Cadmium in freshwater and marine water

​​Toxicant default guideline values for protecting aquatic ecosystems

October 2000

Extracted from Section 8.3.7 ‘Detailed descriptions of chemicals'​ of the ANZECC & ARMCANZ (2000) guidelines.

The default guideline values (previously known as ‘trigger values’) and associated information in this technical brief should be used in accordance with the detailed guidance provided in the Australian and New Zealand Guidelines for Fresh and Marine Water Quality.

Description of chemical

In natural surface waters, cadmium occurs predominantly in the divalent form, comprising several inorganic and organic compounds (Reeder et al. 1979). The solubility of dissolved cadmium decreases with increasing pH and alkalinity (French 1986). Low background levels of cadmium are found in many natural waters (Table 8.3.2 in the ANZECC & ARMCANZ 2000 guidelines).

Cadmium may be accumulated by a number of aquatic organisms, with bioconcentration factors in the order of 100 to 100,000 (Reeder et al. 1979).

Summary of factors affecting cadmium toxicity

  • Cadmium toxicity is hardness-dependent and an algorithm is available (Table 3.4.3 in the ANZECC & ARMCANZ 2000 guidelines).
  • Cadmium is less toxic in freshwater at lower pH, although toxicity is reduced above pH 8 (algorithms should account for this).
  • Dissolved organic matter reduces cadmium toxicity. The effect of organic complexation requires experimental determination.
  • Cadmium is absorbed strongly by suspended material. Filtration and speciation measurements should account for this.
  • Cadmium complexes with chloride, resulting in reduced toxicity at higher salinity.
  • Cadmium has a variable tendency to bioaccumulate but bioconcentration can be significant for bivalves in marine and estuarine situations.

A variety of methods are available for determining the speciation of cadmium in water. These include:

  • Analytical techniques, such as physical separation (e.g. [ultra]filtration, dialysis, centrifugation), potentiometry (e.g. ion-selective electrode), voltammetry (e.g. anodic stripping voltammetry), ion exchange and chromatography (Florence & Batley 1980, Holm et al. 1995, Apte & Batley 1995)
  • Theoretical techniques, such as geochemical modelling (Mantoura et al. 1978, French 1986, Paalman et al. 1994, Holm et al. 1995).

Bioassays are typically used to ascertain metal-organism interactions. These can be coupled with the measured and/or predicted speciation of cadmium to determine the bioavailable cadmium species. The current analytical practical quantitation limit (PQL) for cadmium is 0.05 µg/L in fresh water and 1.0 µg/L in marine water (NSW EPA 2000).

Factors that affect the bioavailability and toxicity of cadmium

It is generally considered that the free cadmium ion (Cd2+) is the form of cadmium primarily responsible for eliciting a toxic response in aquatic organisms (Campbell 1995) and is the predominant species of dissolved cadmium in fresh surface waters at pH 8.5 (Moore & Ramamoorthy 1984a, French 1986). Cadmium complexes with inorganic and/or organic ligands/agents generally reduce the uptake and toxicity of the metal by reducing the concentration of Cd2+. Cadmium typically forms weak complexes with natural dissolved organic matter (DOM) in fresh and marine waters (Moore & Ramamoorthy 1984a, Marinsky et al. 1985). In waters with a high natural DOM content, sorption of cadmium to organic matter and other complexing agents can be important (Tessier et al. 1996). The formation of cadmium-DOM complexes is usually greatest under conditions of low hardness and alkalinity, neutral pH and high natural DOM (Giesy 1980). Redox potential is believed to have little direct influence on cadmium speciation.

Sorption to clay, mineral and biotic surfaces is probably the most important process for the removal of cadmium from solution (Dzombak & Morel 1990, Majidi et al. 1990, Goldberg et al. 1996). Sorption of cadmium to particles and organic matter increases with pH, until a threshold point is reached, usually around pH 8 (Dzombak & Morel 1990, Wagemann et al. 1994). The sorption of cadmium to particles and organic matter typically declines with increasing salinity (Greger et al. 1995). Conflicting results have been reported on the bioavailability of cadmium adsorbed to suspended particles. Some studies have shown that the bioavailability of cadmium is similar for both the dissolved phase and particulate phases (Cossa 1988). Such differences are dependent on the feeding habit (e.g. filter feeding) of the organism, as well as the water and sediment chemistry.

