Tropical Freshwater Species Are Not Being Adequately Protected From Toxic Chemicals

Newswise — More than 75 percent of global biodiversity is found in tropical ecosystems, yet these areas are using data taken from temperate ecosystems for protection from toxic chemicals. A new study highlights concerns and provides direction as to how these sensitive species can better be protected. The study is published in the latest issue of Integrated Environmental Assessment and Management.

Tropical aquatic ecosystems differ ecologically from their temperate counterparts and comprise many more species. Because of this difference in biodiversity, the number of species potentially affected by exposure to pollutants is also greater in tropical ecosystems. Many countries in the tropics and subtropics are developing nations that are heavily populated and rapidly becoming industrialized. These nations typically lack the money, infrastructure and resources for advanced pollution controls.

Investigating the disparity of toxicity between temperate and tropical species, researchers found that such extrapolations are not always protective. Tropical species were more sensitive to 6 of 18 chemicals tested, specifically ammonia, arsenic, zinc, chlorpyrifos, chlordane and phenol. There are almost certainly other chemicals for which tropical data are not available, to which tropical species sensitivities will be greater than temperate species.

The study's authors recommend both developing tropical-specific species sensitivity data and, in the absence of such data, applying a conservative extrapolation factor to temperate data to ensure an adequate level of environmental protection.

To read the entire study, click here: http://www.allenpress.com/pdf/ieam-03-01-049..067.pdf

Integrated Environmental Assessment and Management (IEAM) is the quarterly, international peer-reviewed journal of the Society of Environmental Toxicology and Chemistry (SETAC). The journal's mission is to bridge the gap between applied science and environmental management, regulation, and decision-making.

SETAC is a global professional, nonprofit organization comprised of nearly 5,000 individuals from more than 70 countries in the fields of environmental chemistry and toxicology, biology, ecology, atmospheric sciences, health sciences, earth sciences, and environmental engineering. For more information, please visit http://www.setac.org.