The formation of volatile N-nitrosamines in grass and maize silages.

Normal grass or maize silage generally had N-nitrosamines 1 mu g/kg. Only in special conditions did maize silage have about 5 mu g/kg. (Abstract retrieved from CAB Abstracts by CABI’s permission

The analysis of volatile N-nitrosamines in the rumen fluid of cows.

For 1 week 2 nonlactating Friesian cows were given hay with potassium nitrate 80 mg/kg bodyweight daily. Then nitrate 120 mg/kg was given into the rumen and rumen fluid was sampled every 15 min for the next 165 min. Greatest concentrations of nitrate, 3.9 and 2.9 mmol/litre in each cow, were present after 90 to 105 min. Dimethylnitrosamine was the only volatile N-nitrosamine found. (Abstract retrieved from CAB Abstracts by CABI’s permission

Effect of soil pH and ammonium and nitrate treatments on heavy metals in ryegrass from sludge-amended soil.

Perennial ryegrass was grown in pots on sludge-amended soil adjusted to 8 pH levels ranging from pH 4 to pH 7 and supplied with either ammonium sulphate or calcium nitrate. The chemical form in which N was applied influenced grass accumulations of Mn, Ni, Zn and Cd only when the difference in soil pH between the treatments, resulting from soil and plant factors, had developed to a sufficient extent to affect the availability of the contaminating metals for uptake by grass. (Abstract retrieved from CAB Abstracts by CABI’s permission

Effects of applications of sewage sludge and fertilizer nitrogen on cadmium and lead contents of grass.

During 5 successive years, 0, 6, 12 or 18 t/ha yr metal-bearing sewage sludge on a DM basis was applied to permanent grassland. Each sludge application was combined with various N treatments. Cd content of the grass increased considerably with increasing amounts of sewage sludge and fertilizer N; Cd content was higher in young than in old grass. The latter also applied to Pb but the increase in Pb content was less and the relation between the supply of Pb and the Pb content of the grass was poor. During the late autumn and winter the increase in Pb content was striking and was probably caused by pollution from the atmosphere. (Abstract retrieved from CAB Abstracts by CABI’s permission

Accumulation of heavy metals in the soil due to annual dressings with sewage sludge.

In a long term field experiment 0, 6, 12 or 18 tonnes/ha/yr of sewage sludge (dry matter basis) were applied to permanent grassland. Sludge application markedly increased the contents of Cd, Pb, Zn, Cu, Ni, Cr, Mo, to a depth of 15-25 cm, but Co, Mn and Fe contents were increased only in the surface 5 cm of soil. (Abstract retrieved from CAB Abstracts by CABI’s permission