It is well established that the uptake and toxicity of cadmium in freshwater organisms decreases with increasing water hardness and alkalinity [see reviews by Sprague (1987), Spry & Wiener (1991) and Wren et al. (1995)]. For example, Palawski et al. (1985) reported that the 96-hour LC50 for striped bass (Morone saxatilis) was 3.7 µg Cd/L in soft water (40 mg/L as CaCO3; alkalinity, 30 mg/L as CaCO3; pH 8.1). In contrast, it was 27.0 µg Cd/L in hard water (285 mg/L as CaCO3; alkalinity, 262 mg/L as CaCO3; pH 7.9). An exponential, inverse relationship has been demonstrated between water hardness and the uptake and toxicity of cadmium. An algorithm describing this relationship has been used to calculate a hardness-modified cadmium guideline value for protecting aquatic ecosystems in North America (USEPA 1995a,b).

The uptake and toxicity of cadmium in freshwater organisms generally decreases with decreasing pH (i.e. increasing H+ concentration) (e.g. Peterson et al. 1984, Cusimano et al. 1986, Krantzberg & Stokes 1988, Schubauer-Berigan et al. 1993) over the pH range 3.5 to 8.5. In contrast, Gerhardt (1992) showed a negligible change in the toxicity of cadmium to three freshwater invertebrates over the pH range 5 to 7.

In seawater, dissolved cadmium is dominated by chloride-complexes (Fergusson 1990). The formation of cadmium–chloride complexes declines with decreasing salinity (i.e. chloride concentration), until the free hydrated ion (Cd2+) becomes dominant at 2 (Raspor 1980). It has been generally established that the uptake and toxicity of cadmium in aquatic organisms increases with decreasing salinity, that is, more estuarine situations (Mayer et al. 1989, Gossiaux et al. 1992, de Lisle & Roberts 1994, Wang et al. 1996). Variation of toxicity with temperature seems to be species-specific (USEPA 1986). The chronic data available appear to reflect the effects of salinity and temperature (USEPA 1986).

Bioaccumulation

Cossa (1988) reported results of a worldwide survey of cadmium in mussel Mytilus edulis tissue, with regional concentrations varying from 0.6 to 3.3 mg/kg. The concentration factor between the mussel and its environment was between 10,000 and 20,000. Reliable seawater concentrations from seven regions allowed development of a relationship between cadmium concentrations in seawater (Cdsw; mg/L) and in mussel tissue (Cdm; mg/kg):

Cdm = 0.74 Cdsw + 0.39

Concentrations of cadmium in the Gironde Estuary in France of between 0.2 mg/L and 0.4 mg/L were associated with mussel concentrations of between 12 mg/kg and 37 mg/kg. Based on the then proposed maximum Cd concentration of 10 mg/kg for human consumption, Cossa (1988) derived a maximum water concentration of around 0.2 µg/L.

Long et al. (1997) reported the accumulation of cadmium in two species of Australian dolphin and their prey. Cadmium accumulated in kidney up to 38 mg/kg and levels in 32% of dolphins in southern Australia were associated with histopathological lesions. This indicates the potential for cadmium to cause secondary poisoning in marine systems.

Jarvinen and Ankley (1999) report data on tissue residues and effects for 35 freshwater species and 25 marine species. It is not possible to summarise the data here but readers are referred to that publication for more information. Ward (1982) reported that Sydney rock oyster exposed to 25 µg/L of cadmium chloride accumulated between 48 and 72 mg/kg wet weight, resulting in 100% mortality after 60 days. Exposure to 10 µg/L for 112 days had no effect on survival and tissue concentrations around 25 mg/kg.

Aquatic toxicology

Acute toxicity of cadmium to freshwater animal species in 44 genera ranged from 1 µg/L for rainbow trout to 28,000 µg/L for mayfly (USEPA 1986). CCREM (1987) noted that the species mean acute toxicity value for rainbow trout was 3.6 µg/L. The acute values for 30 marine invertebrates ranged from 15.5 µg/L upward (USEPA 1985f). Cadmium up to 200 µg/L did not inhibit fertilisation success of gametes from Australian scleractinian reef corals (Reichelt-Brushett & Harrison 1999).

