Contaminação de Podocnemis unifilis (Testudines: Podocnemididae) por agrotóxicos e mercúrio na bacia do Rio Xingu, Brasil

The occupation policy in the north of the state of Mato Grosso and in the state of Pará, through activities such as gold mining, pasture and subsequent agricultural activities, caused a landscape change and habitat contamination. Pesticides, for example, are on the environment as a result of their use in agriculture and mercury (Hg) is mobilized into the environment through mining, deforestation and biomass burning activities. These contaminants are highly persistent and biomagnifies at each trophic level. Chelonian, because they are long lived organisms can accumulate toxic substances for long periods, are important contamination monitors. Podocnemis unifilis, a chelonian species with wide distribution in the Amazon basin, represent an important resource for riparian and indigenous populations, with wide distribution in the Xingu River basin. This study investigated the landscape changes, contamination of pesticides and Hg in P. unifilis in the Xingu River basin. We selected locations with rivers sources or tributaries in the Xingu River basin, in the states of Mato Grosso and Pará, describing the planted area and the use of pesticides in cotton, sugarcane, corn and soybean crops, as well as deforestation and biomass burned in the historical series from the years 2005 to 2014. Between September and December 2014 fifty specimens of P. unifilis were captured for liver, muscle and adipose tissue. Were evaluated 14 active ingredients of organochlorine pesticides by gas chromatography/electron capture detector (GC/ECD), and total Hg (THg) in the tissues of P. unifilis by cold-vapor atomic absorption (CVAA) spectroscopy. It has been shown that agricultural production as well as the use of pesticides in the Xingu river basin in the state of Mato Grosso are increasing every year, and the most commonly used pesticide was Glyphosate in 2014 (8,055,248 liters). Analyzing the states separately, Glyphosate, Metamidofos, Atrazine, 2,4 D and Endosulfan were the pesticides most used in the state of Mato Grosso and, in Pará state, were Atrazine, Glyphosate, Endosulfan, Chlorpyrifos and Tebuconazole respectively. The states of Mato Grosso and Pará had a significant increase in deforestation and biomass burning between the years researched (2005-2014), especially the city of São Félix do Xingu with 17,686.20 km² deforested only in 2014 and Feliz Natal with a 272% increase in the biomass burning in the last year researched (2014). Eight pesticides were found in the tissues of P. unifilis, including isomers and metabolites (values as mean ± standard deviation): Lindane = 1.39±8.46 ng/g-1; p,p’-DDT = 20.32±24.54 ng/g-1; p,p’-DDD = 4.00±6.96 ng/g-1; p,p’-DDE = 0.95±1.15 ng/g-1; o,p’-DDT = 0.90±3.97 ng/g-1; α-Endosulfan = 3.45±17.73 ng/g-1; β-Endosulfan = 3.81±8.01 ng/g-1; and Endosulfan sulfate = 7.12±12.05 ng/g-1. THg was detected in all specimens (liver: 134.20 μg/g-1, muscle: 24.86 μg/g-1). The type of tissue influenced the concentration of pesticides and THg, and the contamination variations of P. unifilis by pesticides and THg in the tissues were not explained by the interaction between sex and the straight-line carapace length. Comparing the results with current national and international legislation for protein resources, it was verified that the specimens of P. unifilis presented concentrations of pesticides greater than the maximum residue limit for Lindane, ΣDDT and ΣEndosulfan and Hg concentration 100 times greater than the acceptable maximum. It was concluded that the crops are "agrochemical-dependent" and that specimens of P. unifilis are contaminated with organochlorine pesticides and Hg. Riparian and indigenous population of the Xingu River basin that consumes these chelonians may be gradually contaminated, with future consequences for health.A política de ocupação no norte do estado de Mato Grosso e no estado do Pará, através de atividades como mineração, pecuária e posteriormente agricultura, causou a alteração da paisagem e a contaminação do habitat. Os agrotóxicos, por exemplo, estão no ambiente em decorrência de seu uso na agricultura, e o mercúrio (Hg) é mobilizado para o ambiente através das atividades de mineração, desmatamento e queimadas. Estes contaminantes são altamente persistentes e se biomagnificam na cadeia alimentar. Quelônios, por serem organismos de vida longa e poderem acumular substâncias tóxicas por longos períodos, têm se mostrado importantes monitores de contaminação. Podocnemis unifilis, uma espécie de quelônio com ampla distribuição na bacia amazônica, representa um importante recurso proteico para populações ribeirinhas e indígenas, com ampla distribuição na bacia do rio Xingu. Este estudo investigou as alterações da paisagem e a contaminação de agrotóxicos e Hg em P. unifilis na bacia do rio Xingu. Selecionamos localidades que apresentavam nascentes ou afluentes na bacia do rio Xingu, nos estados do Mato Grosso e Pará, sendo descritas quanto à área plantada e o consumo de agrotóxicos nas culturas de algodão, cana-de-açúcar, milho e soja, bem como os focos de calor e desmatamento na série histórica dos anos 2005 a 2014. Entre setembro e dezembro de 2014 cinquenta indivíduos de P. unifilis foram capturados para coleta de amostras de fígado, músculo e tecido adiposo. Avaliamos 14 princípios ativos de agrotóxicos organoclorados, através de um cromatógrafo gasoso com detector de captura de elétrons (GC-ECD) e o Hg total (HgT) nos tecidos de P. unifilis, através de aparelho espetrômetro de absorção atômica vapor a frio. Evidenciou-se que a produção agrícola, bem como o uso de agrotóxicos na bacia do Xingu no estado do Mato Grosso vem aumentando a cada ano, sendo o princípio ativo de agrotóxico mais utilizado o Glifosato em 2014 (8.055.248 litros). Analisando-se os estados separadamente, o Glifosato, Metamidofós, Atrazina, 2,4 D e Endosulfan foram os princípios ativos mais utilizados no estado do Mato Grosso e nos municípios do estado do Pará foram Atrazina, Glifosato, Endosulfan, Clorpirifós e Tebuconazol respectivamente. Os estados do Mato Grosso e do Pará tiveram um aumento significativo no desmatamento e focos de calor entre os anos pesquisados (2005-2014), com destaque para o município de São Félix do Xingu com 17.686,20 km² desmatados apenas em 2014 e Feliz Natal com 272% de aumento nos focos de calor no último ano pesquisado (2014). Foram encontrados oito tipos de agrotóxicos nos tecidos de P. unifilis, incluindo isômeros e metabólitos (valores como média ± desvio padrão): Lindano = 1,39 ± 8,46 ng/g-1; pp`DDT = 20,32 ± 24,54 ng/g-1; pp`DDD = 4,00 ± 6,96 ng/g-1; pp`DDE = 0,95 ± 1,15 ng/g-1; op`DDT = 0,90 ± 3,97 ng/g-1; α-Endosulfan = 3,45 ± 17,73 ng/g-1; β-Endosulfan = 3,81 ± 8,01 ng/g-1; e Sulfato de Endosulfan = 7,12 ± 12,05 ng/g-1. Detectamos HgT em todos os indivíduos (fígado: 134,20 μg/g-1; músculo: 24,86 μg/g-1). O tipo de tecido influenciou na concentração de agrotóxicos e Hg, sendo que as variações da contaminação de P. unifilis por agrotóxicos e Hg nos tecidos não foram explicadas pela interação entre o sexo e o comprimento retilíneo da carapaça. Comparando-se os resultados com a legislação vigente nacional e internacional para recursos proteicos, verificamos que os indivíduos de P. unifilis apresentaram concentrações de agrotóxicos maiores que o limite máximo de resíduo para Lindano e ΣEndosulfan e concentração de Hg 100 vezes superior ao máximo aceitável. Concluímos que as culturas são "agroquímico-dependentes“ e que os indivíduos de P. unifilis estão contaminados por agrotóxicos organoclorados e Hg. A população ribeirinha e indígena da bacia do rio Xingu que consome estes quelônios pode estar sendo gradativamente contaminada, com consequências futuras para saúde

