2-nitrotoluene

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

other: BUA report

Adequacy of study:

other information

Reliability:

other: BUA report

Rationale for reliability incl. deficiencies:

other: No reliability is given as this is a summary entry for the BUA report.

Principles of method if other than guideline:

BUA report

GLP compliance:

not specified

Specific details on test material used for the study:

- Analytical purity: not specified

Sublethal observations / clinical signs:

BUA report (1989):

 

The results of studies on the acute toxicity of o-nitrotoluene to fish are compiled in the following table:

Species	Duration [h]	Endpoint	Concentration [mg/l]	Reference
Brachydanio rerio	96	LC0	56.2	Bayer AG, 1986
	96	LC50	64.9
	96	LC100	75.0
Oryzias latipes	48	LC50	86.0	Yoshioka et al., 1986
	96	LC50	37.0	Canton et al., 1985 + 1982
	96	EC50 (mortality and immobility)	7.0	Bailey and Spanggord, 1983
Pimephales promelas	96	LC50	37.1	Bailey and Spanggord, 1983
	96	LC50	36.9	Hall and Kier, 1986
Leuciscus idus	48	LC0	11.0	Juhnke and Lüdemann, 1978
	48	LC50	29.0
	48	LC100	57.0
Poecillia reticulata	96	LC50	29.0	Canton et al., 1985 + 1982
	96	EC50 (mortality and immobility)	18.0	Canton et al., 1985

 

 

Executive summary:

BUA report (1989):

The results of studies on the acute toxicity of 2-nitrotoluene to fish were in the range of EC50 (96h): 29-64.9 mg/L.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Remarks:

Study meets basic scientific principles. Basic data given.

Principles of method if other than guideline:

- according to "Methods for Acute Toxicity Testing with Fish, Macroinvertebrates, and Amphibians", Ecological Research Series, EPA-66013-75-009
=> test temperature of 20°C is the only exception of this guideline

GLP compliance:

no

Specific details on test material used for the study:

- Name of test material (as cited in study report): 2-Nitrotoluene
- Analytical purity: not specified

Test organisms (species):

Pimephales promelas

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

26 ppm (as CaCO3)

Test temperature:

20°C

pH:

7.2 - 8.6

Details on test conditions:

alkalinity: 45 ppm (as CaCO3)
conductivity: 103 µmhos/cm

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

38 mg/L

Executive summary:

Pearson, 1979

The acute toxicity of the test item 2-nitrotoluene towards Pimephales promelas was tested in a static setup according to "Methods for Acute Toxicity Testing with Fish, Macroinvertebrates, and Amphibians", Ecological Research Series, EPA-66013-75-009 (the test temperature of 20°C was the only exception of this guideline). The following effect concentration was observed: LC50 (96h): 38 mg/L.

Reference 3

Endpoint:

fish embryo acute toxicity (FET)

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Remarks:

Study meets basic scientific principles. Basic data given.

Principles of method if other than guideline:

embryo-larval test

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (as cited in study report): 2-nitrotoluene
- Analytical purity: > 99%

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

7 d

Hardness:

250 mg/l as CaCO3

Test temperature:

25 ± 1 °C

pH:

8.2 ± 0.2

Details on test conditions:

- photoperiod: 12 h

Duration:

7 d

Dose descriptor:

LC50

Effect conc.:

40 mg/L

Remarks on result:

other: 95% CL: 29-54

Duration:

7 d

Dose descriptor:

EC50

Effect conc.:

28 mg/L

Remarks on result:

other: 95% CL: 10-100

Details on results:

CL=confidence limits

Sublethal observations / clinical signs:

- after 3 to 4 days eggs were hatched

Validity criteria fulfilled:

not specified

Executive summary:

Maas-Diepeveen, 1986

In a semi-static fish embryo acute toxicity test (test species: freshwater fish Danio rerio) the following effect concentrations were observed for 2-nitrotoluene: LC50 (7d): 40 mg/L and EC50 (7d): 28 mg/L.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Principles of method if other than guideline:

