Emerging and persistent impacts on Marine Organisms: Detection methods and action mechanisms

Editorial Marine environmental quality and biodiversity The fourth Bilateral Seminar Italy-Japan on "Physical and Chemical Impacts on Marine Organisms - For Conservation of Biodiversity and Sustainability" took place on October 25-26 2010 at Aichi Prefectural University, Nagakute, Japan, and it was quite timely regarding the international recognition of the endangered environment and the worldwide concern for the conservation of biodiversity. The seminar was divided into 5 sections: "Global warming, ocean acidification and emerging pollutants", "Xenobiotic receptors and biomarkers of exposure", "From marine biology to applied biotechnology", "Toxicology of nanoparticles on marine organisms" and "Molecular approaches to marine ecotoxicology". This special issue contains selected papers from presentations given by acknowledged experts and related to: i) actual and changing environmental conditions for marine organisms, ii) action mechanisms of pollutants and harmful chemicals, iii) validation of biological indicators of environmental hazard, iv) use of model organisms for the analysis of pollutants effects, v) introduction of new materials and methods to detect and decrease the impact of pollutants on the marine environment. On behalf of all participants of the seminar, VM and YY hope that the reported results will give a contribution to better understanding the deterioration of the marine environment, and new stimuli to investigate these matters. The first four articles are mini-reviews on hot topics and emerging hazards which have inspired concern in the scientific community. Among these, the manuscript "Global change ecotoxicology: identification of early life history bottlenecks in marine invertebrates, variable species responses and variable experimental approaches" (by Byrne) offers a timely review of methodological issues in global change ecotoxicology of fertilization, embryo and larval developments in marine invertebrates with planktonic stages. Even though the subject is relatively new, the updated review on the impacts of both ocean acidification and rising of seawater temperature is an important milestone in this field of research. The mini-review "Bivalve molluscs as a unique target group for nanoparticle toxicity" (by Canesi et al.) summarizes the effects of nanoparticles in bivalves and the utility of these organisms to assess their potential impact. The authors present the state of the art in this emerging field, elucidating some mechanisms of response exhibited by mussels toward a few types of nanoparticles. The current state of knowledge on the responses of copepods to a range of stress factors is reviewed in "Gene expression patterns and stress response in marine copepods" (by Lauritano et al.), with a particular emphasis on the molecular level. The last mini-review "Toxic effects of engineered nanoparticles in the marine environment: Model organisms and molecular approaches" (by Matranga and Corsi) provides the first valuable collection of papers and main findings specifically addressing the effects of engineered nanoparticles (ENPs) on marine organisms. The authors stressed the importance of monitoring noxious effects of emerging and often neglected pollutants, and the need to fully assess the effects of ENPs in the marine environment. In the manuscript "Algal symbiont type affects gene expression in juveniles of the coral Acropora tenuis exposed to thermal stress" (by Yuyama et al.), it is shown that expressions of stress related genes in the host coral are significantly affected by the symbiont types, with different clades resulting in different levels of gene expression. This is an important contribution toward the understanding of coral bleaching, providing a significant advancement from the application