The goal of this study is to determine whether or not there is an appreciable difference between concentrations of various metal ions present in conventionally grown and processed and organically grown and processed baby foods. Two prominent, commercially available brands were chosen to undergo comparative studies between both their own conventional and organic varieties of second stage green beans and carrots. Samples were tested for cadmium, calcium, iron, lead, nickel, and zinc. Two containers of each variety of baby food were sampled in triplicate, with purchases of foods being made in separate areas to ensure that each set came from different batches. Samples were digested with nitric acid, appropriately diluted, and analyzed for metal content by flame atomic absorption spectroscopy with the regular standard calibration curve and standard addition method. There was little overall difference in metal content between the conventional and organic foods tested.

The concentrations of heavy metals (Cd, Cu, Fe, Ni, Pb, Zn) were measured in water, and fish samples caught from the pond at Fishery Park in Unicoi County, TN. The water samples were collected once a week for 8 weeks. The amounts of metals in the muscle tissues, gill, and liver of the two fish species were measured. This was to determine if any correlation exists between the metal contents in water and those in the fish samples. The concentration ranges for the heavy metals found in the water samples are as follows: Zn 0.04-0.13; Cu, 0.00-0.00; Pb, 0.00-0.59; Cd, 0.0067-0.0071; Fe, 0.208-0.512; and Ni, 0.044-0.270 ppm. The concentration range for the heavy metals found in the fish tissues are as follows: Zn 0.0-0.48; Cu, 0.00-0.00; Pb, 0.00-0.43; Cd, 0.00-99.7; Fe, 25.7-1245.5; and Ni, 0.00-268.5 ppm. There was a strong correlation found between the water and fish tissue samples.

This study aims to determine the distribution of particulates carrying heavy metals at selected sites on a college campus using dandelion leaves as collectors. As a comparison, sites far away from the campus surrounding Bristol Motor Speedway Car Racing Stadium were also monitored. To reduce the probability of memory effects from the long-term atmospheric deposition or absorption of metals from soil a seasonal plant, dandelion, was used to monitor the metal contents. The metals monitored are cadmium, calcium, copper, chromium, iron, lead, and zinc. Fourteen sites were monitored and samples were collected once a week initially (growing time of the plant), and later at 4-week interval from 28th March to 31st August of 2007. The metal contents of the nitric acid digested and appropriately diluted samples were determined by flame atomic absorption spectrometry using the regular standard calibration curve and also the standard addition method. From the results obtained, and the careful log of the weather and human activities at the different sites, it is concluded that human activities played a major role in the distribution of metal-laden particulates. Also dandelion leaves were proven to be viable collectors of these particulates without memory effects and as indicators of current particulates generated rather than a long-term cumulative one.

Commercially available organic and conventionally grown vegetables were studied by quantitative determination of selected metals in them and to determine if any differences found are statistically significant. These findings can help the consumers to determine if the vegetable products are within the recommended maximum limits as proposed by the joint FAO/WHO Expert committee on organic foods designation. Eight edible vegetables were purchased from local stores in both the organic and conventionally grown categories. Samples were digested with concentrated nitric acid and the metals monitored were zinc, copper, lead, iron, cadmium, and nickel using flame atomic absorption. The concentration range for the heavy metals found are as follows: Zn, 2.04-69.4; Cu, 0.35-15.1; Pb, 0.00-3.99; Cd, 0.00-0.74; Fe, 2.52-319; and Ni, 39.9-53.8 μg/g. It was found that in general, conventional vegetables contain higher amounts of most of the heavy metals studied as compared to their organic counterparts. The study also showed that all vegetables products contain below the permissible limits for Zn, Cu, Ni, and Fe. For Pb all vegetables exceeded the safe limit except organic cucumber and conventional cabbage. For Cd, organic lettuce and green pepper, and conventional leafy green, green pepper, and spinach all exceeded the limit recommended by FAO/WHO.