Discipline: Biological Sciences
Subcategory: Physiology and Health
Session: 4
Room: Exhibit Hall
Aariana Tucker - Norfolk State University
The declining population of amphibians is caused by pollution in their habitats caused by agricultural and pharmaceutical runoff containing harmful chemicals from fertilizers. Ammonium nitrate is an endocrine disrupting chemical found in fertilizers, herbicides, and insecticides that enters waterways from agricultural and pharmaceutical runoff and ground water pollution. The Environmental Protection Agency regulates the amount of endocrine-disrupting chemicals present in drinking water and 10mg/L is the safe amount of ammonium nitrate that is present in drinking water. The recent legalization and medicinal usage of cannabinoids across the nation has raised the demand for cannabinoids derived from hemp and cannabis. Growing cannabis and hemp plants requires a significant amount of water and causes pollution due to agricultural runoff. Cannabinoids are the compounds found in hemp and do not completely metabolize in the body making them present in human waste and are classified as a pharmaceutical pollutant. Waste from cannabinoids is found in the water system which potentially exposes aquatic life to these substances. In this study, the morphological and developmental effects of the cannabinoid CBD and ammonium nitrate were analyzed in Lithobates pipiens. The hormone thyroxine determines the growth rate and initiates metamorphosis that begins in the skin. The Gosner stage developmental chart was used to identify and determine the growth rate and development of pre-metamorphic tadpoles. In this study ten tadpoles were placed in four, 26L tanks with treated drinking water and filters. Pollutants containing 10mg/L ammonium nitrate, 0.6mg /LCBD, and 2.7mg/L of CBD, respectfully, were added to the tanks. The tanks were observed and evaluated for the effects of the bioaccumulation The tanks were tested for pH, nitrate levels and development of tadpoles . Histological analysis performed on the skin and liver demonstrated that the hepatic cells of the polluted tadpoles exhibited damage and few nuclei were visible leading to necrosis. Tadpoles exposed to 0.6mg/L CBD exhibited the same damage to the hepatic cells. A microbial and histological analysis of the tadpole skin exposed to the mandated EPA of ammonium nitrate exhibited peptidoglycan layer of the cell was destroyed and histological the skin was characterized by having zoosporangia between chromatophores and dermis layers. The morphology of the skin observed on the tadpole contained a fungal infection that would cause zoosporangia. The study determined that 10mg/L of ammonium nitrate and 2.7mg/L CBD toxicity yields 80% mortality rate and 0.6mg/L CBD, 30% mortality rate. CBD in normal dosages and is not a pharmaceutical endocrine disrupting chemical and tadpoles to grew normally. In this analysis cannabinoid affected the morphology and physiology of the tadpole. A hepatic analysis showed the physiological effect that both cannabinoids and ammonium nitrate deteriorated the hepatocytes in the liver, leaving very few visible nuclei. This study determines ammonium nitrate is an endocrine disrupting chemical, but CBD is not endocrine disrupting in low amounts, allowing tadpoles to develop into healthy frogs. CBD has potential to be detrimental the aquatic life without environmental protection regulation to protect water systems and aquatic life.
Funder Acknowledgement(s): CSET Research Program
Faculty Advisor: Maureen Scott, mscott@nsu.edu
Role: Over the summer of 2022 I was responsible for taking care of the tadpoles that were observed in this study which included feeding them, maintaining their habitat, cleaning filters, and adding contaminants.