Drug checking: Reducing risks at festivals and protecting against the opioid crisis

Summer brings the peak of the festival season and with it the recurring question of how to reduce the risks associated with the use of addictive substances at mass events. International evidence has shown for more than a decade that drug checking, i.e. the chemical analysis of samples of substances directly at the event site, is one of the most effective tools available for reducing risks in this environment. In 2026, the topic becomes even more urgent as the European illegal market is changing towards synthetic opioids, the presence of which is often completely unknown to drug users.

Context

Drug checking changes the behavior of users when the result of the analysis does not meet expectations. At the Boom festival in Portugal, 94.3 percent of the service's clients stated that they do not consume the substance after an unexpected result, and even in the case of adulterants detected in an otherwise confirmed substance, almost a third took the same step (Valente et al., 2019). A follow-up study in England confirmed that these intentions translate into actual behavior: over half of clients discarded samples identified as different from expected ones, and two-fifths reported a reduced dose of confirmed substances at three-month follow-up (Measham & Turnbull, 2021; Measham & Simmons, 2022). A similar, albeit slightly weaker, effect was observed in a Canadian study of an electronic festival (Mema et al., 2018).

The second function of drug checking is market monitoring. Canadian, Portuguese, Chilean, and Mexican services have repeatedly detected dangerous adulterants, including fentanyl in cocaine and MDMA at a Mexican festival (Cruz et al., 2023), or high levels of contamination in psychedelics and stimulants in British Columbia (McCrae et al., 2019). The Dutch Drug Information and Monitoring System, operational since the 1990s, demonstrates that a long-term, publicly funded system can monitor market developments and contribute to a decrease in the incidence of the most dangerous substances (Day et al., 2018).

Demand from festival-goers is high: in Australia, 86.2 percent of respondents supported free drug checking and 87.1 percent would use the service if it were available (Day et al., 2018). At the same time, methodological limitations repeatedly highlighted in the current evidence must be taken into account, in particular self-selection of the sample, overrepresentation of men and the absence of randomized studies (Palamar et al., 2021; Scott & Scott, 2020; Kutscher et al., 2024). Fentanyl test strips have a good diagnostic yield, with a false negative rate of around 3.7 percent (Green et al., 2020), while field GC-MS instruments achieve 74 to 86 percent agreement with the laboratory standard at festivals (Frinculescu et al., 2024). These limitations are an argument for methodological refinement of the service, not for its rejection.

Synthetic opioids change the urgency of the issue

Drug checking is no longer just a prevention tool for dance drugs, but is becoming a key element of early warning for nitazenes and other synthetic opioids. Since 2019, the European Early Warning System has detected 23 different nitazenes in at least 21 countries, with seizures continuing to increase in 2023 and 2024 (Giraudon et al., 2025). In Estonia, nitazenes accounted for 48 percent of drug-related deaths in 2023, and in Latvia, the proportion increased from 3 to 29 percent between 2022 and 2023 (Giraudon et al., 2024). Standard fentanyl test strips do not detect nitazenes due to their different chemical structure, creating a major screening gap (Pereira et al., 2025), and even specialized nitazene strips have limitations, including false negatives for desnitazenes (De Vrieze et al., 2024).

The practical impact is illustrated by the Irish experience: overdose clusters in Dublin and Cork led to rapid laboratory identification of N-pyrrolidino protonitazene in heroin sold as powder and the activation of the Red Alert system (Killoran et al., 2024; Killeen et al., 2024). The Irish health service has therefore convened a national alert group and recommended an increase in the budget for early warning and specialized monitoring laboratories (Killeen et al., 2024). Similarly, the Australian service identified N-pyrrolidino isotonitazene in a sample sold as oxycodone and issued a clinical alert within 24 hours and a community alert within 48 hours (Curtis et al., 2025). The context is further aggravated by the decline in Afghan opium production following the ban on poppy cultivation, which, according to experts, increases the risk that synthetic opioids will replace heroin on the European market, similar to what happened in North America (Friedman, 2024). Switzerland therefore identifies the expansion of drug checking as one of the key strategies to avoid such a crisis, in addition to the distribution of naloxone and contact rooms (Iuga et al., 2025).

Situation in the Czech Republic

In the Czech Republic, drug checking at music events remains illegal. There is only one pilot project, the credibility of which was further weakened by the intervention of the police at one of the music events where the service was active. This experience illustrates the structural problem well: without clear legal regulation, drug checking remains dependent on the tacit tolerance of individual organizers and local authorities, and any intervention by repressive authorities can effectively paralyze the project, regardless of its health benefits. In the last election period, our organization submitted an amendment that was supposed to legalize drug checking and place it in a regulated framework comparable to the models applied in Ireland, Austria or Switzerland. The proposal did not pass the legislative process, which means that Czech practice continues to diverge from the trend that can be observed across Europe.

Recommendations

Legislatively anchor drug checking as a legal and regulated health and harm reduction service, with clearly defined operating conditions, provider responsibility and connection to an early warning system similar to the EU EWS, Irish Red Alert or Australian community alerts models.

Accompany the regulation with systematic financial support from the state, because without stable funding the service remains dependent on grant uncertainty and cannot achieve coverage such as the Dutch or Irish system.

When setting both measures, take into account the urgency given by the arrival of synthetic opioids on the European market: fentanyl and nitazene behave fatally in small doses and without on-site laboratory analysis, their presence is practically undetectable with conventional test strips.

Introduce a functional system before the Czech Republic first encounters an overdose cluster similar to the Dublin or Estonian one, instead of reacting to it retrospectively.

Sources

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