Discipline: Ecology Environmental and Earth Sciences
Subcategory: Pollution/Toxic Substances/Waste
Damon Ricks - Norfolk State University
Co-Author(s): Michaela Twitty
Lead is a toxic metal that is found naturally in the earth’s crust. There are many sources of lead including corrosion, brass faucets, artificial turf, and explosives, etc. Lead from these sources leech into our nation’s waterways. Lead water pollution is a major environmental issue when water treatment procedures are compromised, leading to elevated lead levels that are detrimental to the health and vitality of human and marine organisms. Low levels of lead cause serious health issues such as, lowering IQ and disrupting development, in children and high blood pressure and infertility in adults. Studies determined that chronic lead exposure can be so lethal that metamorphosis, neurology and other developmental progressions will be inhibited in aquatic organisms. The Environmental Protection Agency (EPA) determined that concern level of lead in water is 0.015 mg/L. In Flint, Michigan, there were high lead levels of 0.0252 mg/L of lead in 95% of their water samples. This study demonstrates the effects of lead acetate on Lithobates catesbeiana development by utilizing the standardized values by the EPA and the amounts found in Flint water samples. This investigation was conducted over a 5-week period; however, the Lithobates catesbeiana pre-metamorphic tadpoles were exposed to a 21-day bioaccumulation of lead water pollution. Ten American bullfrog pre-metamorphic tadpoles were placed in lead polluted aquatic environments containing 26 liters of deionized water with 0.015 mg/L, and 0.0252 mg/L of lead acetate pollutant. This investigation examines lead as an environmental endocrine disruptor by assessing metamorphosis and the developmental changes of tadpoles in all polluted environments. Gosner Staging System for Anurans was used to examine the developmental changes and detect the offset of metamorphosis in the American Bullfrog tadpoles. Lead acetate levels of 0.015mg/L and 0.0252mg/L caused delayed development in pre-metamorphic tadpoles from their progress from GS 26 to GS 42. At the end of the 5-week observation, the lower concentration of lead inhibited development; however, the higher concentration of lead increased the mortality rate. The histological analysis of the tadpoles illustrated significant amounts of toxins absorbed causing liver and GI damage after 3 weeks bioaccumulation of lead. The importance of this study demonstrates that uncontrolled lead water pollution is a threat to the survival and vitality of marine organisms and must be monitored.
Funder Acknowledgement(s): LSAMP; HBCU-UP
Faculty Advisor: Maureen Scott, mscott@nsu.edu
Role: The coauthor and I did all parts of the research, alongside our mentor Maureen Scott.