Feeding and Growth Responses of the Snail <Emphasis Type="Italic">Theba pisana</Emphasis> to Dietary Metal Exposure

The effects of dietary exposure to copper (Cu), lead (Pb), and zinc (Zn) on feeding activities, growth response, and mortality of Theba pisana snails were studied in 5-week feeding tests. Snails were fed on an artificial diet containing the following Cu, Pb, or Zn concentrations: 0, 50, 100, 500, 1000, 5000, 10,000, and 15,000 μg/g dry food. At the end of 5 weeks, the food consumption rate was decreased with increasinges in both metal concentrations and time of exposure. The estimated concentrations of metals that reduces food consumption to 50% (EC₅₀) after 5 weeks were 56, 118, and 18 μg/g dry food for Cu, Pb, and Zn, respectively. All tested metals in the diet were found to inhibit growth of the snails in a dose-dependent manner. The toxic effect on growth of the tested metals could be arranged in the order Cu > Zn > Pb. The cumulative percentage mortality among snails fed a Cu- or Zn-contaminated diet was 73.3% and the respective value for a Pb-contaminated diet was 13.3%. There was a positive correlation between growth coefficient and food consumption for all tested metals.     

The Effect of pH on the Uptake and Toxicity of Copper and Zinc in a Tropical Freshwater Alga (Chlorella sp.)

Copper and zinc toxicity to the freshwater alga Chlorella sp. was determined at a range of pH values (5.5–8.0) in a synthetic softwater (hardness 40–48 mg CaCO₃/L). The effects of the metals on algal growth (cell division) rate were determined after 48-h exposure at pH 5.5, 6.0, 6.5, 7.0, 7.5, and 8.0. The toxicity of both metals was pH dependent. As pH decreased from 8.0 to 5.5, the copper concentration required to inhibit the algal growth rate by 50% (IC50) increased from 1.0 to 19 μg/L. For zinc, the IC50 increased from 52 to 2700 μg/L over the same pH range. Changes in solution speciation alone did not explain the increased toxicity observed as the pH increased. Modelled Cu²⁺ and Zn²⁺ concentrations decreased with increasing pH, whereas toxicity was observed to increase. Measurements of extracellular (cell-bound) metal concentrations support the biotic ligand model (BLM) theory of competition between protons (H⁺) and metals for binding sites at the algal cell surface. Higher extracellular metal concentrations were observed at high pH, indicating reduced competition. Independent of pH, both extracellular and intracellular copper were directly related to growth inhibition in Chlorella sp., whereas zinc toxicity was related to cell-bound zinc only. These findings suggest that the algal cell surface may be considered as the biotic ligand in further development of a chronic BLM with microalgae. Conditional binding constants (log K) were determined experimentally (using measured intracellular metal concentrations) and theoretically (using concentration-response curves) for copper and zinc for Chlorella sp. at selected pH values. Excellent agreement was found indicating the possibility of using concentration-response data to estimate conditional metal-cell binding constants.     

Effect of Single and Paired Metal Inputs in Soil on a Stress-Inducible Transgenic Nematode

A toxicity test using a transgenic strain of the free-living soil nematode Caenorhabditis elegans carrying a stress-inducible β-galactosidase reporter has been adapted for use in soil biomonitoring. High concentrations (250 μg · g⁻¹) of cadmium are required to induce the stress response in worms exposed to Lufa 2.2 soil. Even at relatively high concentrations, the response to copper and zinc additions alone is minimal, yet combinations of cadmium and copper in the test soil induce a larger response than with cadmium alone at the same concentration. In contrast, the addition of both zinc and cadmium induces a lower response than cadmium additions alone. Analysis of the interstitial water suggests that there is preferential occupation by copper of sorption sites in the soil, allowing more cadmium to remain in solution. Conversely, cadmium and zinc would appear to interact similarly with the soil constituents, resulting in an increase of both metals in solution with increased additions to the soil. Aquatic tests mimic the results of the soil test, so it is not increased cadmium availability alone that causes an increased stress response when both cadmium and copper are present. The presence of other metals could reduce the amount of cadmium available, which may be one factor in the zinc moderation of the stress response to cadmium. Intracellular mechanisms may also contribute to the copper enhancement of the stress response to cadmium. Received: 30 November 1998/Accepted: 12 May 1999     

