Hospitals, farms/aquaculture and household wastewater continuously
release trace antibiotics (amber particles) into the river. They
drift downstream with the current, and where the river passes
through the treatment stage a fraction is removed depending on
the chosen technology. Bacteria living along the riverbed sample
the local concentration continuously — once it stays above their
minimum inhibitory concentration (MIC) for long enough, some
mutate into antibiotic-resistant strains (turning from blue to
red), modelling how antimicrobial resistance (AMR) spreads
through contaminated water.
C' = ΣEᵢ·(1−η) − k_mix·C (advection carries C downstream at the flow speed)
p(mutate) = 1 − e^(−k·(C/MIC)·Δt) (resistance risk grows above the MIC)
η: none 0% · activated carbon ≈55% · ozonation/AOP ≈85% · combined ≈95%
- Antibiotic release — combined emission rate E from the active sources before treatment.
- Hospital / Farm / Household — toggle each contamination source on or off independently.
- Treatment stage — removal efficiency η: activated-carbon adsorption, ozone/peroxide advanced oxidation (AOP), or a combined biological + physico-chemical scheme.
- River flow speed — how fast molecules are carried from source to treatment plant to outlet.
This mirrors the real risks described alongside this simulation:
antimicrobial resistance, disrupted aquatic microbiomes and
chronic effects on river organisms, and the real treatment
technologies used to cut them — activated carbon and membrane
filtration, ozone/peroxide/photocatalytic advanced oxidation, and
combined biological + physico-chemical schemes.