Lead and cadmium in urban allotment and garden soils and vegetables in the United Kingdom

Abstract

In order to assess the intake of lead and cadmium by consumers of home grown vegetables in urban areas, replicated experimental plots of uniform size, comprising summer and winter crops, were established in 94 gardens and allotments in nine towns and cities in England.The geometric mean lead and cadmium concentrations for the soils (n = 94) were 217 μg g(-1) (ranging from 27 to 1,676 μg g(-1)) and 0.53 μg g(-1) (<0.2-5.9 μg g(-1)), respectively. Compared with agricultural soils, the garden and allotment soils contained elevated levels of lead but not cadmium.Lead concentrations in the vegetables ranged from <0.25 μg g(-1) to 16.7 μg g(-1) dry weight and cadmium concentrations ranged from <0.025 μg g(-1) to 10.4 μg g(-1) dry weight. Lead concentrations were higher than reported "background" levels, although <1% exceeded the statutory limit for saleable food in the UK (1 μg g(-1) fresh weight). Cadmium concentrations were generally similar to "background" levels.