Diphosphoric acid, copper salt

Toxicity to other aquatic organisms

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

An evaluation of the effects of low-level copper and pentachlorophenol exposure on various early life stages of the South African clawed frog, Xenopus laevis, was performed.

Test organisms (species):

Xenopus laevis

Test type:

flow-through

Water media type:

freshwater

Key result

Remarks on result:

other: Please refer to executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

An evaluation of the effects of low-level copper and pentachlorophenol exposure on various early life stages of the South African clawed frog, Xenopus laevis, was performed using stage-specific and long-term continuous exposures. Stage-specific exposure experiments were conducted such that separate subsets of embryos and larvae from the same clutch were exposed to two toxicants, copper and pentachlorophenol, from 0 d to 4 d (standard Frog Embryo Teratogenesis Assay —Xenopus [FETAX]), 4 d to 8 d, 8 d to 12 d, and 12 d to 16 d. Results from two separate concentration-response experiments indicated that sensitivity to either toxicant increased in each successive time period. Longer-term exposure studies conducted for 60 to 75 days indicated that copper, but not pentachlorophenol induced reduction deficiency malformations of the hind limb at concentrations as low as 0.05 mg/L. Pentachlorophenol concentrations as low as 0.5μg/L inhibited tail resorption. However, copper did not adversely affect the process of tail resorption. These results indicated that studies evaluating longer-term developmental processes are important in ecological hazard evaluation.

Reference 2

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

The effects of the chelating agent ADTA-Na salt on the acute toxicities of Cu and Zn on the tadpoles of the frog Rana hexadactyla was investigated in available natural soft water.

Test organisms (species):

Rana hexadactyla

Water media type:

freshwater

Key result

Remarks on result:

other: Please refer to the executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

Relatively limited information is available on the toxicity of copper and zinc on frog and its tadpoles. Heavy metallic ions were found to be made biologically less active and toxic by chelating agents like sodium salt of EDTA or NTA. Aim of the present study was to investigate the effects of the chelating agent ADTA-Na salt on the acute toxicities of Cu and Zn on the tadpoles of the frog Rana hexadactyla in available natural soft water.

Frog tadpoles in Cu and Zn toxicants showed abnormal behavioural symptoms such as hyperactivity and loss of equilibrium. In higher concentrations of toxicants, the test animals remained for a time at the surface, gulping air, and lost their equilibrium; then they gradually moved to the bottom of the test jars. EDTA caused a marked decrease in Cu and Zn toxicity. Survival times of animals also increased: for example at 0.5 ppm of Cu alone, all the tadpoles died within 12 h while with the addition of 4 ppm of EDTA to the 0.56 ppm of Cu, it caused a 100% mortality in 72 h and 60% in 12 h. Although Cu toxicity decreased with every added EDTA concentration, a much lower overall decrease in toxicity was observed in the presence of 5 and 10 ppm EDTA.

In conclusion, addition of EDTA salt to Cu and Zn concentrations caused a great decrease in toxicity of the metals, proportional to the amount of EDTA added. The effect was more pronounced with Cu than Zn.

Reference 3

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Five freshwater species (amongst which tadpole larva of R. Tigrina).

Test organisms (species):

Rana tigrina

Water media type:

freshwater

Key result

Remarks on result:

other: Please refer to the executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

Copper pollutants require much attention for improving the water criteria and the laboratory bioassays with divergent aquatic species would prove to be a precious tool in evaluating problems of copper toxicity. Five species of freshwater habitat were used for toxicity studies: tadpole larva of Rana Tigrina, common guppy Lebistes reticulates (Peters), Raspora deniconius neilgeriensis (Hamliton), pond snail Viviparous bengalensis (L.) and pulmonate snai lLymnaea accuminata (Lamarck). 7-10 copper concentrations were tested. A progressive decline in LC50s between 12 h and 96 h was observed. The results indicate that L. reticulates were most resistant while L. accuminata were most sensitive animals and Rasbora, V. bengulensis and tadepole larva were intermediate. In general, most of the copper-treated animals died in 48 h of exposure and after 72 h, death rate rapidly declined. No mortality was observed on control jars and test animals appeared healthy and normal.

In conclusion, these results suggested that water quality criteria for chemicals entering into surface waters require an understanding of acute toxicity tests with both the vertebrate and invertebrate aquatic species under different environmental conditions.

