Fluoride content by ion chromatography using a suppressed conductivity detector and osmolality of bitterns discharged into the Pacific Ocean from a saltworks: feasible causal agents in the mortality of green turtles (Chelonia mydas) in the Ojo de Liebre lagoon, Baja California Sur, Mexico.
On December 1997, 94 corpses of green turtles, Chelonia mydas, were found at the Ojo de Liebre lagoon (OLL) adjacent to the industrial operation of Exportadora de Sal S. A (ESSA), the largest saltworks in the world, owned by the Mexican Government and Mitsubishi Corporation, located in Baja California Sur, Mexico. Every year about 551 x 10(6) m3 of seawater is solar evaporated, producing 7 x 10(6) tons of salt and 24.6 x 10(6) m3 of bitterns, the latter being discharged into the OLL, which is a costal lagoon of the Pacific Ocean. ESSA claimed that bitterns contain the same salts present in seawater, but 20-fold more concentrated than the former. Ion chromatography with a conductivity detector and ion suppression was used to determine the F-, Cl-, SO4(2-) and CO3(2-) contents of seawater, brines and bitterns collected at ESSA. Furthermore, the osmolality of brines and bitterns from ESSA was measured. F- content in bitterns was 60.5-fold more than that in seawater. The bitterns osmolality was 11,000 mosm/kg of water, whereas the turtle's plasma osmolality was about 400 mosm/kg of water. We concluded that the dumping of bitterns into the ocean should be avoided.
Tovar
Luis Raúl
LR
Center for Interdisciplinary Research on the Environment and Development, National Polytechnic Institute, México DF, México. lrtovar@avantel.net
Gutiérrez
Ma Eugenia
ME
Cruz
Guillermo
G
D000818:Animals; D002852:Chromatography, Ion Exchange / Q000379:methods*; D004553:Electric Conductivity; D019652:Extraction and Processing Industry / Q000592:standards*; D005459:Fluorides / Q000032:analysis* / Q000633:toxicity*; D008800:Mexico; D009994:Osmolar Concentration; D010140:Pacific Ocean; D012492:Salts; D012623:Seawater / Q000737:chemistry*; D014426:Turtles / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity
D012492:Salts; D014874:Water Pollutants, Chemical; C017082:brine; D005459:Fluorides