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Drug Enforcement Administration


Deanne L. Reuter, Special Agent in Charge

September 10, 2012

Contact: Steve Kotecki

Phone Number: (571) 387-2287

National Jewish Health Study Documents Health Dangers Of Indoor Marijuana Grows

DENVER, CO. - National Jewish Health’s Dr. John Martyny has announced the results of a study designed to determine the health effects from indoor marijuana grow operations. The study was conducted in conjunction with the Colorado Drug Investigators (CDIA), Colorado Association of Chiefs of (CACP), and County Sheriffs of (CSOC). These organizations had a growing concern about the safety of their officers involved in entering and dismantling indoor grow operations. The Colorado Drug Investigators Association secured a federal Justice Assistance (JAG) through Colorado’s Division of Criminal Justice to finance the study, with the chiefs and sheriffs associations helping to provide some additional funding.

Dr. John Martyny, a professor at National Jewish Health, was the primary researcher on this project. Dr. Martyny and his team also partnered with law enforcement in 2002 when they conducted a study regarding the health impact of clandestine methamphetamine labs. This study resulted in greater safety policies for officers entering and dismantling labs. CDIA Vice President Jerry Peters and CDIA Legislative Liaison Jim Gerhardt coordinated the arrangements for Dr. Martyny and his team to examine and study actual indoor marijuana grow operations. Dr. Martyny tested thirty indoor marijuana grows. His research showed that, in residential and commercial structures, it was difficult to control chemical contamination from pesticides and fertilizers. The study also showed that plant irrigation resulted in increased moisture that could damage building material, result in excessive mold growth, and pose a risk of fire and electrocution. The study shows that highly-elevated airborne levels of mold spores within these structures subjected occupants, emergency personnel and other individuals to significant potential health hazards. Potential health effects include hypersensitivity pneumonitis, allergic rhinitis, asthma and other respiratory diseases. Another concern was elevated carbon dioxide levels which, if generated using fossil fuel combustion, can result in the production of carbon monoxide resulting in significant health effects, or death, to exposed individuals.

Dr. Martyny’s study shows that the greatest risk is to individuals residing in the residence. However, others may be impacted as well, particularly in multi-family buildings which may allow chemicals used and mold spores to be introduced into ventilation systems, exposing other residents. Exposure to children living in these operations also may result in illness, injury or death to an innocent child. Fires may cause damage not only to the indoor grow but also surrounding houses. Lastly, Dr. Martyny cites that, since these operations may go undetected, an unsuspecting family buying the residence at a later date may be put at risk of adverse health effects due to residual mold contamination.

Based on the study and its findings, Dr. Martyny believes that the primary exposure present in indoor marijuana grows consists of high levels of mold spores, low-toxicity pesticides and other chemicals, carbon monoxide and electrical hazards. The recommendation for initial responders, such as a SWAT team, includes fire-resistant gear, chemical-resistant gloves, boots, and a water-resistant and disposable respirator. Officers with any kind of immune system deficiencies should avoid entry into an indoor marijuana grow. He recommends that investigators involved in the removal phase wear full-face air-purifying respirators as well as other protective clothing. Dr. Martyny emphasizes that his recommendations are minimum suggestions and that, when in doubt, safety equipment should be upgraded.

A copy of the report may be found on the Association’s website at www.cdiausa.org.


“DEA agents expect to face certain threats in our job, such as potentially violent criminals, guns and drugs. But the unseen dangers in marijuana grow houses that are described in this study pose an equally serious threat to the health and safety of our agents and law enforcement partners.”
Barbra Roach, Special Agent in Charge DEA Denver Field Division

“The results of this study are far reaching not only as evidence of environmental dangers for first responders, but to children and adults living in and adjacent to these contaminated environments.”
Ernie Martinez, President, Colorado Drug Investigators Association

“Sheriffs in Colorado remain alarmed at the intrusion of the marijuana industry into the safety of our communities and of our deputies. This report adds yet more evidence to support those concerns. Expansion of these hazardous conditions that dangerously expose our deputy sheriffs, industry workers, and even unsuspecting home and business owners is contrary to common sense.”
Stan Hilkey, 2012 President, County Sheriffs of (CSOC)

“The Colorado Association of Chiefs of Police thanks the Colorado Drug Investigators Association and National Jewish Health for their work on this important study. The results are significant for not only law enforcement but the general community as well, particularly as the proliferation of indoor marijuana grows continues in our residential neighborhoods. The study will serve as a guide for future strategies concerning this issue.”
Tom Deland, President, Colorado Association of Chiefs of Police

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