Occurrence and concentration of caffeine in Oregon coastal waters

• Published in: Marine pollution bulletin 2012-07, Vol.64 (7), p.1417-1424
• Main Authors: Rodriguez del Rey, Zoe, Granek, Elise F., Sylvester, Steve
• Format: Article
• Language: English
• Subjects: Caffeine; Caffeine - analysis; coastal water; coasts; Contaminant; drugs; Environmental Monitoring; estuaries; freshwater; Intertidal; Marine; Oregon; population density; River; rivers; seasonal variation; seawater; Seawater - chemistry; storms; surface water; Water Pollutants, Chemical - analysis; water pollution; Water Pollution, Chemical - statistics & numerical data; Watershed
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2012.04.015

► Caffeine was detected in Oregon coastal ocean waters measuring up to 44.7ng/L. ► Caffeine concentration did not correspond with human population density and pollution sources. ► Caffeine concentrations corresponded with storm event occurrence. ► Caffeine concentrations in rivers and estuaries draining to the coast measured up to 152.2ng/L. Caffeine, a biologically active drug, is recognized as a contaminant of freshwater and marine systems. We quantified caffeine concentrations in Oregon’s coastal ocean to determine whether levels correlated with proximity to caffeine pollution sources. Caffeine was analyzed at 14 coastal locations, stratified between populated areas with sources of caffeine pollution and sparsely populated areas with no major caffeine pollution sources. Caffeine concentrations were measured in major water bodies discharging near sampling locations. Caffeine in seawater ranged from below the reporting limit (8.5ng/L) to 44.7ng/L. Caffeine occurrence and concentrations in seawater did not correspond with pollution threats from population density and point and non-point sources, but did correspond with storm event occurrence. Caffeine concentrations in rivers and estuaries draining to the coast ranged from below the reporting limit to 152.2ng/L. This study establishes the occurrence of caffeine in Oregon’s coastal waters, yet relative importance of sources, seasonal variability, and processes affecting caffeine transport into the coastal ocean require further research.