Earthworm acute toxicity test

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

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

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. 

Invertebrate tests Earthworm - acute toxicity test... 

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)... 

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

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]. 

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

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. 

OECD (1984) OECD-guideline for testing of chemicals no. 207. Limit test. Earthworm Acute Toxicity Test, Paris, France. 

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. 

Palmer, S.and J. Beavers. 1997. Cry9C Protein in Plant Powder An Acute Toxicity Test with the Earthworm in an Artificial Soil Substrate (Final Report) Lab Project Number 452-103 452/102496/EWSDT.WCA/SUB452. Unpublished study prepared by Wildlife International Ltd. 39 p... 

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. 

According to OECD Method 207 [40] bioassays with earthworms could be applied as acute or chronic tests. In both cases 10 or more animals of known weight are exposed to 500 g of sample. For acute toxicity, the test duration is limited to 2 weeks and the number of survivors and their weight are determined and compared with the results obtained from reference samples. For the chronic test, the animals are left in the vessels for up to 2 months (and are fed, of course), in addition to the number of adult survivors the number of cocoons (reproduction) is evaluated. 

Dichlozoline (35), 3-(3,5-dichlorophenyl)-5,5-dimethyl-l, 3-oxazolidine-2,4-dione, is a white, crystalline compound, stable to heat and almost insoluble in water (2.5 mg/kg at 25°C). Its acute oral LD50 for rats is higher than 10 000 mg/kg. In 90-day feeding tests a daily diet of 70 mg/kg produced no pathological changes in mice and rats (Iwami et al., 1969 and 1974). The active substance is rapidly metabolised in rats and excreted. The metabolites are hydroxylated at position 4 of the benzene ring, and the oxazoline can also be modified (Sumida et al., 1973). Dichlozoline is not toxic to fish, bees or earthworms. 

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... 

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