Trace elements in major solid-pesticides used in the Gaza Strip.

This study describes the purity of pesticides used in Gaza in terms of trace elements. A semi-quantitative EMMA-XRF technique and quantitative ICP/OES was used to determine the concentrations of Al, As, Ba, Br, Ca, Cd, Co, Cr, Cu, Fe, K, Mn, Ni, Pb, Rb, Sc, Se, Sr, Ti and Zn in 50 of the most commonly used solid pesticides collected from the five central shops in the Gaza Strip. The results revealed that the pesticides contain considerable amounts of trace elements and do not comply with the expected-theoretical structure of each species. Moreover, they do not reflect the actual constituents mentioned in the trade labels. Interviews with market owners and field surveys confirmed that the pesticides were not pure. In some cases they have been mixed in local markets with minor inorganic species without a scientific basis. They may also have been smuggled into Gaza with differing impurities. The results indicate that pesticides should be considered as a source of certain trace metals (particularly Cu, Mn and Zn) and other elements (Br, Sr and Ti), which may affect their mass balances in soil and groundwater as well as their plant uptake. Different scenarios and calculation models of the transport of trace elements in soil and groundwater of the Gaza Strip should include pesticides as an additional source.