Chronic Exposure of Larval Grass Shrimp (Palaemon pugio) to Two Per- and Polyfluoroalkyl Substances

Per- and polyfluoroalkyl substances (PFAS) are synthetic compounds known for being resistant to biodegradation and thus bioaccumulate in humans and wildlife. Perfluorohexane sulfonic acid (PFHxS) is used in cleaning products, stain-resistant textiles, and firefighting foams. Perfluorohexanoic acid (PFHxA) is used in paper products and stain-resistant textiles. Both compounds have been found in surface, ground, and drinking water. The objective of this experiment is to observe how these two compounds affect the life cycle of larval grass shrimp (Palaemon pugio) after 96 hours of acute exposure. Grass shrimp are found along the East Coast in tidal marshes and make up a large percentage of macrofauna density in estuaries. Furthermore, grass shrimp are both primary and secondary consumers and are an important part of the diets of many fish species. Because of these facts, any changes to the larval grass shrimp can affect the ecosystem as a whole. After exposing the grass shrimp to each PFAS compound for 96 hours, the shrimp were observed daily to keep track of how much and how often they molted. Data from the experiment was obtained by tracking mortality, molts, days until reaching the post-larval state, and dry weight of the postlarval shrimp. Results from the PFHxS test showed that, on average, increasing the concentration of PFHxS caused the average days to post-larval state to increase. For the PFHxA test, no significant differences were observed in the parameters measured.

For more information: mlneldne@eckerd.edu