Reference 4

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

The primary focus of this study was to determine if exposure to sublethal concentrations of copper would cause behavioral changes that may leave Rana pipiens tadpoles more susceptible to secondary stressors. Secondarily, recovery times after sublethal exposures with regard to length of tadpole were determined.

Test organisms (species):

Rana pipiens

Remarks on result:

other: Please refer to the executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

The primary focus of this study was to determine if exposure to sublethal concentrations of copper would cause behavioral changes that may leave Rana pipiens tadpoles more susceptible to secondary stressors. Secondarily, recovery times after sublethal exposures with regard to length of tadpole should be determined. Claculated LC₅₀values for the 7-day exposure was 0.067 mg/L Cu, although mortality was induced at concentrations as low as 0.036 mg/L. Behavioral changes included lethargy, loss of equilibrium and apparent loss of appetite (0.036 mg/L). The aberrant behavior continued until tadpoles were removed or mortality occurred. Affected tadpoles appeared to display normal behavior within one week after transition to uncontaminated solution. Tadpole growth was decreased at Cu concentrations above 0.071 mg/L. After 19 days of recovery, size was similar in all groups.

The results suggested that brief exposure to Cu may not have lasting effects becauseR. pipiensexposed to sublethal Cu concentrations, recovered once the stressor was removed. Because most aquatic predators are visually.

Reference 5

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Southern leopard frog (Rana sphenocephala) tadpoles were exposed to five chemicals (4 -nonylphenol, carbaryl, copper, pentachlorophenol, permethrin). LC50s were determined and compared with published values for organisms more commonly used in toxicological testing.

Test organisms (species):

Rana sphenocephala

Key result

Remarks on result:

other: Please refer to executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

Southern leopard frog (Rana sphenocephala) tadpoles were exposed to five chemicals (4 -nonylphenol, carbaryl, copper, pentachlorophenol, permethrin), each having a different mode of action. These chemicals have been used as model chemicals in previous studies to determine the sensitivity of fish and amphibian larvae to contaminants with differing modes of action. Southern leopard frogs are common throughout the eastern and southern U.S., often breeding in shallow pools or temporary ponds situated near or within agricultural areas. Therefore, this species may commonly come into contact with any number of chemical contaminants. Southern leopard frogs are not known to be in decline and are widely distributed across the southeastern U.S., and can act as a model amphibian species. The objective of the research was to determine the LC50s of southern leopard frog tadpoles and compare them with published values for organisms more commonly used in toxicological testing, while testing the hypothesis that amphibians are more sensitive to contaminants than fish.

Reference 6

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Some effects of Cu on the liver, the impact of Cu on two biomarkers of exposure, lipid peroxidation and glutathione (GSH) were examined. Therefore, the levels of malondialdehyde (MDA; lipid peroxidation product), GSH and Cu concentration in the liver of Rana ridibunda were measured.

Test organisms (species):

Rana ridibunda

Water media type:

freshwater

Remarks on result:

other: Please refer to the executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

The aim of the study was to examine some effects of Cu on the liver, the impact of Cu on two biomarkers of exposure, lipid peroxidation and glutathione (GSH). Therefore, the levels of malondialdehyde (MDA; lipid peroxidation product), GSH and Cu concentration in the liver ofRana ridibundawere measured.

The frog seemed to face an oxidative stress over the first 15 days of Cu exposure, resulting in both lysosomal and antioxidant response (increasing levels for both, MDA and GSH in the liver). At the 30^thday of exposure, the highest concentrations of MDA resulted in an inhibition of further increased GSH levels.

Reference 7

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

The effect of copper (Cu) deficiency on the reproduction and development in Xenopus laevis was evaluated, culminating in the development of a defined concentration-response relationship. At the same time, information on adverse effects of increased Cu levels was generated.

GLP compliance:

not specified

Test organisms (species):

Xenopus laevis

Water media type:

freshwater

Key result

Remarks on result:

other: Please refer to executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

The effect of copper (Cu) deficiency on the reproduction and development in Xenopus laevis was evaluated, culminating in the development of a defined concentration-response relationship. At the same time, information on adverse effects of increased Cu levels was generated.

