Adverse Effects of Crack/Cocaine to Marine Organisms Affected by Acidification Conditions

Abstract

After administration, illicit drugs and its metabolites are excreted and reaches the wastewater treatment plants where they may not be eliminated by conventional treatment technologies. Recent research demonstrates they can influence and alter physiology as well as behavior of aquatic organisms. Since 1970, cumulative carbon dioxide (CO2) emissions from fossil fuel combustion, cement production and flaring have tripled, and cumulative CO2 emissions from forestry and other sources have increased by about 40%. Rising atmospheric CO2 concentration is causing global warming and ocean acidification. The inorganic carbon system is one of the most important chemical equilibria in the ocean and is largely responsible for controlling seawater’s pH. Once pH values decreased, organic compound may also suffer some alterations in bioavailability. Based on that, the hypothesis of this work is that the acidification in the marine environment will modify toxicity of the illicit drug cocaine and its byproducts. Aiming to address the effects of the combination of the all different stressors on the organisms used, and besides, to distinguish the effect observed related to each of the stressors, it was developed an integrated, and more precise, interpretation of the risks associated with CO2 enrichment in the marine environment: the multivariate analysis tools. Using Principal Component Analysis (PCA) it was possible to understand the correlation between the biological effects measured in laboratory associated with the concentration of protons and Crack-Cocaine. The experiments have shown negative effects mainly associated with high concentration of protons (lower pH values) and relatively high concentrations of crack-cocaine for all the organisms used in the different assays. This thesis demonstrate that acidification of coastal ecosystems will trigger enhanced adverse effects on marine organisms exposed to drugs.