Carolyn Summerill Bentivegna is a faculty member at Seton Hall University in the College of Arts and Sciences. She believes that SETAC plays an important role in continued education and networking of environmental scientists and has been a member of the HDC-SETAC Board since 2004. Her research laboratory works on techniques for monitoring the environmental health of wild organisms exposed to pollution. These techniques measure sub-lethal changes in biochemistry and or physiology and connect those responses to concentrations of the chemical within the organism. Ideally, the change should reflect the mechanism by which the pollutant is harming the organism as well as represent an impact that could determine the success of its population. Her lab is currently following two lines of study: freshwater toxics in chironomids (larvae of aquatic midge fly) and crude oil toxics in estuary fish.
Past work in chironomid took advantage of their remarkable levels of hemoglobin, which adapts them to living in suboxic sediments. Work with cadmium showed suppression of hemoglobin genes corresponding with reduced levels of the protein. An interesting finding was that the types of hemoglobin proteins found on SDS PAGE gels were indicative of the chironomid taxonomy (Oh et al, 2009). The number of bands and their positions and intensities establish a profile representative of the species. Determining the species is helpful in field studies since many wild chironomids look very similar.
Figure 2. Our laboratory discovered that chironomid hemoglobins separated on a PAGE gel (left) distinguished between species, which are traditionally identified using head capsules (right). The chironomids shown were collected from Bass Harbor, ME. Top row = Dicrotendipes species, bottom row = Chironomus species. L = ladder, top to bottom- 16, 11 and 4 kd. This work was published in 2009 (Oh et al, 2009).
Bentivegna’s newest interest involving chironomids is chemical components of hydraulic fracturing fluid. One chemical added to fracturing fluid is a biocide, tributyl tetradecly phosphonium chloride (TTPC), intended to kill bacteria that clog equipment and degrade other components. This biocide destroys bacterial membranes; therefore, the laboratory decided to investigate its effects on mitochondrial membranes, or more specifically mitochondrial function. This involved developing a novel technique using red (cool) lasers. Red lasers are a tool used in physical therapy to stimulate cytochrome c oxidase to produce ATP in stressed cells. Results showed that the red laser alone increased ATP production by 300%! While concentrations of TTPC as low as 0.15 mg/L inhibited ATP production, which remained similar to levels with TTPC but no red laser. A paper on this work is submitted for publication.
Projects in estuary fish focus on crude oil impacts. Bentivegna’s laboratory developed a process for extracting polycyclic aromatic hydrocarbons (PAHs) from raw menhaden fish oil. The PAH-like compounds were visualized using 3-D fluorescence spectroscopy. Work on menhaden from the Gulf of Mexico (Bevoortia patronus) following the DeepWater Horizon oil spill (Pena et al, 2015) and from the NJ coast (B. tyrannus) following Hurricane Sandy (Bentivegna et al, 2016) are published.
Figure 3. 3-D fluorescence spectra of raw menhaden fish oil and crude oil. Fish oil and crude oil were extracted with 75% ethanol. Spectra of B. tyrannus collected off the coast of NJ (BtNJ2010) and B. patronus collected near Grande Isle, LA (BpLA2011) are shown with a similarly extracted sample of Macondo crude oil.
Most currently, Bentivegna’s laboratory is investigating DNA mutations in the tumor suppressor gene, p53, after exposing killifish (Fundulus heteroclitus) to crude oil in the laboratory. Results of a proof-of-principle experiment show that killifish from Tuckerton, NJ have genetic variability in the DNA binding region of p53 and that crude oil exposure increases adenine to guanine transitions in its coding regions. A paper on this work is submitted for publication.
Another area of interest involves bioinformatics. Bentivegna’s laboratory has published the first transcriptome for menhaden (SRX892008) in the National Center for Biotechnology Information (NCBI) as well as multiple transcriptomes for a project studying the response of killifish gonads to crude oil exposure (PRJNA347472). This work is showing great potential for the discovery of new biochemical pathways associated with crude oil stress.
Research is a team effort and much credit goes to the many students who have worked in Bentivegna’s laboratory. Her students often attend HDC-SETAC meetings where they have the opportunity to share their work and learn more about what opportunities the field of environmental toxicology and chemistry have to offer new scientists.
*Oh JT, Epler JH, Bentivegna, CS. 2014. A rapid method of species identification of wild chironomids (Diptera: Chironomidae) via electrophoresis of hemoglobin proteins in sodium dodecyl sulfate poly acrylamide gel (SDS-PPAGE). Bulletin of Entomological Research 104:639-651
*Pena EA, *Ridley LM, Murphy WR, Sowa JR Jr. Bentivegna CS. 2015. Detection of polycyclic Aromatic Hydrocarbons (PAHs) in Raw Menhaden Fish Oil using Fluorescence Spectroscopy: Method Development. Environmental Toxicology and Chemistry 34 (9):1946–1958.
Bentivegna CS, *DeFelice CR, Murphy WR. 2016. Excitation-Emission Matrix Scan Analysis of Raw Fish Oil from Coastal New Jersey Menhaden Collected Before and After SuperStorm Sandy. Marine Pollution Bulletin. 107:442-452