Method: other: Japanese Industrial Standard (JIS K 0102-1986-71) "Testing methods for industrial waste water"

GLP compliance:

not specified

Analytical monitoring:

not specified

Test organisms (species):

Oryzias latipes

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

88 mg/L

Validity criteria fulfilled:

not specified

Executive summary:

MITI, 1992

The acute toxicity of the test item 2-nitrotoluene towards Oryzias latipes was tested according to Japanese Industrial Standard (JIS K 0102-1986-71) "Testing methods for industrial waste water". The following effect concentration was observed: LC50 (48h): 88 mg/L.

Reference 5

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Remarks:

Only raw data available

Principles of method if other than guideline:

Method: other: Letale Wirkung beim Zebrabaerbling, UBA-Verfahrensvorschlag, Mai 1984, Letale Wirkung beim Zebrabaerbling Brachydanio rerio LC0, LC50, LC100, 48-96h

GLP compliance:

no

Specific details on test material used for the study:

- Analytical purity: not specified

Analytical monitoring:

no

Test organisms (species):

Leuciscus idus

Test type:

static

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

75 mg/L

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

56.3 mg/L

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

42.2 mg/L

Sublethal observations / clinical signs:

The LC50 relates to the geometric mean.

Executive summary:

Bayer (1986):

In an experimental study (static test) with an exposure period of 96 hours an LC50 value of 56.3 mg/l was obtained for the test organism Leuciscus idus. 

Reference 6

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Remarks:

Only raw data available

Principles of method if other than guideline:

Method: other: Letale Wirkung beim Zebrabaerbling, UBA-Verfahrensvorschlag, Mai 1984, Letale Wirkung beim Zebrabaerbling Brachydanio rerio LC0, LC50, LC100, 48-96h

GLP compliance:

no

Specific details on test material used for the study:

- Analytical purity: not specified

Analytical monitoring:

no

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Test type:

static

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

64.9 mg/L

Remarks on result:

other: geometric mean

Sublethal observations / clinical signs:

The LC50 relates to the geometric mean.

Executive summary:

Bayer (1986):

In an experimental study (static test) with an exposure period of 96 hours an LC50 value of 64.9 mg/l was obtained for the test organism Brachydanio rerio. 

Reference 7

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Remarks:

published data

Adequacy of study:

other information

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

supplementary published data, see justification for type of information

Justification for type of information:

Restrictions of the method are: - Test period not given (Personal communication Wang 2003: 96 h) - 4 fish used instead of at least 7 as recommended by the OECD TG 203 - Temperature during the test was higher (25 °C) than recommended 20-24 °C - Yeast is not a standard food for carp - Length of fish (2-6 cm) varied more than recommended by the OECD TG 203

Validity criteria fulfilled:

not specified

Remarks:

Restrictions of the method: - Test period not given (Personal communication Wang 2003: 96 h) - 4 fish used instead of at least 7 - Temperature during the test was higher (25 °C) than 20-24 °C - Yeast is not a standard food for carp - Length of fish 2-6 cm

Executive summary:

Yen, Jui-Hung; Lin, Kuo-Hsiung; Wang, Yei-Shung; Ecotoxicology and Environmental Safety; vol. 52; nb. 2; (2002); p. 113 - 116, (REAXYS data base):

Species: Ciprinus carpio

Method: 90 percent of the incubation medium was renewed with same concentration of title comp. after 48 h of incubation; 4 carp (2 to 6 cm in size) were introduced to each 10-L beaker containing 5 L of the different concentrations of the test chemical; the fish were fed with yeast; 25 °C; exposure in water pH 6.6, dissolved oxygen: 4.9 mg/L, hardness 215 mg/L as CaCO₃ with title comp. conc.; duplicate tests at each concentration level

In Table 4 of their publication, Yen et al. report the LC50 to be 0.396 mg/L. After request, one of the authors (Wang 2003) communicated that the reported values are below the observed values by a factor of 100. Thus, the correct LC50 is 36.9 mg/l. The test period is not given (Personal communication Wang 2003: 96 h).

