Here are a few more references with abstracts.
2177. Dallinger,R (1994): Invertebrate organisms as biological indicators of heavy metal pollution. Applied Biochemistry and Biotechnology 48, 27-31.
<Some species of invertebrate animals are known to be efficient accumulators of trace elements. Generally, metal accumulation by such organisms is based on efficient detoxification mechanisms, such as intracellular compartmentalization, or metal inactivation by binding to metallothioneins. Metal accumulators have often been used as accumulation indicators of environmental metal pollution. This means that, ideally, metal concentrations in the animal's body reflect quantitatively or semiquantitatively environmental pollution levels. In reality, however, many factors, such as the animal's weight and age, can disturb such quantitative relationships. These factors have, therefore, to be considered carefully before an invertebrate is utilized as accumulation indicator for metal pollution. Apart from accumulation, many invertebrates exposed to elevated metal concentrations respond to this stress by metal-induced synthesis of metallothioneins. Additionally, metallothionein in metal-loaded organisms can be present in different isoforms that are specifically synthesized in response to different metals. These facts make metallothionein a potential biomarker for metal stress in invertebrates. One possibility may be to assess parameters of metallothionein synthesis at the molecular or biochemical level. Moreover, metallothionein isoform patterns could provide information on different isoforms synthesized in response to different metals or chemicals. In any case, however, care must be taken to consider intrinsic physiological parameters, such as nutritional or developmental factors, which could also interfere with metallothionein synthesis>
2213. Wang,WX; Fisher,NS (1999): Delineating metal accumulation pathways for marine invertebrates. Sci. Tot. Environ. 237-238, 459-472.
<Delineating the routes of metal uptake in marine invertebrates is important for understanding metal bioaccumulation and toxicity and for setting appropriate water and sediment quality criteria. Trace element biogeochemical cycling can also be affected if the rates of metal uptake and regeneration by marine animals are dependent on the routes of metal accumulation. In this paper we review recent studies on the pathways of metal accumulation in marine invertebrates. Both food and water can dominate metal accumulation, depending on the species, metal and food sources. Trace elements which exist in seawater primarily in anionic forms (e.g. As and Se) are mainly accumulated from food. For metals that tend to associate with protein, uptake from water can be an important source. Kinetic modeling has recently been used to quantitatively separate the pathways of metal uptake in a few marine invertebrates. This approach requires measurements of several physiological parameters, including metal assimilation efficiencies (AE) from ingested food, metal uptake rates from the dissolved phase, and metal efflux rates (physiological turnover rates) in animals. For suspension feeders such as mussels and copepods, uptake from the dissolved phase and food ingestion can be equally important to metal accumulation. Metal AE and partition coefficients for suspended particles, which are dependent on many environmental conditions, can critically affect the exposure pathways of metals. For marine surface deposit feeding polychaetes such as Nereis succinea, nearly all metals are obtained from ingestion of sediments, largely because of their high ingestion rates and low uptake from solution. The bioavailability of metals from food and the trophic transfer of metals must be considered in establishing water and sediment quality.>
Note the following study was done using "mesocosms" = aquaria.
2214. Breitburg,DL; Sanders,JG; Gilmour,CC; Hatfield,CA; Osman,RW; Riedel,GF; Seitzinger,SP; Sellner,KG (1999): Variability in responses to nutrients and trace elements, and transmission of stressor effects through an estuarine food web. Limnology and Oceanography 44, 837-863.
<Aquatic systems are increasingly exposed to multiple stressors from anthropogenic sources. These stressors can vary in the consistency and magnitude of responses they elicit in biota and in how the presence of additional stressors modifies their effects. Understanding how the biological environment and temporal dynamics influence responses to stressors, and how stressors interact, is important to predicting their effects in the natural environment. We examined temporal variability in responses of an experimental estuarine food web to elevated trace elements and nutrients, as well as non-additive effects of the combination of these two stressors. Experiments were conducted four times during spring through autumn 1996 in 20 l-m3 mesocosms. We measured a range of system-, population-, and individual-level parameters to quantify responses of phytoplankton, bacterioplankton, heterotrophic nanoflagellates, copepods, fish, and benthic invertebrates to trace element and nutrient additions. The response to trace element additions was more variable both temporally and among phytoplankton and higher trophic level taxa than was the response to nutrient additions. Most taxa increased, either significantly or showed a trend toward increasing, in response to nutrient additions in all four mesocosm runs. In contrast, the direction as well as the magnitude of responses to trace element additions varied considerably among taxa and experimental runs. Two distinct types of nutrientXtrace element interactions were important. First, temporal dynamics of nutrient ratios appeared to affect the temporal pattern of toxicity of trace elements to phytoplankton. Second, in the June mesocosm run when trace element additions reduced production, abundance, or growth of many organisms, these reductions were often proportionately greater in nutrient addition tanks than where no nutrients were added. Our results suggest that considerable temporal and taxonomic variation in responses to trace element loadings are likely to be seen in field settings even under constant loadings to the system and that trace elements may mask the magnitude of the response to high nutrient loadings in eutrophic systems. More generally, the presence of multiple stressors may either increase or dampen the temporal and spatial variability seen in aquatic systems, depending on the interactions among stressors and the influence of background environmental conditions and sensitive species on the expression of stressor effects.>
2227. Wang,WX; Stupakoff,I; Fisher,NS (1999): Bioavailability of dissolved and sediment-bound metals to a marine deposit-feeding polychaete. Mar. Ecol. Prog. Ser. 178, 281-293.
