Lead, cadmium, zinc, copper and nickel distributions in vegetables and soils of an intensely cultivated area and levels of copper, lead and zinc in the growers

Abstract

A study has been made of an intensively cultivated horticultural area, in production for less than 40 years since the drainage of the marsh from which it was formed. The muck soil varies in depth from 6 to 30 feet. Heavy applications of fertilizer and pesticides maintain high productivity. Crops include onions, carrots, potatoes, lettuce, celery, cabbage, cauliflower, parsnip and beet. Distribution of the trace heavy metals lead, cadmium, nickel, copper and zinc in the soils, crops and people was studied. The effect of cultivation practices on metal accumulation was determined by comparisons with undrained parts of the marsh. Marked soil profile effects were seen for all metals, especially for Cu. Crop levels revealed that Cu was relatively tightly held in the organic soil compared with the other metals, the order being Cu, Ni, Pb, Zn and Cd. Cadmium and Pb occurred at highest levels in the foliage of salad and leaf crops. Blood metal levels and concentrations in hair of the growers and the workers in packing stations were compared. Significant differenecs occurred for both Pb and Cu. Differences also occurred between males, females and in different age groups. 10 references, 5 figures, 12 tables.