Effect of an Aspartame-Ethanol Mixture on Daphnia magna Cardiac Activity

Aspartame in conjunction with alcohol has been shown to increase the blood alcohol level in humans faster than alcohol and sucrose (Wu et al., 2006). To determine the potential effects of various mixtures of ethanol and aspartame on the nervous system, the heart rate of Daphnia magna (D.magna, water flea) was measured in deionized water (control), ethanol, aspartame, and five different mixtures of ethanol and aspartame. The heart rate was chosen as a representative measure since it is controlled by the nervous system and the heart rate of D.magna can easily be measured. The results were statistically evaluated by student’s t-test. A significant increase in heart rate was observed for all mixed assays compared to both control and ethanol, but not to aspartame. The data suggests that the aspartame and alcohol mixture have a greater effect on D. magna heart rate than water or ethanol, but not aspartame alone. We propose that alcohol in combination with aspartame has potentially detrimental consequences for the nervous system.