Reference 8

Endpoint:

short-term toxicity to fish

Type of information:

other: EU Risk Assessment

Adequacy of study:

other information

Reliability:

other: EU Risk Assessment

Rationale for reliability incl. deficiencies:

other: No reliability is given as this is a summary entry for the EU RAR.

Principles of method if other than guideline:

EU Risk Assessment

GLP compliance:

not specified

Specific details on test material used for the study:

- Analytical purity: not specified

Sublethal observations / clinical signs:

EU Risk Assessment (2008):

 

Ramos et al., (1998) determined an EC50 for guppies (Poecilia reticulata) of 30.1 mg/l. Acute toxicity tests on fish were performed according to the OECD guideline 203, applying 12 h of photoperiod during the experiments. Animals were starved from 24 h before the tests. 5 concentration levels were tested with a dilution factor of 2.

 

Deneer et al., (1987) gave an LC50 = 32.9 mg/l for the chronic effects of 2-nitrotoluene to guppies in a 14-day test. Fish used in the toxicity experiments were male and female guppies, varying in age from two to three months, and in weight from 60 to 450 mg (mean fat content 8 ± 2%). Procedure for obtaining the 14d-LC50 values is according to Koenemann (1981). Water samples were taken regularly on, at least, four days during the experimental period, both before and after renewal of the solutions and analysed after hexane extraction. Upon analysis after 24 h of exposure, up to 40% of the compound added was converted into the corresponding aniline. This effect only occurred when fish were present in the solution. Nitroaryl compounds belong to the class of bioactivated chemicals, since they are reduced in vivo to highly active intermediates like arylnitroso-compounds and arylhydroxylamines. Therefore, it seems very likely that an adequate description of their toxicity involves their tendency to be reduced.

 

Bailey and Spanggord (1983) conducted ecotoxicity tests, with several individual substances, on fathead minnows (Pimephales promelas). The test fish were juveniles averaging 2.4 cm in total length and 0.28 g in weight. Fish were not fed for 24 h before or during any of the tests. As a general rule, test solutions were aerated only when DO dropped below 60% of saturation in the first 48 h of exposure or below 40% of saturation in the last 48 h of exposure. It is not indicated whether this is the case for 2-nitrotoluene, since aeration which could introduce a disturbing procedure that could lead to the disappearance of the test substance from the water. The 96h-LC50 was determined in 37.1 mg/l (ranging from 34.6 to 39.9 mg/l of 2 -nitorotoluene). Toxicity appears to be related to the ease of reduction of the nitro group to form nitroxy free radicals, which would then block life-supporting processes. Although reduction is believed to be an important pathway for detoxifying foreign nitro-bodies, the ease of formation of intermediate free radicals may overwhelm protective mechanisms available to the organisms.

 

In other experiment, carried out by Liu et al. (1983), it is provided a 96h-LC50 of 37.1 mg/l (ranging from 34.6 to 39.9 mg/l of 2-nitrotoluene). Acute toxicity tests were performed on P.promelas under static conditions. Fish were immature and no food was provided to the organisms during the test. These figures are in agreement with Bailey and Spanggord (1983) results.

 

Canton et al. (1985) performed a 24 -h short-term toxicity tests on Poecilia reticulata, in analogy with the OECD (1979) proposal, resulting in an LC50 of 29 mg/l and in a EC50 (behaviour) of 18 mg/l. To obtain an indication of the biological availability of the test compound, the decline of a non-aerated standardized medium was studied at room temperature. A recovery of 92% after 8 days was measured. Other short-term tests, performed with Oryzias latipes by the same authors, resulted in an LC50 of 37 mg/l and an EC50 (behaviour) of 7 mg/l. Test duration is not given in Canton et al. (1985) itself, but reference concerning the tests methods is made to other publications of Canton and his co-workers. In these publications exposure of fish in short-term tests was either 48 or 96 h. Test concentrations were adjusted 3 times a week.

