Hepatic Element Concentrations of Lesser Scaup (<Emphasis Type="Italic">Aythya affinis</Emphasis>) During Spring Migration in the Upper Midwest

High concentrations of some hepatic elements might be contributing to the decline of the continental lesser scaup (Aythya affinis) population. We evaluated hepatic element concentrations of male and female lesser scaup collected from the upper Midwest (Iowa, Minnesota, North Dakota, and South Dakota) during the 2003 and 2004 spring migrations. We measured concentrations of 24 elements in livers of 117 lesser scaup. We found that only selenium concentrations were at levels (>3.0 μg/g wet weight [ww)]) proposed to adversely affect reproduction. Approximately 49% of females (n = 61) had individual hepatic concentrations >3.0 μg/g ww selenium (Se). Our observed hepatic concentration of Se was similar to that reported in lesser scaup collected from the mid-continental United States but less than Se concentrations reported from the Great Lakes region. We found that the liver cadmium (Cd) concentration for males was significantly higher than that for females. Gender differences in hepatic Cd concentrations have not been previously reported for lesser scaup, but Cd is known to have negative impacts on male reproduction. Our results indicate that lesser scaup migrating through the upper Midwest in spring have elevated Se levels and that males carry a significantly greater Cd burden than females. Moreover, elemental concentrations might be high enough to affect reproduction in both male and female lesser scaup, but controlled laboratory studies are needed to adequately assess the effects of Se and Cd on lesser scaup reproduction.     

Selenium Concentrations in Greater Scaup and Dreissenid Mussels During Winter on Western Lake Ontario

One hypothesis for the decline of the North American greater (Aythya marila) and lesser (A. affinis) scaup population is that contaminant burdens acquired on wintering or staging areas impair reproduction or cause lethal or sublethal health effects. Recent studies have found increased selenium (Se) concentrations in scaup but have focused on the fall and spring staging periods. From January to March 2006 and December to March 2006 and 2007, we analyzed liver tissues collected from greater scaup wintering in western Lake Ontario for 16 trace elements. We also measured Se concentrations in greater scaup blood and Dreissenid mussel tissue. Se was the only trace element that occurred at increased concentrations (>10 μg/g liver dry weight) in a substantial proportion (99%) of greater scaup livers. We also found that hepatic Se concentrations increased throughout winter and were increased in nearly all birds from January to March, suggesting that accumulation of this trace element occurred soon after their arrival in fall. Se concentrations were similar in male and female birds, but juvenile birds had higher concentrations than did adults. Blood Se concentrations were correlated to liver Se concentrations in 2006 only, suggesting that blood Se concentration is an unreliable predictor of liver concentration. Se in Dreissenid mussels generally decreased with mussel size and did not change throughout winter. Overall, our results suggest that greater scaup wintering on western Lake Ontario acquire sufficiently high Se concentrations to potentially impact their health. Thus, several indicators of health and survival should be examined in relation to Se concentrations in wintering scaup.     

Metal Analysis of Scales Taken from Arctic Grayling

This study examined concentrations of metals in fish scales taken from Arctic grayling using laser ablation–inductively coupled plasma mass spectrometry (LA-ICPMS). The purpose was to assess whether scale metal concentrations reflected whole muscle metal concentrations and whether the spatial distribution of metals within an individual scale varied among the growth annuli of the scales. Ten elements (Mg, Ca, Ni, Zn, As, Se, Cd, Sb, Hg, and Pb) were measured in 10 to 16 ablation sites (5 μm radius) on each scale sample from Arctic grayling (Thymallus arcticus) (n = 10 fish). Ca, Mg, and Zn were at physiological levels in all scale samples. Se, Hg, and As were also detected in all scale samples. Only Cd was below detection limits of the LA-ICPMS for all samples, but some of the samples were below detection limits for Sb, Pb, and Ni. The mean scale concentrations for Se, Hg, and Pb were not significantly different from the muscle concentrations and individual fish values were within fourfold of each other. Cd was not detected in either muscle or scale tissue, whereas Sb was detected at low levels in some scale samples but not in any of the muscle samples. Similarly, As was detected in all scale samples but not in muscle, and Ni was detected almost all scale samples but only in one of the muscle samples. Therefore, there were good qualitative and quantitative agreements between the metal concentrations in scale and muscle tissues, with LA-ICPMS analysis of scales appearing to be a more sensitive method of detecting the body burden of Ni and As when compared with muscle tissue. Correlation analyses, performed for Pb, Hg, and Se concentrations, revealed that the scale concentrations for these three metals generally exceeded those of the muscle at low muscle concentrations. The LA-ICPMS analysis of scales had the capability to resolve significant spatial differences in metal concentrations within a fish scale. We conclude that metal analysis of fish scales using LA-ICPMS shows considerable promise as a nonlethal analytical tool to assess metal body burden in fish that could possibly generate a historic record of metal exposure. However, comprehensive validation experiments are still needed. Received: 8 March 2000/Accepted: 31 May 2000     

