Statistical assessment of background levels for metal contamination from a subtropical estuarine system in the SW Atlantic (Paranaguá Estuarine System, Brazil)

Abstract

Trace metal background levels determination is essential for the proper assessment of the contamination status of a region. This study aims to integrate geochemical and statistical methods for the reliable determination of background levels, applying it to the sediments of the Paranaguá Estuarine System (PES), a large subtropical estuarine system of international importance since it is considered a World Heritage Site and Biosphere Reserve and it harbors the main South American grain shipping port. Prediction Interval (PI) was applied as a chemometric tool to evaluate metal enrichment without a reference level and assess a regional background. Moreover, the sources and concentrations of major and trace elements were assessed in surface sediments from 135 sampling sites located in the Paranaguá Estuarine System (PES). PES surface sediment elements concentrations may be considered lower than those found in other anthropized environments indicating no significant contamination for most of the studied elements (Cr, Cu, Ni, Pb and Zn). The levels of As in the PES may be related to the geochemical characteristics of the adjacent drainage basin and the occurrence of phosphate rocks, which contain As in their composition. However, As was also influenced by anthropogenic inputs either from agricultural activities or fertilizer industries working with mining phosphate in the region. KeywordsMajor and trace elements • World Heritage Listed area • Background levels • Chemometric tool

Influence of the “Great Acceleration” of the Anthropocene on the fluxes of trace elements in sediments of the Santos and São Vicente estuarine system, southeastern Brazil

“…Compared to metal concentrations reported in surface sediments and sediment cores in other Brazilian coasts (Table 2), the present concentrations were relatively low. Trace element concentrations found in this study were comparable with a previous research conducted in the SSVES (Kim et al 2018) and Paranaguá Bay (Angeli et al 2020), another important port impacted area. The trace element concentrations were also, comparable to the levels found in the Caravelas estuary (Angeli et al 2019) and Todos os Santos Bay (Hatje and Barros 2012), both located on Northeastern Brazilian coast and considered relatively preserved, despite the latter showing significant levels of Zn contamination.…”

“…The PCA was conducted to investigate the interrelationships between variables and to evaluate the possible sources of trace elements. Many researchers (Rubio et al 2000;Filgueiras et al 2004;Geng et al 2015;Varol et al 2020;Hosokawa et al 2020;Angeli et al 2020) have used this technique in the evaluation of environmental data. Statistical analyses were conducted in R Software (RCoreTeam, 2017).…”

“…In the Doce River continental shelf, on Brazilian eastern coast, high As enrichments were attributed to iron and gold mining exploitation (Cagnin et al 2017). In estuarine and lagoonal systems located in Brazil southern coast, As enrichments were found next to port terminals and related to the presence of fertilizer producing plants (Mirlean and Roisemberg 2006;Sá et al 2015;Angeli et al 2020). In the SSVES, fertilizer plants, established in the 1970s, have been operating along the margins of some rivers and disposing a large quantity of phosphogypsum, approximately 400 ton per day, as piles in adjacent storage areas.…”

Macrobenthic community responses to multiple environmental stressors in a subtropical estuary

“…The element with the higher CF and Igeo were Zn, at the Saguaçu lagoon, where the concentrations for this element were higher. When comparing the Babitonga metal levels with other Brazilian estuaries, our levels were higher than found in Paranaguá bay ( Angeli et al, 2020 ), although Paranaguá bay data are from the whole sediment while our data were obtained from the fine fraction only. Therefore, our results are more comparable with Baixada Santista, a highly urbanized and industrialized estuary ( Kim et al, 2018 ), with similar Cr (14.43–103.82 mg.kg −1 ) and Cu (5.5–112.29 mg.kg −1 ) concentrations, higher Ni (5.39–19.7 mg.kg −1 ) and lower Zn (44.74–983.90 mg.kg −1 ) concentrations.…”

Mudbelts do Sul e Sudeste do Brasil: um arquivo geoquímico para investigação de impactos antropogênicos

“…O Itajaí-Açu, em Santa Catarina, possui extensão de 15500 km 2 , com um fluxo variando de 40 -2000 m 2 s -1 (Schettini et al, 1998). A Baía de Paranaguá apresenta uma área se 612 km 2 e, sua maior descarga fluvial, representada pelo Rio Cachoeira, apresenta uma média de 21,13 m 3 s -1 (Angeli et al, 2020). Por fim, a Baía da Babitonga, localizada a nordeste de Joinville, Santa Catarina, cobre uma área de 1400 km 2 .…”