2-(3-oxazolidinyl)ethyl methacrylate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 14, 2002 - August 31, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Test concentrations were verified by chemical analysis. Duplicate samples, 50 ml were taken from the control and each test concentration at 0 and 72 hours (fresh media) and 24 and 96 hours (expired media) for analysis.
Preliminary trials were conducted on the stability of the test material in aqueous solution as part of another GLP compliant HLS study (Huntingdon Life Sciences report number RAS 2581023216). Sealed vessels containing a known concentration of Oxazolidinyl ethyl methacrylate (OXEMA) were analysed at time 0 and after 24 hours under exposure to both light and dark conditions. Results showed the parent material degraded in both light and dark conditions. This indicated that Oxazolidinyl ethyl methacrylate (OXEMA) was subject to hydrolysis in solution.

Vehicle:

no

Details on test solutions:

Individual weighings of the test material were dispersed directly into the test medium to produce the test series, 10, 22,46, 100, 220 and 460 mg/l.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Source: Westacre Trout Farm, Norfolk

Acclimatisation: The stock of fish were obtained from the supplier on 15 February 2002 and acclimatised to test conditions from that date. Temperature remained within the range 15 to 17 degrees C and dissolved oxygen within the range 7.8 to 9.2 mgO2/l in the 14-day period immediately before the study with a 16 hour light: 8 hour dark photoperiod. The fish were fed daily to repletion with commercial fry pellet but food was not given during the 24 hour period immediately before exposure or during the exposure period itself. No medication was given during the acclimatisation period and no mortalities occurred in the 7 days before the test.

A representative sample of stock fish was measured at the start of the study. The mean standard length was 5.7 cm (SD = 0.5 cm) and the mean weight was 3.22 g (SD = 1.23 g).

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Remarks on exposure duration:

Fish were exposed to the test or control conditions for a period of 96 hours with daily batchwise renewal of the test medium

Hardness:

86 and 152 mgCaC0,/l

Test temperature:

15 degrees C

pH:

7.5-8.1

Dissolved oxygen:

8.5-8.6

Salinity:

total alkalinity: 84 mg/l

Conductivity:

370 microS/cm

Nominal and measured concentrations:

Nominal concentrations: 10, 22, 46, 100, 220 and 460 mg/l
Geometric mean measured concentrations: 8.6, 18, 35, 67, 123 and 224 mg/l

Details on test conditions:

Six test concentrations were prepared plus one control. Seven fish were added to each vessel. Fish were placed without conscious bias into glass aquaria containing prepared test medium. Each vessel contained 23 litres of medium to a depth of 19 cm (approximate dimensions of vessel: 25 x 46 x 25 cm). This provided a loading of 0.98g bodyweightllitre (static volume).

Throughout the study, supplementary aeration was provided through narrow bore glass tubes. A photoperiod of 16 hours light: 8 hours dark was employed with a 30 minute dawnldusk transition period. Daily records of pH, dissolved oxygen and temperature were kept for each control and test vessel. The fish were not fed during the 96 hour exposure period.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

91 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

18 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

behaviour

Details on results:

LC50 (0.25 hr) = > 460 mg/l [nominal], > 224 mg/l [geometric mean measured]
LC50 (2-4 hr) = 318 mg/l (95% CL = 242-419 mg/l) [nominal], 166 mg/l (95% CL = 133-208 mg/l) [geometric mean measured]
LC50 (24-96 hr) = 148 mg/l (95% CL = 111-199 mg/l) [nominal], 91 mg/l (95% CL = 72-114 mg/l) [geometric mean measured]
Highest test concentration resulting in 0% mortality: 100 mg/l [nominal], 67 mg/l [geometric mean measured]
Lowest test concentration with 100% mortality: 220 mg/l [nominal], 123 mg/l [geometric mean measured]
No-observed effect concentration: 22 mg/l [nominal], 18 mg/l [geometric mean measured]

Sub-lethal reactions to exposure (other than death) were hyperventilating, loss of equilibrium, lying on base of tank with spasmodic swimming, increased presence of faeces, increased pigmentation and swimming towards/at surface. These responses were observed among fish exposed to nominally 46, 100, 220 and 460 mg/l (equivalent to geometric mean measured concentrations of 35, 67, 123 and 224 mg/l).