Mortality, Preference, Avoidance, and Activity of a Predatory Leech Exposed to Cadmium

The effects of cadmium on the hatching success of the cocoons of the freshwater predatory leech Nephelopsis obscura were examined together with the survivorship of hatchlings, changes in 96-h LC₅₀ with biomass, preference-avoidance responses and changes in activity. The 96-h EC₅₀ for cocoons was 832.6 μg Cd/L with a decreasing bounded monotonic function best describing hatchling success as a function of Cd concentration. Exposure of cocoons to Cd had a highly significant effect on post-hatchling survivorship with survivorship of hatchlings from the 0–500-μg Cd/L concentrations not significantly different from each other but higher than survivorship of hatchlings from cocoons exposed to 1,000–4,000 μg Cd/L. Resistance to acute Cd toxicity, measured as LC₅₀, increased with leech biomass. In preference-avoidance tests large leeches (>450 mg) spent more time in 100- and 200-μg Cd/L than in control water or in 50-μg Cd/L, while small leeches (<250 mg) spent more time in 200-μg Cd/L compared to control water or 50–100-μg Cd/L. Leeches exposed to 100- and 200-μg Cd/L exhibited a significant decrease in activity compared to the leeches in the control and 50-μg Cd/L treatments. Received: 14 February 1996/Revised 24 June 1996     

Cadmium Toxicity and Uptake by Mats of the Freshwater Diatom: <Emphasis Type="Italic">Navicula pelliculosa</Emphasis> (Bréb) Hilse

Contaminant uptake by algae, and its subsequent toxicity, has important ramifications for aquatic biomonitoring and environmental risk assessment. To study the effects of cadmium on diatom mats, a series of experiments was undertaken. These investigated the sensitivity of Navicula pelliculosa mats to cadmium, uptake of cadmium across a range of exposure concentrations, influence of mat biomass and thickness on uptake, and cadmium uptake by mats over time. Diatom mat formation proved to be sensitive to cadmium exposure, with a 96-h EC₅₀ of 31 μg/L. The rapid uptake of cadmium over 15 min was a linear function of exposure concentration and was not significantly affected by mat thickness. Cadmium uptake over time was also a linear function of exposure concentration for time periods up to 5 h. Linear uptake was likely due to the availability of algal binding sites as cadmium ions diffused through the diatom mats. Internal high-pH microenvironments may also have influenced uptake, through cadmium precipitation or enhanced adsorption within the mats. The lack of a significant relationship between mat biomass and uptake could be explained by the static water exposure conditions. Other studies have shown that cadmium uptake by algal mats was only significantly affected by biomass under flowing water conditions. Flowing water appeared to facilitate the diffusion of cadmium ions through the algal mats. Our research demonstrates the propensity of diatom mats to adsorb cadmium to achieve concentrations that could inhibit macroinvertebrate grazing. Overall, these findings contribute to a greater understanding of cadmium bioavailability in aquatic ecosystems and to the further development of benthic algae as an effective biomonitoring tool.     

Determination of Metal Levels in Thirteen Fish Species from Lakshadweep Sea

A bio-monitoring study was performed to investigate the concentration of certain metals (cadmium, cobalt, copper, iron, magnesium, manganese, nickel, lead and zinc) in gill, skin and muscle of thirteen demersal fish species of Agatti Coast of Lakshadweep Sea. All the metal concentrations in gill are higher than skin and muscle. Concentrations of toxic metals such as Cd (0.61 ± 0.67 μg g⁻¹ in Gerres longirostris), Mn (0.83 ± 1.21 μg g⁻¹ in Lutjanus fulvus) and Ni (0.56 ± 0.83 μg g⁻¹ in L. bengalensis) were well above the permissible limits suggested by World Health Organization and Food and Agricultural Organizations.     

