Toxicity test procedures forHyalella azteca, and chronic toxicity of cadmium and pentachlorophenol toH. azteca, Gammarus fasciatus, andDaphnia magna

Abstract

Survival, growth, and reproduction of Hyalella azteca were determined under various test conditions. Reproduction by a cohort begins when the amphipods are 5 to 6 weeks old, peaks at 8 to 12 weeks, and then declines due to continuing adult mortality. Full life-cycle tests can be completed in 12 to 14 weeks at 25 degrees C. Reproduction is poor when only artificial plastic substrate is provided. A substrate of cotton gauze results in dramatic improvements in both reproduction and growth. Better reproduction can be obtained by culturing the amphipods in some sediments, but this makes weekly enumeration difficult. Increased mortality during chronic exposure to cadmium was observed at 1 microgram/L for H. azteca and 3.2 micrograms/L for Gammarus fasciatus. Reproduction during longer exposure was not reduced at concentrations lower than those causing increased mortality within six weeks. Chronic toxicity of pentachlorophenol was observed at 100 micrograms/L for both species. Chronic toxicity to Daphnia magna was similar to that of the amphipods for cadmium, but lower for pentachlorophenol. Amphipods are at least as sensitive as Daphnia to a variety of toxicants during chronic exposure.

Comparison of the relative sensitivity of three benthic invertebrates to copper-contaminated sediments from the Keweenaw Waterway

“…The H. azteca were from static culture tanks, approximately 2 1 in volume, which contained sterile cotton gauze as a substrate (Borgmann et al, 1989). The H. azteca cultures were fed three times each week with 10 ml of a yeast-cerophylltrout food mixture (U.S. Environmental Protection Agency 1989) and 20 ml of diatoms (Synedra sp.…”

“…Although H. azteca, C. tentans and L. variegatus have been used to evaluate the toxicity of single chemicals or contaminated sediments (Bailey & Liu, 1980;Adams et al, 1985;Ewe11 et al, 1986;Ziegenfuss et al, 1986;Giesy et al, 1988;Borgmann et al, 1989Borgmann et al, , 1991Nebeker etal., 1989aNebeker etal., , 1989bIngersoll & Nelson 1990;Ankley etal., 1991aAnkley etal., , 1991bCall etal., 1991;Carlson et al, 1991;Phipps et al, 1993), few studies have compared the relative sensitivity of these epibenthic/benthic species. Information on the relative sensitivity of organisms proposed as standard test species for sediment toxicity testing is critical to acceptance within a regulatory framework.…”

Effect of growth on reproduction in the freshwater amphipod, Hyalella azteca (Saussure)

“…H. azteca is widely accepted and used as a bioassay test organism for freshwater sediments (USEPA/USACE, 1994 ;USEPA, 1994 ;ASTM, 1993 ;APHA AWWA WPCF, 1985) . Numerous toxicological studies have been conducted with this species (Borgmann et al ., 1989 ;Brasher & Ogle, 1993 ;Collyard et al ., 1994 ;Ingersoll & Nelson, 1990).…”

Accumulation, regulation and toxicity of copper, zinc, lead and mercury in Hyalella azteca

“…Hyalella azteca is an ideal organism for the assessment of metal toxicity because it is very sensitive to metals (Borgmann et al, 1989b), is found throughout most of North America, is easy to identify, and is amenable to laboratory culture and toxicity testing. It is a benthic organism and can be used for testing the toxicity of both waterborne contaminants and sediments (Borgmann & Munawar, 1989).…”