Impact of metals derived from passive mining wastes on the crab Neohelice granulata from the Natural Protected Area San Antonio bay, Rio Negro.

GIARRATANO E.; MARINHO CH; MALANGA G.; GIL MN

CABA

Congreso; SETAC 2015 Latin American 11th Biennial Meeting; 2015

The Natural Protected Area San Antonio bay is of particular importance for its congregation of migratory shorebirds and has been declared one of the Western Hemisphere Shorebird Reserve Network (WHSRN) International sites. In the Patagonian coastal area there are virtually no mining activities releasing metals into the environment, except for San Antonio Bay in the northwest of San Matías gulf until 1980. High levels of Pb, Cu, Zn and Cd have been found in sediments, mussels and crabs evidencing that waste piles from the abandoned mine are still leaching various metals to the environment. Crab Neohelice granulata has important ecological roles controlling different physicochemical and biological aspects in mudflats and salt marshes and it is also considered a key species in the energy transfer. Present study represents the first assessment of variation on oxidative stress biomarkers in N. granulata from San Antonio bay under field conditions, associated mainly to metal contamination coming from passive mining wastes. Three sites were sampled within this sea inlet: close to the waste pile, in front of a fish plant and in the port area. Punta Perdices located at the southeast of the bay was considered as a control site. Metal accumulation and biomarkers such as small antioxidant molecules (α-tocopherol ), oxidative damage (lipid radical), antioxidant enzymes (catalase and glutathione-S-transferase) and metallothionein content in tissues of male crab N. granulata were determined three monthly from November 2012 to August 2013. Accumulation of Ni, Zn, Cr and Al varied only with seasons although without a constant trend, meanwhile Cd, Cu and Pb also varied among sites being higher in Pile and Port. Biochemical results indicated that variations in catalase activity was only site specific being maximum in Pile; meanwhile lipid radical, α-tocopherol and metallothioneins were only seasonal specific being higher in autumn and winter. In general, biochemical responses were inversely related to some metals (Ni,Cr, Pb and Cu). Results evidenced that crabs still accumulate high concentrations of metals deposited long time ago having the potential to affect not only themselves, but also be passed up food chains. Considering the differences in species sensitivity to toxicants, levels of metals in San Antonio could represent a potential factor reducing the biodiversity of this Natural Protected Area