Research Product

Effluents from crude oil production platforms and tank batteries are commonly high-salinity, hydrocarbon-saturated wastewaters. These effluents, called brine, formation, or produced water, are usually discharged into the surrounding aquatic environment. Although discharges into freshwater areas have been restricted, there are continued discharges into brackish, estuarine, and marine areas. Acute effects were measured by determining the 96-h LC50 (concentration lethal to 50% of the animals exposed); LC50s ranged from 1.3% to 9.3%, based on volume:volume measurements. Concurrent "on-site" and laboratory tests were conducted with the same produced water samples to examine the effect of test location on toxicity. The 96-h LC50s for the "on-site" test and laboratory test were 5.1% and 1.3%, respectively. There was no indication that toxicity changed with time. The 7-Day Mysid Survival/Growth/Reproduction Study (U.S. EPA, 1986) and the ASTM Proposed Guidelines for Conducting a Life-Cycle Toxicity Test with Saltwater Mysids (ASTM, 1986) were used to evaluate possible chronic effects of one produced water sample analysis on mysids. For the 7-day test, reproduction was measured by the presence or absence of eggs in the females. For the 28-day test, reproductive effects were measured as number of young released.