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To investigate uptake of organic contaminants from sewage sludge (follow on SP0113) - SP0103

SP0103. Organic contaminants from sewage sludge.

Concern exists that organic contaminants from sewage sludge and sludge-treated soils may transfer into crops and livestock. There is a need to assess the pathways of transfer of organic pollutants in order to determine risks involved; this will aid decisions on which compounds should be regulated and the establishment of acceptable limits for the content and loading of these contaminants in sludge applied to agricultural land. In this study, long term experiments will be conducted to measure the residence time of the most persistent organic compounds in soil. Inputs to experimental plots will be assessed by measuring the amounts in added sewage sludge and measuring temporal changes in untreated control plots (to provide a measure of atmospheric inputs). The movement of organic contaminants from sludge to soil in treated plots will be evaluated. Effects of recent additions of contaminated sludge on microbial activity in soil will also be studied. Data from these studies will be used to enhance understanding of the risks of organic contaminants in soil-plant systems and the contribution of sludge-derived organic compounds to human and animal exposure.
To use long-term experimental plots to measure the residence time of the most persistent organic compounds in soil. The inputs to these plots will also be assessed by a) measuring the amounts in the sewage sludge's added in the experiments and b) measuring the changes with time in control (untreated) plots, which give a measure of atmospheric inputs. To evaluate the movement of organic compounds into crops from sludged plots. To construct mass balances for these compounds. To measure the effects of recent additions of contaminated sludge on the mircrobial activity in soil. Use the information collected to assess the risks posed by organic compounds from sewage applications to soil.
Project Documents
• Other : Published papers relating to SP0103   (14k)
Time-Scale and Cost
From: 1990

To: 1995

Cost: £126,000
Contractor / Funded Organisations
Rothamsted Research (BBSRC)
Fields of Study
Soil Protection