The Toxicity of Reef Safe V. Non Reef Safe Sunscreen on Mortality of Daphnia major
School Name
Heathwood Hall Episcopal School
Grade Level
11th Grade
Presentation Topic
Environmental Science
Presentation Type
Non-Mentored
Abstract
The purpose of this experiment is to determine whether or not reef safe sunscreen is less toxic than regular sunscreen. This was tested by calculating the mortality rate in Daphnia. The hypothesis for this experiment is, if the toxicity of the 2 sunscreens are tested on Daphnia (0 nanograms, 10 nanograms, 100 nanograms, 1000 nanograms, 2000 nanograms), then the non-reef safe sunscreen will be more toxic than the reef safe sunscreen. The independent variable is the concentrations of sunscreen and dependent variable is the mortality rate of Daphnia. The solutions of sunscreen were made using serial dilutions sense the amount of sunscreen in each solution was so small. Five Daphnia were placed into each petri dish, and there were three petri dishes per solution for both types of sunscreen. The number remaining alive were counted over the course of two days after they were placed in petri dishes. A line graph and the percent mortality rate per group was calculated. No distinctive patterns occurred in the date, but there was a higher death rate in the non reef safe groups than in the reef safe groups. The data is inconclusive so the null hypothesis cannot be rejected.
Recommended Citation
Barron, Catherine, "The Toxicity of Reef Safe V. Non Reef Safe Sunscreen on Mortality of Daphnia major" (2020). South Carolina Junior Academy of Science. 242.
https://scholarexchange.furman.edu/scjas/2020/all/242
Location
Furman Hall 227
Start Date
3-28-2020 9:00 AM
Presentation Format
Oral and Written
Group Project
No
The Toxicity of Reef Safe V. Non Reef Safe Sunscreen on Mortality of Daphnia major
Furman Hall 227
The purpose of this experiment is to determine whether or not reef safe sunscreen is less toxic than regular sunscreen. This was tested by calculating the mortality rate in Daphnia. The hypothesis for this experiment is, if the toxicity of the 2 sunscreens are tested on Daphnia (0 nanograms, 10 nanograms, 100 nanograms, 1000 nanograms, 2000 nanograms), then the non-reef safe sunscreen will be more toxic than the reef safe sunscreen. The independent variable is the concentrations of sunscreen and dependent variable is the mortality rate of Daphnia. The solutions of sunscreen were made using serial dilutions sense the amount of sunscreen in each solution was so small. Five Daphnia were placed into each petri dish, and there were three petri dishes per solution for both types of sunscreen. The number remaining alive were counted over the course of two days after they were placed in petri dishes. A line graph and the percent mortality rate per group was calculated. No distinctive patterns occurred in the date, but there was a higher death rate in the non reef safe groups than in the reef safe groups. The data is inconclusive so the null hypothesis cannot be rejected.
