Study Concerning the Health Impact of Indoor Marijuana Cultivation
National Jewish Health’s Dr. John Martyny today announced the results of a study
today designed to determine the health effects from indoor marijuana grow operations.
The study was conducted in conjunction with the Colorado Drug Investigators Association (CDIA),
Colorado Association of Chiefs of Police (CACP), and County Sheriffs of Colorado (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 Grant (JAG) through Colorado’s Division of Criminal Justice to
finance the study, with the chiefs and sheriffs associations helping to provide some additional
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 shows that, in residential and
commercial structures, it was difficult to control chemical contamination from pesticides and
fertilizers. The study also shows 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 www.cdiausa.org.
“Unlike you may hear some suggest, because this is a constitutional right under Amendment
20, we cannot prohibit growing marijuana in neither private residences nor commercial
buildings, both of which are dangerous. 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
“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
Barbra Roach, Special Agent in Charge DEA- Denver Division