Table 2.
Lead concentrations in soil, vegetables and fruits in UK national surveys of agricultural soils and commercial foodstuffs, and in urban gardens and allotments, including two case study sites with high concentrations of lead in the soil.
| Sampled area | Locations (UK) | Soil lead mg kg-1 dwt | Vegetable lead mg kg-1 fwt | References | |||||
|---|---|---|---|---|---|---|---|---|---|
| Area | Mean/median | Range | n | Vegetable/fruit | Mean | Range | n | Soils/vegetables | |
| Agricultural soils | England & Wales Soil (5 km grid), Food from UK shops. |
74 (Med) | NR | 5692 | Root vegetables Greens Potatoes Others |
0.05 (M) 0.004 (M) 0.003 (M) 0.013 (M) |
<0.05-0.28 NR NR NR |
120 24 24 24 |
[2,20] [9] [9] [9] |
| Urban garden soils | 50 cities, towns or villages. | 266 (GM) | 13-14100 | 4127 | NR | NR | NR | NR | [2] |
| Urban allotment and vegetable plot soils | 9 cities and towns. | 217 (GM) | 27-1676 | 94 | Lettuce Spinach Cabbage Broccoli Carrot Parsnip |
0.05 (GM) 0.14 (GM) 0.20 (GM) 0.21 (GM) 0.10 (GM) 0.13 (GM) |
<0.02-0.31 <0.02-1.69 0.06-1.54 0.06-1.01 0.02-0.33 <0.02-0.62 |
78 80 82 82 78 84 |
[19,19] |
| Urban allotment soils | 6 cities | 464 (M) | NR | 52 | Brassicas Legumes Potatoes Onions Soft Fruits All fruit and veg |
0.008 (M) 0.009 (M) 0.009 (M) 0.007 (M) 0.017 (M) 0.010 (M) |
NR NR NR NR NR <0.005-0.07 |
68 37 72 37 36 251 |
[21,21] |
| Contaminated allotment soils (Case study 1) | Newcastle Walker Rd |
1200 (M) | 490-1900 | 25 | Swede, turnip, beetroot, potatoes | <0.026 (M) | <0.001-0.13 | 11 | [1,1] |
| Contaminated allotment soils (Case study 2) | London, location undisclosed | 1050 (GM) | 513-2910 | 11 | Cabbage Carrots, parsnip, beetroot, potatoes |
1.83 (M) 2.82 (M) |
0.18-3.58 0.87-5.35 |
4 5 |
[3,3] |
GM= geometric mean, M= arithmetic mean, Med= median, n = the number of samples, NR = not reported, fwt = fresh weight. Figures in bold for vegetables indicate values in excess of current statutory limits [21] in commercially-produced food (0.1 mg kg-1 fwt in potatoes and onions,0.2 mg kg-1 fwt in small fruits and berries, 0.3 mg kg-1 fwt in brassicas).