Field-based approach for assessing the impact of treated pulp and paper mill effluent on endogenous metabolites of fathead minnows (Pimephales promelas).

A field-based metabolomic study was conducted during a shutdown of a pulp and paper mill (PPM) to assess the impacts of treated PPM effluent on endogenous polar metabolites in fathead minnow (FHM; Pimephales promelas) livers. Caged male and female FHMs were deployed at a Great Lakes area of concern during multiple periods (pre-, during, and post-shutdown) near the outflow for a wastewater treatment plant. Influent to this plant is typically 40% PPM effluent by volume. Additional FHMs were exposed to reference lake water under laboratory conditions. A bioassay using T47D-KBluc cells showed that estrogenic activity of receiving water near the outflow declined by 46% during the shutdown. We then used (1)H NMR spectroscopy and principal component analysis to profile abundances of hepatic endogenous metabolites for FHMs. Profiles for males deployed pre-shutdown in receiving water were significantly different from those for laboratory-control males. Profiles were not significantly different for males deployed during the shutdown, but they were significant again for those deployed post-shutdown. Impacts of treated effluent from this PPM were sex-specific, as differences among profiles of females were largely nonsignificant. Thus, we demonstrate the potential utility of field-based metabolomics for performing biologically based exposure monitoring and evaluating remediation efforts occurring throughout the Great Lakes and other ecosystems.

Chloroplast biogenesis: quantitative determination of monovinyl and divinyl chlorophyll(ide) a and b by spectrofluorometry.

Simultaneous equations for the determination of monovinyl (MV) and divinyl (DV) Chl a and b by spectrofluorometry in unsegregated mixtures of these tetrapyrroles were derived. The same equations can also be used for the quantitative determination of MV and DV chlorophyllide (Chlide) a and b in unpurified mixtures, after extraction of the Chls in hexane. The equations used differences in the Soret excitation maxima of these tetrapyrroles in ether at 77 degrees K, in order to correct the Soret excitation overlap between MV and DV Chl(ide) a and between MV and DV Chl(ide) b.