Concentrations of Heavy Metals in American Woodcock Harvested in Connecticut

The American woodcock is an important migratory species to both consumptive and nonconsumptive users throughout the species range. Woodcock populations have been declining steadily since surveys began in 1968. Laboratory and field studies have demonstrated several adverse effects associated with metals in other species, which has led to their inclusion as potential contributing factors to the woodcock population decline. We investigated the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), and selenium (Se) in pectoral muscle (n = 100), livers (n = 108), and kidneys (n = 104) and Pb in wing bones (n = 53) from woodcock harvested in Connecticut. Cd concentrations were elevated in 99% of woodcock livers and kidneys; 30% of kidneys were above 100 μg/g dry weight, a Cd level of reported adverse tissue and reproductive effects in other species. Hg and Cr concentrations were below current biologically significant thresholds. Asc, Pb, and Se in soft tissues were associated with lead shot use in collection. Se in 24% of livers was above 10 μg/g dry weight, the reported threshold for avian health. Wing-bone Pb was elevated above 20 μg/g in 61% of adults and 23% of juveniles examined. Our findings indicate that woodcock are being exposed to potentially damaging levels of at least two metals with known effects in other species.     

Pulmonary metal distribution in urban dwellers

To clarify the factors influencing the concentrations and distribution of metal elements in the lung, we analyzed the following 8 metals in the 5 lung lobes of 17 autopsied urban dwellers by flame or flameless atomic absorption spectrometry: aluminum (Al), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), manganese (Mn), copper (Cu), and Zinc (Zn). The arithmetic mean value (in micrograms of metal per gram of dry weight) calculated for five lobar metal concentrations in each subject ranged from 80 to 681 for Al, from 0.34 to 3.41 for Cd, from 0.41 to 12.7 for Cr, from 0.22 to 1.93 for Ni, from 0.15 to 1.47 for Pb, from 0.64 to 2.36 for Mn, from 2.84 to 7.24 for Cu, and from 40.7 to 77.6 for Zn. The eight metals were classifiable into two groups on the basis of the interindividual and interlobar concentration variations. The first group, consisting of Cu and Zn, was characterized by smaller interindividual variations (coefficient of variation, CV < 30%) and smaller inter lobar variations (mean CV < 15%). Their levels were not affected significantly by sex, smoking habits, or possible occupational exposure to metal-containing dust. In contrast, the second group, consisting of Al, Cd, Cr, Ni, Pb, and Mn, exhibited larger interindividual variations (CV > 45%) and larger interlobar variations (mean CV > 25%). Concentrations of these metals, except for Cd, tended to be higher in the upper lobes than in the lower lobes. The concentrations of Al and Cr were significantly higher in men than in women. Smoking significantly elevated the levels of Cr, Cd, Ni, and Pb, and the concentrations of Al, Cr, Ni, and Mn were higher in subjects with possible occupational exposure to metal-containing dust than in those without such exposure. However, the interlobar distribution patterns of the metals did not seem to be influenced by sex, smoking habits, or occupational exposure to metal-containing dust. Received: 18 March 1996 / Accepted: 2 January 1997     

