4 research outputs found
Integrating Omic Technologies into Aquatic Ecological Risk Assessment and Environmental Monitoring: Hurdles, Achievements, and Future Outlook
Background: In this commentary we present the findings from an international consortium on fish toxicogenomics sponsored by the U.K. Natural Environment Research Council (Fish Toxicogenomics—Moving into Regulation and Monitoring, held 21–23 April 2008 at the Pacific Environmental Science Centre, Vancouver, BC, Canada).
Objectives: The consortium from government agencies, academia, and industry addressed three topics: progress in ecotoxicogenomics, regulatory perspectives on roadblocks for practical implementation of toxicogenomics into risk assessment, and dealing with variability in data sets.
Discussion: Participants noted that examples of successful application of omic technologies have been identified, but critical studies are needed to relate molecular changes to ecological adverse outcome. Participants made recommendations for the management of technical and biological variation. They also stressed the need for enhanced interdisciplinary training and communication as well as considerable investment into the generation and curation of appropriate reference omic data.
Conclusions: The participants concluded that, although there are hurdles to pass on the road to regulatory acceptance, omics technologies are already useful for elucidating modes of action of toxicants and can contribute to the risk assessment process as part of a weight-of-evidence approach
Effects of Acute Exposure to the Non-steroidal Anti-inflammatory Drug Ibuprofen on the Developing North American Bullfrog (<i>Rana catesbeiana</i>) Tadpole
A variety of pharmaceutical chemicals
can represent constituents
of municipal effluent outflows that are dispersed into aquatic receiving
environments worldwide. Increasingly, there is concern as to the potential
of such bioactive substances to interact with wildlife species at
sensitive life stages and affect their biology. Using a combination
of DNA microarray, quantitative real-time polymerase chain reaction,
and quantitative nuclease protection assays, we assessed the ability
of sub-lethal and environmentally relevant concentrations of ibuprofen
(IBF), a non-steroidal anti-inflammatory agent and prevalent environmental
contaminant, to function as a disruptor of endocrine-mediated post-embryonic
development of the frog. While the LC<sub>50</sub> of IBF for pre-metamorphic <i>Rana catesbeiana</i> tadpoles is 41.5 mg/L (95% confidence interval:
32.3–53.5 mg/L), exposure to concentrations in the ppb range
elicited molecular responses both <i>in vivo</i> and in
organ culture. A nominal concentration of 15 ÎĽg/L IBF (actual
= 13.7 ÎĽg/L) altered the abundance of 26 mRNA transcripts within
the liver of exposed pre-metamorphic <i>R. catesbeiana</i> tadpoles within 6 d. IBF-treated animals demonstrated subsequent
disruption of thyroid hormone-mediated reprogramming in the liver
transcriptome affecting constituents of several metabolic, developmental,
and signaling pathways. Cultured tadpole tail fin treated with IBF
for 48 h also demonstrated altered mRNA levels at drug concentrations
as low as 1.5 ÎĽg/L. These observations raise the possibility
that IBF may alter the post-embryonic development of anuran species
in freshwater environs, where IBF is a persistent or seasonal pollutant