Toxicity of the pesticide alpha-cypermethrin to four soil nontarget invertebrates and implications for risk assessment.

Alpha-cypermethrin, a synthetic pyrethroid, is used as an insecticide in agricultural settings and is increasingly replacing organophosphates and carbamates because of lower application rates and lower toxicity to mammals. Because very little is known about the acute and chronic toxicity of this compound for soil-living organisms, the present study investigated acute and sublethal toxicity of alpha-cypermethrin for four terrestrial invertebrate species in an agricultural soil from Norway. Bioassays with the earthworm Eisenia fetida, the potworm Enchytraeus crypticus, the springtail Folsomia candida, and the land snail Helix aspersa were performed according to slightly modified versions of Organization for Economic Cooperation and Development (Paris, France) or International Organization for Standardization (Geneva, Switzerland) guidelines and resulted in median lethal concentrations of greater than >1,000 to 31.

Recovery of cholinesterase activity in the earthworm Eisenia fetida Savigny following exposure to chlorpyrifos.

Organophosphorus (OP) insecticides inhibit cholinesterase activity, an essential process in the nervous system of most animals. Re-establishment of active enzymes is slow and depends on elimination of the insecticide from the body followed by two lengthy processes: Reactivation and/or biosynthesis of new enzymes. Earthworms (Eisenia fetida) were exposed to either clean or chlorpyrifos-containing (240 mg/kg) soil for 48 h.

Effects and uptake of polycyclic aromatic compounds in snails (Helix aspersa).

The International Standardization Organization recently launched a soil toxicity test with snails (Helix aspersa). We assessed the sensitivity of this test for seven polycyclic aromatic compounds. Control animals had 100% survival and low variability for growth measurements.

Functional and community-level soil microbial responses to zinc addition may depend on test system biocomplexity.

The effect of zinc on soil nitrification and composition of the microbial community in soil was investigated using a full factorial experiment with five zinc concentrations and four levels of biological complexity (microbes only, microbes and earthworms (Eisenia fetida), microbes and Italian ryegrass (Lolium multiflorum var. Macho), and microbes, ryegrass and earthworms). After 6 weeks of exposure, the activity of soil nitrifying bacteria was measured and the microbial community structure was characterized by phospholipid fatty acid (PLFA) analysis.

Benzo(a)pyrene shows low toxicity to three species of terrestrial plants, two soil invertebrates, and soil-nitrifying bacteria.

We examined the toxicity of benzo(a)pyrene (BaP) to several standard test organisms including the seed emergence and early life-stage growth of three terrestrial plants (Trifolium pratense, Lolium perenne, and Brassica alba), the survival and reproduction of enchytraeids (Enchytraeus crypticus), and the nitrifying ability of soil bacteria. To also have a look at possible food-chain effects, we included a two-species reproduction test with predatory mites (Hypoaspis aculeifer) and collembolan (Folsomia fimetaria) prey. No effect or only weak effects even at very high BaP concentrations were observed for all tests.

Toxicity of three halogenated flame retardants to nitrifying bacteria, red clover (Trifolium pratense), and a soil invertebrate (Enchytraeus crypticus).

Halogenated flame retardants have a high sorption affinity to particles, making soils and sediments important sinks. Here, three of the most commonly used flame retardants have been tested for sub-lethal toxicity towards soil nitrifying bacteria, a terrestrial plant (seed emergence and growth of the red clover, Trifolium pratense), and a soil invertebrate (survival and reproduction of Enchytraeus crypticus). Tetrabromobisphenol A (TBBPA) was quite toxic to enchytraeids, with significant effects on reproduction detected already at the 10 mgkg(-1) exposure level (EC(10)=2.

Polycyclic aromatic hydrocarbon ecotoxicity data for developing soil quality criteria.

With the overall perspective of calculating soil quality criteria (SQC) for the group of polycyclic aromatic hydrocarbons (PAHs), the existing ecotoxicity data for the soil compartment have been reviewed. The majority of data useful in the context of deriving SQC are of recent origin. Soil quality criteria are considered valuable tools for assessing the environmental risk of contamination, as they may give guidance on concentration limits for various chemicals to protect the function and structure of ecosystems.

Toxicity of eight polycyclic aromatic compounds to red clover (Trifolium pratense), ryegrass (Lolium perenne), and mustard (Sinapsis alba).

The effect of eight polycyclic aromatic compounds (PACs) on the seed emergence and early life-stage growth of three terrestrial plants (Sinapsis alba, Trifolium pratense and Lolium perenne) were studied in a greenhouse, using a Danish agricultural soil with an organic carbon content of 1.6%. After three weeks of exposure, seed emergence and seedling weight (fresh weight and dry weight) were determined.