 

Bayer (1986) also provides information within the IUCLID database regarding an exposure period of 96 hours in a static test, giving an EC50 of 65 mg/l on Brachidanio rerio. This information has not been considered for the assessment, since there was no possibility to check the original report.

 

Yoshioka et al. (1986) indicated an EC50 of 86 mg/l for Oryzia latipes, after an exposure period of 48 hours. A two days exposure time test was considered not assignable for the assessment.

 

Canton et al. (1985) referred some information on semi-chronic toxicity tests after an exposure period of 28 days resulted in both, an LC50 and EC50 (behaviour) of 9.4 mg/l. The NOEC (mortality and behaviour) was determined as 1.9 mg/l.

 

Juhnke and Luedemann (1978) also presented some data on Leuciscus idus, which have been considered as not assignable, since not enough information has been provided for its validation.

Executive summary:

EU Risk Assessment (2008):

Ramos et al., (1998) determined an EC50 for guppies (Poecilia reticulata) of 30.1 mg/l. Acute toxicity tests on fish were performed according to the OECD guideline 203, applying 12 h of photoperiod during the experiments. Animals were starved from 24 h before the tests. 5 concentration levels were tested with a dilution factor of 2.

Deneer et al., (1987) gave an LC50 = 32.9 mg/l for the chronic effects of 2-nitrotoluene to guppies in a 14-day test. Fish used in the toxicity experiments were male and female guppies, varying in age from two to three months, and in weight from 60 to 450 mg (mean fat content 8 ± 2%). Procedure for obtaining the 14d-LC50 values is according to Koenemann (1981). Water samples were taken regularly on, at least, four days during the experimental period, both before and after renewal of the solutions and analysed after hexane extraction. Upon analysis after 24 h of exposure, up to 40% of the compound added was converted into the corresponding aniline. This effect only occurred when fish were present in the solution. Nitroaryl compounds belong to the class of bioactivated chemicals, since they are reduced in vivo to highly active intermediates like arylnitroso-compounds and arylhydroxylamines. Therefore, it seems very likely that an adequate description of their toxicity involves their tendency to be reduced.

Bailey and Spanggord (1983) conducted ecotoxicity tests, with several individual substances, on fathead minnows (Pimephales promelas). The test fish were juveniles averaging 2.4 cm in total length and 0.28 g in weight. Fish were not fed for 24 h before or during any of the tests. As a general rule, test solutions were aerated only when DO dropped below 60% of saturation in the first 48 h of exposure or below 40% of saturation in the last 48 h of exposure. It is not indicated whether this is the case for 2-nitrotoluene, since aeration which could introduce a disturbing procedure that could lead to the disappearance of the test substance from the water. The 96h-LC50 was determined in 37.1 mg/l (ranging from 34.6 to 39.9 mg/l of 2 -nitorotoluene). Toxicity appears to be related to the ease of reduction of the nitro group to form nitroxy free radicals, which would then block life-supporting processes. Although reduction is believed to be an important pathway for detoxifying foreign nitro-bodies, the ease of formation of intermediate free radicals may overwhelm protective mechanisms available to the organisms.

In other experiment, carried out by Liu et al. (1983), it is provided a 96h-LC50 of 37.1 mg/l (ranging from 34.6 to 39.9 mg/l of 2-nitrotoluene). Acute toxicity tests were performed on P. promelas under static conditions. Fish were immature and no food was provided to the organisms during the test. These figures are in agreement with Bailey and Spanggord (1983) results.

Canton et al. (1985) performed a 24-h short-term toxicity tests on Poecilia reticulata, in analogy with the OECD (1979) proposal, resulting in an LC50 of 29 mg/l and in a EC50 (behaviour) of 18 mg/l. To obtain an indication of the biological availability of the test compound, the decline of a non-aerated standardized medium was studied at room temperature. A recovery of 92% after 8 days was measured. Other short-term tests, performed with Oryzias latipes by the same authors, resulted in an LC50 of 37 mg/l and an EC50 (behaviour) of 7 mg/l. Test duration is not given in Canton et al. (1985) itself, but reference concerning the tests methods is made to other publications of Canton and his co-workers. In these publications exposure of fish in short-term tests was either 48 or 96 h. Test concentrations were adjusted 3 times a week.

