Methamphetamine contamination of residential properties remains a serious public health concern for members of the public. External stakeholders including Environmental Health Officers (EHOs) and testing and remediation technicians are engaged on investigating whether contamination has occurred from manufacturing or smoking processes. More specifically, local council EHOs are responsible for managing clandestine drug laboratories when notified by police and also for responding to public enquiries. However, the full scope of these contaminated properties is not seen by any single stakeholder, making it very challenging to quantify these situations. To evaluate the prevalence of methamphetamine related enquiries from the general public to EHOs, this study surveyed and interviewed officers from around Australia. It was found that public enquiries were infrequent with only 6% of respondents having received enquiries in the last month, which indicates that people are seeking information from other sources. Interestingly, there were case study scenarios that also mentioned issues with awareness and the flow of information. Concerns regarding difficult cases, police notifications, and site visits were also highlighted. The results of this study provide a benchmark of how methamphetamine related cases are managed and highlight the need for trustworthy information that is available to EHOs, governments, industry members, and the public in a unified location.

In New Zealand, many concerns have been raised over the presence of methamphetamine contamination in households, especially when its provenance is unknown. Previous research found that contamination levels on household surfaces were higher after the premises had been used as a clandestine laboratory. It is believed that the levels of contamination produced from smoking methamphetamine are much less than those produced through manufacture. This study\'s aim was to determine the amount of methamphetamine contamination produced, after simulated smoking, on a range of common, smooth surface types. Accumulation over time was also investigated. The experiment, comprising four simulated smoking events (referred to as \'smokes\') of 0.2 g followed by a fifth simulated smoking event of 1.2 g (a cumulative total of 2 g) of methamphetamine hydrochloride, was carried out in a shipping container. Subsequent swabs were taken from squares of 100 cm2, following the NIOSH 9111 method. Results were quantified using LC-MS/MS. The methamphetamine concentrations measured gave a range from an overall mean of 0.91 µg/100 cm2 after the first smoke and 15.9 µg/100 cm2 after the final smoke. A rate of accumulation for each surface type was established, as well as an order of surfaces showing the most to least observed contamination. A significant reduction in the level of contamination was observed over a short period of time, although a clear rate was not established. Finally, a relationship between the recovered amounts of methamphetamine and amphetamine produced through the pyrolysis (smoking) process was also determined.

To better protect public health from third-hand exposure to methamphetamine, it is important to understand the techniques and current practices used within the methamphetamine testing and decontamination industry in Australia. A survey was conducted focusing on business owners that advertised testing and/or remediation services online. They were also invited to participate in a follow-up phone interview upon completion. The survey demonstrated that testing and decontamination methods were highly varied, which was expected for an industry with no regulation. Most companies offered methamphetamine testing and remediation which could be a conflict of interest. Participants also shared personal experiences, including the conduct of other industry members, demonstrating both poor practice and/or the competitive nature of the business. Participating business owners were following Australian guidelines to the best of their ability, and many are advocates for regulation to be implemented within the industry. This would address the inconsistencies between companies and establish trust for industry members and the public. It would also provide significant public health protection, which is currently lacking. A more consistent approach to the testing and remediation of methamphetamine contamination, aided by regulation, would address the significant risk to public health caused by third-hand exposure to methamphetamine.

In New Zealand, concerns have been raised over the presence of methamphetamine contamination in households, especially when the activity causing the contamination is unknown. The cause of contamination is also a contentious issue in clandestine laboratory cases concerning charges in relation to \"Use of Premises\" (Section 12: Misuse of Drugs Act 1975, New Zealand). Regardless of the cause, other than scientific opinion, there is currently no analytical technique that can satisfactorily address the provenance of methamphetamine residues. For several years, approximate methamphetamine contamination levels have been collected from suspected clandestine laboratories in New Zealand, where methamphetamine is believed to have been manufactured. This study used this data and compared it to similar data from properties where the drug is suspected to have been used (smoked) to model likelihood ratios (LR). It is well documented that the LR forms the backbone to a Bayesian method of interpreting forensic evidence. As such, this data has the potential to underpin a novel Bayesian approach in the evaluation of clandestine laboratory evidence.

In November 2016, whilst in draft, the New Zealand Standard (NZS8510:2017) for the \"Testing and Decontamination of Methamphetamine-Contaminated Properties\" considered two acceptable post-decontamination re-occupancy methamphetamine levels; 1.5μg/100cm2 if the contamination was caused by smoking methamphetamine and 0.5μg/100cm2 if the contamination was caused by the manufacture of methamphetamine. In response to this, research carried out at this laboratory included the analysis of data obtained from over a thousand pre-decontamination property test reports with the aim of understanding the variation in the levels of contamination, that could be expected, among the wider New Zealand (contaminated) housing stock. The vast majority of the reports originated from public sector agency properties where methamphetamine was suspected to have been used. Although it could not be ruled-out, none of the properties had been associated with any suspicion of drug production. Thus, a further intention of the study was to assess and portray the levels of contamination that would be expected to be produced through methamphetamine use, commonly smoking. As such, it is expected that the data might be useful from an environmental exposure perspective and inform further research in this area. The assessment also discusses its potential as evidence in criminal cases where there may be discrepancies concerning the source of the methamphetamine contamination in relation to \"Use of premises\" and associated charges under Section 12 of the Misuse of Drugs Act (New Zealand) 1975. Regardless, the final New Zealand standard, released in June 2017, set a single decontamination level for \'high-use areas\' of 1.5μg/100cm2 and a less stringent decontamination level for \'limited-use areas\' of 3.8μg/100cm2, with no requirement to determine the origin of the contamination.