Dolphins and humans are both mammals, they have similar behaviors, “social networks” and their diet includes a large proportion of species from the sea. But unlike us, dolphins are exposed to threats such as and evolve in poor quality water 24 hours a day because of the Human.

Our ecological and physiological similarities make dolphins an important "sentinel species" not only to warn us of health risks, but also to help us understand how new medical discoveries can be taken advantage of.

Researchers from NOAA, the main US agency responsible for the protection of dolphins in the wild which supports national and international projects aimed at studying marine mammal health problems, recently discovered that bottlenose dolphins living in the estuaries of the coast of Georgia had the highest levels of polychlorinated biphenyls (PCBs) ever observed in marine wildlife. The term PCB encompasses a series of persistent contaminants that have been banned in the United States since the late 1970s due to their adverse health effects. The extraordinarily high levels of PCBs measured in dolphins, a peak concentration of 2,900 parts per million, may inhibit their immune function.

Last August, the team conducted a dolphin capture-release medical study on this population and found decreased thyroid hormone levels, elevated liver enzymes and an indication of suppressed immune function.

Researchers are investigating whether populations of coastal dolphins and human communities sharing the same seafood resources are at similar risk.

Dolphins may offer clues to treating diabetes in humans

Research conducted in part by the National Marine Mammal Foundation (NMMF), a non-profit organization, has uncovered evidence that bottlenose dolphins may be the first natural animal model for type II diabetes. Further study of their genome could elucidate a possible treatment for a disease that accounts for around 5% of all human deaths worldwide, according to the World Health Organization.

These studies showed that healthy dolphins seemed to easily turn on and off a diabetes-like state, as needed. This “switching” mechanism is probably due to the diet very high in protein and carbohydrates. Analyzes revealed that a fasting mechanism in dolphins can trigger a range of changes in serum chemical properties that match those seen in humans with diabetes.

These studies also show that humans and dolphins may have similar outcomes when it comes to chronic diseases associated with diabetes, such as insulin resistance, hemochromatosis (iron overload), and kidney stones.

NOAA researchers have also found that exposure of laboratory animals to a toxin produced by microscopic sea algal blooms can cause seizures and eventually lead to epilepsy in almost all animals tested.

The researchers also worked on captive and wild marine animals. After realizing that some sea lions were having seizures when there was no harmful algal bloom, researchers began to believe that poisoning with domoic acid, a neurotoxin produced by the algae Pseudo -nitschia australis, may have evolved into a chronic epileptic disease.

Establishing this new link between the oceans and health offers a new perspective for researchers and clinicians studying human epilepsy.

The type of epilepsy resembles that of humans, as confirmed by at least one human case linked to the consumption of mussels contaminated with domoic acid toxin.

This research could provide important information about how dolphins and other species, including humans, respond to domoic acid poisoning. Dolphins stranded with high levels of domoic acid do not survive long enough to be treated and studied. It is possible that the initial acute poisoning could lead to sudden death. However, these new findings indicate that animals that survive an initial seizure are likely to develop neurological disease with behavioral changes and increasing severity of spontaneous seizures. This new information can help guide future research and emergency response efforts during the next harmful algal bloom event.

By studying the biology of dolphins learn about how viruses infect humans and land animals. This research could help prevent epidemics.

Human papillomavirus has been found to be common among bottlenose dolphins and probably represents the first natural model of papillomavirus outside of humans. Commonly known as HPV in humans, the virus has always caused great health risks including cervical tumors or cancer in women, especially women with multiple HPV types. This new study shows that although dolphins also harbor several types of papillomaviruses, they do not appear to have cancer, only genital warts. Further research on the genome of this virus in dolphins could help understand, manage and prevent cervical cancer in humans.

The health of marine animals and the ecosystem is linked to public health and well-being. We are all concerned, all connected. It is up to us to protect them, to protect ourselves….