Fresh

water guideline

A total of 73 chronic data points were available for cadmium, after screening for quality, for values associated with hardness measurements and for other reasons listed in Section 8.3.4.4 in the ANZECC & ARMCANZ (2000) guidelines. These were adjusted for low hardness (30 mg/L as CaCO3) and other end-points were also adjusted to NOECs using the method adapted from van de Plassche et al. (1993). They comprised the following (expressed as geometric means of NOECs for species and end-points adjusted for low hardness):

Fish: nine species, geometric means ranged from 0.49 µg/L (Oncorhynchus tshawytscha; adjusted fromLC50) to 767 µg/L for Salmo salar. The lowest measured chronic figure (hardness-corrected) was 0.5 µg/L for O. mykiss (LOEC).

Amphibians: one species, Ambystoma opacum, NOEC (mortality) of 10.2 µg/L.

Crustaceans: six species, geometric means for species and end-points ranged from 0.08 µg/L for Daphnia magna to 3.2 µg/L for Asellus aquaticus, although the crayfish Orconectes virillis, had a NOEC (geometric mean) of 122 µg/L.

Insects: two species, means for NOECs of 0.52 to 0.82 µg/L.

Algae: three species, means for NOECs of 8.2 to 32 µg/L.

A high reliability freshwater trigger value of 0.2 µg/L was derived for cadmium using the statistical distribution method at 95% protection. This figure applies to a low hardness of 30 mg/L as CaCO3. The 95% protection level was above the geometric mean for NOECs for D. magna. It is not, however, above any experimental chronic figure but several chronic LC50s or NOECs were around 0.3 to 0.6 µg/L, after correction for low hardness. The 95% protection level was considered sufficiently protective for most such systems. If water managers are concerned about related species, the 99% protection level (0.06 µg/L) could be used for slightly to moderately disturbed ecosystems, but users are advised to check the spread of data (Section 8.3.7 in the ANZECC & ARMCANZ 2000 guidelines).

Marine guideline

After screening, a total of 175 chronic data points comprising eight taxonomic groups, were available for cadmium in the marine environment. These consisted of a variety of end-points and were corrected to NOEC equivalents using the method described previously. The NOEC data varied as follows:

Fish: six species, 108 µg/L (Menidia menidia, from 19-day LC50) to 16,000 µg/L (Tilapia mossambica, 7-d LC50)

Crustaceans: 19 species, 0.45 µg/L (Mysidiopsis bahia, from 18-day MATC, growth of 0.9 µg/L) to 10,400 (Uca pugilator, 8-day LC50). Geometric means below 25 µg/L were encountered for six species for at least one end-point. The geometric mean for M. bahia growth was 2.75 µg/L.

Echinoderms: one species, Asterias forbesi, 140 µg/L, from 7-day LC50.

Molluscs: five species, 30 mg/L (Mya arenaria, from 7-day LC50) to 3200 µg/L (Nassarius obsoletus), although only the gastropod had values >600 µg/L.

Annelids: five species, 7.8 µg/L (Neanthes arenaceodentata, from 28-day LC50) to 1302 µg/L.

Nematodes: one species, Monhystera disjuncta, 400 to 10,000 µg/L.

Rotifers: one species, Brachionus plicatilis, 3-day LC50, 1040 µg/L.

Algae: two species, 5.7 µg/L (Champia parvula, from 14-day MATC, reproduction) to 1780 µg/L (Skeletonema costatum, from 10-day EC50, population growth).

A high reliability marine guideline value for cadmium of 5.5 µg/L was calculated using the statistical distribution method with 95% protection. The 99% protection level is 0.7 µg/L, and is recommended for slightly to moderately disturbed ecosystems. The 95% protection level was above the geometric mean of NOECs for several marine crustaceans. To protect against chronic toxicity to related species and bioaccumulation of cadmium, use of the 99% protection level (0.7 µg/L) is recommended for slightly-moderately disturbed ecosystems. If in an area where shellfish are likely to be used for human consumption, the trigger value should be reduced to 0.2 µg/L.

References

ANZECC & ARMCANZ 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Australian and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand, Canberra.

Apte SC & Batley GE 1995. Trace metal speciation of labile chemical species in natural waters and sediments: Non-electrochemical approaches. In Metal speciation and bioavailability in aquatic systems, eds A Tessier & DR Turner, John Wiley & Sons, Chichester, 259–306.