Contaminants in Lesser and Greater Scaup Staging on the Lower Great Lakes

The decrease and subsequent lack of recovery of the North American scaup population has increased concerns about contaminants acquired during migration. We collected 189 fall- and spring-migrant lesser (Aythya affinis) and greater scaup (A. marila) on the lower Great Lakes (LGL) to determine if organic contaminants and trace elements in scaup livers were increased and to evaluate sources of variation in selenium (Se) burdens. We found that all organic contaminants were below toxic levels. Of 18 trace elements, only Se was detected at increased (>10-ppm dry-mass) levels. Se in lesser scaup increased but remained constant in greater scaup throughout fall; levels were increased in 14% of lesser scaup and 46% of greater scaup. During spring, Se increased in lesser scaup but decreased slightly in greater scaup; levels were increased in 75% of lesser scaup and 93% of greater scaup. We suggest that Se may be problematic for some breeding female scaup after departing the LGL, but more research is needed to determine the extent to which it affects scaup demographics.     

Seasonal Dynamics of Dissolved Metals in Surface Coastal Waters of Southwest India

Spatial and temporal variations in concentration of dissolved metals viz. Copper (Cu), Lead (Pb), Chromium (Cr), Nickel (Ni), Zinc (Zn), Cadmium (Cd) and Mercury (Hg) in surface waters of southwest coast of India were studied. Concentrations of metals showed an aberration both temporally and spatially. Seasonal average concentrations of the analyzed metals followed the order Zn > Ni > Cu > Pb > Cd > Cr > Hg. The degree of contamination due to metal was determined by comparison with coastal water quality criteria. It established enrichment of Cu, Zn, Ni and Hg due to anthropogenic influence along southwest coast of India.     

Lethality Toxicities Induced by Metal Exposure During Development in Nematode <Emphasis Type="Italic">Caenorhabditis Elegans</Emphasis>

Lethality changes were investigated during development in 4 h metal exposed Caenorhabditis elegans. Exposure to examined metals caused severe lethality toxicities in L1- and L2-larvae, in L3-larvae exposed to examined metals at concentrations of 50 and 100 μM and to Pb, Hg, and Cr at the concentration of 2.5 μM, in L4-larvae exposed to examined metals at concentrations of 50 and 100 μM, and in adults exposed to Pb, Hg, and Cr at the concentration of 100 μM. Moreover, the lethality toxicities induced by Pb and Hg in L1 larvae for 4 h could be largely comparable to those in young adults for 24 h.     

Heavy Metals Bioaccumulation in Tissues of Spiny-Cheek Crayfish (<Emphasis Type="Italic">Orconectes limosus</Emphasis>) from Lake Gopło: Effect of Age and Sex

The aim of the present work was to assess the concentrations of metals in the abdominal muscle and exoskeleton of 3-year-old males and 4-year-old females and males of spiny-cheek crayfish (Orconectes limosus) collected from Lake Gop?o. A total of 93 males and 35 females were collected in autumn (October 2014). The analyzes of heavy metals were conducted by means of atomic absorption spectroscopy with a PU9100X spectrometer. The content of mercury was determined using AMA 254 mercury analyser. As analyses indicated heavy metals accumulated in the muscle and exoskeleton in the following sequence: Zn?>?Cu?>?Pb?>?Mn?>?Ni?>?Hg and Mn?>?Pb?>?Zn?>?Ni?>?Cu?>?Hg, respectively. Statistically significant differences between 3- and 4-year-old males were found for all analyzed metals. Gender dependent differences were calculated only for Ni in the muscle tissue and for Mn and Hg in the exoskeleton. In comparison with the study carried out 2 years ago notably higher concentrations of Pb were found in the muscle and a higher content of Zn, Pb, Mn and Ni was determined in the exoskeleton.     

