Although toothpastes are considered as topical cosmetics that are not normally ingested, it is evident that they may contribute to the introduction of heavy metals and xenobiotics through buccal and gastrointestinal absorption. The purpose of this study was to determine the potential presence of metals and polyphenols in conventional, children's and herbal toothpastes. Metal analysis was conducted by using the Microwave Plasma-Atomic Emission Spectrometer and the total polyphenolic content was determined by using the Folin-Ciocalteu test. Results showed that cadmium and mercury were absent in all toothpastes while zinc and tin exhibited high values. This was because the latter two metals are incorporated as part of the ingredients. In the case of polyphenols, the highest value was obtained in one of the samples from the children's toothpaste category while the lowest value was obtained from the conventional toothpaste category. Lead and nickel were two other metals that fell outside the limits for EU and US standards. Most of these limits are usually applicable to topical cosmetic products or food products. However, these may not adequately cover oral hygiene products, such as toothpastes.

This study investigated the effect that poultry, cattle, swine manures, and artificial fertilizer have on the yield and quality of lettuce (Lactucasativa L.). The ground water contamination potential of these fertilizers when applied to calcareous soil was also studied. Lettuce plants were cultivated in pots containing soil amended with either of the fertilizers together with a no-fertilizer control. The amount of fertilizer applied to soil was in line with that used by the lettuce growers in Malta. The experiment, including 20 replicates for each treatment, was set up in a greenhouse and the crop height, width, fresh and dry mass, root length, sap NO3 - and K + , and heavy metal content were monitored. The drain water from the pots was analysed periodically for NO3 - content and salinity. The best crop performance was obtained from poultry manure followed by swine manure, cattle manure and artificial fertilizer. Yield from the control soil was poor and also resulted in a crop containing the highest NO3 - concentration in the sap. No significant difference was found in sap NO3 - concentration in plants grown in soil amended with the fertilizers. The heavy metal content concentration in the plants was not significantly different except for Ni, Mn and Cu. The highest NO3 - leaching was shown in the soil amended with manure, especially with that from poultry. Crops grown on cattle manure showed the highest variation in crop mass and also the lowest yield-to-ground water NO3 - contamination potential ratio.