Polycyclic aromatic compounds (PAC) are organic compounds found ubiquitously in the environment and originate naturally or anthropogenically. They are persistent, bioaccumulative, and toxic (PBT). PACs have been found to modulate voltage gated ion channels in fish cardiomyocytes. Many studies have examined PACs effects, however, there is growing concern about a less studied class of PACs: hetero-polycyclic aromatic compounds (HPACs). Quinoline and its derivative 2-methylquinoline are two-ringed HPACs found in high concentrations in sediment and tissues of fishes from the Great Lakes. Studies investigating synthetic quinoline derivatives used in the pharmaceutical industry have shown HPACs modulate voltage gated sodium, calcium and potassium ion channels in cardiomyocytes of fishes and mollusk neurons. We therefore designed a study investigating the acute neurobiological effects of quinoline and 2-methylquinoline on Great Pond Snail (Lymnaea stagnalis) neurons, a model with a large easily accessible central nervous system and well conserved ion channels. Electrophysiological characteristics were measured by performing suction electrode experiments on the right internal nerve of the right parietal Lymnaea stagnalis ganglion. Extracellular recordings before and after application of various quinoline or 2-methylquinoline concentrations were used to determine the frequency of right parietal nerve activity which we normalized as percent of control. The extracellular recordings revealed that quinoline affects right parietal nerve activity in a dose dependent manner. Quinoline caused a statistically significant effect on right parietal nerve activity at 1000 nM, but not 100 nM, and 10 nM, with mean percent of control values being 89.2 ± 4.3%, 103.9 ± 4.6% and 99.9 ± 3.5% respectively. 2-Methylquinoline had no statistically significant effect on right parietal nerve activity at 1000 nM. These experiments highlight the importance of understanding the neurobiological effect of PBT environmental contaminants quinoline and 2-methylquinoline, as well as demonstrate the utility of suction electrode recordings as an electrophysiology technique to evaluate acute neurotoxicity of environmental contaminants.