Decomposition analysis of LTREs may facilitate the design of short-term ecotoxicological tests.

This study compared two methods, based on re-analyzed data from a partly published life table response experiment (LTRE), to help determine the optimal approach for designing ecotoxicological assessments. The 36-day LTRE data recorded the toxic effects of cadmium (Cd) and imidacloprid, alone and in combination, on the reproduction and survivorship of aphids (Acyrthosiphon pisum Harris). We used this data to construct an age-classified matrix model (six age classes, each 6 days long) to estimate aphid population growth rate (λ) under each treatment. For each treatment, an elasticity analysis and a demographic decomposition analysis were performed, and results were compared. Despite different results expected from the two toxicants, the elasticity values were very similar. The elasticity of λ with respect to survival was highest in the first age class, and that with respect to fertility was highest in the second age class. The demographic decomposition analysis examined how changes in life-history traits contributed to differences in λ between control and treated populations (Δλ). This indicated that the most important contributors to Δλ were the differences in survival (resulting from both demographic sensitivity and toxicity) in the first and the second age classes of aphids and differences in fertility in the third and the fourth age classes. Additionally, the toxicants acted differently. Cd reduced Δλ by impairing fertility at third age class and reducing survivorship from the second to the third age class. Imidacloprid mostly reduced survivorship at the first and second age classes. The elasticity and decomposition analyses showed different results, because these methods addressed different questions about the interaction of organism life history and sensitivity to toxicants. This study indicated that the LTRE may be useful for designing individual-level ecotoxicological experiments that account for both the effects of the toxicant and the demographic sensitivity of the organism.

A guide for using social media in environmental science and a case study by the Students of SETAC.

BACKGROUND: In the past few years, the use of social media has gradually become an important part of our daily lives. While some might see this as a threat to our productivity or as a source of procrastination, social media as a whole have unquestionably changed the way in which information and knowledge disseminate in our society. SOCIAL MEDIA GUIDE: This article is meant to serve as a guide for scientists who would like to establish their online presence and includes an outline of the benefits of using social media as well as strategies for establishing and improving your presence in social media. Environmental scientists in particular can benefit enormously from this approach, since this field of science deals with topics that directly impact our daily lives. CASE STUDY: To highlight these approaches for our fellow scientists in the field of environmental science and toxicology and in order to better engage with our own peers, we describe the outreach methods used by the student advisory councils of the Society of Environmental Toxicology and Chemistry (SETAC) and how we have worked towards an improved social media presence. In this article we present our initiatives to increase social media usage and engagement within SETAC. This includes joint social media accounts organized by the SETAC student advisory councils from various SETAC geographical units. We also led a course on social media usage at the SETAC Nashville meeting in 2013 and are currently developing other outreach platforms, including high school student-oriented science education blogs. CONCLUSION: The Students of SETAC will continue to increase communication with and among SETAC students on a global level and promote the use of social media to communicate science to a wide variety of audiences.

More ecological ERA: incorporating natural environmental factors and animal behavior.

We discuss the importance of selected natural abiotic and biotic factors in ecological risk assessment based on simplistic laboratory bioassays. Although it is impossible to include all possible natural factors in standard lower-tier ecotoxicological testing, neglecting them is not an option. Therefore, we try to identify the most important factors and advocate redesigning standard testing procedures to include theoretically most potent interactions. We also point out a few potentially important factors that have not been studied enough so far. The available data allowed us to identify temperature and O2 depletion as the most critical factors that should be included in ecotoxicity testing as soon as possible. Temporal limitations and fluctuations in food availability also appear important, but at this point more fundamental research in this area is necessary before making decisions on their inclusion in risk assessment procedures. We propose using specific experimental designs, such as Box-Behnken or Central Composite, which allow for simultaneous testing of 3 or more factors for their individual and interactive effects with greater precision and without increasing the effort and costs of tests dramatically. Factorial design can lead to more powerful tests and help to extend the validity of conclusions. Finally, ecological risk assessment procedures should include information on animal behavior, especially feeding patterns. This requires more basic studies, but already at this point adequate mechanistic effect models can be developed for some species.