Assessment of chronic toxicity of petroleum and produced water components to marine organisms, final technical summary
Year: 1993
Type: report
Abstract: BACKGROUND: The largest discharge associated with offshore oil and gas production is produced water.In the Santa Barbara Channel, produced water is discharged into the coastal environment in 10-15 meters of water.As long-term effects on reproduction and development of marine organisms can often be subtle, it is difficult to assign cause-and-effect relationships amid the background of natural variability, particularly in an environment such as the Santa Barbara Channel where multiple complicating factors are present.Such high level of variations limits our ability to detect subtle impacts of contaminants.However, if the mechanism of action of toxicants under controlled laboratory conditions me better understood, the observed pattern of bioeffects in the natural environment can be more directly linked with specific contaminant(s).Such a marriage of laboratory and field studies must take place in order to achieve scientifically valid information that is also environmentally relevant.Among the myriad of effects that can be measured, gametogenesis and embryonic development are catago"iies that deserve special attention because of their relevance to effects at the population level.A mechanistic understanding of contaminant effects on cellular functioning during gametogenesis and embryonic development are generally uncleaq understanding these is required for linking laboratory bieffects with field observations.Biological field surveys alone may not detect the cause of population changes in polluted environments due to the presence of other complicating factors.It has been suggested that the most promising approach would be to relate molecular and cellular alterations to individual-level physiological changes that lead to perturbations of reproduction and embryonic development.These effects are then relatable to potential impacts at the population level.OBJECTIVES: 1) To determine the effects of produced water exposure in early life stages of marine plants and animals, at the cellular, subcellular, and physiological levels; 2) To determine reproductive tissues.This research demonstrated that the noninvasive NMR approaches (31P NMR spectroscopy and lH NMR imaging), together with correlative histological analysis, provided reliable assessments of gender-speciilc gametogenesis in mussels.Spec~lca.lly, in vivo 31P NMR revealed a spectilc phosphodiester indicator for oogenesis, in addition to providing information on gonadal energy budget.In a complementmy fashion, lH NMR imaging enabled the distribution density of developing gametes across the entire gonad to be monitored.When applied to follow the effect of PW exposure on mussel, both methods revealed the dynamics of chronic ovarian perturbations on the same individual, thus eliminating interferences arising from intrinsic heterogeneities in oogenesis of this species.Consequently, reliable conclusions could be drawn from a much smaller sample size.The changes observed suggest that PW exposure perturbed ovarian energy balance and caused ovarian degeneration in M. cali$ornianus.To the best of our knowledge, this is the first direct demonstration of perturbations in reproduction of organisms chronically exposed to PW under controlled laboratory conditions.
DOI: 10.67297/00041f
Authors: GN Cherr, TW Fan, RM Higashi, J Shenker
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
OpenAlex ID: W217059026