Campbell PGC 1995. Interactions between trace metals and aquatic organisms: A critique of the free-ion activity model. In Metal speciation and bioavailability in aquatic systems, eds A Tessier & DR Turner, John Wiley & Sons, Chichester, 45–102.

CCREM 1987. Canadian water quality guidelines. Canadian Council of Resource and Environment Ministers, Ontario.

Cossa D 1988. Cadmium in Mytilus spp.: Worldwide survey and relationship between seawater and mussel content. Marine Environmental Research 26, 265–284.

 Cusimano RF, Brakke DF & Chapman GA 1986. Effects of pH on the toxicities of cadmium, copper, and zinc to steelhead trout (Salmo gairdneri). Canadian Journal of Fisheries and Aquatic Sciences 43, 1497–1503.

de Lisle PF & Roberts MH 1994. The effect of salinity on cadmium toxicity in the estuarine mysid Mysidopsis bahia: Roles of osmoregulation and calcium. Marine Environmental Research 37, 47–62.

Dzombak DA & Morel FMM 1990. Surface complexation modeling: Hydrous ferric oxide. John Wiley & Sons, New York.

Fergusson JE 1990. The heavy elements: Chemistry, environmental impact and health effects. Pergamon Press, Oxford.

Florence TM & Batley GE 1980. Chemical speciation in natural waters. Critical Reviews in Analytical Chemistry 9, 219–296.

French P 1986. The speciation and solubility of copper and cadmium in natural waters. Environmental Report 1226-M, Water Research Centre—Environment, Medmedham, UK.

Gerhardt A 1992. Acute toxicity of Cd in stream invertebrates in relation to pH and test design. Hydrobiologia 239, 93-100.

Giesy JP 1980. Cadmium interactions with naturally occurring organic ligands. In Cadmium in the environment. Part 1. Ecological cycling, ed JO Nriagu, John Wiley & Sons, New York, 237–256.

Goldberg S, Davis JA & Hem JD 1996. The surface chemistry of aluminium oxides and hydroxides. In The environmental chemistry of aluminium,2nd edn, ed G Sposito, Lewis Publishers, Boca Raton, FL, 271–331.

Gossiaux DC, Landrum PF & Tsymbal VN 1992. Response of the amphipod Diporeia sp. to various stressors: Cadmium, salinity and temperature. Journal of Great Lakes Research 18, 364–371.

Greger M, Kautsky L & Sandberg T 1995. A tentative model of cadmium uptake in Potamogeton pectinatus in relation to salinity. Environmental and Experimental Botany 35, 215–225.

Holm PE, Andersen S & Christensen PH 1995. Speciation of dissolved cadmium: Interpretation of dialysis, ion exchange and computer (GEOCHEM) methods. Water Research 29, 803–809.

Jarvinen AW & Ankley GT 1999. Linkage of effects to tissue residues: Development of a comprehensive database for aquatic organisms exposed to inorganic and organic chemicals. SETAC Technical Publication Series, SETAC Press, Pensacola FL.

Krantzberg G & Stokes PM 1988. The importance of surface adsorption and pH in metal accumulation by chironomids. Environmental Toxicology and Chemistry 7, 653–670.

Long M, Reid RJ & Kemper CM 1997. Cadmium accumulation and toxicity in the bottlenose dolphin Tursiops truncatus, the common dolphin Delphinus delphis and some dolphin prey species in South Australia. Australian Mammalogy 20, 25–33.

Majidi V, Laude DA & Holcombe JA 1990. Investigation of the metal-algae binding site with 113Cd nuclear magnetic resonance. Environmental Science and Technology 24, 1309–1312.

Mantoura RFC, Dickson A & Riley JP 1978. The complexation of metals with humic materials in natural waters. Estuarine and Coastal Marine Science 6, 387–408.

Marinsky JA, Mathuthu A, Bicking M & Ephraim J 1985. Complex forming properties of natural occurring fulvic acids. Part 1. Complexes with cadmium, copper and calcium. SKB Technical Report 85–07. Svensk Kärnbränslehantering AB, Stockholm.

Mayer FL, Marking LL, Pedigo LE & Brecken JA 1989. Physicochemical factors affecting toxicity: pH, salinity, and temperature. I. Literature review.

EPA/600/X-89/033. United States Environmental Protection Agency, Washington DC.

