Benzo(a)pyrene adsorbed to suspended solids in fresh water

The solubility of benzo(a)pyrene (BaP) in water is small, and measured total BaP concentration (t‐BaP) in fresh water is the sum of BaP dissolved in water (d‐BaP) and BaP adsorbed to suspended solids (p‐BaP). We have collected fresh water samples in a lake and rivers in Okayama Prefecture, Japan, and measured both d‐BaP and p‐BaP in each sample. The blue rayon method or solid–liquid extraction was used for extraction of BaP in water or in suspended solids, respectively. The measurement of BaP was done using high‐performance liquid chromatography according to our previously reported method. The present data indicate that p‐BaP was about 1.5 to 5 times higher than d‐BaP. In general, the amount of suspended solids in each sample did not show a correlation to p‐BaP. These results suggest that BaP adsorbed to suspended solids must be taken into account when assessment of t‐BaP is done in any given fresh water sample. © 2000 John Wiley & Sons, Inc. Environ Toxicol 15: 500–503, 2000