Bayer (1986) also provides information within the IUCLID database regarding an exposure period of 96 hours in a static test, giving an EC50 of 65 mg/l on Brachidanio rerio. This information has not been considered for the assessment, since there was no possibility to check the original report.

Yoshioka et al. (1986) indicated an EC50 of 86 mg/l for Oryzia latipes, after an exposure period of 48 hours. A two days exposure time test was considered not assignable for the assessment.

Canton et al. (1985) referred some information on semi-chronic toxicity tests after an exposure period of 28 days resulted in both, an LC50 and EC50 (behaviour) of 9.4 mg/l. The NOEC (mortality and behaviour) was determined as 1.9 mg/l.

Juhnke and Luedemann (1978) also presented some data on Leuciscus idus, which have been considered as not assignable, since not enough information has been provided for its validation.

Description of key information

For transported isolated intermediates according to REACh, Article 18, this endpoint is not a data requirement. However, data is available for this endpoint and is thus reported under the guidance of "all available data".

EU Risk Assessment (2008):

Ramos et al., (1998) determined an EC50 for guppies (Poecilia reticulata) of 30.1 mg/l. Acute toxicity tests on fish were performed according to the OECD guideline 203, applying 12 h of photoperiod during the experiments. Animals were starved from 24 h before the tests. 5 concentration levels were tested with a dilution factor of 2.

Deneer et al., (1987) gave an LC50 = 32.9 mg/l for the chronic effects of 2-nitrotoluene to guppies in a 14-day test. Fish used in the toxicity experiments were male and female guppies, varying in age from two to three months, and in weight from 60 to 450 mg (mean fat content 8 ± 2%). Procedure for obtaining the 14d-LC50 values is according to Koenemann (1981). Water samples were taken regularly on, at least, four days during the experimental period, both before and after renewal of the solutions and analysed after hexane extraction. Upon analysis after 24 h of exposure, up to 40% of the compound added was converted into the corresponding aniline. This effect only occurred when fish were present in the solution. Nitroaryl compounds belong to the class of bioactivated chemicals, since they are reduced in vivo to highly active intermediates like arylnitroso-compounds and arylhydroxylamines. Therefore, it seems very likely that an adequate description of their toxicity involves their tendency to be reduced.

Bailey and Spanggord (1983) conducted ecotoxicity tests, with several individual substances, on fathead minnows (Pimephales promelas). The test fish were juveniles averaging 2.4 cm in total length and 0.28 g in weight. Fish were not fed for 24 h before or during any of the tests. As a general rule, test solutions were aerated only when DO dropped below 60% of saturation in the first 48 h of exposure or below 40% of saturation in the last 48 h of exposure. It is not indicated whether this is the case for 2-nitrotoluene, since aeration which could introduce a disturbing procedure that could lead to the disappearance of the test substance from the water. The 96h-LC50 was determined in 37.1 mg/l (ranging from 34.6 to 39.9 mg/l of 2-nitorotoluene). Toxicity appears to be related to the ease of reduction of the nitro group to form nitroxy free radicals, which would then block life-supporting processes. Although reduction is believed to be an important pathway for detoxifying foreign nitro-bodies, the ease of formation of intermediate free radicals may overwhelm protective mechanisms available to the organisms.

In other experiment, carried out by Liu et al. (1983), it is provided a 96h-LC50 of 37.1 mg/l (ranging from 34.6 to 39.9 mg/l of 2-nitrotoluene). Acute toxicity tests were performed on P. promelas under static conditions. Fish were immature and no food was provided to the organisms during the test. These figures are in agreement with Bailey and Spanggord (1983) results.

