Linz-Donawitz (LD) slag, containing 29% calcium (Ca), 21% iron (Fe), and 5% magnesium (Mg), is a by-product of the iron and steel-making industry. It is produced in large quantities in Europe and poses a substantial disposal problem. A field trial was conducted to study whether LD slag could be used as a dolomitic liming agent for pastures. The effects of six LD slag rates (0, 1000, 1500, 3000, 5000, and 7500 kg LD slag/ha), with or without NPK fertiliser, on soil properties, pasture yield, and botanical composition were investigated at two locations, Derio and Abadiano (Bizkaia, northern Spain). Soil at Derio was a fine silty, mixed (acid), mesic Typic Udorthent and at Abadiano a fine loamy, mixed (nonacid), mesic Aquic Udifluvent. At Derio, the 3-year trial was laid out on a newly established pasture of perennial ryegrass (Lolium perenne L.), cocksfoot (Dactylis glomerata L.), and white clover (Trifolium repens L.), whereas at Abadiano the trial was on a resident pasture dominated by yorkshire fog (Holcus lanatus L.) and browntop (Agrostis tenuis Sibth.). Application of LD slag increased the soil pH linearly at both sites. At A94050 Received 2 May 1994; accepted 15 November 1994Derio, the 7500 kg slag/ha rate increased the soil pH from 5.3 to 6.4, whereas at Abadiano the pH was raised from 5.7 to 6.5 and from 5.8 to 6.7 with and without NPK fertilisation respectively. The increase in pH was accompanied by a decrease to less than 5% in the percentage of Al saturation in the cation exchange complex. At Derio, soil exchangeable Ca increased in comparison with the control, by a factor of 1.8 and 2.3, with and without NPK fertilisation, respectively. At Derio, pasture yield increased with slag application, the second year responses being the largest (41% increase with 3000 kg slag/ha). At Abadiano, pasture yield did not respond to slag, but the botanical composition changed, with the contribution of browntop and yorkshire fog decreasing, and the contribution of red fescue (Festuca rubra L.) and ribwort (Plantago lanceolata L.) increasing. According to the results, LD slag appears to be a useful liming material for correcting soil acidity on pasture soils. As a consequence, the agronomic use of LD slags will contribute towards solving the environmental problem of their disposal.

Linz‐Donawitz (LD) slag, a by‐product of the iron and steelmaking industry (29% Ca, 5% Mg w/w) produced in large quantities in Europe, poses a substantial disposal challenge. A field assay was conducted to study whether LD slag could be used as a dolomitic liming agent for pastures. Six slag rates (0, 1000, 1500, 3000, 5000, and 7500 kg ha−1), with or without NPK fertilizer, were investigated for their effects on soil properties, mineral concentrations of forage, and forage yield at Bizkaia, Spain, on a Derio silty clay soil [fine silty, mixed (acid), mesic Typic Udorthent]. The 3‐yr study was done on a newly established pasture of perennial ryegrass (Lolium perenne L.), cocksfoot (Dactylis glomerata L.), and white clover (Trifolium repens L.). Slag application increased soil pH linearly, especially where fertilizer was not applied. The 7500 kg rate, without NPK fertilization, increased soil pH from 5.3 to 6.5. When 3000 kg ha−1 of slag was applied, the increase in soil pH was accompanied by a decrease of AI saturation percentage in the cation exchange complex, to <10%. At this rate, exchangeable Ca and Mg increased in comparison with the control, by a factor of 1.8 and 2.3, with and without fertilization, respectively. Slag application resulted in higher Ca, Mg, and P, lower K and Mn plant concentrations, and increased herbage yield. LD slag appears to be a useful liming material for correcting soil acidity on pasture soils and for increasing Ca, Mg, and P concentrations in plants.

The 'fitness for purpose' of a probabilistic model designed to assess dietary exposure to pesticides was validated. The model had to meet two prerequisites. First, it should provide more realistic estimates of intake than conservative methods. Second, it should not underestimate 'true' intakes. True intakes were estimated using a duplicate diet study. Three approaches were used to check the prerequisites: visual comparison, a statistical test of a high percentile, and a comparison for each infant of the duplicate diet, conservative and model intake values. Compliance with the prerequisites was met for the six pesticides selected, in the three approaches. Model outcome distributions reduced the uncertainty, considered as the difference between conservative and duplicate diet intakes, by 75-98% for high percentiles, depending on the pesticides. A sensitivity analysis of the model based on analysis of variance for selected factors was conducted for three pesticides. The factors included concentration and food consumption input data presentations, values assigned to pesticide-food commodities without analysis, values assigned to samples with results below the limit of reporting, unit-to-unit variability and processing factors. Their significance and relevance were studied. Assigning values to pesticide-food commodities without analysis and processing factors, when available, were the most relevant factors in this study.

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