“When surfaces are contaminated by methamphetamine residues from manufacturing, handling, distribution and/or use, how long do the residues last?” …and if present, do the concentrations of these residues degrade, change, or lessen over time?”

As BioMax Environmental’s Senior Certified Industrial Hygienist (CIH) involved in numerous assessment and cleanups of properties contaminated with illicit drug residues, I have been asked this important question many times.    Although peer-reviewed research is needed to answer this question.  None is known to exists at this time. However, my experience in a real-world case involving the assessment results in an undisturbed property over 8 years, provides a snapshot of evidence and some insight into answering these questions.

Background to the Problem:  There may be many types of methamphetamine-related contamination compounds found present on surfaces located within properties contaminated by illicit methamphetamine manufacturing, handling, and use.  This is known to vary widely and depends on the specific manufacturing methods employed, the precursor chemicals used, whether the illicit products were being handled and packaged, and if the drug products were being used recreationally at the site.  According to the US Drug Enforcement Agency (DEA), many uncontrolled contaminated drug manufacturing and handling sites which are discovered each year in the US by law enforcement, first responders, or property owners.  Toxic contamination frequently remains at these clandestine sites and will include a number of toxic chemical residues on surfaces generated by a combination of the factors noted above.  In all cases, the resultant surface residues that remain on surfaces that have been involved with these illegal manufacturing, handling and distribution activities will include pervasive chemical contamination.  These contaminants are able to be sampled from surfaces and then identified and measured (through laboratory analysis) to identify the target “indicator” chemical compound, methamphetamine. Airborne methamphetamine contamination resulting from manufacturing, conversion, and purification activities produce residues that transfer through the air and settle on surfaces of residences and properties where these illicit manufacturing processes and activities have occurred.

Residue contamination also occurs at properties and residences where methamphetamine containing products are handled, weighed, packaged, and distributed.  Forms of finished products for distribution and use include methamphetamine crystals, powders, and liquids.  Other common sources of methamphetamine residue contamination of interior surfaces will occur during the process of methamphetamine use where airborne aerosols are generated by users during free-basing or “smoking” of meth.  During smoking, the meth is converted from a solid powder or crystal into a superheated liquid vapor within a “meth pipe”, a spoon, or piece of foil.  The user generally heats the meth with a flame (or heating element) and inhales the methamphetamine vapors and tiny semi-liquid droplets (known as aerosols) that are generated directly into his/her lungs.  These tiny airborne semi-liquid “smoke-like” particles are known to be   “sticky” as they recondense and readily travel and distribute throughout the area and commonly settle and adhere onto exposed surfaces.  This results in properties and residences which are considered to be uncontrolled sites…. Meaning they will contain concentrations of meth residues present on virtually all exposed surfaces.

The question as to how long these residues will remain on surfaces (once they adhere and/or settle) is a very important topic when it comes to the cleanup of sites and safely re-occupied by residence following discovery and cleanup.  This is important because it can sometimes be many years after discovery by law enforcement or when the owners (or occupants) find out that their home was contaminated by previous manufacturing or other illicit occupant activity.  In a number of cases I have managed, repainting of interior walls had occurred by property owners and tenants unaware of the presence of methamphetamine contamination but still resulted in elevated levels on these newly painted surfaces.  Research studies have shown that painting over contaminated surfaces offers limited protection and does not eliminate the presence and/or bio-availability of methamphetamine exposure to persons who have contact with these surfaces where methamphetamine contamination was covered with paint.

In answering the question of methamphetamine contaminant persistence over time, I had the opportunity to manage a project where a contaminated residence impacted by methamphetamine laboratory-related activities had been discovered by law enforcement within a vacation-type residence in a small town located in the Sierra Nevada foothills of California.  The clandestine site was discovered by local law enforcement and subsequently red-tagged by the local health department in accordance with state regulations at that time.  Entry access and occupancy not allowed, pending site assessment and cleanup.  A third-party consultant was hired to perform a preliminary sampling assessment of the interior of the residence and surface residue levels of methamphetamine were identified.  Findings included concentrations of surface residues ranging from 10 to 100 micrograms per 100 cm2 present on accessible surfaces sampled within the residence.  These levels exceeded the current California cleanup criteria standard at the time and required cleanup under the authority of the local health department.

The property remained red-tagged and was placed in a secured state with windows and doors securely boarded to preclude entry for a period of 8 years due to lack of funds to perform the required cleanup.  Following this original assessment, 8 years later I was contacted to perform a follow-up assessment.  Results of this follow-up assessment revealed that the levels of meth contamination on interior surfaces had not changed and indicated similar levels on surfaces within the residence after 8 years. At the time of our follow-up assessment, all entry points into the residence were noted in a secure condition where no evidence of previous entry and/or access into the site had occurred.  This case study provided evidence that methamphetamine contaminant residues on surfaces within a secured property remained unchanged after an 8 year period.

This case study served as unique opportunity in a controlled real-world environment to compare residue levels on undisturbed surfaces over an extended period of time.  What the findings showed was that methamphetamine residues do not degrade within a residential property over time if left undisturbed.

About the Author… Mr. Michael A. Polkabla, CIH, REA is BioMax Environmental, Inc’s Senior Certified Industrial Hygienist and Principal and has over 30-years of experience in the fields of illicit drug residue assessment and cleanup throughout California and the western United States.  Mr. Polkabla has worked with the California Department of Toxics Substances Control (DTSC) and other regulatory agencies in the development and implementation and enforcement of current methamphetamine and fentanyl assessment and cleanup regulations, standards, and guidelines within California.