Aluminum Bioaccumulation in the Earthworm and Acute Toxicity to the Earthworm

Aluminum is a highly cytotoxic metal to plants, but its toxicity and accumulation to invertebrates in neutral soils is still unknown. This study is to determine the acute toxicity and bioaccumulation of aluminum to the earthworm. The ecotoxicity tests were based on the methods of international standardization of organization (ISO) and OECD guideline with some modification. The contents of aluminum were measured with Graphite Furnace Atomic Absorption Spectrometry. The experimental period of accumulation test was 32 days. The experiments indicated that aluminum had strongly toxic to earthworms with LC₅₀ of 532.33 mg Al/kg dry soil at pH of 7.0. There were about 1.7 mg monomeric Al/kg dry soil and 2.5 mg water-soluble Al/kg dry soil. Earthworms had ability to enrich aluminum at the low contaminated soils doses and bioaccumulation attained maximum then biodegraded obviously. There was a negative correlation evidently between the bioconcentration factor and the dose contaminated soils by Al.