cis-4-[3-(p-tert-butylphenyl)-2-methylpropyl]-2,6-dimethylmorpholine

Endpoint summary

Description of key information

Fenpropimorph = active substnace = a.s.

AQUATIC TOXICITY

Short-term toxicity for fish and invertebrates

Based on the acute toxicity data, Fenpropimorph is toxic to fish and invertebrates (Daphnia). The most sensitive species for fish was the blue gill, Pimephales promelas, with an LC₅₀-value of 1.4 mg a.s./L. For the invertebrates the lowest EC50- value of 2.24 mg a.s./L

 

Long-term toxicity for fish and invertebrates

Long-term studies on invertebrates (21 d) resulted in a NOEC-value of 2.2 µg a.s./L (time measured mean). In addition, an ELS-study with fish was performed resulting in the most sensitive NOAEL-value of 0.00016 mg a.s./L.

 

Toxicity to aquatic algae and Cyanobacteria

The EC₅₀ -value (growth rate) of green algae was determined to be > 1.0 mg a.s./L. Further a NOEC (growth rate) of 0.058 mg a.s./L was determined.

 

Toxicity to microorganism

The EC20 in the activated sludge respiration inhibition test is >100 mg/l. Disturbances in the biodegradation process of activated sludge are not to be expected if the test substance is correctly introduced into adapted wastewater treatment plants at low concentrations. Concentration control analysis was carried out in all aquatic systems, results are mostly reported based on analytically measured concentrations.

 

In environmental studies a major metabolite, fenpropimorph-acid was identified in aquatic test systems at significant concentrations, hence fenpropimorph-acid was subject of ecotoxicological studies on aquatic organisms. The metabolite proved to be by far less toxic on O. mykiss, D. magna, and P. subcapitata, compared to the active substance. All LC/EC₅₀-values were > 100 mg/L.

Additional information

Table 1: Summary of results on effects of Fenpropimorph and the metabolite fenpropimorph-acid on aquatic organisms

 

Test species	Test system	Result [mg a.s./L] EC/LC50	Result [mg a.s./L] NOEC/LC0	Reference
Fenpropimorph
O. mykiss	static - 96 h	> 2.41 < 4.72 *	0.5	Zok,1999/11539
L. macrochirus	static - 96 h	> 1.74 < 3.05 *	0.263	Zok, 1999/11840
A. gueldenstaedti	Semi-static - 96 h	> 2.15 < 4.64 *	0.215	Munk, 1998/10494
C. carpio	Static - 96 h ^6)	~ 3.16	0.681	Gelbke, Munk, 1979/10037
P. promelas	Static - 96 h	1.4 *	0.4	Zok, 2005/1016456
D. rerio	Static - 96 h	3.1 *	0.7	Zok, 2005/1016457
O. mykiss	flow-through – 21 d	1.5 *	0.1	Dommröse, 1989/0571
O. mykiss	ELS - 94 d	--	0.00016 ^1)	Munk, 1995/10517
O. mykiss	ELS - 49 d	--	0.003	Zok, 2005/1005782
D. magna	static – 48 h	2.24	1	Jatzek, 1999/11534
D. magna	flow-through - 21 d	0.42	0.082	Dommröse 1989/10174
C. riparius	static – 20 d	--	0.125	Dohmen, 1994/11731
P. subcapitata	static – 72 h	> 1.0 ^2)	0.058 ^3)	Kubitza, 2000/1000097
L. idus	Microcosm (28 days), static	--	0.012	Dohmen, 2002/1011545
Metabolite Fenpropimorph-acid (BF 421-2)
O. mykiss	static - 96 h	> 100	100	Munk, 1998/10035
D. magna	static – 48 h	> 100	100	Dohmen, 1997/10143
P. subcapitata	static – 72 h	> 100 ^2) 3)	25	Dohmen, 1997/11036

1) NOAEL,      2) = E_rC₅₀;          3) = E_rC₁₀           4) = E_bC₅₀;         5) = E_bC₁₀      
6) old study without GLP, however according to standard test design
* results based on mean measured concentrations