PM19 Field-Based Effects Measures
Exhibit Hall
8:00 AM - Monday
(PM293) Physiological effects on carp in a river receiving the pulp and paper mill effluents, Japan.
Kishi, K.1, Onikura, N.1, Watanabe, A.1, 1 Japan Pulp & Paper Research Institute, Inc., Tsukuba, Ibaraki, Japan
ABSTRACT- In the past several years, we have investigated the environmental impact of pulp and paper mill effluents using a battery of bioassays combined with chemical analyses. Numerous studies have pointed out that physiological status of aquatic organisms is altered due to the exposure to pulp and paper mill effluents. The objective of present study was to evaluate physiological effects on fish in a river in Japan receiving the pulp and paper mill effluents. Studies were conducted through in 2001 to 2003. Carp were captured at several locations in a river, contaminated mainly by a pulp and paper mill and sewage plants. Liver, kidney, gill and plasma samples were then collected. 7-Ethoxyresorufin O-deethylase (EROD), glutathione-S-transferase (GST), glutathione peroxidase (GP), glutathione reductase (GR) and lipid peroxidation (LOOH) in homogenized tissues were measured as indicators of oxidative stress. Sex steroids, vitellogenins (Vit) and 8-hydroxydeoxyguanosine (8-OHdG) in plasma samples were also analyzed. Neither EROD nor Vit was induced at contaminated site throughout the studies. GST, GP, GR, LOOH, LOOH in tissues and 8-OHdG in plasma were significantly higher at the site contaminated by the effluents compared with those at the reference sites in 2001 and 2002. In addition, sex steroid levels in male carp, not female, were significantly lower at the contaminated area in 2001 and 2002 although gonad somatic index (GSI) values were not significantly different between the sampling points. These results suggested that fish at the polluted area were clearly under oxidative stress whereas the area was not in estrogenic environment. In 2003, however, these effects were not observed in carp captured at the contaminated site, suggesting the environment at the discharged site was improved. Results will be discussed in relation to the process change in the mill and the construction at the polluted area.
Key words: pulp and paper mill effluent, carp, oxidative stress, field study