Monthly Archives: October 2021

Integrating Knowledge on the Distribution and Maternal Transfer of Organic Pollutants to Advance Sea Turtle Conservation

The following post is one of a series previewing the research that will be presented at the SETAC North America 42nd Annual Meeting (SciCon4), 14–18 November 2021.

A guest post by Cynthia C. Muñoz and Peter Vermeiren, Radboud University, The Netherlands

Knowledge regarding the internal distribution and subsequent maternal transfer of organic pollutants—such as polychlorinated biphenyls (PCBs), once used in electical equipment and plastics; organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs), which make materials nonflammable—within organisms is of critical importance to scientists who interpret tissue-specific biomonitoring results and refine risk assessments. Although the manufacture and/or use of most of these chemicals were banned decades ago, they persist in the environment and accumulate in wildlife. This is particularly true for long-lived organisms, such as sea turtles, where pollution burdens build up over time and affect health later in life. Moreover, organic pollutants can accumulate over many years before being transferred from the mother to its offspring, where they can interfere with critical development processes. For example, maternal transfer of organic pollutants into yolk, through the placental barrier, or during lactation has been linked to decreased survival rates and impaired embryo and juvenile development in several long-lived vertebrate species. Yet knowledge on the internal and maternal distribution of organic pollutants remains limited for many such species, due to ethical, economic, and logistical restrictions on sampling them, as many are threatened or endangered. Additionally, a diverse chemical universe of legacy, new, and emerging organic pollutants is present in the environment, of which the behavior within the environment and upon contact with long-lived species is largely unknown. In short, the challenge of refining risk assessments specific to the characteristics of long-lived species, such as sea turtles, is complex, without an easy solution.

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We Should Take a Holistic Approach to Environmental Risk Assessment Following Oil Spills

A guest editor post by Sharon Hook, CSIRO Oceans and Atmosphere

With the recent pipeline leak in the waters off of Orange County, California, USA, oil spills are once again in the headlines. We are hearing the concerns of the affected communities about what the consequences of this spill will be for wildlife, fisheries, and safe use of the beaches. After all of the decades of oil spill-related research, there is still a lot of uncertainty about the environmental impacts of oil spills. It is a good opportunity, to ask ourselves as environmental scientists, if we are asking the right questions in our research into the impacts of oil spills, and if we are setting up our studies with the most environmentally relevant approaches.

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Evolution by Pesticides: Evidence of Evolution in American Alligators Affected by Endocrine Disrupting Chemicals

The following post is one of a series previewing the research that will be presented at the SETAC North America 42nd Annual Meeting (SciCon4), 14–18 November 2021.

A guest post by Yeraldi Loera, Ph.D. student at Princeton University

Baby alligator rests in open palm.
Solo gator. Photo courtesy of the author.

Instances of environmental pollution by manufactured contaminants are widespread across the globe. Pesticides are commonly used in agriculture to combat pests, but can also harm other, non-targeted organisms. Exposure to some pesticides can lead to disruption in the endocrine system, altering reproductive development and fitness. One study showed this kind of disruptive effect across populations of American alligators (Alligator mississipiensis) that were exposed to a pesticide (DDT) spill in Lake Apopka, Florida. Surprisingly, another study in the same region showed a rebound in the population following their exposure, suggesting possible evolved resistance to pesticide contamination.

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