The Study
Researchers from San Diego, US, analysed about 100 water samples over a seven-year period. They found that samples from urban areas tested positive for caffeine.
0.052 AND 8.5 micrograms of caffeine per litre in samples from untreated sewage
0.029 TO 1.19 microgrammes of caffeine per litre from samples taken near active septic systems ranged from.