Isopropanol in freshwater and marine water

​​Toxicant default guideline values for protecting aquatic ecosystems

October 2000

Extracted from Section 8.3.7 ‘Detailed descriptions of chemicals’ of the ANZECC & ARMCANZ (2000) guidelines.

The default guideline values (previously known as ‘trigger values’) and associated information in this technical brief should be used in accordance with the detailed guidance provided in the Australian and New Zealand Guidelines for Fresh and Marine Water Quality.

Description of chemical

Isopropyl alcohol or isopropanol (CAS 67-63-0) is a useful alcohol cleaner (e.g. for electrical parts) and a raw material for chemical synthesis. It has very low aquatic toxicity in the g/L range but can contribute to depression of dissolved oxygen (DO) in water bodies. It is miscible in water and has a low log Kow.

Aquatic toxicology

Freshwater fish: two species, 48 to 96-hour LC50, 4200 to 11,130 mg/L.

Freshwater insects: one species, Chironomus riparius, 48-hour LC50, 12,500 mg/L (12.5 g/L).

Freshwater ciliate: one species, Tetrahymena pyriformis, 48-hour LC50 population growth, 5830 mg/L.

Marine crustacean: one species, Crangon crangon, 48 to 96-hour LC50, 1150 to 1400 mg/L.


There were very few data to derive figures for isopropanol, so factors of 1000 were applied to give trigger values. A freshwater low reliability trigger value of 4200 µg/L (4.2 mg/L) was derived. A marine low reliability trigger value of 1200 µg/L (1.2 mg/L) was derived. These should only be used as indicative interim working figures.


ANZECC & ARMCANZ 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Australian and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand, Canberra.