Reproductive allometry of Podocnemis unifilis (Testudines: Podocnemididae) in the flooded forest portion of lower Amazon River, Santarém, Pará, Brazil

O tamanho do corpo dos organismos representa um parâmetro importante, podendo gerar consequências na sua ecologia, atividades reprodutivas, evolução e desenvolvimento. Relação alométrica é o estudo do tamanho (ou do crescimento) de uma parte do corpo relacionado com o tamanho (ou crescimento) total do corpo do organismo. Este estudo analisou a relação alométrica entre as fêmeas de Podocnemis unifilis (Troschel, 1848) e seus ovos e filhotes e entre as características dos ninhos e a ninhada em uma área de várzea do baixo rio Amazonas, Estado do Pará, Brasil. As ninhadas de P. unifilis foram monitoradas no Tabuleiro da Água Preta durante o período reprodutivo de 2009. As fêmeas encontradas desovando foram medidas e seus respectivos ninhos marcados com estacas numeradas e as características físicas mensuradas. Os ovos e filhotes destes ninhos foram retirados e contados, e tiveram seus dados biométricos tomados. Os parâmetros das fêmeas analisados (comprimento retilíneo da carapaça e massa) correlacionaram-se fortemente às variáveis dos ovos (variável x) e filhotes (variável y), exceto com o comprimento do ovo e com a massa do filhote. Estudos futuros direcionados para melhor compreensão de como as características ambientais influenciam nas ninhadas podem ser aplicados, sendo úteis no manejo da espécie.ABSTRACT: The body size of the organisms represents an important parameter, which may have consequences on their ecology, reproductive activities, evolution and development. Allometry relationship is the study of the size (or growth) of a body part in relation to the final size (or growth) of the organism. This study analyzed the allometric relationships between females of Podocnemis unifilis (Troschel, 1848), their eggs and hatchlings, and between nest features and the clutch in the flooded forest portion (várzea) of lower Amazon River, Santarém, state of Pará, Brazil. Podocnemis unifilis clutches' were monitored in the Tabuleiro da Água Preta during the reproductive cycle of 2009. The females found nesting were measured and the physical features of the nests were measured, and the latter were also marked with numbered stakes. The eggs and hatchlings of these nests were removed and counted, and their biometry was performed. The female parameters analyzed (straight-line carapace length and mass) were correlated with almost all the egg and hatchling variables, with the exception of the egg length and the hatchling mass. Future studies directed to the better understanding of how the environmental features influence nest features can be applied, being useful for more effective applications of management actions for the species