Canton et al. (1985) performed a 24-h short-term toxicity tests on Poecilia reticulata, in analogy with the OECD (1979) proposal, resulting in an LC50 of 29 mg/l and in a EC50 (behaviour) of 18 mg/l. To obtain an indication of the biological availability of the test compound, the decline of a non-aerated standardized medium was studied at room temperature. A recovery of 92% after 8 days was measured. Other short-term tests, performed with Oryzias latipes by the same authors, resulted in an LC50 of 37 mg/l and an EC50 (behaviour) of 7 mg/l. Test duration is not given in Canton et al. (1985) itself, but reference concerning the tests methods is made to other publications of Canton and his co-workers. In these publications exposure of fish in short-term tests was either 48 or 96 h. Test concentrations were adjusted 3 times a week.

Bayer (1986) also provides information within the IUCLID database regarding an exposure period of 96 hours in a static test, giving an EC50 of 65 mg/l on Brachidanio rerio. This information has not been considered for the assessment, since there was no possibility to check the original report.

Yoshioka et al. (1986) indicated an EC50 of 86 mg/l for Oryzia latipes, after an exposure period of 48 hours. A two days exposure time test was considered not assignable for the assessment.

Canton et al. (1985) referred some information on semi-chronic toxicity tests after an exposure period of 28 days resulted in both, an LC50 and EC50 (behaviour) of 9.4 mg/l. The NOEC (mortality and behaviour) was determined as 1.9 mg/l.

Juhnke and Luedemann (1978) also presented some data on Leuciscus idus, which have been considered as not assignable, since not enough information has been provided for its validation.

 

BUA report (1989):

The results of studies on the acute toxicity of 2-nitrotoluene to fish were in the range of EC50 (96h): 29-64.9 mg/L.

 

Maas-Diepeveen, 1986:

In a semi-static fish embryo acute toxicity test (test species: freshwater fish Danio rerio) the following effect concentrations were observed for 2-nitrotoluene: LC50 (7d): 40 mg/L and EC50 (7d): 28 mg/L.

 

MITI, 1992:

The acute toxicity of the test item 2-nitrotoluene towards Oryzias latipes was tested according to Japanese Industrial Standard (JIS K 0102-1986-71) "Testing methods for industrial waste water". The following effect concentration was observed: LC50 (48h): 88 mg/L.

 

Pearson, 1979:

The acute toxicity of the test item 2-nitrotoluene towards Pimephales promelas was tested in a static setup according to "Methods for Acute Toxicity Testing with Fish, Macroinvertebrates, and Amphibians", Ecological Research Series, EPA-66013-75-009 (the test temperature of 20°C was the only exception of this guideline). The following effect concentration was observed: LC50 (96h): 38 mg/L.

 

Bayer (1986):

In an experimental study (static test) with an exposure period of 96 hours an LC50 value of 56.3 mg/l was obtained for the test organism Leuciscus idus. 

In an experimental study (static test) with an exposure period of 96 hours an LC50 value of 64.9 mg/l was obtained for the test organism Brachydanio rerio. 

 

Yen, Jui-Hung; Lin, Kuo-Hsiung; Wang, Yei-Shung; Ecotoxicology and Environmental Safety; vol. 52; nb. 2; (2002); p. 113 - 116, (REAXYS data base):

Species: Ciprinus carpio

Method: 90 percent of the incubation medium was renewed with same concentration of title comp. after 48 h of incubation; 4 carp (2 to 6 cm in size) were introduced to each 10-L beaker containing 5 L of the different concentrations of the test chemical; the fish were fed with yeast; 25 °C; exposure in water pH 6.6, dissolved oxygen: 4.9 mg/L, hardness 215 mg/L as CaCO3 with title comp. conc.; duplicate tests at each concentration level

In Table 4 of their publication, Yen et al. report the LC50 to be 0.396 mg/L. After request, one of the authors (Wang 2003) communicated that the reported values are below the observed values by a factor of 100. Thus, the correct LC50 is 36.9 mg/l. The test period is not given (Personal communication Wang 2003: 96 h).