[1] Univ Northampton, SITA Ctr Sustainable Wastes Management, Northampton NN2 7AL, England
[2] Univ Leeds, Sch Earth & Environm, Sustainabil Inst, Leeds LS2 9JT, W Yorkshire, England
[3] St Lawrences Hosp Bodmin, Util Dept, Natl Hlth Serv Cornwall, Bodmin PL31 2QT, Cornwall, England
[4] Royal Cornwall Hosp, Util Dept, Natl Hlth Serv Cornwall, Truro TR1 3LJ, Cornwall, England
[5] Univ Exeter, Sch Geog Archaeol & Earth Resources, Camborne Sch Mines, Penryn TR10 9EZ, Cornwall, England