Bioavailability and influence of ¹⁴C-carbofuran on Eisenia andrei avoidance, growth and reproduction in treated natural tropical soils.

The bioavailability of carbofuran to the compost worms Eisenia andrei and the influence of its residual amounts on the avoidance, reproduction and growth of this species were studied in two natural tropical soils: a Typic Humaquept (GM) and a Typic Hapludox (LVD), as indicated by the Brazilian environmental authorities for ecotoxicological tests. The worms avoided the soil LVD treated with different doses of carbofuran. The pesticide also affected the production of juvenile specimens in both soils, but cocoon production was reduced only in the GM soil.

Comparative assessment of the effect of synthetic and natural fungicides on soil respiration.

As toxic pesticide residues may persist in agricultural soils and cause environmental pollution, research on natural fungicides to replace the synthetic compounds is currently increasing. The effect of the synthetic fungicide chlorothalonil and a natural potential fungicide on the soil microbial activity was evaluated here by the substrate-induced respiration by addition of glucose (SIR), as bioindicator in two soils (Eutrophic Humic Gley-GHE and Typic Eutroferric Chernosol-AVEC). The induced soil respiration parameter was followed during 28 days after soil treatment either with chlorathalonil (11 μg·g(-1)), or the methanolic fraction from Polymnia sonchifolia extraction (300 μg·g(-1)), and (14)C-glucose (4.

Earthworm (Eisenia andrei) avoidance of soils treated with cypermethrin.

The pyrethroid insecticide cypermethrin is used for agricultural and public health campaigns. Its residues may contaminate soils and the beneficial soil organisms, like the earthworms, that may ingest the contaminated soil particles. Due to its ecological relevance, earthworms Eisenia andrei/fetida have been used in different ecotoxicological tests.

Influence of substrate on bioaccumulation of 14C-paraquat in compost worms Eisenia foetida.

Contamination of soil with pesticides can be evaluated using toxicity tests with worms because their ecological niche makes them good bioindicators. Bioaccumulation in compost worms of [methyl-14C] paraquat (1,1'-dimethyl-4,4'-bipyridinium dichloride) was measured after three-month exposure in two substrates with differing physicochemical characteristics, in particular their organic matter and clay contents. The treatments were 1.

Influence of soil properties on bioaccumulation of 14C-simazine in earthworms Eisenia foetida.

The toxicity of pesticides has been evaluated by several methods including tests with earthworms in both artificial and natural soils treated with the compounds. The ecological niches of earthworms make them good bioindicators of soil contamination. The bioaccumulation of 14C-simazine (6-chloro-N2-N4-diethyl- 1,3,5-triazine-2,4-diamine) was evaluated in earthworms (Eisenia foetida) maintained during three months in two substrates with different physical-chemical characteristics.