Effects of Copper, Cadmium, and Zinc on the Hatching Success of Brine Shrimp (Artemia franciscana)

Previous studies indicate that the hatching success of brine shrimp (Artemia franciscana) cysts is surprisingly sensitive to ambient metal concentrations. These studies estimated median effective concentrations (EC₅₀s) of 7, 5, and 28 μg l⁻¹ for Cd, Cu, and Zn, suggesting that the hatching end point for A. franciscana is the most sensitive tested to date for Cd and Zn in saline environments and comparable in sensitivity with the most sensitive tested to date for Cu. Furthermore, these data suggest that brine shrimp are at significant risk from Cu and Zn in Great Salt Lake (GSL), UT, where ambient concentrations as high as 10 and 14 μg l⁻¹, respectively, have been measured. Given that brine shrimp appear to be successfully reproducing in GSL, we hypothesized that these toxicity values were either biased low as a result of an artifact of the test method used or that site-specific water-quality conditions in the lake had decreased metal bioavailability such that brine shrimp could successfully reproduce. To test these hypotheses, we initiated a step-wise series of experiments. First we investigated the effects of pretreatment of brine shrimp cysts with antibiotics on brine shrimp sensitivity to metals because previous investigators as part of their test methods have used antibiotics. Next we considered the effect of ionic composition of the artificial test media on sensitivity. Finally, we evaluated the effects of the site-specific water quality of the GSL on metal bioavailability and toxicity. Results indicate that pretreatment of cysts with antibiotics had no effect on sensitivity. However, we were unable to repeat the previous values for Cd and Zn, obtaining EC₅₀s of 11,859 and 289 μg l⁻¹ for Cd and Zn, respectively. For Cu, however, we estimated an EC₅₀ of 12 μg l⁻¹, so we conducted further testing on the artificial media, adjusting the media composition to better reflect the Ca²⁺ and HCO ₃ ⁻ concentration of normal seawater. This increased the EC₅₀ to 28 μg l⁻¹. Finally we evaluated the toxicity of Cu in GSL water and obtained an EC₅₀ of 68 μg l⁻¹, suggesting that the increased dissolved organic carbon in GSL has a significant protective effect. Overall, the results of this study suggest that brine shrimp hatching success is not particularly sensitive to Cd and Zn, but it is sensitive to Cu. However, site-specific water-quality conditions ensure that brine shrimp cyst hatching success is not significantly affected by any of these metals at the normal background concentrations that occur in GSL (<15 μg l⁻¹).     

Investigation of Zinc,Copper, Lead and Cadmium Accumulation in the Tissues of <Emphasis Type="Italic">Sander lucioperca</Emphasis> (L., 1758) Living in Hirfanlı Dam Lake,Turkey

This study, some metals (zinc, copper, lead and cadmium) were analyzed in liver, muscle and gills of Sander lucioperca (Linnaeus, 1758) caught from the Hirfanlı Dam Lake in December 2007. The highest concentrations were found in liver (zinc:32.5 μg/g, lead:10.73 μg/g, copper:5.85 μg/g, cadmium:0.76 μg/g) of Sander lucioperca. It was seen that the accumulation of zinc, lead and cadmium primarily took place in liver followed by muscles and gills. It was observed that copper is mainly accumulated in liver followed by gill and mucsles.     

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 Metal Concentrations in Feathers of Korean Shorebirds

This study presents concentrations of zinc, manganese, copper, lead, and cadmium in the feather of five shorebird species from Yeongjong Island, Korea in the East Asian–Australian migration flyways. The objectives of this study were to determine levels of heavy metal concentrations in the feathers of shorebirds, to evaluate the pattern of heavy metal concentrations in the feather and the liver, and to examine the correlation between heavy metal concentrations in the feathers and livers. We hypothesized that difference of heavy metal concentrations will show by the breeding ground of shorebirds. Lead concentrations in dunlins (geomean = 14.8 μg/g wet weight) and great knots (20.8 μg/g wet weight) feathers were significantly higher than Terek sandpipers (3.32 μg/g wet weight); other metals were not different among shorebirds. Zinc, lead, and cadmium concentrations in the feather were correlated with the liver concentrations, but manganese and copper concentrations were not. Zinc, manganese, copper, lead, and cadmium concentrations in the feather from this study were within the range of earlier studies for wild birds, but cadmium concentrations in dunlins were higher than other studies. Because lead concentrations in livers and feathers of the Terek sandpiper were lower than in other shorebirds, we suggest that Terek sandpipers were exposed to lower lead concentrations than Kentish plovers, dunlins, and great knots on their breeding ground. An erratum to this article can be found at     

