the research of industrial hemp cultivation and marketing in Pennsylvania. In 2018, 35 research permits were issued to researchers, who cultivated industrial hemp in 25 Pennsylvania counties.
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