Long-term sediment bioassay of lead toxicity in two generations of the marine amphipod Elasmopus laevis, S.I. Smith, 1873.

Sediments are evaluated for toxicity by measuring mortality in a single cohort of amphipods in either acute (10-d) or chronic (28-d) bioassays. This investigation differed from conventional bioassays in four ways: Sublethal effects (fecundity) were estimated; the testing period was 60+ d; two successive generations were examined; and Elasmopus laevis Smith, 1873, amphipods were employed. Four test sediments were created between 58 and 424 microg/g of lead using the 30-microg/g whole-sediment as the control.

Effect of sequentially combining methanol and acetic acid on the performance of biological nitrogen and phosphorus removal.

A sequentially combined carbon (SCC) source using methanol and acetic acid was investigated for biological nitrogen and phosphorus removal in a wastewater treatment process consisting of an anoxic zone, an oxic zone and a final settling tank. The anoxic zone was divided into two separate anoxic zones to feed methanol in the first anoxic zone and acetic acid in the second anoxic zone. Methanol and acetic acid, each as the sole carbon source, were also tested for comparison.