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Ecotoxicological information

Toxicity to terrestrial plants

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The minimum EC25 value calculated during a study with diflufenzopyr sodium salt was 0.00027 lb A.E./A for turnip shoot weight during the vegetative vigor phase. The lowest NOEC was determined during vegetative vigor phase was determined to be 0.00060 lb A.E./A (tomato, turnip, root weight, shoot length, shoot weight and root weight).

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In the study the toxicity of the test substance to ten plant species during three life stages (seed germination, seedling emergence and vegetative growth) was investigated in accordance with EPA Subdivision J Guidelines, 122-1 and 123 -1. The plant species tested included four monocotyledons: corn (Zea mays), oat (Avena sativa), onion (Allium cepa) and perennial ryegrass (Lolium perenne); and six dicotyledons: cabbage (Brassica oleracea), cucumber (Cucumis sativus), lettuce (Lactuca sativa), soybean (Glycine max), tomato (Lycopersicon esculentum) and turnip (Brassica rapa). Toxic effects were quantified during each phase of the study and are reported as EC25 and EC50 values, including a No-Observed-Effect Concentration (NOEC) for each species. The minimum EC25 value calculated during this study was 0.00027 lb A.E./A for turnip shoot weight during the vegetative vigor phase. This value is approximately 0.14% of the maximum recommended application rate of 0.20 lb A.E./A for the test substance. The lowest EC25 value during the seed germination phase was determined to be 0.0031 lb A.E./A for cabbage radicle length. The lowest EC25 value during the seedling emergence phase was determined to be 0.0014 lb A.E./A for lettuce shoot length.

The correspondent NOEC values were determined to be: 0.00060 lb A.E./A (turnip, vegetative vigor phase, shoot weight), 0.0025 lb A.E./A (cabbage, seed germination phase, radicle length), 0.00034 lb A.E./A (lettuce, seedling emergence phase, shoot length).

The lowest NOEC was determined during seed germination phase was determined to be 0.0025 lb A.E./A (cabbage, radicle length). The lowest NOEC was determined during seedling emergence phase was determined to be 0.00034 lb A.E./A (lettuce, shoot length).

The lowest NOEC was determined during vegetative vigor phase was determined to be 0.00060 lb A.E./A (tomato, turnip, root weight, shoot length, shoot weight and root weight).