Mount Sinai Researchers Find Signs of Exposure Secondhand Marijuana Smoke Exposure in Children
Children exposed to secondhand marijuana smoke show measurable amounts of the drug in their bodies, a researcher at the Icahn School of Medicine at Mount Sinai has found. The study was published in the journal Pediatric Research.
The study found that when young children are exposed to secondhand marijuana smoke, measurable amounts of primary metabolite of the active component in psychoactive chemical Δ9-tetrahydrocannabinol (THC) appears in samples of their urine. Because earlier analytical methods were developed to measure biomarkers of marijuana in primary users of the drug, a new, more sensitive analytic method was developed and used by the U.S. Centers for Disease Control and Prevention (CDC) to quantify the trace biomarkers resulting from secondhand marijuana smoke exposure.
“This shows that, like tobacco smoke, marijuana smoke is inhaled by children in the presence of adults who are using it,” said Karen Wilson, MD, Debra and Leon Black Division Chief of General Pediatrics, and the Vice-Chair for Clinical and Translational Research for the Department of Pediatrics at the Icahn School of Medicine at Mount Sinai. “In areas where marijuana use is legal, or common, education is needed to counsel parents on the dangers posed to their children by secondhand smoke.”
For the study, urine samples were collected from 43 babies between the ages of one month and two years who were hospitalized in Colorado with bronchiolitis, and their parents were asked to complete a survey about marijuana smoking habits. The samples were analyzed, and levels of biomarkers for a marijuana metabolite (COOH-THC) were recorded. COOH-THC was detectable in 16 percent of the samples, at concentrations between 0.04 and 1.5 nanograms per milliliter of urine – lower than would be seen in a primary user. This percentage was consistent with the number of parents who self-reported marijuana usage in the survey.
“Parent reported screening questions in areas where marijuana is legal is a helpful first step,” said Dr. Wilson. “While we do not know yet whether this exposure poses a health risk to children, this study highlights the urgency of further investigation.”
About the Mount Sinai Health System
Mount Sinai Health System is one of the nation’s leading integrated academic health systems and one of the largest in the New York metropolitan area. Its comprehensive system includes seven hospitals, more than 400 outpatient practices, over 600 research and clinical laboratories, the Icahn School of Medicine at Mount Sinai, the Graduate School of Biomedical Sciences, and the Mount Sinai Phillips School of Nursing. Together, the Health System comprises approximately 48,000 employees, more than 9,000 physicians, and 8,600 nurses.
As a leading learning health system, Mount Sinai combines clinical expertise with scientific discovery to improve patient care while training the next generation of health care and biomedical leaders. The Health System provides care across every stage of life, from prenatal care through geriatrics, while advancing personalized medicine through artificial intelligence, data science, and biomedical research.
Mount Sinai is consistently recognized among the nation’s leading academic health systems for patient care, research, and education. The Mount Sinai Hospital is ranked No. 1 in New York by Newsweek and No. 5 on the magazine’s World’s Best Hospitals list. The Icahn School of Medicine at Mount Sinai ranks No. 11 among U.S. medical schools and No. 1 among freestanding medical schools for National Institutes of Health funding, reflecting the strength of its scientific enterprise and leadership in biomedical research.
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