Pyridine-2-thiol 1-oxide, sodium salt

Short-term toxicity to aquatic invertebrates

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.022 mg/L

Additional information

See Tables 6.1.3.1, 6.1.3.2, 6.1.3.3, and 6.1.3.4 for summaries on the acute toxicity to invertebrates of sodium pyrithione and its metabolites.

Acute studies on invertebrates indicate that NaPT is toxic. The LC₅₀values range from 0.022 to 0.15 mg NaPT/L.The lowest NOEC for these studies was 0.011 mg NaPT/L.

 

Further, acute toxicity studies in fish for the major metabolites indicate that the most toxic substance is Pyrithione disulphide with a NOEC of 0.006 mg/L, to daphnia magna. Pyrithione disulphide is very short lived in the environment and the most relevant degradant of NaPT is Pyridine sulphonic acid (PSA). The NOEC for PSA is 51.1 for the eastern oyster.

Table 6.1.3.1:           Acute toxicity of NaPT to invertebrates

Guideline / Test method	Species	Endpoint / Type of test	Exposure		Results [mg/L]			Remarks	Reference
			design	duration	NOEC	LC50	LC100
OECD 202. 92/69/EEC, C.2.	Daphnia magna	Immobilis-ation	Static	48 hours	0.02	0.15	1.3		6.1.3.001 ESPTF 7041-201 Smith et al (1994)
U.S. EPA-FIFRA, Guideline 72-2	Daphnia magna	Immobilis-ation	Flow through	48 hours	0.011	0.022	>0.037		6.1.3.002 ESPTF 7041-202 Smith et al (1994)

Table 6.1.3.2:    Acute toxicity of Pyridine-N-oxide-2-sulfonic acid to invertebrates

Guideline / Test method	Species	Endpoint / Type of test	Exposure		Results [mg/L]			Remarks	Reference
			design	duration	NOEC	LC50	EC50
US EPA-  72-2	Daphnia magna	Immobility and mortality	Flow-through	48 hours	127		>127		6.1.3.005 EZPTF 7041-211 Ward TJ, Kowalski PL, Boeri RL (1994)
US EPA – 72-3(b)	Mysid   Mysidopsis bahia	Mortality	Static	96 hours	32.2	71.3			6.1.3.007 EZPTF 7041-214 Ward TJ, Kowalski PL, Boeri RL (1994
US EPA	eastern oysterCrassostrea virginica	Shell growth	Flow-through	96 hours	35.6		99.2		6.1.3.014 EZPTF 7041-217 Boeri RL, Kowalski PL, Ward TJ (1994)

 

Table 6.1.3.3:    Acute toxicity of Pyridine Sulphonic acid to invertebrates

Guideline / Test method	Species	Endpoint / Type of test	Exposure		Results [mg/L]			Remarks	Reference
			design	duration	NOEC	LC50	EC50
US EPA-  72-2	Daphnia magna	Immobility and mortality	Flow-through	48 hours	122		>122		6.1.3.006 EZPTF 7041-212 Ward TJ, Kowalski PL, Boeri RL (1994)
US EPA – 72-3(b)	Mysid –   Mysidopsis bahia	Mortality	Flow-through	96 hours	51.9	71.6			6.1.3.008 EZPTF 7041-215 Ward TJ, Kowalski PL, Boeri RL (1994)
US EPA	eastern oysterCrassostrea virginica	Shell growth	Flow-through	96 hours	51.1	85.6		Key study	6.1.3.009 EZPTF 7041-218 Boeri RL, Kowalski PL, Ward TJ (1994)

 

Table 6.1.3.4:    Acute toxicity of 2,2’-(pyridyl-N-oxide) disulphide to invertebrates

Guideline / Test method	Species	Endpoint / Type of test	Exposure		Results [mg/L]			Remarks	Reference
			design	duration	NOEC	LC50	EC50
US EPA-  72-2	Daphnia magna	Immobility and mortality	Flow-through	48 hours	0.006		0.013		6.1.3.011 EZPTF 7041-210 Ward TJ, Magazu JP, Boeri RL (1995)
US EPA- 72-3(b)	Mysidopsis bahia	Mortality	static	96 hours	0.004	0.0064			6.1.3.012 EZPTF 7041-213 Ward TJ, Magazu JP, Boeri RL (1995)
US EPA – 72-3(c)	eastern oysterCrassostrea virginica	Shell growth	Flow-through	96 hours	0.110		0.16		6.1.3.013 EZPTF 7041-216 Ward TJ, Magazu JP, Boeri RL (1995)

  The information contained within this robust summary document comes from studies which are in the ownership of Arch Chemicals Inc. and which are protected in several regions globally. This information may not be used for any purpose other than in support of the Chemical safety Report submitted by Arch Chemicals Inc. under RegulationEC 1907/2006.