# Wastewater from an Australian campus of 30,000 shows oxidative stress marker rise during exams

- Published: 2026-11-11 16:55 UTC
- Section: Life & Health › Medicine
- Tags: wastewater surveillance, examination stress, 8-hydroxyguanine, oxidative stress biomarkers, antidepressant consumption, university campus, difference-in-differences, paraxanthine, acesulfame, mental health monitoring
- URL: https://realtech.media/news/rt-814c0c1f473d2e908b21b723_wastewater_from_an/

**Researchers analysed wastewater from a campus of about 30,000 people in 2022 and found a university-specific rise in 8-OHG during exams; antidepressant trends were not significant.**

![Wastewater from an Australian campus of 30,000 shows oxidative stress marker rise during exams](https://realtech.media/media/2026/11/ae343a560166fcba.jpg)
*gigazine.net*

A study published on nature.com reports that wastewater from an Australian university campus carries a measurable chemical signature of examination stress. Samples were collected in 2022 from a campus of about 30,000 people. The authors compared the examination period with teaching periods and with a contemporaneous general-population catchment of about 120,000 residents [1].

The motivation, according to the authors, is that academic stress may affect mental health and coping behaviours, while population-level monitoring relies on self-reports or prescription data with limited temporal resolution [1].

## Biomarkers measured in wastewater

The team analysed oxidative stress biomarkers, antidepressants and attention deficit hyperactivity disorder medication. They also measured behavioural indicators: alcohol, nicotine and tobacco biomarkers, paraxanthine (a caffeine biomarker) and acesulfame [1]. Temporal patterns during the examination period were compared with teaching periods and with the general-population catchment using a difference-in-differences analysis [1].

## What changed during the examination period

The analysis showed a marked university-specific increase in 8-hydroxyguanine (8-OHG). Evidence for 8-hydroxy-2′-deoxyguanosine (8-OHdG) was weaker [1]. Antidepressant consumption trends were consistently positive but not statistically significant [1].

Ritalinic acid and amphetamine, total nicotine and tobacco-derived nicotine, and alcohol remained relatively stable. Paraxanthine and acesulfame decreased significantly [1].

The signal reflects the whole sewage catchment of the campus, with about 30,000 people, compared against a general-population catchment of about 120,000 residents [1]. The authors conclude that, by integrating multiple biomarkers, wastewater surveillance can serve as a non-invasive and complementary tool for identifying periods of increased mental health burden in university populations and for informing timely public health interventions [1].

## Sources

1. [nature.com](https://www.nature.com/articles/s44221-026-00735-5)
2. [gigazine.net](https://gigazine.net/news/20261111-sewage-chemical-signature-university-exams)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-814c0c1f473d2e908b21b723_wastewater_from_an/