Metals in Laysan Albatrosses from Midway Atoll

We examined the concentrations of lead, cadmium, selenium, chromium, manganese, arsenic, tin, and mercury in the heart, liver, kidney, salt gland, and feathers of adult (n = 10) and young (n = 15) Laysan albatrosses (Diomedea immutabilis) from Midway Atoll in the north-central Pacific Ocean. Lead poisoning has been reported in some Laysans nesting near buildings on Midway, but other heavy metals have not been examined. We examined tissue distribution of metals by age and gender (adults only). We also examined tissue concentrations in three birds with a droop-wing syndrome characteristic of lead poisoning. We compared metal levels in salt gland (a special excretory organ of marine birds) with those in other tissues. All metals varied significantly across tissues in both adults and chicks, and the relative tissue concentrations were similar in adults and chicks for most metals. Adults had higher levels of most metals in most organs, with significant differences mainly for cadmium (up to 20× higher in kidney and salt gland) and for mercury (17× higher in kidney). However, chicks had significantly higher manganese in liver and arsenic in salt gland. The salt gland had concentrations of most metals (except cadmium, selenium, and mercury) comparable to the kidney levels, which is consistent with it serving as an excretory organ for the cations. Chicks with droop-wings had very elevated levels of lead in their tissue (16.8 ppm in feathers, 14 ppm in liver and kidney), whereas levels of other metals were not significantly different from the apparently normal chicks. Received: 1 April 1999/Accepted: 29 June 1999     

Decennary Variations of Dissolved Heavy Metals in Seawater of Bohai Bay,North China

Characteristics of the spatial and temporal distributions of selected dissolved heavy metals (Cu, Zn, Pb, Hg and Cd) in Bohai Bay, north China was investigated. Water samples from 22 sites were collected and analyzed for the selected metals with atomic absorption spectrometry from the year of 1996 to 2005. Relatively high concentrations of Cu, Zn, Pb and Hg were detected, with maximum concentrations in the 10-year period of 16.30, 422.00, 40.40, 0.23 μg/L respectively. The concentrations of Cd in all samples were quite low, with maximum level of 0.89 μg/L. The spatial distribution of dissolved Cu, Zn and Pb was analogous, where their average concentrations generally descended from the coastline to the central areas of the bay. Differently, for Hg and Cd, relatively high concentrations occurred not only in inshore but also in offshore areas. Measured data of heavy metals were compared with sea water quality standard of China (SWQSC). Cd concentrations in all samples were below SWQSC Grade-I. The percentages of Cu, Zn, Pb, and Hg at Grade-III levels in Bohai Bay were 2.67%, 30.00%, 30.43% and 0.36%, respectively, suggesting the severe contamination of Zn and Pb in this area. Terrestrial inputs via different rivers and sewages may be the important source for the heavy metals contamination.     

Comparison of Metal Accumulation in Fish Species from the Southeastern Black Sea

In this study, it was aimed to determine accumulation of the metal concentrations in fish species in different regions which are Sürmene and Yomra bay at southeastern Black sea in Trabzon-Turkey. For this purpose, concentrations of metals (Cr, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Hg, Pb) were measured by inductively coupled plasma mass spectrometry (ICP-MS) in muscle of red mullet (Mullus barbatus ponticus) and whiting (Merlangius merlangus euxinus). Metal concentrations were found for whiting ranged as follows; 0.35–1.64 (Cr), 0.01–0.09 (Co), 0.01–0.71 (Ni), 0.71–1.45 (Cu), 18.64–68.06 (Zn), 2.05–9.66 (As), 0.15–14.16 (Se), 0.01–0.22 (Cd), 0.01–0.01 (Sb), 0.01–0.15 (Hg), 0.01–0.25 (Pb) and for red mullet as 0.43–1.04 (Cr), 0.05–0.23 (Co), 0.02–0.67 (Ni), 0.74–2.32 (Cu), 19.89–43.50 (Zn), 6.04–24.82 (As), 0.02–9.83 (Se), 0.01–0.11 (Cd), 0.01–0.01 (Sb), 0.07–0.18 (Hg), 0.01–0.20 (Pb) μg g⁻¹ dry weight. Metal concentrations in samples were found to be lower than legal limits proposed by Turkish Food Codex (2008), Food and Agricultural Organization (1983), and European Commission (Off J Eur Union L364-5–L364-24, 2006) for human consumption.     

