World Environment Day this year focuses on fighting the illegal trade in wildlife products. This is because the trade of threatened or endangered species is of increasing global concern, and monitoring it could include using scientific measures. By measuring stable isotopes in wildlife products such as ivory from endangered elephants, scientists can identify where the animal lived. This is the focus of an IAEA project that started earlier this year.
“Stable isotopes could play an important role in the protection of endangered species and threatened habitats,” said David Osborn, Director of the IAEA Environment Laboratories. “Science-based tools can offer support to monitoring programmes and confirm that statements of origin are accurate.”
The isotopic composition of ivory provides information about what an elephant ate and drank, providing scientists with information on the environment in which the animal lived. The stable isotopes of hydrogen and oxygen in water have a characteristic global pattern: when an elephant drinks, the isotopic signature of that water is preserved in its tusks. By analysing the isotopic composition of ivory, scientists can determine the probable geographical origin of an elephant, which in turn could help enforcement agencies identify regions where poaching is taking place and enable them to allocate resources in the right areas to cut off the ivory trade at its root. Certain isotopes can also provide information on the age of ivory and could help assess whether the animal was killed before the ban on trade was implemented.
The same methods can be applied to the illegal trade of protected wood species. International timber eco-certifications are not always reliable due to the lack of trustworthy information as to the exact source of timber, information which is necessary to verify that it is harvested sustainably. The hydrogen isotopic composition of wood reflects the hydrogen isotopic signal of rainfall revealing where the tree was grown.
IAEA reference material
The IAEA is currently developing reference material that could help laboratories worldwide assess the origin of timber. It provides about a hundred different reference materials to over 700 analytical laboratories each year for calibration and quality control of equipment, method validation and training. These materials are used in analytical areas like stable isotope ratio measurements, radionuclides, trace elements and organic pollutants. Available reference matrices cover a range of materials and pure substances including dried marine biota tissues (fish, mussels, seaweed), marine sediment, marble, ancient wood and dried cabbage powder.
The IAEA also helps develop analytical methods and provides training on isotopic and nuclear techniques. IAEA scientists, for example, have recently started an inter-laboratory comparison test for ivory to check several laboratories’ proficiency at analysing ivory samples with the use of stable isotopes. These science-based tools can contribute to reinforcing environmental monitoring programmes and help decision makers allocate resources where they are needed to combat the trade of endangered species.