Research & reports

James R. Preer, Ahmed N. Abdi, Harkewal S. Sekhon, George B. Murchison · Journal of Environmental Science and Health Part A Environmental Science and Engineering and Toxicology · Global

This study investigated cadmium (Cd) and zinc (Zn) concentrations in vegetables grown in community gardens on different urban soils. Vegetables from a low-pH urban soil without contamination history showed higher Cd and Zn levels than those from a reclaimed landfill with digested sewage sludge, and also higher than a low-metal, neutral-pH site. Liming on the low-pH site reduced Cd and Zn concentrations in beet, lettuce, radish, and Swiss chard leaves, reaching background levels after four years. The findings indicate that soil pH is more important than total soil Cd and Zn in determining vegetable metal availability.

M. Krelowska‐Kulas · Food / Nahrung · Poland (Kraków)

An investigation using atomic absorption spectroscopy in Kraków, Poland, found that vegetables from urban allotment gardens had average levels of lead, cadmium, copper, zinc, and iron several times higher than control samples from farms 100 km away. In some cases, maximum levels of certain elements approached the admissible limit. However, average levels of lead and cadmium in pigs and cattle showed no reason for objection.

P. van Lune · Netherlands Journal of Agricultural Science · Netherlands

A study analyzed cadmium (Cd) and lead (Pb) in soils and crops from 57 allotment gardens in potentially contaminated areas of the Netherlands. The median Cd and Pb concentrations in the soil samples were found to be higher than those in soils used for arable farming and horticulture. However, Cd and Pb concentrations in the crops themselves were normal.

Howard J. Atkinson, Naomi Gibson, Harry C. Evans · Plant Pathology · United Kingdom (Leeds)

A survey of 140 growers across 12 allotment sites around Leeds, UK, identified a wide range of crop pests, with brassicas, potatoes, and carrots being more frequently damaged. Soil samples from 33 plots at 10 established sites and 6 plots at 2 new sites revealed potentially damaging levels of pale potato cyst nematode in 21 and 1 plots, respectively. Widespread overwintering populations of carrot fly larvae and pupae were also found in soil samples from eight sites.

T. M. Spittler, William A. Feder · Communications in Soil Science and Plant Analysis · United States

This study demonstrated a serious problem of lead contamination in Boston's urban environment by analyzing about 900 soil samples from backyards, play areas, community gardens, and playgrounds using X-ray fluorescence spectroscopy. An average lead level of 800 ppm was found, traceable to the past widespread use of lead paint. Selected plant species grown in soils with lead levels ranging from 100–2000 ppm showed differing affinities for lead uptake, with fruits taking up less than roots and roots less than tops, indicating positive translocation of lead from soil into plant tissue.