Effects of the antibacterial agents tiamulin, olanquindox and metronidazole and the anthelmintic ivermectin on the soil invertebrate species Folsomia fimetaria (Collembola) and Enchytraeus crypticus (Enchytraeidae).

Veterinary pharmaceutical products such as antibacterial agents and antiparasitics are widely used to control diseases and promote production in the agricultural sector. Exposure of non-target organisms are a likely result of using manure from treated live stocks or from dung dropped on the field by grazing animals. The aim of this study was to determine the toxic threshold levels of three antibacterial agents (tiamulin, olanquindox and metronidazole) and one anthelmintic (ivermectin) to two species of soil dwelling organisms (springtails and enchytraeids), that are often found in bio-solids such as manure or dung.

Relative sensitivity of three terrestrial invertebrate tests to polycyclic aromatic compounds.

In a project investigating the ecotoxicity of polycyclic aromatic compounds (PACs), we have previously reported on the sublethal toxicity of eight PACs to springtails (Folsomia fimetaria) and enchytraeids (Enchytraeus crypticus). The model substances included four polycyclic aromatic hydrocarbons (PAHs) and four N-S-O-heterocyclics. Here, new data are presented on the effects of PACs on the survival and growth of the earthworm Eisenia veneta, showing that, in general, earthworm growth was reduced at PAC concentrations above 25 mg/kg soil dry weight.

Soil microbial toxicity of eight polycyclic aromatic compounds: effects on nitrification, the genetic diversity of bacteria, and the total number of protozoans.

Eight polycyclic aromatic compounds (PACs) were tested for their toxic effect on the soil nitrification process, bacterial genetic diversity, and the total number of protozoans (naked amoebae and heterotrophic flagellates). After four weeks of exposure in a well-characterized agricultural soil, toxic effects were evaluated by comparison to uncontaminated control soils. All PACs affected the nitrification process, and the calculated no-observed-effect concentrations (NOECs) for nitrification were 79 mg/kg for pyrene, 24 mg/kg for fluoranthene, 26 mg/kg for phenanthrene, 72 mg/kg for fluorene, 23 mg/kg for carbazole, 22 mg/kg for dibenzothiophene, 75 mg/kg for dibenzofuran, and 1,100 mg/kg for acridine.

Soil ecotoxicity of polycyclic aromatic hydrocarbons in relation to soil sorption, lipophilicity, and water solubility.

A data set was generated aiming to predict the toxicity of PAHs to soil organisms. Toxicity data include the effects of 16 PAHs on the survival and reproduction of the soil-dwelling springtail Folsomia fimetaria. The results show that only PAHs with reported log Kow values < or = 5.

Joint toxicity of linear alkylbenzene sulfonates and pyrene on Folsomia fimetaria.

Surfactants may enhance the biodegradation of hydrophobic substances in soils. This has partly been attributed to an increase in the bioavailability, brought about by the presence of surfactants. The aim of this study was to examine the ecotoxicological effects of the detergent linear alkylbenzene sulfonate (LAS) and the polycyclic aromatic hydrocarbon pyrene, alone and in combination, using the survival and reproduction of the collembolan Folsomia fimetaria as endpoints.

Studies on the effect of soil aging on the toxicity of pyrene and phenanthrene to a soil-dwelling springtail.

Soil samples spiked with five concentrations of pyrene and phenanthrene were aged for 0, 10, 40, and 120 d before toxicity was investigated using a standardized bioassay with the soil-dwelling collembolan Folsomia fimetaria L. Toxic effects were measured as reductions in survival and reproductive output after 3 weeks of exposure. Both pyrene and phenanthrene were degraded in the test system during storage, phenanthrene to a higher degree than pyrene.

Relative sensitivity of one freshwater and two marine acute toxicity tests as determined by testing 30 offshore E & P chemicals.

Acute toxicity of 30 offshore E & P (Exploration and Production) chemicals was measured using the three standard test organisms Daphnia magna (freshwater cladoceran), Acartia tonsa (marine copepod) and Skeletonema costatum (marine diatom alga). Test chemicals included 20 water-soluble and 10 (partially) non-soluble products. For 22 out of the 30 chemicals, the difference in sensitivity between the three tests varied within one order of magnitude.

Effects of eight polycyclic aromatic compounds on the survival and reproduction of Enchytraeus crypticus (Oligochaeta, Clitellata).

The effects of eight polycyclic aromatic compounds (PACs) on the survival and reproduction of the enchytraeid worm Enchytraeus crvpticus were investigated in an agricultural soil with an organic carbon content of 1.6%. With the exception of acridine, which showed a strong binding to the test soil and a subsequent low toxicity, polycyclic aromatic hydrocarbons and neutral N-, S-, O-monosubstituted analogues showed a similar toxicity to the enchytraeids.