Evaluation of Bivalves as Bioindicators of Metal Pollution in Freshwater

The fresh water bivalves, Lamellidens corrianus, Lamellidens marginalis, and Indonaia caeruleus were exposed to chronic concentration of arsenic (0.1719 ppm), cadmium (0.1284 ppm), copper (0.033 ppm), lead (1.50 ppm), mercury (0.0443 ppm) and zinc (1.858 ppm) separately up to 30 days in laboratory. Dry weight of each animal was used to calculate metal concentrations (μg/g) and the metal body burden (μg/individual). It was observed that lead (1235.4 μg/g) and arsenic (37.9 μg/g) concentration were highest in Lamellidens corrianus, zinc (3,032.3 μg/g) was highest in Lamellidens marginalis, while mercury (5.87 μg/g), cadmium (142 μg/g) and copper (826.7 μg/g) was highest in Indonaia caeruleus.     

Contaminations of Metal in Tissues of Siberian Gull Larus heuglini: Gender, Age, and Tissue Differences

The objective of the present study was to investigate the levels of metals, namely cadmium, lead, and zinc, in Siberian gull (Larus heuglini) (n = 15), in order to: (1) examine the sex and gender related variation in trace metal accumulation, and (2) to determine the significant between metal concentrations in the kidney, liver, and pectoral muscle. The concentrations were different between the tissues of bird as well as among the interaction (sex × age), but this difference (except cadmium in liver and zinc in kidney) between the gender (male and female) and age (adult and juvenile) didn’t exist. Results showed that the metal concentrations in the Siberian gull were decreased in sequence of kidney > liver > muscle. The cadmium, lead, zinc concentration overall means they were measured as 2.2 ± 0.7, 8.8 ± 2.5, and 91.1 ± 37. 1 μg/g for kidney, 1.1 ± 0.2, 5.1 ± 0.8, and 68.3 ± 27.8 μg/g for liver, and 0.8 ± 0.1, 3.4 ± 0.6, and 34.4 ± 23.2 μg/g for pectoral muscle, respectively.     

Toxicity of cadmium and zinc mixtures to Diplostomum spathaceum (Trematoda: Diplostomidae) cercarial survival

The toxicity of cadmium and zinc mixtures at concentrations ranging from 0.1 to 10,000 μg/L was investigated against the survival of the free-living cercarial stage of the parasitic fluke Diplostomum spathaceum. Cercariae were exposed to metal mixtures of equal concentration, metal mixtures of unequal concentration, and low-dose pretreatment followed by high-dose exposure mixtures. Under all exposures cercarial survival was increased compared to that achieved with single metals. At exposures with metal mixture of equal concentration in the range 0.1–100 μg/L survival was increased compared to that achieved by controls. The mechanism of metal toxicity and their effects on cercarial survival are discussed. Received: 17 November 2001/Accepted: 4 February 2002     

Distribution of Heavy Metal Residues in Fish from the River Nile Tributaries in Egypt

The distribution patterns of some metals (zinc, iron, copper, cadmium and lead) in fish samples collected from El Menofiya Governorate, Egypt were studied. The samples were collected from El Menofiya, canal water supplies (El Sarsawia, El Bagoria and Bahr Shebin), in addition to El Embaby, El Menofi and Miet Rabiha drainage canals each 2 month during periods of 16 month, June 2007–Septemper 2008. In the present investigation, the high concentrations of metals were found in fish samples collected from the drainage canal. The highest mean concentration of lead (1.864 μg/g), copper (1.495 μg/g) and cadmium (1.840 μg/g) were found in fish samples collected from El-Embaby drain. While the highest mean concentration of iron (108.26 μg/g) and zinc (24.35 μg/g) were present in fish samples collected from Miet-Rabiha drain. Lead and cadmium were found in higher concentration than those recommended by FAO for fish.     

Toxicity of Metal Pyrithione Photodegradation Products to Marine Organisms with Indirect Evidence for Their Presence in Seawater

