Occurrence and Ecological Effects of Amphetamine Type Stimulants
A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Natural Resource Sciences, Under the Supervision of Professor Daniel Snow. Lincoln, Nebraska: May 2015
Copyright (c) 2015 Alexis M. Paspalof
The presence of pharmaceuticals, illicit drugs and their bioactive metabolites in aquatic environments has become an increasingly important topic worldwide, and their potential ecological effects are essentially unknown. The focus of this thesis is on several compounds identified as amphetamine type stimulants (ATSs). Although ATSs have been measured in aquatic ecosystems, in general our knowledge of their occurrence in ecosystems is not well characterized. To broad our understanding of ATS occurrence this thesis provides information from the summer of 2013 and 2014 as to the presence of ATSs and several other pharmaceutical compounds in two different watersheds. These two locations included the highly populated Hudson River Basin, in New York and the Gwynns Falls watershed in Baltimore, Maryland. These two watersheds were chosen based upon two factors: each had sample locations that were part of existing long-term ecological studies and the shortage of published data indicating contamination from ATSs. Amphetamine (AMPH) was detected at one HRB site in 2013 and consistently detected in all BES sites in 2014.
To study the potential effects of ATSs on aquatic ecosystem function and their degradation within the water column, we experimentally exposed microbial biofilms to environmentally relevant concentrations of amphetamine (AMPH). After 3 weeks of exposure, AMPH suppressed gross primary production and community respiration, despite a significant decrease in the parent compound. Based on field and laboratory work, chronic exposure to environmentally relevant concentrations of ATSs and other pharmaceuticals may affect ecosystem functions and the organisms that depend on these functions.
It is widely known that ATSs affect dopamine (DA) production in higher organisms. Current literature indicates the presence of DA in marine algae. This study reports the biological effects DA has on freshwater algae at concentrations similar to environmental concentrations in marine environments.
Advisor: Daniel Snow