Maturity and hygiene quality of composts and hygiene indicators in agricultural soil fertilised with municipal waste or manure compost

Composts produced from municipal source separated biowaste (Biowaste), a mixture of biowaste and anaerobically digested sewage sludge (Biosludge) and cattle manure (Manure) were examined for their maturity and hygiene quality. The composts were applied to a potato crop in 2004 and to a barley nurse crop of forage ley in 2005 in a field experiment. Numbers of faecal coliforms, enterococci, clostridia and Salmonella in field soil were determined 2 weeks and 16 weeks after compost applications. Municipal compost batches chosen based on successful processing showed variable maturity during field application, and the need to evaluate compost maturity with multiple variables was confirmed. The numbers of faecal coliform were similar in all compost types, averaging 4.7 and 2.3 log 10 CFU g-1 in the first and second years, respectively. The highest number of enterococci was 5.2 log10 CFU g-1, found in Manure compost in the first year, while the highest clostridia numbers were found in Biosludge compost, averaging...