ASTM D6081 Aquatic Toxicity Testing of Lubricants: Sample Preparation and Results Interpretation 

Scope:

ASTM D6081 elucidates the preparation of lubricants or lubricant components, of any volatility, for acute and chronic aquatic toxicity assessments. It can also be used with additives when after being mixed into a carrier fluid, the concentration is close to that of the fully prepared lubricant. Acute or chronic aquatic toxicity testing using fish, big invertebrates, or algae can be undertaken in freshwater or saltwater using samples produced in line with ASTM D6081. 

Procedure:

In ASTM D6081 test organisms were inserted in the test solutions within 60 min after preparation. When test organisms are added, the test exposure time begins. The toxicity test exposure loads are determined by the loading rate of test materials. Acute and chronic investigations are repeated every 24 or 48 h with various Water Accommodated Fraction (WAF) or Water Soluble Fraction (WSF) preparations. At least 75 % of the test solution is replenished with each renewal.

Specimen Size:

Each vessel’s stirring speed should be set between 1000–1500 rpm, resulting in a 12–20 mm vortex within the cylinder (5–10 % of cylinder height).

Data:

The 95 % confidence limits for the LLXX, ILXX, or ELXX are determined using nominal loading rates.

Where:

LLXX= lethal load XX

ILXX= inhibition load XX

ELXX= effect load XX

Conclusion:

ASTM D6081 covers the processes for preparation and interpretation of lubricants or their components for toxicity testing in aquatic systems.