Nitrilotrimethylenetris(phosphonic acid)

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995-10-18 to 1995-10-20

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Test procedure in accordance with national standard methods (based on ISO guideline) with acceptable restrictions. No data on GLP or analytical monitoring available. The test was conducted in a reputable and established laboratory according to an appropriate guideline, on the basis of this we can assign a reliability of 2 since no deviations from the guideline are stated even though the data presented is from a summary report only.

Qualifier:

equivalent or similar to

Guideline:

other: draft method ISO/CD 14669

Deviations:

no

Qualifier:

according to

Guideline:

other: Brixham Environmental Laboratory SOP BA207:03.

Deviations:

no

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

other: Acartia tonsa

Details on test organisms:

TEST ORGANISM

- Common name: Acartia

- Age at study initiation (mean and range, SD): 24.5 (+/-3) days

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

none

Hardness:

Not reported, assumed to meet guideline criteria.

Test temperature:

20 deg C (+/- 1)

pH:

Not reported, assumed to meet guideline criteria.

Dissolved oxygen:

Not reported, assumed to meet guideline criteria.

Salinity:

Not reported, assumed to meet guideline criteria.

Nominal and measured concentrations:

Nominal test concentrations were 56, 100, 180, 320, 560 and 1000 mg/l (as test substance).  

Details on test conditions:

TEST SYSTEM

- No. of organisms per vessel: 20

Reference substance (positive control):

yes

Remarks:

3,5, dichlorophenol

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

94 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: (95% CL 74.5-115)

Details on results:

- Mortality of control: 5%

Reported statistics and error estimates:

Not reported, assumed to meet guideline criteria.

Result expressed as nominal concentration. Properties of the test  substance and evidence from other studies (where concentrations were 

measured) indicate that nominal and measured concentrations are likely to be in good agreement.

Percentage mortality at each test concentration at the end of the test  (48 hours):

Table 1. Results

Nominal conc. (mg/L)	% mortality
	24 h	48 h
3,5 Dichlorophenol (1 mg/L)	40	100
Control	0	5
56	0	5
100	0	20
180	0	10
320	100	100
560	100	100
1000	100	100

24 LC-50 (95% confidence intervals): 240 (180-320) mg/L as test substance. Equivalent to 120 mg active acid/L.

Validity criteria fulfilled:

not specified

Remarks:

not enough data to validate, assumed to meet guideline criteria.

Conclusions:

A 48 h LC50 value of 94 mg/L (as active acid) has been determined for the effects of the test substance on mortality of the marine invertebrate Acartia tonsa.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was conducted according to an appropriate national standard method but full details are not available. It was not conducted under GLP and no analytical monitoring was carried out.

Qualifier:

according to

Guideline:

other: In house protocol: MIC Environmental Assessment Method for Conducting Acute Toxicity Tests with Daphnia magna (see note below)

Deviations:

no

Qualifier:

according to

Guideline:

other: US EPA (1975) Methods for acute toxicity tests with fish, macroinvertebrates and amphibians. EPA 660/3-75-009.

Deviations:

no

Qualifier:

equivalent or similar to

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

not applicable

Principles of method if other than guideline:

The In house protocol references Grueber and Adams (1980)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: For each test concentration the appropriate amount of the test compound was pipetted into 1L of dilution water and shaken vigorously for 1 min. The solution was then divided into 2 200 ml aliquots in triplicate beakers to provide the appropriate replication. The remaining 400 ml were used for 0 h DO, pH, alkalinity and hardness determinations.

- Controls: Just dilution water.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM

- Common name: water flea

- Source:  The daphnids used in the test were obtained from a laboratory culture at the MIC laboratory.

- Age at study initiation (mean and range, SD): <24 h

- Method of breeding: according to lab SOP

- Feeding during test: no


ACCLIMATION

- Acclimation period: not reported

- Acclimation conditions (same as test or not): not reported

- Type and amount of food: Daphnia were fed a mixture of Purina trout chow and alfalfa daily.

- Health during acclimation (any mortality observed): not reported

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

The alkalinity ranged from 236 to 304 mg/L and 250 to 300 mg/L in the low and high test concentration vessels respectively.

Test temperature:

Average temperature of 21.2 degrees C.

pH:

The pH in the control medium ranged between 7.2-8.4. The pH in the test media ranged between 2.0 and 8.2.

Dissolved oxygen:

The dissolved concentrations for the treatments were not reported due to measurement interference from the test materials. However, DO on the control water ranged from 6.2-9.4 mg/L. DO was measured by the Winkler titration method.

Nominal and measured concentrations:

Nominal test concentrations were 125, 250, 500, 1000 and 2000 mg/l as active acid

Details on test conditions:

TEST SYSTEM

- Test vessel: beaker

- Material, size, headspace, fill volume: 250 ml beakers containing 200 ml of test medium. 

- Aeration: no

- No. of organisms per vessel: 10

- No. of vessels per concentration (replicates): 3

- No. of vessels per control (replicates): 3



TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: well water from St. Peters, Missouri.

- Alkalinity: 303 mg/L CaCO3, hardness 297 mg/L CaCO3

- Culture medium different from test medium: not reported

- Intervals of water quality measurement:  DO, pH, alkalinity, hardness and temperature of test solutions were monitored at the initiation (control only) and termination of the test in the high, middle and low concentrations. 


OTHER TEST CONDITIONS

- Adjustment of pH: no

- Photoperiod: not reported

- Light intensity: not reported


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : immobility at 0, 24 and 48 h.


TEST CONCENTRATIONS

- Spacing factor for test concentrations: 2

- Range finding study

- Test concentrations: not reported

- Results used to determine the conditions for the definitive study: EC50 833 mg/L

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

125 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: immobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

297 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: immobility

Remarks on result:

other: 95% CL 262-342

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

545 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: immobility

Details on results:

- Mortality of control: 0%

Reported statistics and error estimates:

EC50 values and 95% confidence intervals calculated using an LC50 computer programme developed by Stephen et al (1978).   

Table 1. Summary of findings (average).

Nominal concentrations (mg/L)	Percent immobilisation
	24 h	48 h
Control	0	0
125	0	6.7
250	0	13.3
500	40	60
1000	100	100
2000	100	100

Result expressed as nominal concentration. Properties of the test substance and evidence from other studies (where concentrations were 

measured) indicate that nominal and measured concentrations are likely to be in good agreement.

The pH data suggest that the acidity of the higher concentration test solutions is likely to have contributed to the effects observed in the test.

Validity criteria fulfilled:

no

Remarks:

pH very low at the highest concentrations tested. However the reported EC50 value is high enough to determine toxicity that the test substance is of low intrinsic toxicity.

Conclusions:

A 48 h EC50 value of 297 mg active acid/L has been determined for the effects of ATMP acid on the immobility of the freshwater flea D. magna. The results should be treated with caution since the authors report that the mortalities seen are an effect of the pH of the test medium, rather than a reflection of true toxicity.

Description of key information

A 48 h EC50 value of 297 mg/L (as active acid) has been determined for the effects of ATMP-H on mobility of the freshwater flea Daphnia magna. 

A 48 h LC50 value of 94 mg/L (as active acid) has been determined for the effects of ATMP-H on mortality of the marine invertebrate Acartia tonsa.

Key value for chemical safety assessment

EC50/LC50 for freshwater invertebrates:

297 mg/L

EC50/LC50 for marine water invertebrates:

94 mg/L

Additional information

The studies reflect the lowest reliable values that are available for this endpoint.