Separate groups of four adult frog pairs were fed one of three diets for 28 d: (1) low-copper (-Cu); (2) copper supplemented (+Cu); and (3) ASTM standard beef liver and lung (BLL). Embryos collected from frogs administered the -Cu diet had markedly decreased egg masses and viability rates and an increased rate of necrosis when compared to the other dietary treatments. Malformations in -Cu larvae included maldevelopment of the heart, eye, craniofacial region, brain, and notochord. Larvae from adults administered the -Cu diet showed delayed abnormal hindlimb development, characterized as selective reductive deficiencies distal to the femur, with poor cartilaginous development. A U-shaped dose-response curve characteristic of nutritional essentiality was developed for Cu. Embryonic malformations were observed at Cu concentrations of ≤ 0.5 and ≥ 500 µg Cu/L.

Overall, these studies indicated that embryos produced from frogs administered a -Cu diet are substantially less viable than embryos from frogs administered a +Cu or copper-adequate (BLL) diet.

Reference 8

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Sets of adult male and female Xenopus laevis were administered a a copper-deficient (-Cu) diet under low-copper culture conditions, or a copper-supplemented (+Cu) diet under ambient copper culture conditions, for 120 d in order to assess the effects on reproduction, early embryogenesis, or limb development in the progeny.

Test organisms (species):

Xenopus laevis

Water media type:

freshwater

Key result

Remarks on result:

other: Please refer to executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

Sets of adult male and female Xenopus laevis were administered a boron-deficient (-B) diet under low-boron culture conditions, a boron-supplemented (+B) diet under ambient boron culture conditions, a copper-deficient (-Cu) diet under low-copper culture conditions, or a copper-supplemented (+Cu) diet under ambient copper culture conditions, for 120 d. Adults from each group were' subsequently bred, and the progeny were cultured and bred. Results from these studies indicated that although pronounced effects on adult reproduction and early embryo-larval development were noted in the -B F₁generation, no effects on limb development were observed. No significant effects on reproduction, early embryogenesis, or limb development were noted in the +B group, irrespective of generation. Highly specific forelimb and hindlimb defects, including axial flexures resulting in crossed limbs and reduction deficits, were observed in -B F₂larvae, but not in the +B F₂larvae. As was noted in the boron-deficiency studies, significant effects on reproduction and early embryo development were observed in the -Cu F₁generation, but not in the +Cu F₁generation. Unlike the effects associated with boron deficiency, maldevelopment of the hindlimbs (32 responders, n = 40) was found in the F₁generation.

Reference 9

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

other: experimental result and review

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Embryo-larval bioassays were conducted

Test organisms (species):

Rana pipiens

Water media type:

freshwater

Key result

Remarks on result:

other: Please refer to the executive summary.

Validity criteria fulfilled:

not applicable

Executive summary:

Embryo-larval bioassays were conducted on four species of fish (Micropterus salmoides, Ictalurus punctatus, Carassius auratus, Salmo gairdneri) and five amphibians (Rana pipiens, Hyla chrysoscelis, Bufo fowleri, Gastrophryne carolinensis, Ambystoma opacum).

In the promulgation of protective standards for freshwater and marine aquatic life, it was concluded that exposure levels of 5 to 15 µg Cu/L produced harmful effects for several aquatic species, and that such concentrations were close to mean ambient values for fresh waters affected by copper. It appears from experimental data that growth and reproduction of most freshwater fish would be unobstructed by either short- or long-term exposure to copper at or below this concentration range. However, the limiting criterion for copper was set at “0.1 times the 96-hour LC₅₀as determined through nonaerated bioassays using a sensitive aquatic resident species (EPA, 1976). Using the adult fathead minnow as the test species and taking a 96-h TL_mof 430 µg/L gives a criterion for copper of 43 µg/L. Exposure levels of 5 to 10 µg/L produced appreciable frequencies of mortality and teratogenesis in static renewal tests with eggs of the rainbow trout and several species of amphibians. Even when calculations are based on data for 14-month-old brook trout, the limit for copper would be 10 µg/L, and this would not appear to provide adequate protection for embryos and larvae of certain vertebrate species.

