Methamphetamine-contaminated residences in the United States: Assessment of the environmental health significance of thirdhand exposure

Methamphetamine (meth) use in the United States has been a significant problem since the 1960s. Beyond impacts to the users, two additional consequences of the meth problem are ongoing exposure to non-users in contaminated homes and the subsequent remediation costs. This study provides estimates of the number of contaminated properties, the number of exposed non-users, and the costs associated with remediation in the U.S., nationally and by state. Surveys of the frequency or incidence of residential contamination are difficult to perform and are scarce. A survey found that ∼3.5% of housing units (HUs) in the Boulder, Colorado, area were contaminated as of 2018. Estimates of contamination rates from meth smoking, manufacture, and decontamination provided the net rate of HUs affected. The rate equation was integrated to estimate the number of contaminated HUs, the number of people living in contaminated HUs, and the potential remediation costs from 1990 to 2022. Currently, more than 5.5 million (4%) of U.S. HUs are estimated to be contaminated, and the estimated annual cost to remediate all contaminated HUs is $12 billion; this is in addition to the $240 billion required to remediate the backlog of contaminated HUs. Thirteen million people are estimated to be currently living in contaminated HUs. These estimates indicate that meth-contaminated housing is an environmental health and economic issue in the U.S. that has been previously under-recognized. Additional studies are needed on the incidence of contaminated HUs, their health effects, fate and transport mechanisms, and remediation methods.