From Boomtown to Wasteland: Bioavailability of Heavy Metals in Tar Creek and Beyond

The area of northeast Oklahoma in Ottawa county was once known for its massive mining industry. Picher field, which later became the towns of Picher and Cardin, was the largest supplier of lead and zinc to the Unites States military for manufacture of ammunition during the 1st and 2nd world wars. Unfortunately, lack of oversight and lack of regulation, combined with an excess of greed caused a mining boomtown to go from a population of nearly 20,000 to zero in just under a century. It took fewer than 60 years for the mines to be depleted and the companies to abandon the giant underground caverns they had dug, leaving the area vulnerable to subsidence. But the sinkholes were not the only problem. In 1980, the water in the creek that flowed through the town began to run orange, and three years later, a 40 square mile area around the mine field became one of the U.S.’s first Superfund sites.

 

It’s been 40 years since Tar Creek was declared a Superfund site by the U.S. Environmental Protection Agency (EPA), and the water still runs orange from the continuous flow of water from the mines. Open mine shafts, vents, and exploratory boreholes are a constant source of heavy metal contamination to the creek, and surrounding bodies of water that flow into more well-known and highly trafficked areas, such as Grand Lake O’ the Cherokees. There are several research questions that we are interested in investigating.

 

• The first of which is how the concentrations of heavy metals change with the direction of flow from the most contaminated areas towards the south in the Grand Lake area. Is there a gradient?
• The next question, and more important, concerns the bioavailability of these heavy metals. How much of the metal in the water can enter an organism living in that water? This depends on the total water chemistry, not just the amount of metal present.
• Additionally, are there mechanisms in which the aquatic life have evolved in order to adapt to the harsh conditions of their environment and, if so, what could those mechanisms be?

To investigate these questions, we collect samples from a variety of waters in the region. Samples are used to collect data related to heavy metal concentrations such as lead, zinc, and cadmium as well as other water chemistry parameters needed to predict the bioavailability using the Biotic Ligand Model. Water samples are also used to assess toxicity to fish gill cells cultured in the lab. Fish tissues are collected from the same sources as the water samples to compare the concentrations of heavy metals found in the fish tissues to that of the water where the fish have been living. By participating in our research, you will have the opportunity to develop a variety of skills including cell culturing, how to perform cytotoxicity assays, and how to prepare tissues for RNA extraction and isolation.

 

Network Mentor: Dr. Matteo Minghetti