Levels of organochlorine pesticides in Amazon turtle (Podocnemis unifilis) in the Xingu River, Brazil

Universidade Federal do Pará. Programa de Pós-graduação em Zoologia. Belém, PA, Brasil / Museu Paraense Emílio Goeldi. Coordenação de Zoologia. Belém, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Toxicologia. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Toxicologia. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Toxicologia. Ananindeua, PA, Brasil.Universidade Federal de Mato Grosso. Instituto de Saúde Coletiva. Cuiabá, MT, Brazil.Universidade Federal do Pará. Núcleo de Altos Estudos Amazônicos. Belém, PA, Brazil.Due to the toxicity and high environmental persistence of organochlorine pesticides in aquatic organisms, turtles have been studied as environment biomonitors. These animals are important sources of protein for the riverside and indigenous peoples of the Brazilian amazon. In the present study, organochlorine pesticide contamination was investigated in Podocnemis unifilis. Liver, muscle and fatty tissue samples were removed from 50 specimens collected from five sampling points located in the Xingu River basin. Fourteen organochlorine pesticides were analysed via gas chromatography with an electron capture detector (CG-ECD). Eight organochlorine pesticides were detected with average concentrations of ∑DDT, ∑Endossulfan and ∑HCH which were 26.17 ± 26.35, 14.38 ± 23.77 and 1.39 ± 8.46 ng g−1 in moisture content, respectively. DDT compounds were the most predominant, with a greater concentration of pp′-DDT in the liver and pp′-DDD in the muscle. Significant differences were noted between the types of tissues studied, and the concentration of OCPs varied between sampling sites

Assessment of Mercury Concentration in Turtles (Podocnemis unifilis) in the Xingu River Basin, Brazil

Many studies on mercury contamination in aquatic biota deal with the effect of consuming metal-contaminated organisms on human health. In this study, we examined the factors that cause mercury contamination in Podocnemis unifilis in the Xingu River Basin of Mato Grosso and Pará States, Brazil. We quantified by atomic absorption spectroscopy with cold vapor the total mercury (THg) content in the liver and muscle samples of 50 Podocnemis unifilis specimens collected from the basin. The liver and muscle samples contained 134.20 ± 119.30 ng g−1 THg and 24.86 ± 26.36 ng g−1 THg, respectively. Each chelonian or meal has, on average, 5.34× more Hg than the highest level established as acceptable. From the results it can be inferred that, given the weekly consumption of chelonians, the riverine and indigenous communities in the Xingu River Basin are at risk of chronic consumption of Hg in amounts beyond the acceptable limit. The potential high risk to the health of this population is evident; however, the risk classification needs to be further studied

Effects of community-based management on amazon river turtles: A case study of podocnemis sextuberculata in the Lower Amazon Floodplain, Pará, Brazil

Podocnemis sextuberculata is cited as "vulnerable" on the International Union for Conservation of Nature Red List due to a decline in its population as a result of the intensive exploitation pressure throughout its range. Understanding the effects of environmental characteristics and human activities on turtle populations is essential to improve current conservation programs. We analyzed the abundance of Podocnemis sextuberculata in the lower Amazon, where a management experiment is under way, by comparing neighboring areas with and without community-based management (CBM) initiatives. In addition, we analyzed the influence of environmental variables on the species' abundance. Abundance was measured by captures per unit effort expressed in number of individuals (CPUEN) and biomass (CPUEB). The effects of CBM and environmental variables were tested by General Linear Model analysis. A total of 354 individuals were captured, 321 in the areas under CBM and 33 in areas without CBM. CPUEN and CPUEB were strongly correlated, and their values were about 10-fold higher in the areas carrying out CBM initiatives. The variable that best explained variation in CPUEN and CPUEB was CBM. Distance between the sampling point and the nearest nesting beach and river level also influenced capture rates. Results clearly show that local fishing restrictions can have a positive influence on turtle populations. © 2013 Chelonian Research Foundation