Toxic Element Concentrations in the Bottlenose (<Emphasis Type="Italic">Tursiops truncatus</Emphasis>), Striped (<Emphasis Type="Italic">Stenella coeruleoalba</Emphasis>) and Risso’s (<Emphasis Type="Italic">Grampus griseus</Emphasis>) Dolphins Stranded in Eastern Adriatic Sea

Concentrations of cadmium (Cd), arsenic (As), mercury (Hg) and lead (Pb) were measured in muscle, liver and kidney of three cetacean species, the bottlenose (Tursiops truncatus), striped (Stenella coeruleoalba) and Risso’s (Grampus griseus) dolphins from the Croatian waters of the Adriatic Sea. In all three dolphin species Cd levels decreased in tissues in the order: kidney > liver > muscle, while As and Pb decreased in the order: liver > kidney > muscle for striped and Risso’s dolphins, but with the order reversed for liver and kidney in the bottlenose dolphin for Pb. Levels of Hg consistently followed the order: liver > muscle > kidney, with mean concentrations in the liver being 11–34 times higher than in the other tissues. The highest mean concentrations of trace elements were measured in Risso’s dolphins at 14.9 μg/g wet weight, for Cd in the kidney, and concentrations in the liver of 2.41, 1,115 and 0.63 μg/g for As, Hg and Pb, respectively. Statistically significant differences between the three dolphin species were determined for Cd, Hg and Pb in liver tissues, for As in muscle and for Cd in kidney. Significant correlations of metals between tissues were determined in all three species. The results presented give an indication of the environmental condition with regard to the content of toxic metals along the eastern coast of the Adriatic Sea.     

Assessment of Metal Concentrations in Sediments from Lake Bafa (Western Anatolia): An Index Analysis Approach

Metals, organic carbon contents were determined in surficial and core sediment samples from Lake Bafa, Western Anatolia in 2010. The ranges of Fe, Mn, Pb, Cu, Ni, Cr, Zn and Hg contents of sediments from the Bafa Lake were 9.4–35 gkg⁻¹, 250–780, 2.3–20, 5.8–55, 1.2–480, 63–278, 26.6–79.9 and 0.013–0.273 mg kg⁻¹, respectively. The mean metal concentrations in surficial sediments obtained in this study decreased in the following order; Fe > Mn > Ni > Cr > Zn > Cu > Pb > Hg for Bafa lake. Total organic carbon concentrations of the bottom sediments from the Bafa Lake varied between 0.35 % and 3.58 %. The mean concentrations of metal were lower than the background levels in earth crust except Cr and Ni in the core sediments. The metal levels were evaluated according to the New Geo-accumulation Index, enrichment and contamination factors. The results confirmed that the Bafa Lake is not facing serious environmental pollution risk due to metal contamination except Hg. The levels of Cr, Ni, Cu, Fe, Zn and Mn generally appear to be uniformly distributed with depth except Hg and Pb due to anthropogenic sources in the core sediments.     

Biomagnification of Trace Elements in the Aquatic Food Web in the Mekong Delta,South Vietnam Using Stable Carbon and Nitrogen Isotope Analysis

In the present study, we report the concentrations of 21 trace elements (V, Cr, Mn, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sn, Sb, Cs, Ba, Hg, Tl, Pb, and Bi), as well as the results of the analysis of stable carbon and nitrogen isotopes, of the various biota that make up the food web in the main stream of the Mekong Delta near Can Tho, South Vietnam. A significant trophic level-dependent increase was found in concentrations of Se, Rb, and Hg with increasing δ¹⁵N, indicating that an overall biomagnification of these elements occurred. However, the increase of Hg concentration per trophic level was lower than in previous studies. In contrast, the concentration of Mn showed an opposite trend in the food web of the Mekong Delta. In addition to these overall trends, the present study revealed that the biomagnification profiles of trace metals differ between crustaceans and fishes; concentrations of Mn, Cu, Zn, As, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, and Pb were significantly higher in crustaceans, whereas fishes showed higher concentrations of Cr, Rb, and Hg (trophic level determined by δ¹⁵N). The differences in the biomagnification profile between the major taxa might be attributed to differences in metal accumulation and in detoxification abilities such as possessing a metal-binding protein, e.g., metallothionein (MT).     

