Early-warning biomarkers to assess the exposure to atrazine in sea lamprey downstream migrants

Abstract

For decades in Portugal, atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-30 triazine) was one of the most applied herbicide in several crops growth/production and 31 despite being ban in 2007 it is still detected in surface and groundwater. The juvenile 32 sea lamprey may be particularly vulnerable to contaminants such as atrazine as well as 33 others of the group of chloro-s-triazines as it migrates from fresh to the marine 34 environment to start the parasitic phase of the life cycle. This study was carried out to 35 assess if cellular alterations of gill chloride cells and the fatty acid profile of basolateral 36 membrane could be considered as early-warning signals of atrazine presence in the 37 environment. Lampreys were exposed to atrazine at concentrations of 50 and 100 μg/L 38 during acclimation (0 to 35 PSU) and changes in the structure of gill cells, gill 39 Na+K+ATPase activity and phospholipid fatty acid composition of the basolateral 40 membrane system were monitored. The results shown that observed cellular alterations 41 as well as gill cells´ BLM phospholipids fatty acid signature are sensitive to ATZ 42 exposure and could be considered early-warning biomarkers in sea lamprey´s juveniles