An innovative wastewater-based human biomonitoring system
We are exposed to a wide range of chemicals every day, including those from natural and human-made sources. These substances, known as emerging environmental contaminants due to their prevalence and their potential – still mostly unexplored – toxicity to the human body, have a critical impact on human health. One way to assess human exposure is through human biomonitoring, measuring the quantity of these substances and their metabolites in human samples. “The information obtained from human biomonitoring is of fundamental importance for the understanding of the mechanism of the toxic effects observed in humans, for risk assessment and, consequently, for the application of corrective measures, such as public policies, to reduce exposure,” says Nikolaos Thomaidis, professor of Analytical Chemistry at the National and Kapodistrian University of Athens(opens in new window) and NTS-EXPOSURE(opens in new window) project coordinator. Most current biomonitoring systems are costly and time-consuming, however, and raise ethical issues regarding respect for the privacy of volunteers. There is also a lack of knowledge about the metabolism and toxicity of many emerging chemicals, and a need for new biomarkers and bioanalytical methods. In the EU-funded NTS-EXPOSURE project, researchers developed an innovative method for human biomonitoring using wastewater – a sample that contains the majority of human metabolic excretion products, known as biomarkers. “Wastewater is considered as a mirror of a society, which reflects the exposure of humans to various chemicals and lifestyle habits,” explains Thomaidis.
Analysing the chemical composition of wastewater
The NTS-EXPOSURE project, which was supported by the Marie Skłodowska-Curie Actions(opens in new window) programme, developed a novel methodology to assess the health status of a population in specific areas such as big cities. The new analytical approach was designed to retain intact the analytical information contained in wastewater, through the use of specific extraction protocols and state-of-the-art high-resolution mass spectrometry coupled to liquid chromatography. These techniques measure the composition and amount of specific compounds without compromising samples. The NTS-EXPOSURE system extracts chemicals and concentrates the samples to amplify biomarkers. These extracts are then analysed to find compounds within. The project also identified and proposed several new biomarkers for wastewater-based epidemiology.
Linking socio-economic status with public health
The project yielded a range of important results on chemical exposure, and also links to health status and lifestyle habits on a community level. “We have derived interesting conclusions about the impact of socio-economic status to the public health, alterations in pharmaceutical patterns during the first wave period of COVID-19, and the extent of exposure to pesticides with the discovery of new biomarkers,” notes Thomaidis. The system was also used to detect psychoactive substances and their distribution, as well as their patterns in 16 countries. This revealed that the highest consumption of new psychoactive substances (NPSs) was around the New Year holiday, indicating that consumption increases at festivals and parties. “The results suggest that reducing NPS use and protecting public health should not only be done at the national level; it requires an organised global campaign,” Thomaidis adds.
An early-warning system for public health
The project results will complement ongoing research across Europe into wastewater analysis, with the possibility of leading to an early-warning system for health issues in society – and for public authorities to use as a basis for enacting mitigation policies. “The new screening method can provide valuable results for public health assessment, epidemiological studies and environmental issues,” says Thomaidis.