Sublethal observations / clinical signs:

Table 1. Cumulative moratlity for rainbow trout exposed for 96 hours to OXEMA

Nominal concentration (mg/l)	Geometric mean measured concentration (mg/l)	Cumulative Mortality (initial population: 7)
		0.25 h	2 h	4 h	24 h	48 h	72 h	96 h
Control	ND	0/7	0/7	0/7	0/7	0/7	0/7	0/7
10	8.6	0/7	0/7	0/7	0/7	0/7	0/7	0/7
22	18	0/7	0/7	0/7	0/7	0/7	0/7	0/7
46	35	0/7	0/7	0/7	0/7	0/7	0/7	0/7
100	67	0/7	0/7	0/7	0/7	0/7	0/7	0/7
220	123	0/7	0/7	0/7	A/D	A/D	A/D	A/D
460	224	0/7	A/D	A/D	A/D	A/D	A/D	A/D

A/D = all dead

x/y = # of fish affected/number of fish surviving

Table 2: Observation on sub-lethal effects of rainbow trout exposed to OXEMA for 96 hours

Nominal concentration (mg/l)	Geometric mean measured concentration (mg/l)	Observation	Time (hours)
			0.25	2	4	24	48	72	96
Control	ND	NAD	7/7	7/7	7/7	7/7	7/7	7/7	7/7
10	8.6	NAD	7/7	7/7	7/7	7/7	7/7	7/7	7/7
22	18	NAD	7/7	7/7	7/7	7/7	7/7	7/7	7/7
46	35	NAD	7/7	7/7	7/7	7/7	7/7	7/7	4/7
		Slight increase in pigmentation	-	-	-	-	-	-	3/7
100	67	NAD	7/7	7/7	7/7	7/7	-	-	-
		Slight increase in pigmentation	-	-	-	-	7/7	-	-
		Increased pigmentation	-	-	-	-	-	7/7	7/7
		Swimming towards water surface	-	-	-	-	-	7/7	7/7
220	123	NAD	-	-	-	-	-	-	-
		Hyperventilating	7/7	-	-	-	-	-	-
		Slight loss of equilibrium	3/7	-	-	-	-	-	-
		Increased pigmentation	-	7/7	7/7	-	-	-	-
		Swimming towards water surface	-	7/7	-	-	-	-	-
		Swimming at water surface	-	-	7/7	-	-	-	-
		All fish dead	-	-	-	A/D	A/D	A/D	A/D
460	224	NAD	-	-	-	-	-	-	-
		Lying on side on bottom of tank with spasmodic swimming	7/7	-	-	-	-	-	-
		Large presence of faeces	Present
		All fish dead	-	A/D	A/D	A/D	A/D	A/D	A/D

NAD: no abnormalities detected

x/y: number of fish affected/number of fish surviving

-: not applicable

A/D: all dead

Validity criteria fulfilled:

yes

Conclusions:

The 96 hour LC50 value based on nominal concentrations for Oxazolidinyl ethyl methacrylate (OXEMA) with rainbow trout was 148 mg/l (equivalent to geometric mean measured concentrations of 91 mg/l).
The 'no-observed effect concentration' based on nominal concentrations for Oxazolidinyl ethyl methacrylate (OXEMA) with rainbow trout was 22 mg/l (equivalent to geometric mean measured concentrations of 18 mg/l).

Executive summary:

A study was performed to assess the acute toxicity of Oxazolidinyl ethyl methacrylate (OXEMA) to rainbow trout (Oncorhynchus mykiss) under static, daily renewal conditions. This study was conducted in accordance with the test guidelines EC Methods for Determination of Ecotoxicity Annex to Directive 92/69/EEC (O.J. No. L383A, 29.12.92) Part C, Method 1 and OECD Guideline for Testing of Chemicals No. 203.

