White Sucker (Catostomus Commersoni) Growth and Sexual Maturation in Pulp Mill-Contaminated and Reference Rivers

Abstract

Induction of hepatic ethoxyresorufin-0-deethylase (EROD) activity and accumulation of chlorophenolic compounds typical of bleached-kraft mill effluent (BKME) in fish sampled downstream of a pulp mill on the St. Maurice River, Quebec, Canada, provided evidence of chemical exposure to BKME. In comparison, fish sampled over the same distances and in similar habitats in a noncontaminated reference river, the Gatineau River, demonstrated low EROD activity and contamination levels. Accelerated growth of white suckers occurred between 2 and 10 years of age in both rivers at downstream stations relative to upstream stations, suggesting the existence of gradients of nutrient enrichment independent of BKME contamination. The impact of BKME exposure was expressed as reduced investment in reproduction, as revealed by greater length at maturity, reduced gonad size, and more variable fecundity. These effects were not obvious in simple upstream-downstream comparisons, but became evident when fish from the uncontaminated Gatineau River showed increased gonadal development and reduced age and size at maturity in response to enhanced growth rates.Keywords-Bleached-kraft mill effluent EROD MFO 317

Evaluation of the Sub-lethal Toxicity of Bleached Kraft Pulp Mill Effluent to Carassius auratus and Dicentrarchus labrax

“…This was in agreement with other studies, reporting the role of a BKPME sample, resulting from the use of elemental chlorine in the bleaching process, in the inhibition of reproduction in fish and in GSI reduction Munkittrick et al 1994;Gagnon et al 1995;Denslow et al 2004). According to Sepúlveda et al (2004), other studies have reported that the decrease in gonad size may not always occur after exposures of fish to BKME (McMaster et al 1996a, b).…”

Lesions and parasites in white suckers, Catostomus commersoni, in bleached‐kraft pulp mill‐contaminated and reference rivers

“…The monthly averaged water flow, temperature, and p H for 1990 were 465 k 165 m3/s, 8.3 -1-7.5"C, and 6.7 f 0.3 [25]. At La Tuque, about 1 km upstream from a hydroelectric dam, the river receives the ef-fluent of a pulp mill producing cellate bleached kraft, semibleached-or fully bleached-kraft pulp from black spruce and jackpine [25]. Two bleaching lines are used with the following bleaching sequences: CdNEHD and CdEoDED (Cd, first bleaching stage where chlorine dioxide represents a minor part, N for neutralization, E for extraction with alkali, H for hypochlorite, D for chlorine dioxide, and Eo for caustic extraction with addition of elemental oxygen) [D. Adams, personal communication].…”

“…The drainage basin is about half the size of that of the St. Maurice (23,724 km'), and the flow rate is proportionally lower (295 m3/s, monthly average for 1990) making the two rivers hydrodynamically comparable. It is similar in latitude, water pH (6.5 k 0.1, monthly average for 1990), and temperature (8.8 k 8.7"C, monthly average for 1990) to the St. Maurice, and the drainage basin has similar land use (primarily forest) and geology [25]. Furthermore, it has log driving and hydroelectric dams, but no industrial effluent.…”

“…1). The monthly averaged water flow, temperature, and p H for 1990 were 465 k 165 m3/s, 8.3 -1-7.5"C, and 6.7 f 0.3 [25]. At La Tuque, about 1 km upstream from a hydroelectric dam, the river receives the ef-fluent of a pulp mill producing cellate bleached kraft, semibleached-or fully bleached-kraft pulp from black spruce and jackpine [25].…”

Assessment of the alterations of the aquatic environment downstream from a polluted tributary of the river Po (Italy)

“…In fact, this same increase was observed, for example, in fish (Catostomus commersoni) living downstream from a pulp and paper mill. These fishes also exhibited several metabolic alterations (including monooxygenase enzyme alterations), delayed age and increased size at maturity, smaller gonads and low fecundity (Hodson et al, 1992;Gagnon et al, 1995).…”