Adopting a novel method, Griffith University is putting chemicals under the microscope to determine the impact agricultural pesticides and other pollutants in run-offs are having on our iconic marine life.
Dr Jason van de Merwe and his colleagues from Griffith’s ARI-TOX program have created a unique way of testing the chemical toxicity in turtles, dolphins, whales and other marine wildlife, without doing any harm to the animals.
Dr van de Merwe obtains small tissue samples from animals in the wild, those being examined as part of other research projects or with Griffith’s partner organisations such as Sea World and Australia Zoo, or those that are found deceased.
Cells are then cultivated in the lab from these tissue samples, before being exposed to various chemicals to assess their effects.
“We know very little about the effects of chemicals in larger animals like turtles because we can’t easily bring them into the lab to conduct traditional toxicity testing,” Dr van de Merwe said.
“But we can establish their cell cultures in the lab by adding very small tissue samples to the right media under the right conditions, and waiting for the cells to start growing. This gives us a large, growing cell culture which we can keep frozen until we are ready to use them in cell-based toxicity tests.”
“We expose the cells to chemicals of interest, and measure the response of the cells. This provides important information that enables us to understand the effects of those chemicals in these large, often threatened animals.”
While cell-based testing is often used in human health risk assessments, a global shift away from whole-animal testing towards cell-based toxicology has prompted the unique process by ARI-TOX to be applied with an environmental health perspective.
Previous research published by Dr van de Merwe’s ARI-TOX team found pesticide chemicals were present in the sands of Mon Repos near Bundaberg in Queensland, which is a well-established turtle nesting site and popular tourist destination.
Ongoing research by the team in the Mon Repos nesting area aims to examine what levels of pesticides could do the baby turtles harm.
“We know chemicals are getting into these animals. There have been lots of studies that analyse the chemicals accumulating in them. But they’re opportunistic largely, where the samples have come from stranding events,” Dr van de Merwe said.
“And there’s very little information on whether those chemicals could have caused those strandings, or if there are any other health effects of these chemicals on these animals.”
“That’s what we are aiming to find out. Our novel and ethical approach to toxicity testing in marine wildlife will generate a greater understanding of how the chemicals we use affect them, which will contribute to their conservation and management.”