Spencer Cushen, Lindsey Graham, Steven Bull, Baylor University, Waco Texas, 76798

Abstract: The objective of the experiment was to examine the overall effects of Fluoride pollution

on reproduction rates of Simocephalus serrulatus. The hypothesis was if S. serrulatus

exposed to 251 mg/L there would be a significant reduction in reproduction. Small

populations of S. serrulatus were maintained in controlled conditions each submerged in

solutions of varying concentrations of sodium fluoride. The general trend showed that as

the concentration of sodium fluoride increased the reproduction rate decreased.

Introduction: Sodium Fluoride is a common constituent in

everyday products including toothpaste,

medications and drinking water. When

experienced in high concentrations Fluoride

ions can be toxic to humans and other

organisms (Anderson, 1946).The hypothesis

was the higher levels of sodium fluoride will

cause a change in reproductive behavior.

Methods and Materials: • 12 containers (1L) were set up as 3

variables and 1 control with 3 trials each.

• The control group contained Lake Waco

Wetlands water filtered with a 120 micron

mesh filter to remove zooplankton; as were

the experimental groups A,B and C with

added concentrations of (100, 158 and

251mg NaF/L respectively). These

concentrations were based off the values

used in Fiesers’ experiment.

• The test was conducted over 3 weeks on a

12-12 light cycle at room temperature. The

first week was to allow the 10 S. serrulatus

per container to mature and become

reproductively active. Counts of overall

organisms were conducted both of the

following weeks. The babies were removed

and the 10 adults were returned to the

containers.

Conclusion & Discussion: Due to the common dispersal of Sodium Fluoride in water the effects

this pollutant has on S. serrulatus could have a correlation to toxicity in

humans when exposed in high concentrations. In comparison to the

findings of Fieser et al the results were similar however we performed a

field type experiment instead of the sterile technique type where

filtered wetlands water was used instead of double distilled water with

nutrients added. Although a different species this contributes to the

credibility of their findings by corroborating the reproduction numbers

seen in their Daphnia magna cultures by the reproduction numbers of

S. serrulatus (Fieser et al, 1986). Measuring the effect of sodium

fluoride on S.serrulatus allows for a better understanding of the way

pollutants released as byproducts of industrial activity makes an

impact on local ecosystems.

Acknowledgments: A special thanks to Dr. Marty Harvill; Nora Schell, Lake Waco

Wetlands coordinator and Baoqing Ding.

Literature cited : Anderson, B. G. (1946). The toxicity Thresholds of Various Sodium Salts Determined by

the Use of Daphnia Magna. Sewage Works Journal, 82-87.

Fieser, A. H., Sykora, J. L., Kostalos, M. S., Wu, Y. C., & Weyel, D. W. (1986). Effect of

Flouride on Survival and Reproduction of Daphnia Magna. Journal (Water Pollution

Control Federation), 58(1), 82-86.

0

10

20

30

40

50

60

Control 100mg/L 158mg/L 251mg/L

Co

un

t o

f S

.se

rru

latu

s

Concentration of Sodium Fluoride

S.serralutus reproduction count over a one week interval in

varying concentrations of Sodium Fluoride

Figure 2

Figure 1

Figure 3