D-glucitol monolaurate

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

ISO 10253 (Water quality - Marine Algal Growth Inhibition Test with Skeletonema costatum and Phaeodactylum tricornutum)

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: US EPA (1985) Methods for measuring the acute toxicity of effluents to freshwater and marine organisms. EPA/600/4-85/013

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Sorbitan laurate

EC Number:

215-663-3

EC Name:

Sorbitan laurate

Cas Number:

1338-39-2

Molecular formula:

C18H34O6

IUPAC Name:

1,4-anhydro-6-O-dodecanoyl-D-glucitol

Constituent 2

Reference substance name:

931-434-7

EC Number:

931-434-7

IUPAC Name:

931-434-7

Details on test material:

- Name of test material (as cited in study report): sorbitan monolaurate
- Physical state: liquid
- Analytical purity: no data

Note: Due to analytical test results the substance is defined as UVCB. For further details see IUCLID Chapter 1.2.

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test solutions were prepared by the direct addition of the required nominal weights or volumes to seawater followed by gentle stirring for approximately 20 hours followed by a settling period of approximately one hour. After this settling period, the middle phase of the preparation was siphoned, avoiding incorporation of undissolved particles, if present.

Test organisms

Test organisms (species):

Skeletonema costatum

Details on test organisms:

TEST ORGANISM
- Source: stock laboratory cultures
- Method of cultivation: pre-cultures in the exponential growth phase were prepared from stock laboratory cultures by inoculating nutrient medium
(ISO medium) to a cell density of approximately 10000 cells per mL. The precultures were incubated at approximately 20 °C under constant illumination for at least four days

ACCLIMATION
- Culturing media and conditions: same as in test

Study design

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

19.3 - 21.3°C

pH:

7.68 - 8.21

Nominal and measured concentrations:

Nominal: 3.2, 10, 32, 100, 320 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: closed (loosely covered with aluminium foil caps)
- Material, size, fill volume: 100 mL borosilicate glass conical flasks, containing 80 mL test medium
- Initial cells density: 9975 cells/mL
- No. of vessels per concentration: 2
- No. of vessels per control: 4

GROWTH MEDIUM
- Standard medium used: yes, ISO medium

OTHER TEST CONDITIONS
- Light intensity: 4 x 40W tubes at a distance of approximately 40 cm over the test area

EFFECT PARAMETERS MEASURED :
- Determination of cell concentrations: cell number was determined using either a haemocytometer or Sedgewick-Rafter chamber, depending on cell number present

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3.2
- Range finding study: 19-23 October 1998
- Test concentrations: 1, 10, 100 and 1000 mg/L
- Results used to determine the conditions for the definitive study: effects on algae growth were observed for all test concentrations (although very slight in the lowest concentration)

Reference substance (positive control):

yes

Remarks:

3,5 Dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

17.89 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

growth rate

Remarks on result:

other: 95%CL: 17.68-18.1

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOELR

Effect conc.:

>= 10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

growth rate

Details on results:

- EL50 values after 24 and 48 h were 9.41 and 10.93 mg/L, respectively.
- Control growth rate 1.14 1/d
- Initially the test substance appeared to be soluble at 1000 mg/L, but whilst preparing the stock for testing, floating particles were observed.

Results with reference substance (positive control):

72h-EC50 of 3,5 Dichlorophenol: 3.21 mg/L

Reported statistics and error estimates:

The resulting values represent proportional reduction in growth rate, and are thus in a form from which an EL50 value can be calculated. The EL50
for each time interval was calculated using the moving average-angle method (US EPA 1985) (expressed in mg/L)

Any other information on results incl. tables

Table 1. Calculated growth rates and effects after 24, 48 and 72 h

Treatment	24 h			48 h			72 h
	Rep growth	Rep effect	Conc effect	Rep growth	Rep effect	Conc effect	Rep growth	Rep effect	Conc effect
320a	0.00	1.00	1.00	0.00	1.00	1.00	0.00	1.00	1.00
320b	0.00	1.00		0.00	1.00		0.00	1.00
100a	0.00	1.00	1.00	0.00	1.00	1.00	0.00	1.00	1.00
100b	0.00	1.00		0.00	1.00		0.00	1.00
32a	-0.91	1.00	1.00	0.03	0.98	1.00	0.00	1.00	1.00
32b	-0.69	1.00		-0.14	1.00		0.00	1.00
10a	1.34	0.15	0.23	1.63	-0.13	0.06	1.30	-0.14	-0.13
10b	1.07	0.32		1.07	0.26		1.28	-0.13
3.2a	1.13	0.28	0.13	1.28	0.11	0.19	1.16	-0.02	-0.08
3.2b	1.59	-0.02		1.04	0.28		1.30	-0.14