Date of Award


Degree Type


Degree Name

MS Biology




Carolyn Bentivegna


Toxicity, Cadmium, Chironomid, Molecular biomarkers, Heavy metal toxicants


Effects of cadmium (Cd), a heavy metal contaminant, on hemoglobin were investigated in aquatic midge fly larvae of the Family, Chironomidae. In this study, chironomid populations from one polluted site, Kearny Marsh, New Jersey, two reference sites, North East Creek, and Bass Harbor, ME, and a laboratory population were taxonomically identified and tested for their sensitivity to Cd. Heavy metals in tissue, water and sediment were analyzed using Atomic Absorption Spectroscopy. Water quality at each site was assessed by measuring pH, dissolved oxygen (DO), oxidation-reduction potential ( eH), salinity and temperature. Hemoglobin proteins in individual larvae were easily detected using polyacrylamide gel electrophoresis (SOS-PAGE). As a model heavy metal toxicant, the effect of Cd on the different hemoglobin proteins was investigated using the following concentrations; 0 µM, 0.3 µM, 3.0 µM, and 30.0 µM. Exposure times included O h and 96 h. Hemoglobin band profiles from each individual were distinguished by the presence or absence of bands as well as band intensities and compared to other individuals at different times and concentrations. Results showed that the expression of band profiles varied as concentrations of Cd and duration of exposure time increased. It was noted that the low molecular weight hemoglobin proteins (< 11 KO) became lighter and/or disappeared in many individuals. This overall trend suggested that the expression of hemoglobin band profiles could give useful information for detecting presence of heavy metals in field studies.