We evaluated the acute toxicities of the metal pyrithiones (MePTs)—copper pyrithione (CuPT) and zinc pyrithione (ZnPT)—to four species of marine algae and a marine crustacean (Tigriopus japonicus). We also performed acute toxicity tests using six of the main MePT photodegradation products: pyridine-N-oxide (PO); 2-mercaptopyridine (HPS); pyridine-2-sulfonic-acid (PSA); 2-mercaptopyridine-N-oxide (HPT); 2,2′-dithio-bis-pyridine ([PS]₂); and 2,2′-dithio-bis-pyridine-N-oxide ([PT]₂)—and three marine organisms representing three trophic levels: an alga (Skeletonema costatum), a crustacean (T. japonicus), and a fish (Pagrus major). The acute toxicity values (72-h EC₅₀) of CuPT, ZnPT, HPT, (PT)₂, (PS)₂, HPS, PO, and PSA for S. costatum, which was the most sensitive of the test organisms to the chemicals tested, were 1.5, 1.6, 1.1, 3.4, 65, 730, >100,000, and >100,000 μg l⁻¹, respectively. CuPT was detected in the growth media used for S. costatum tests and in seawater containing HPT or (PT)₂; the concentration of CuPT in seawater containing HPT was highly dependent on the Cu²⁺ concentration. These results indicate that in the presence of sufficient Cu²⁺, the toxicities of HPT and (PT)₂ should be assessed as CuPT because in Japan MePTs are most frequently used as antifouling booster biocides in conjunction with cuprous oxide.     

Changes in Selenium, Copper, Cadmium, and Zinc Concentrations in Mullet (Mugil cephalus) from the Southern Basin of Lake Macquarie, Australia, in Response to Alteration of Coal-Fired Power Station Fly Ash Handling Procedures

Selenium, copper, cadmium, and zinc concentrations were measured in mullet (Mugil cephalus) from the southern basin of Lake Macquarie, Australia, in 1997 to determine if improved ash-handling practices at an adjacent coal fired power station, implemented in 1995, had significantly lowered trace metal concentrations in mullet tissues. Mean muscle tissue concentrations of selenium (5.9 ± 0.7 μg/g dry mass), copper (3.6 ± 0.1 μg/g dry mass), and zinc (14 ± 1 μg/g dry mass) are lower than previously reported for mullet analyzed in 1993 (10 ± 2, 21 ± 3, 27 ± 3 μg/g dry mass, respectively). Cadmium concentrations in liver tissues increased from 2.3 ± 0.3 to 6 ± 2 μg/g dry mass. Significant intra-tissue correlations between metal concentrations were found for all tissues except muscle. Strong correlations of selenium, copper, and zinc concentrations were found in liver tissues, indicating a common primary source may exist for these metals, such as fly ash. All trace metals were found to have significant inter-tissue correlations, with strong correlations occurring for selenium between all tissues and for cadmium between all tissues except muscle. Regulation of copper, cadmium, and zinc appears to be occurring in muscle tissue. Selenium concentrations in mullet are still above levels considered to be of concern to human consumers. Trace metal concentrations are below that known to effect the health of fish. Mullet are directly exposed to trace metal concentrations as a result of feeding and the ingestion of contaminated sediment and detritus. Lower metal concentrations found in mullet tissues are attributed to the burial of highly contaminated sediment with material containing lower trace metal concentrations. Little of the variations in trace metal concentrations between mullet was explained by mass, gender, or age. Received: 20 August 2000/Accepted: 22 February 2001     

Comparative Toxicity of Dissolved Metals to Early Larval Stages of Palaemon serratus, Maja squinado, and Homarus gammarus (Crustacea:Decapoda)

The acute lethal toxicities of mercury, copper, and cadmium to the first larval stage of the prawn (Palaemon serratus), spider crab (Maja squinado), and lobster (Homarus gammarus) were tested. Chromium was also tested with the prawn. Mortality was recorded after 48 h (for lobster) or 72 h (for other species) incubation at 18°C, and the median lethal concentrations (LC₅₀± 95% confidence intervals) per individual and per mass unit were calculated. The LC₅₀ values were, 74 μg Hg/L, 3,304 μg Cu/L, 1,686 μg Cd/L, 12,486 μg Cr/L for prawn; 72 μg Hg/L, 50 μg Cu/L, 158 μg Cd/L for spider crab; and 48 μg Hg/L, 46 μg Cu/L, 34 μg Cd/L for lobster. Therefore, larvae of spider crab and lobster were markedly more sensitive than prawn to heavy metals and thus more suitable to use in seawater quality bioassays. Of these two species, spider crab is recommended due to its abundance, easier maintenance, and higher fecundity. The mercury LC₅₀ values for different larval stages of P. serratus (zoea I, II, V, and VI) were obtained, and no ontogenetic change in sensitivity to the metal could be detected. Received: 24 January 2000/Accepted: 3 May 2000     

