The food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) were analyzed using carbon and nitrogen stable isotope ratios in Lake Katanuma. Lake Katanuma is a volcanic and strongly acidic lake (average pH 2.2) . In Lake Katanuma, potential sources of diets for the chironomid larvae are limited including a benthic diatom (Pinnularia braunii), a phytoplankton (Chlamydomonas acidophila), sulfate oxidizing bacteria, and vascular plants supplied from vegetation surrounding the lake. Based on the average carbon and nitrogen isotope ratios among these potential sources and sediment, benthic diatoms were considered to be most probable food source of the chironomid larvae. δ13C values of the chironomid were significantly different among seasons and habitat depths, suggesting that diet of C. acerbiphilus changed seasonally and with habitat depth.
The excretion, distribution and metabolism of3H-phencyclidine (PCP) were studied in male rats following oral administration. The radioactivity was mainly excreted in urine and to a lesser extent in feces. Most of the urinary radioactivity was excreted in the form of glucuronide conjugates of hydroxylated PCP metabolites and urinary excretion of unchanged PCP was minimal. Distribution study showed no marked amity for any particular tissue, although the levels in liver and prostate were a little high within 24 h after dosing. PCP was detected in brain by GC-MS.