Exploring Domestic Discharge Patterns in Wastewater through LC-HRMS Screening and Temporal Clustering

Area of Science:

• Environmental Chemistry
• Epidemiology
• Analytical Chemistry

Background:

• Wastewater influent holds epidemiological data but is complex.
• Interpreting wastewater signals for human exposure is challenging.

Purpose of the Study:

• Analyze daily discharge patterns of trace organic compounds in wastewater.
• Identify recurring patterns linked to domestic chemical consumption and population exposure.

Main Methods:

• Hourly composite wastewater samples analyzed over three 24-h periods.
• Liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) used.
• Temporal k-means clustering applied to target and non-target compounds.

Main Results:

• Over 72,000 features identified, with 402 target compounds annotated.
• Five distinct daily discharge patterns identified, two linked to domestic use.
• Morning peak pattern identified, likely associated with morning urine, and extended to non-targeted features.

Conclusions:

• Combining targeted and non-targeted analysis with clustering enhances wastewater data interpretation.
• Discharge patterns provide insights into population chemical consumption and exposure.
• This approach improves the ability to link wastewater signals to human activities.