Hepatic Concentrations of Inorganic Contaminants and Their Relationships with Nutrient Reserves in Autumn-Migrant Common Loons at Lake Erie

Common loons (Gavia immer) are piscivorous, high–trophic level feeders that bioaccumulate inorganic contaminants at concentrations that can negatively impact their health and reproduction. Concentrations of inorganic contaminants, especially mercury (Hg), in blood, organs, and muscle have been quantified in common loons on breeding grounds, but these data are limited for migrating loons. We investigated sex- and age-related hepatic concentrations of inorganic contaminants in common loons (n = 53) that died from botulism and were salvaged at a Great Lakes staging area (i.e., Long Point, Lake Erie) during November 2005. We also investigated if hepatic concentrations of inorganic contaminants influenced lipid, protein, and mineral in our sample of migrant common loons. Last, we determined if there was correlation between Hg and selenium (Se). Consistent with data from breeding grounds, mean concentrations of Hg in liver were approximately 2.5 times greater in adult ([`(x)] \bar{x}  = 14.64 ± 16.69 μg g<sup>−1</sup>) compared with juvenile birds ([`(x)] \bar{x}  = 3.99 ± 2.27 μg g⁻¹). Elements detected in liver at potentially harmful levels were Hg and Se, of which lipid reserves varied negatively with Hg concentrations but positively with Se concentrations. In addition, Hg and Se were correlated (r = 0.65) at greater then a demethylation threshold (total Hg ≥ 8.5 μg g⁻¹ dw) but not lower than that. Concentrations of inorganic contaminants did not influence protein and mineral levels in our sample of common loons. Our results suggest that Hg accumulation negatively affects lipid levels in migrant common loons. Results are also consistent with a nontoxic Hg–Se protein complex protecting loons migrating through areas that are relatively Se rich. Although the acquisition of Se during the nonbreeding season may decrease the toxicity of Hg, future research should consider the synergistic Hg–Se effect on reproduction in common loons that migrate through Se-rich locales, such as the Great Lakes.     

Concentrations of Metals Associated with Mining Waste in Sediments, Biofilm, Benthic Macroinvertebrates, and Fish from the Coeur d'Alene River Basin, Idaho

Arsenic, Cd, Cu, Pb, Hg, and Zn were measured in sediments, biofilm, benthic macroinvertebrates, and fish from the Coeur d'Alene (CDA) River to characterize the pathway of metals transfer between these components. Metals enter the CDA Basin via tributaries where mining activities have occurred. In general, the ranking of food-web components from the greatest to smallest concentrations of metals was as follows: biofilm (the layer of abiotic and biotic material on rock surfaces) and sediments > invertebrates > whole fish. Elevated Pb was documented in invertebrates, and elevated Cd and Zn were documented in sediment and biofilm approximately 80 km downstream to the Spokane River. The accumulation of metals in invertebrates was dependent on functional feeding group and shredders-scrapers that feed on biofilm accumulated the largest concentrations of metals. Although the absolute concentrations of metals were the largest in biofilm and sediments, the metals have accumulated in fish approximately 50 km downstream from Kellogg, near the town of Harrison. While metals do not biomagnify between trophic levels, the metals in the CDA Basin are bioavailable and do biotransfer. Trout less than 100 mm long feed exclusively on small invertebrates, and small invertebrates accumulate greater concentrations of metals than large invertebrates. Therefore, early-lifestage fish may be exposed to a larger dose of metals than adults. Received: 3 April 1997/Accepted: 8 September 1997     

Levels of Cd, Pb, As, Hg, and Se in Hair of Residents Living in Villages Around Fenghuang Polymetallic Mine, Southwestern China

Heavy metal levels in hair of residents living in villages around Fenghuang mine were investigated. Samples belonging to mine areas showed the highest values, with mean concentrations (mg kg⁻¹) of 0.17 for Cd, 8.67 for Pb, 0.11 for As, 2.19 for Hg, and 0.64 for Se. Significant correlations (p < 0.01) were found between Cd–Pb, Cd–As, Pb–As, and Se–Hg. There is no significant difference in any of the elements among age groups. However, significant differences in Cd and Pb levels were found between genders. Results revealed that children and females were more susceptible to Cd and Pb exposure.     