Assessment of the Metal Bioaccumulation in Three Species of Freshwater Bivalves

The metal concentration and body burden of three species of fresh water bivalves, Parreysia cylindrica, Parreysia corrugata and Corbicula striatella were estimated in laboratory experiment after exposure to chronic concentration of arsenic (0.1719 ppm), cadmium (0.23 ppm), copper (0.13 ppm), mercury (0.06 ppm), lead (2.4 ppm) and zinc (5.1 ppm) separately up to 30 days. Dry weight of each animal was used to calculate metal concentrations (μg/g) and the metal body burden (μg/individual). It was observed that zinc, lead and copper concentration and metal body burden was highest in the Corbicula striatella, mercury and arsenic was highest in Parreysia corrugata and cadmium was highest in Parreysia cylindrica. Therefore, Corbicula striatella is being proposed as sentinel organism for monitoring of zinc, lead and copper, Parreysia corrugata for mercury and arsenic, and Parreysia cylindrica for cadmium in fresh water ecosystem.     

Comparative Cytotoxicity of Alachlor on RTG-2 Trout and SH-SY5Y Human Cells

The cytotoxic effects of the herbicide alachlor were compared on rainbow trout gonadal RTG-2 and human neuroblastoma SH-SY5Y cell lines. The end points evaluated in both cells after 24, 48, and 72 h of exposure were total protein content (PC), lysosomal function, and mitochondrial’s integrity by mitochondrial succinate dehydrogenase (SDH) activity. After 24 h, cytoplasmic membrane integrity by cytosolic lactate dehydrogenase (LDH) leakage and LDH intracellular activity were also studied. In addition, acetylcholinesterase activity (AChE) was quantified in SH-SY5Y cells. The possible biotransformation of alachlor by RTG-2 cells was investigated by analyzing the exposure culture medium by liquid chromatography–mass spectrometry. In RTG-2, EC₅₀ values on PC, lysosomal function, and SDH activity after 24 h exposure ranged from 80 to 95 μM and decreased to approximately 40 μM for longer exposure time periods. SH-SY5Y cells were slightly more sensitive than RTG-2 cells, with EC₅₀ values on PC and lysosomal function ranging from 87 to 75 μM at 24 h and decreasing to 47 μM and 34 μM at 72 h, respectively. AChE activity was increased, being the most sensitive marker for SH-SY5Y with an EC₅₀ of 20 μM at 24 h. The metabolic enzyme SDH was stimulated in SH-SY5Y and reduced in RTG-2 cells. At the studied conditions, no metabolites of alachlor were detected in RTG-2 cultures. In conclusion, the proposed battery approach is an effective screening tool for the safety assessment of environmental contaminants as a complement to fish and animal toxicity procedures.     

Acrosome Reaction of Sperm in the Mud Crab Scylla serrata as a Sensitive Toxicity Test for Metal Exposures

In order to test the sensitivity of the sperm cell of the mud crab Scylla serrata to heavy metals, the toxic effects of Ag⁺, Cd²⁺, Cu²⁺, and Zn²⁺ on the acrosome reaction (AR) were studied by artificially inducing the AR of sperm exposed to heavy metals, counting the AR rates by light microscopy, and observing structural changes in sperm by transmission electron microscopy. The AR in S. serrata occurs at two stages. The first stage (ARI) is the eversion of the subacrosomal material. The second stage (ARII) is the ejection of the acrosomal filament. The results showed the EC₅₀ values of the AR based on (ARI + ARII)% for Ag⁺, Cd²⁺, Cu²⁺, and Zn²⁺ were 10.02, 2.14, 13.69, and 2.21 μg/L, and the EC₅₀ values based on ARII % of Ag⁺, Cd²⁺, Cu²⁺, and Zn²⁺ were 1.96, 0.20, 1.46, and 0.34 μg/L. The order of toxicity is Cd²⁺ > Zn²⁺ > Cu²⁺ > Ag⁺ based on the percentage of reacted sperm at the second stage. Sperm cells exposed to heavy metals showed an increased rate of swelling, shape irregularities, and the acrosomal filament of some sperm cells was, crooked, ruptured, and even dissolved. The AR of the sperm cell from S. serrata is more sensitive to the tested heavy metals compared to sea urchin sperm cell toxicity tests.