Survival and iono-regulatory performance in Atlantic salmon smolts is not affected by atrazine exposure

Effects of atrazine on endocrinology and physiology in juvenile barramundi, Lates calcarifer (Bloch)

“…In fish specifically, aqueous exposure to environmentally relevant atrazine concentrations does not affect circulating or wholebody concentrations of vtg [2]. changes in plasma ion levels) were recorded in Atlantic salmon smolt (Salmo salar) after atrazine exposure at 6.5 mg/L to 22.7 mg/L for 7 d [36] and 100 mg/L for 21 d [37], but not at 1 mg/L to 100 mg/L for 4 d [38]. Our results that hepatic messenger RNA expression of vtg in juvenile barramundi is not affected by aqueous exposure to environmentally relevant atrazine concentrations (0.1-100 mg/L) thus support the conclusion that atrazine does not affect estrogenreceptor-mediated vtg expression.…”

“…Osmoregulatory disturbances (i.e. changes in plasma ion levels) were recorded in Atlantic salmon smolt (Salmo salar) after atrazine exposure at 6.5 mg/L to 22.7 mg/L for 7 d [36] and 100 mg/L for 21 d [37], but not at 1 mg/L to 100 mg/L for 4 d [38]. In a neotropical fish (Prochilodus lineatus), exposure to 25 mg/L atrazine for 14 d also resulted in changed plasma ion levels [15].…”

Effects of Herbicides on Fish

“…In one study, 100% mortality was reported upon transfer to seawater after exposure to 0.1 mg atrazine/L for 72 h in freshwater (Moore et al, 2008). In sharp contrast, several other studies have reported that Atlantic salmon smolts were far less sensitive to atrazine at similar or greater concentrations than those reported above (e.g., Moore et al, 2003Moore et al, , 2007Nieves-Puigdoller et al, 2007;Matsumoto et al, 2010). These studies showed that substantially greater concentrations of atrazine were required to cause mortality, perturbations of ion homeostasis in freshwater, some loss of salinity tolerance, and a transient decrease in growth in seawater.…”

“…There were also no differences in the weight or length of the control or atrazine-treated fish after a threemonth grow-out period in seawater (Nieves-Puigdoller et al, 2007). Studies by Matsumoto et al (2010) showed that atrazine at concentrations of up to 100 mg/L had no effect on the survival of Atlantic salmon following a fourday exposure in freshwater and then seven days in seawater.…”

“…Some studies raise significant concerns (Waring and Moore, 2004;Moore et al, 2008), while other research (Moore et al, 2003(Moore et al, , 2007Nieves-Puigdoller et al, 2007;Matsumoto et al, 2010) suggests that the concentrations at which responses to atrazine were observed would rarely be experienced in the environment, especially in lotic systems inhabited by salmonids. Overall, these studies point to the considerable uncertainty about the risks posed by atrazine to Atlantic salmon during smoltification.…”