Toxicity of Copper-Spiked Sediments to Tubifex Tubifex (Oligochaeta, Tubificidae): Comparison of the 28-Day Reproductive Bioassay With an Early-Life-Stage Bioassay

Abstract

Abstract-Two sediment bioassay methods using Tubifex tubifex (Müller, 1774) as the test species were compared. The first was an adult reproduction test, the second an early-life-stage survival test. The duration of both bioassays is 28 d and the amount of work required was similar; they may be useful alternatives to each other in different circumstances (e.g., the early life stage bioassay could be carried out with smaller volumes of sediment). The two bioassays were performed simultaneously on copper-spiked sediments. Sediments from two freshwater and two terrestrial sites were used; five separate, nonsimultaneous experiments were performed, one for each sediment or soil and a further experiment with soil with a food supplement. In the adult bioassay, there were large differences in the production of cocoons, eggs, and young among the control treatments of the five experiments. There were also major differences in the NOEC (no-observed-effect concentration) and LOEC (lowest-observed-effect concentration) for copper between the tested substrates. The early life stage bioassay appears to be less sensitive to copper toxicity than the adult reproductive bioassay since NOECs and LOECs are higher for early survival than for the most sensitive endpoints of the adult bioassay in three experiments out of five.

Recommendations for the assessment of TNT toxicity in sediment

“…Future research is necessary to investigate this method of dose estimation and generate the data necessary to definitively assess the sublethal toxicity of TNT. Reproduction of T. tubifex exposed to the 1-and 8-d-aged control and solvent control sediments was similar to that of previous experiments with healthy sediments in our laboratory and those reported in the literature [19][20][21]36]. However, T. tubifex exposed to the 29-d-aged control and solvent control sediments were the least reproductive and statistically distinct from the other controls (LSD grouping: reproduction in 1-daged sediment ϭ reproduction in 8-d-aged sediment Ͼ reproduction in 29-d-aged sediment).…”

“…Tubifex tubifex is commonly used for sediment testing because this species is easily cultured, is tolerant of a wide variety of sediment types and abiotic conditions, and is a relevant sentinel because of its ecological importance and wide geographic distribution [19–22]. Tubifex tubifex is ideal for examining chemical bioavailability and toxicity in sediments because the species maintains continuous intimate contact with sediment and actively ingests sediment or sediment constituents, enabling contaminant uptake via dermal and intestinal exposure routes [20]. To begin each of the three toxicity tests, four adult 9‐ to 10‐week‐old T. tubifex were added to each replicate.…”

Influences of sediment geochemistry on metal accumulation rates and toxicity in the aquatic oligochaete Tubifex tubifex

“…But, reductions in worm biomass may be also explained by the high autotomy percentage detected in MN at day 10. Offspring production (TYG or YGAD) was the most sensitive endpoint, as has been previously reported by other authors for T. tubifex (Gillis et al, 2002;Maestre et al, 2007;Méndez-Fernández et al, 2013;Reynoldson et al, 1991;Vecchi et al, 1999). According to Reynoldson and Day (1998) criteria for determining toxicity in near shore sediment of the Great lakes regarding young production in T. tubifex are: non-toxic: >9.9 YGAD, potentially toxic: 9.8-0.8 YGAD, and toxic: <0.8 YGAD.…”

Review and comparison of available testing approaches and protocols for testing effects of chemicals on sediment‐dwelling organisms with potential applicability to pesticides

“…see ASTM E1706, 2010), the number of cocoons (empty and with embryos), small young (retained by 250 um mesh sieve) and larger young (retained on a 500µm mesh sieve) can be counted and included as test endpoints (e.g. Vecchi et al 1999). Lumbriculus variegatus is the main species recommended in OECD guideline 225 for assessment of prolonged exposure to sediment-associated contaminants.…”

“…for L.variegatus Bailey & Liu,1980, Phipps et al 1993, Kukkonen & Landrum 1994, Ingersoll et al 1995, Dermott & Munawar 1996, Leppänen & Kukkonen 1998a-c, ASTM International 2000, Conrad et al 2000, U.S. EPA 2000, Brust et al 2001, Nikkilä et al 2003, Landrum et al 2004Croce et al 2005, Egeler et al 2005 and (e.g. for T. tubifex, Reynoldson et al 1991 andVecchi et al 1999) and both species have also been recommended for use in standard test guidelines (e.g. for both species ASTM, 2010and OECD 225, 2007and US EPA, 2000 specifically references for L. variegatus, as does OECD 315, 2008 although other species may be used).…”