Relation among reproductive parameters, seasonal variation and mercury accumulation in shrimps xiphopenaeus kroyeri, (Heller, 1862) from the SE Brazilian continental shelf

Abstract

The objective of the present work was to investigate the relations of reproductive parameters (sex and maturity) and seasonality with the accumulation of total mercury in a tropical marine shrimp species (Xiphopenaeus kroyeri) from the north of Rio de Janeiro State, SE, Brazil. These coastal region suffers the influence of the Paraíba do Sul river water discharge. Shrimp samples were monthly collected between and separated by sex and maturity phases. The organisms suffer a specific strong acid digestion (method). Total mercury was analyzed in the extracts with the help of an ICP-EAS with a vapor generating accessory (VGA 77). The studied shrimp species presented an average total Hg concentration of 0.036 μg.g-1. A significant difference was observed between the rainy (spring/summer 0.029 μg.g-1) and the dry period (autumn/winter 0.039 μg.g-1)(p<0.05). The above mentioned results are in accordance with previous studies that described the total Mercury dynamics and transport in the lower RPS drainage basin as well as its estuarine area. Between sex there was no statistical significant difference observed, although a statistical significant difference was observed between the females in distinct maturation states (p<0.05), where the mature females presented higher Hg concentrations (0.043 μg.g-1). The total mercury values observed in the present study was always under the maximum values permitted for human consumption determined by Brazilian Authorities, therefore there is no health risk associated with the consumption of this species by human populations.