I looked up the MSDS on Stabil. It doesn't sound like 6 oz. in 150 gallons of water will kill you. Might make you wish you were dead.
"Ingestion: Toxicity is relatively low, there is a risk of aspiration of product into the lungs. On ingestion of large quantities, slight GI discomfort diarrhea, and headache may occur. Small doses may produce irritation and diarrhea."
Here is a link to the MSDS: http://www.americanamb.com/ops/1101M...Stabilizer.pdf