Trace metal concentrations in edible tissue of snapper, flathead, lobster, and abalone from coastal waters of Victoria, Australia

The concentrations of heavy metals in the edible tissue of commonly fished species of the Victorian coast of Australia are reported. The metals studied were As, Cd, Cu, Hg, Pb, Se, and Zn and the fish species examined were snapper (Pagruss auratus), flathead (Platycephalus bassenssis and Neoplatycephalus richardsoni), lobster (Jasus edwardsii), and abalone (Haliotis rubra). None of the fish species studied had average concentrations exceeding the maximum levels specified for As, Cd, Hg, and Pb by the Food Standards Australia and New Zealand Food Standards code. Additionally, the concentrations of Cu, Se, and Zn were close to or below the median values generally expected in these species. Essential trace elements Se and Zn were found to be well regulated by all fish species. Although also essential, Cu was not so well regulated, especially in abalone. Nonessential metals As, Cd, and Hg are not regulated in the studied fish and their concentrations in the fish tissue are dependent on size and fishing zone. Metal concentrations were not largely affected by sex. Surprisingly, the concentrations of metals in fish in Port Phillip Bay, a zone, which includes the major cities of Melbourne and Geelong and is known to have high concentrations of metals in the water and sediment, were not consistently higher than those in other less-populated fishing zones.     

Contaminant Loading in Drainage and Fresh Water Used for Wetland Management at Stillwater National Wildlife Refuge

Throughout the western United States, studies have identified various detrimental effects of contaminants to aquatic biota from the use of agricultural drainage water for management of arid wetlands. However, little is known about the relative contributions of contaminant loading from pollutants dissolved in water compared with those carried by drifting material (e.g., detritus) associated with drainage water. Consequently, we determined loading rates for contaminants dissolved in water and those incorporated by drifting material for drainage (Diagonal Drain) as well as fresh (S-Line Canal) water used for wetland management at Stillwater National Wildlife Refuge (SNWR), Nevada during the early, middle, and late periods of the irrigation season (June through mid-November) in 1993. We found loading rates for trace elements throughout the irrigation season were almost entirely (> 98%) associated with contaminants dissolved in the water rather than incorporated by drift. Although drift contributed little to the total loading for trace elements to SNWR wetlands, contaminant concentrations were much greater in drift compared with those dissolved in water. Loading rates for dissolved As, B, Hg, and total dissolved solids (TDS) differed among periods for the Diagonal Drain. Along the Diagonal Drain, loading rates for dissolved As, B, Hg, Mo, unionized ammonia (NH₃-N), TDS, and Zn differed among its three sampling sites. B was the only trace element with differences in loading rates for drift among periods from the Diagonal Drain. In contrast, loading rates for As, B, Cr, Cu, Hg, Se, and Zn in drift differed among periods for the S-Line Canal. Along Diagonal Drain, loading rates in drift for B (middle and late periods), Cr, Cu, and Zn differed among sites. Hg (xˉ ≥ 12.0 ng/L) and NH₃-N (xˉ ≥ 0.985 mg/L) dissolved in water as well as B (xˉ ≥ 97.4 μg/g DW) and Hg (xˉ ≥ 0.461 μg/g DW) in drift from the Diagonal Drain and S-Line Canal exceeded screening levels (SLs) for protection of aquatic biota throughout the irrigation season. Dissolved As (xˉ ≥ 0.0426 mg/L) in water from the Diagonal Drain during all periods exceeded the SL for protection of aquatic biota. Dissolved B (xˉ = 1.03 mg/L) in water from the Diagonal Drain during the early period exceeded the SL for protection of aquatic biota. Received: 18 September 1997/Accepted: 5 February 1998