Based on this, there is some need to re-evaluate the freshwater standard for copper. As the perpetuation of natural species is dependent in substantial measure on reproduction, criteria for copper should be compatible with the productive process. Reductions of only 5 – 10% in reproductive potential may prove deleterious when coupled with the effects of natural stresses on developmental stages. Therefore it would be more appropriate to base the limiting criteria for copper on tolerances of embryos, larvae, or early juveniles of sensitive resident species. On the basis of 96-h TL₅₀values of 18 – 20 µg/L for juvenile Chinook salmon and rainbow trout , the copper limit would be about 2 µg/L, and this is in close agreement with LC₁`s obtained in static renewal bioassays for rainbow trout eggs exposed from fertilization through 4 days posthatching. The toxicity of copper to developmental stages of fish and amphibians may be affected by hardness, alkalinity, and other characteristics of the test water. Larval and juvenile fish usually are most susceptible to copper administered in soft water, but copper in hard water may be equally or more toxic to eggs and embryos than to posthatched stages.

The present criterion for copper also may not be adequate to protect certain species of amphibians. Particular attention should be drawn to the fact that the developmental stages of three of the five amphibian species tested exhibited sensitivity equal to or greater than that observed for embryos and early larvae of the rainbow trout. Practival limits for copper probably should be established within ranges of 2 – 5 µg/L in soft or medium hard water and 5 – 8 µg/L in hard water to protect aquatic habitat frequented by sensitive fish and amphibian species, according to the present data.

Copper at 2 – 5 µg/L produced significant frequencies of teratic larvae in trout, and teratogenesis was a more sensitive test response than embryo-larval mortality in studies with the herring. However, for species with higher tolerances (e.g. bass, goldfish), anomalous larvae seldom were observed when copper was administered below median lethal concentrations.

The interaction of copper with other metals was highly dependent on exposure concentration. Copper-zinc and copper-mercury mixtures generally were additive but occasionally were antagonistic when fish eggs were treated at low concentrations, and synergism consistently was observed at higher exposure levels. Except for the channel catfish, synergism was not significant below copper-mercury concentrations of 50 µg/L.

Description of key information

A range of studies are available that relate to copper toxicity towards amphibians. Only nominal NOECs/EC50 values are available and these were therefore not used for the PNEC derivation.

Additional information

Data are available on a number of substances containing inorganic copper and read-across is justified on the basis that for the purposes of assessing the ecotoxicology of Copper (II) pyrophosphate (copper(2+) diphosphate) the chemical species of interest is copper. As such studies referring to soluble copper ions from any source are considered to be directly relevant to Copper (II) pyrophosphate. Copper (II) pyrophosphate is considered to contribute to copper toxicity in the environment and as such the data assessment and risk assessment focusses on the copper ion as the phosphate ion is not considered to be toxic.

 

Almost all tests gathered from literature on the effect of copper towards amphibians were performed on early life stages, in laboratory water (with low DOC concentration), with 4 days exposure times and according to standard guidelines. The results clearly show that amphibians (data were found for Xenopus laevis, Rana pipiens, Rana ridibunda, Rana hexadactyla, Rana Sphenocephala and Rana tigrina) are not sensitive towards copper. Indeed LC50 and NOEC/(L(E) C10 values respectively between 39 and 1,250 µg/L and between 40 and 100,000 µg/L were found.

Most of the studies report however EC50 values and test concentrations were not measured and therefore the data-reliability is low. These data were therefore not retained for the PNEC calculations. Fort et al., (2000) determined optimal copper concentration ranges for the early life stages of the amphibian X. Laevis: 1 to 10 µg Cu/L. Copper deficiency was observed at copper concentrations < 1 µg Cu/L.

 

Additional information:

A voluntary risk assessment report of copper and copper compounds has been submitted to the European Chemicals Agency by the European Copper Institute (June 2008). This report is based on the industry initiative to perform a voluntary risk assessment on a substance according to the mechanisms of the implementation of the Existing Substance Regulation (EEC) No 793/93 (ESR). The procedure was agreed by the 11thJoint Meeting of the Competent Authorities for the Implementation of Directive 67/548/EEC and ESR Regulation. Italy has been acting as a reviewing Member State for the substance and the risk assessment report has been reviewed by the Technical Committee on New and Existing Substances (TC NES) according to standard operational procedures of the Committee.

 

In accordance with the above mentioned European copper risk assessment, the environmental hazard assessment is based on tests carried out with soluble copper species. Studies reporting quantitative dose responses of Cu(II) ions, delivered from soluble copper compounds to aquatic organisms are used for this assessment.

 

The data presented are considered to be adequate and reliable for the purpose of defining an appropriate classification for the ecotoxicity of Copper (II) pyrophosphate in accordance with Regulation (EC) No.1272/2008 (EU CLP).