Even after passing through water, smoke contains high doses of toxic components including carbon monoxide, heavy metals and a number of cancer-causing substances Water filters individual components with efficiencies from 4.2 to 78.6% with an overall average efficiency of 38% [2]
Dozens of countries in Latin America and Asia have already implemented five rounds of pictorial health warnings on packaging over the past decade, but packaging in the US hasnt changed much since 1985
Federal policies making it dangerous for financial institutions to transact with newly legal (at the state level) marijuana dealers also work to keep black markets alive
Codes that appear intentional, not randomly placed
(10 July 2006), "The Association Between Marijuana Smoking and Lung Cancer", Archives of Internal Medicine , 166 (13): 13591367, doi:10.1001/archinte.166.13.1359, PMID 16832000, S2CID 10117687 Chemicals known to the state to cause cancer or reproductive toxicity (PDF), ca.gov, 20 July 2012, archived from the original (PDF) on 20 January 2013, retrieved 8 January 2013 Evidence on the carcinogenicity of marijuana smoke (PDF), Reproductive and Cancer Hazard Assessment Branch Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, archived (PDF) from the original on 24 July 2012, retrieved 23 June 2012 The impact of cannabis on your lungs , British Lung Association, June 2012, archived from the original on 27 September 2013, retrieved 9 January 2013 "Medical consequences of marijuana use: a review of current literature"