Earthworm toxicity test

Callahan, C.A., L.K. Russell, and S.A. Peterson. 1985. A comparison of three earthworm toxicity test procedures for the assessment of environmental samples containing hazardous wastes. Biol. Fertil. Soils 1 195-200. 

Kuperman, R.G., Simini, M., Phillips, C.T. and Checkai, R.T. (1999) Comparison of malathion toxicity using enchytraeid reproduction test and earthworm toxicity test in different soil types. Pedobiologia, 43, 630-634. 

Spurgeon, D.J. and Hopkin, S.P. (1995) Extrapolation of the laboratory based OECD earthworm toxicity test to metal contaminated field sites. Ecotoxicology, 4, 190-205. 

Requirements with regard to plant toxicity are identical for EN, ISO and ASTM norms. The only deviating standard is AS 4736-2006, which also requires an earthworm toxicity test as well as two plant toxicity tests. (It can be noted that in all other respects AS 4736 is similar to EN 13432). 

Consequently, industrial compostability is based on AS 4736-2006 including an earthworm toxicity test (Section 5.5.2). In addition, the seedling logo is used under license of European Bioplastics. 

The eco-toxicity of composted Ecoflex was investigated in an earthworm acute toxicity test following the OECD guideline 207 (reference). In this test, earthworms... 

Such simple procedures, however, cost a lot of money. To obtain a single toxicity figure, for example, many tests need to be conducted to answer questions of interest such as Does this chemical cause cancer Does this chemical cause malformation and so forth. In fact, more than 20 animal toxicity tests are needed to answer such questions and obtain a toxicity figure. This could cost approximately USD 15 million. Similarly, to obtain a single exposure figure, the tests on residue analysis and environmental behaviour can cost up to USD 5 million. To examine the toxicity of natural organisms usually three aquatic species are tested as representatives of the water environment fish, water flea, and algae. For terrestrial species, earthworms, honey bees, and birds are tested. For these tests, approximately USD 1 million is needed. 

Earthworm, Acute Toxicity Tests (original guideline, adopted April 4, 1984)... 

ASTM. 1995. Standard guide for conducting a laboratory soil toxicity test with lumbricid earthworm Eisenia foetida. ASTM 1996 Annual Book of Standards Vol. 11.05, E1676-95. American Society for Testing and Materials, West Conshohocken, PA, pp. 1093-1109. 

Organization of Economic Cooperation and Development (OECD). 1984. Earthworm, acute toxicity tests, Test Guideline No. 207. Organization for Economic Development and Cooperation Guidelines for Testing of Chemicals, Paris. 

Among the many published studies that have used the earthworm reproduction test to measure chemical toxicity, only a few have assessed contaminated field soils. Two studies have been conducted along the contamination gradients from two smelting works (Spurgeon and Hopkin, 1995 Posthuma et al., 1998). Both studies found that earthworm reproduction was affected by elevated metal concentrations in soil close to the point source. Studies in contaminated soils have indicated that reproduction can be influenced also by the soil characteristics (Saterbak et al., 1999). This makes the choice of suitable control soils vital for the assessment. 

Van Gestel, C.A.M., Van Dis, W.A., Van Breemen, E.M. and Sparenburg, P.M. (1989) Development of a standardized reproduction toxicity test with the earthworm species Eisenia andrei using copper, pentachlorophenol and 2,4-dichloroaniline. Ecotoxicology and Environmental Safety, 18, 305-312. 

Invertebrate tests Earthworm - acute toxicity test... 

Kula, H. Larink, O. (1998) Tests on the Earthworms Eisenia fetida and Aporrectodea caliginosa, in Handbook of soil invertebrate toxicity tests, H. Lokke and C.A.M. van Gestel (eds), lohn Wiley Sons, Chichester, pp. 95—112. 

S. Verstichel- Organic Waste Systems (OWS) Final Report, Ecotoxicity Tests—Cress Test. Summer Barley Plant Growth Test Earthworm, Acute Toxicity Test Daphnia, Acute Toxicity on Compost Residuals of EPI-TDPA-Study CH-3/2 (Cress Test), Study CH-3/3 (Summer barley plant growth test) Study CH-3/4 (Earthworm, acute toxicity test). Study CH-3/5 (Daphnia, acute toxicity test)... 

EU criteria for the classification of substances hazardous to the non-aquatic environment are developing from terrestrial toxicity tests in higher plants and earthworms. The R-phrases R56 (toxic to soil organisms), R54 (toxic to flora) and R55 (toxic to fauna) have been established and test methods are under development. 

OECD (1984b) Guide-line for Testing of Chemicals Earthworm Acute Toxicity Test, OECD, Paris. 

In the acute toxicity test, earthworms are exposed to high concentrations of the test material for short periods of time. According to OECD guidehne 207 earthworms are exposed to soil and compost in varying amounts. Following 14 days of exposure, the number of surviving earthworms is counted and weighed and the per cent survival rates are calculated. The earthworms are exposed to several ratios of compost and soil mixtures. 

Simplified notifications, for substances produced or imported at less than one tonne per year. Minimal data are required. These data include melting point, water solubility, and octanol-water partition coefficient. For organic substances, the simplified notification must also include data from a test of ready biodegradability and, if the substance is not readily biodegraded, a test report on acute aquatic toxicity (ideally to fish). An earthworm acute toxicity test may be required. For inorganic substances, testing on acute aquatic toxicity (and, under certain circumstances, acute toxicity to earthworms) is required [145,146]. 

Toxicity testing of soil—where HCB is more likely to be found than in water—is less common. As described in Chapters 2 and 3, terrestrial toxicity testing is often not a part of formal risk characterization. Some scientists have tested the effect of exposure to HCB-contaminated soil on earthworms and found that HCB can bioaccumulate (see, e.g., [105]). 

Invertebrate acute and chronic toxicity tests are usually carried out on earthworms Eisenia spp. The acute test is run according to OECD 207 [60] that observes mortality and biomass fluctuations after 2 weeks of exposure. According to OECD 222 [61], the reproduction test examines the growth and mortality of adult worms after 4 weeks exposure, and the number of offspring present in soil after a further 4 weeks. 

OECD Guideline for the Testing of Chemicals 207 Earthworm Acute Toxicity Test, Organisation for Economic Co-operation and Development, Paris, France, 1984. 

The acute test does not seem to be suitable for the analysis of biodegradable materials, especially when the polymers are digestible by the earthworms. Compost is an optimal nutrition source for these animals and should never be tested to determine earthworm toxicity. The weight gain from the feed effect may cover possible smaller inhibition... 

The inhabitants of the soil include the nematodes (the most numerous multicellular animals on Earth), oligochaetes (earthworms), arthropods (crustacea, arachnids, insects), and gastropods (snails). The ecotoxicity tests which have been mostly used to test the effect of biodegradable polymers on solid substrates (such as compost and soil) are the Earthworm Acute Toxicity Test, ISO 11268-1 [76] and the Daphnia (a widespread crustacean) Acute Immobilisation and Reproduction Test [77]. 

OECD Test No.207, Earthworm, Acute Toxicity Test, 1984. 

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