Effects of the insecticide endosulfan on nitrification in low pH agricultural soils

Abstract

Two methods of measuring nitrification in soil bioassays were compared for their sensitivity in estimating toxic effects of endosulfan, a cyclodiene insecticide. Both technical grade endosulfan (95% pure) and endosulfan formulated as a commercial preparation (Thiodan 4EC) were tested in a sandy loam (pH 5.7), a silt loam (pH 5.0), and a clay loam (pH 4.9) soil. Nitrification was assayed using both soil perfusion and batch incubation techniques. There was a significant difference in the nitrification pattern evidenced by the three soils.In the sandy loam soil up to 90% of the added ammonium ion was converted into nitrate within 30 days, while the silt loam required 40 days to achieve similar nitrate levels.

Glyphosate effects on microbial biomass in a coniferous forest soil

“…However, this cannot be verified. Formulated products often have more pronounced effects on nontarget systems than do the technical grade pesticides they contain (Reddy et al, 1984;Stratton 1990a). Often this is due to interactions between the various components of these mixtures (Stratton, 1990a).…”

“…Formulated products often have more pronounced effects on nontarget systems than do the technical grade pesticides they contain (Reddy et al, 1984;Stratton 1990a). Often this is due to interactions between the various components of these mixtures (Stratton, 1990a). However, the effects of pesticides in their formulated state is the information required for an accurate assessment of environmental impact.…”