Various factors influencing the quality of UVVIS spectra obtained for sea water (in 100 mm cells) have been tested. The spectrophometer instability and baseline drift introduced absorbance error of ~ 0.0002 and ~ 0.001, respectively. Deviations caused by improper blanks reached 0.005 ab-sorbance units. Standard deviation of absorbance values determined for samples collected in the Gulf of Gdansk during repetitive casts (0.008-0.022) significantly exceeded the detection limit based on variability of the blank sample (0.002).
W. Grzybowski, Institute of Oceanography, University of Gdansk, al. Marszalka Pilsudskiego 46, 81-378 Gdynia, Poland, e-mail: grzyb@panda.bg.univ.gda.pl