The use of biological indicators in studies of aquatic pollution (in fresh, estuarine or sea waters), as well as research about the metal transfers in food chains, need a great accuracy of the trace element determination. Therefore, as shown by the results of international intercalibration exercises, the mastery of analytical techniques is far from being perfect in all the laboratories. One of the main sources of error in atomic absorption results from non-specific absorptions due to the presence of important organic and mineral matrixes in biological materials and especially in aquatic and marine organisms. In this case, the correction of unspecific absorption by using deuterium lamp was insufficient and the determination of trace elements had to be preceded by a pre-instrumental stage which allowed the elimination of the organic matter by mineralization and of a large part of the mineral matrix by extraction. The previous separation was long and induced contamination risks. The use of the Zeeman effect background correction allows the transfer of most processes from the pre-instrumental to the instrumental stage. Moreover, the Zeeman effect has three advantages: (1) the background correction is effective up to 2 units of absorbance; (2) the correction is effective from 190 to 900 nm; (3) the method of the double beam is optimalized. The aim of this study was to apply the Zeeman effect to the determination of eight trace elements (Ag, Cd, Cr, Cu, Mn, Ni, Pb, Se) in three different biological solid samples, two originated from the marine environment (lobster hepatopancreas TORT-1, standard reference material from the National Research Council Canada; oyster tissues SRM 1566 from the US National Bureau of Standards) and one from the vegetable kingdom (tomato leaves, SRM 1573 from the US NBS). The experimental procedure is reduced to a minimum since it consists in the digestion of an aliquot of 100 mg of the powdered sample with 1 ml of concentrated nitric acid at 95°C for 1 h. Then the volume is adjusted to 4 ml with deionized water. The metal analysis is carried out using a graphite furnace coated with tantalum carbide. This analysis is achieved according to the method of standard addition. The three added concentrations used for each element are listed in Table 1. The analytical conditions and graphite atomizer program are indicated in Table 2. The temperature program has to be modified according to the type of equipment. The internal quality control of the suggested method related to four criteria: sensitivity, repeatability, accuracy, practicability. The results are shown in Table 3. The threshold of sensitivity (3 times the SD of a series of eight results obtained for a blank of digestion) are low: < 1 μg kg −1 for Ag, Cd and Mn; ∼ 1 μg kg −1 for Cr and Pb; 5 μg kg −1 for Cu and Ni and 15 μg kg −1 for Se. The variation coefficients, calculated for both two series of six determinations each, are generally included between 5 and 10%. The trace element concentrations determined by using this method are in perfect agreement with the certified values of the US NBS and NRC Canada (Table 3.) The quality of the results establishes the possibility of using a very easy and fast method to determine the level of eight trace elements in materials with high mineral and organic matter content.