Moore JW & Ramamoorthy S 1984a. Cadmium. In Heavy metals in natural waters: Applied monitoring and impact assessment, Springer-Verlag, Berlin, 28–57.

NSW EPA 2000. Analytical Chemistry Section, Table of Trigger Values 20 March 2000, LD33/11, Lidcombe, NSW.

Paalman MAA, van der Weijden CH & Loch JPG 1994. Sorption of cadmium on suspended matter under estuarine conditions: Competition and complexation with major seawater ions. Water Air and Soil Pollution 73, 49–60.

Palawski D, Hunn JB & Dwyer FJ 1985. Sensitivity of young striped bass to organic and inorganic contaminants in fresh and saline waters. Transactions of the American Fisheries Society 114, 748–753.

Peterson HG, Healey FP & Wagemann R 1984. Metal toxicity to algae: A highly pH dependent phenomenon. Canadian Journal of Fisheries and Aquatic Sciences 41, 974–978.

Raspor B 1980. Distribution and speciation of cadmium in natural waters. In Cadmium in the environment. Part 1. Ecological cycling, ed JO Nriagu, John Wiley & Sons, New York. 147–236.

Reeder SW, Demayo A & Taylor MC 1979. Cadmium. In Guidelines for surface water quality. Vol. 1: Inorganic chemical substances, Water Quality Branch, Inland Waters Directorate, Environment Canada, Ottawa.

Reichelt-Brushett AJ & Harrison PL 1999. The effect of copper, zinc and cadmium on fertilization success of gametes from scleractinian reef corals. Marine Pollution Bulletin 38, 182–187.

Schubauer-Berigan MK, Dierkes JR, Monson PD & Ankley GT 1993. pH-dependent toxicity of Cd, Cu, Ni, Pb and Zn to Ceriodaphnia dubia, Pimephales promelas, Hyalella azteca and Lumbricus variegatus. Environmental Toxicology and Chemistry 12, 1261–1266.

Sprague JB 1987. Effects of cadmium on freshwater fish. In Cadmium in the aquatic environment, eds JO Nriagu & JB Sprague, John Wiley & Sons, New York, 139–169.

Spry DJ & Wiener JG 1991. Metal bioavailability and toxicity to fish in low-alkalinity lakes: A critical review. Environmental Pollution 71, 243–304.

Tessier A, Fortin D, Belzile N, DeVitre RR & Leppard GG 1996. Metal sorption to diagenetic iron and manganese oxyhydroxides and associated organic matter:

Narrowing the gap between field and laboratory measurements. Geochimica et Cosmochimica Acta 60, 387–404.

USEPA 1995a. Great Lakes water quality initiative criteria documents for the protection of aquatic life in ambient water. US Environmental Protection Agency, Washington DC. EPA-820-B-95-004.

USEPA 1986. Quality criteria for water. US Department of Commerce, National Technical Information Service, US Environmental Protection Agency, Springfield, Virginia. PB87-226759, EPA 440/5 86-001.

USEPA 1985f. Ambient water quality criteria for cadmium—1984. EPA-440/5-84-032. Criteria and Standard Division, US Environmental Protection Agency, Washington DC.

USEPA 1995b. Stay of federal water quality criteria for metals. Federal Register 60, 22228-22237.

van de Plassche EJ, Polder MD & Canton JH 1993. Derivation of maximum permissible concentrations for several volatile compounds for water and soil. National Institute of Public Health and Environmental Protection, Report 679101 008, Bilthoven, The Netherlands.

Wagemann R, Capel MJ, Hesslein R & Stephenson M 1994. Sediment-water distribution coefficients and speciation of cadmium in a Canadian shield lake. Canadian Journal of Fisheries and Aquatic Sciences 51, 1951–1958.

Wang WX, Fisher NS & Luoma SN 1996. Kinetic determinations of trace element bioaccumulation in the mussel Mytilus edulis. Marine Ecology Progress Series 140, 91–113.

Ward TJ 1982. Laboratory study of the accumulation and distribution of cadmium in the Sydney rock oyster Saccostrea commercialis (L & R). Australian Journal of Marine and Freshwater Research 33, 33–44.

Wren CD, Harris S & Harttrup N 1995. Ecotoxicology of mercury and cadmium. In Handbook of ecotoxicology, eds DJ Hoffman, BA Rattner, GA Burton & J Cairns, Lewis Publishers, Boca Raton, FL, 392–423.