<Assimilation efficiencies (AEs) of trace elements (Ag, Cd, Co, Se and Zn) in a marine deposit-feeding polychaete, Nereis succinea, from ingested sediments were measured using a pulse-chase radiotracer feeding technique. Radiolabeled sediments were encapsulated and fed to the worms for 1 h, after which the worms were allowed to depurate their ingested materials for 3 d. The ranges of AEs were 12 to 36% for Ag, 5 to 44% for Cd, 35 to 96% for Co, 29 to 60% for Se and 21 to 59% for Zn. Trace metal assimilation was little affected by sediment source and sediment grain size. Metals (Ag, Cd, Co and Zn) associated with anoxic sediments were assimilated with a significantly lower efficiency than metals from oxic sediments. The AE of Cd decreased with the duration of sediment radiolabeling; AEs of Ag, Co, Se and Zn were weakly affected by sediment aging. Metal uptake in worms from the dissolved phase was proportional to metal concentration in the dissolved phase, although there was some evidence of Cd and Zn regulation in response to an increase in ambient concentrations. Uptake rate constants were highest for Ag, followed by Zn > Co > Cd > Se. By incorporating metal influx from both the dissolved and particulate (sediment) phases, a bioenergetic-based kinetic model indicates that most (>98%) of the Cd, Co, Se and Zn in polychaetes arises from sediment ingestion due to the high ingestion rates of these animals and the low uptake rate of metals from the dissolved phase (porewater or overlying water). For Ag, approximately 5 to 35% is due to uptake from the dissolved phase. Our study suggests that the establishment of sediment quality criteria must consider sediment as a potentially important source for metal uptake in benthic invertebrates.>
4783. Nystrom,M; Nordemar,I; Tedengren,M (2001): Simultaneous and sequential stress from increased temperature and copper on the metabolism of the hermatypic coral Porites cylindrica. Marine Biology (Berlin) 138, 1225-1231.
<Stressors arising from human activities may interact not only with each other, but also with natural disturbances. However, experimental studies on disturbance complexity and physiological responses of corals to sublethal stresses, especially those due to human activities, are surprisingly few. In this study we investigated the stress response of the scleractinian coral Porites cylindrica after 24 h of exposure to copper (11 mug Cu l-1) and increased temperature (following a 4degreeC above-ambient curve), separately and in combination. We also investigated the effect of sequential stress where corals pre-exposed to increased temperature for 24 h were exposed to copper (for 24 h) after a 5-day recovery period. Changes in gross primary production (Pg: per milligram chlorophyll a per hour) and respiration (R
er square centimeter per hour) in terms of dissolved oxygen were used as indicators of stress. The results show that heat and the combination of heat and copper significantly reduced production rate. However, corals exposed to elevated temperature displayed a significantly higher production rate following the 5-day recovery period. The combination of the two stressors showed no additive or synergistic effects. Copper alone had no effect on the production rate. However, corals that were pre-exposed to increased temperature and again exposed to copper after 5 days displayed a significant reduction in production rate. The respiration rate was significantly reduced by all treatments, although no significant differences between treatments were detected. The results presented here illustrate how a stressor that does not affect corals when acting in isolation may do so in sequential combination with other stressors>
4929. Reichelt-Brushett,AJ; Harrison,PL (2000): The effect of copper on the settlement success of larvae from the scleractinian coral Acropora tenuis. Marine Pollution Bulletin 41, 385-391.
<This study examined the effect of copper on the settlement success of planula larvae of the reef-building coral Acropora tenuis during 1994 and 1996 at Magnetic Island, Great Barrier Reef. Copper concentrations of 2, 10, 20 mug l-1 did not inhibit larval settlement after 48-h exposure. However, copper concentrations of 42 mug l-1 and 81 mug l-1 significantly reduced settlement success of A. tenuis larvae after 48-h exposure compared with controls using normal seawater. At 200 mug l-1 copper, all larvae died. EC50 values for the effect of copper on A. tennis larval settlement were calculated from the 1996 results using measured copper concentrations. The 48-h EC50 was 35 mug l-1 with an upper and lower 95% confidence limit of 37 mug l-1 and 32 mug l-1, respectively. The 48-h NOEC value for both experiments was 20 mug l-1 copper. These experiments provide some of the first data on sub-lethal effects of trace metals on tropical marine organisms, and demonstrate that relatively low copper concentrations impair or inhibit settlement of coral larvae.>