Groups of seven juvenile fish were exposed to concentrations, nominally 10, 22, 46, 100, 220 and 460 mg/l, of Oxazolidinyl ethyl methacrylate (OXEMA) dissolved in water. Actual geometric mean measured test concentrations were 8.6, 18, 35, 67, 123 and 224 mg/l. Measured concentrations ranged from 96 - 101% of nominal values at 0 hours, 25 - 81% of nominal at 24 hours, 90 - 92% of nominal values at 72 hours and 48 - 74% of nominal values at 96 hours. Stability tests indicated the test material was subject to hydrolysis and therefore accounts for the losses experienced during the

24 hour period between renewal of test medium. Observations were made on the numbers of dead fish and the incidence of sub-lethal effects after 15 minutes and 2, 4, 24, 48, 72 and 96 hours exposure.

Environmental conditions, dissolved oxygen, temperature and pH, throughout the study remained within the ranges specified by the protocol.

The following values were determined based on geometric mean measured concentrations (0, 24, 48 and 96 hour analytical measurements):

Time (hours)                     LC50 (mg/l)                     95% confidence limits (mg/l)

0.25                                   >224                                   -

2-4                                    166                                   133 -208

24 - 96                               91                                    72 -114

Highest test concentration resulting in 0% mortality: 67 mg/l

Lowest test concentration resulting in 100% mortality: 123 mg/l

"No-observed effect concentration": 18 mg/l

The following values were determined based nominal concentrations:

Time (hours)                            LC50 (mg/l)                     95% confidence limits (mg/l)

0.25                                          >460                                   -

2-4                                          318                                   242 -419

24 - 96                                    148                                     111 -199

Highest test concentration resulting in 0% mortality: 100 mg/l

Lowest test concentration resulting in 100% mortality: 220 mg/l

"No-observed effect concentration": 22 mg/l

Description of key information

The key study is an OECD Guideline 203, EU Method C.1, GLP compliant study with Rainbow trout (Oncorhynchus mykiss).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

91 mg/L

Additional information

The acute aquatic toxicity of OXEMA was determined in rainbow trout (Oncorhynchus mykiss) in a static 96-hour test.

 

Groups of seven juvenile fish were exposed to concentrations, nominally to 10, 22, 46, l00, 220 and 460 mg/l, of OXEMA dissolved in water. Actual geometric mean measured test concentrations were 8.6, 18, 35, 67, 123 and 224 mg/l. Measured concentrations ranged from 96 -101% of nominal values at 0 hours, 25-81% of nominal at 24 hours, 90-92% of nominal values at 72 hours and 48-74% of nominal values at 96 hours. Stability tests indicated the test material was subject to hydrolysis and therefore accounts for the losses experienced during the 24 hour period between renewal of test medium. Observations were made on the numbers of dead fish and the incidence of sub-lethal effects after 15 minutes and 2, 4, 24, 48, 72 and 96 hours exposure.

 

The following values were determined based on geometric mean measured concentrations (0, 24, 48 and 96 hour analytical measurements):

 

Time (hours)                      LC₅₀(mg/1)                        95% confidence limits (mg/l)

0.25                                    >224                                                        -

2-4                                      166                                                    133-208

24- 96                                 91                                                      72- 114

 

Highest test concentration resulting in 0% mortality: 67 mg/l

Lowest test concentration resulting in 100% mortality: 123 mg/l

"No-observed effect concentration" : 18 mg/l

 

The following values were determined based nominal concentrations:

 

Time (hours)                      LC₅₀(mg/1)                        95% confidence limits (mg/l)

0.25                                    >460                                                        -

2-4                                      318                                                    242-419

24- 96                                 148                                                    111 –199

 

Highest test concentration resulting in 0% mortality: l00 mg/l

Lowest test concentration resulting in 100% mortality: 220 mg/l

"No-observed effect concentration": 22 mg/l