Most current bioexposure assessments for UV filters focus on contaminants concentrations in fish from river and lake. To date there is not information available on the occurrence of UV filters in ...marine mammals. This is the first study to investigate the presence of sunscreen agents in tissue liver of Franciscana dolphin (Pontoporia blainvillei), a species under special measures for conservation. Fifty six liver tissue samples were taken from dead individuals accidentally caught or found stranded along the Brazilian coastal area (six states). The extensively used octocrylene (2-ethylhexyl-2-cyano-3,3-diphenyl-2-propenoate, OCT) was frequently found in the samples investigated (21 out of 56) at concentrations in the range 89–782 ng·g–1 lipid weight. São Paulo was found to be the most polluted area (70% frequency of detection). Nevertheless, the highest concentration was observed in the dolphins from Rio Grande do Sul (42% frequency of detection within that area). These findings constitute the first data reported on the occurrence of UV filters in marine mammals worldwide.
Blubber samples from three delphinid species (false killer whale, Guiana and rough-toothed dolphin), as well as liver samples from franciscana dolphins were analyzed for dioxins and related compounds ...(DRCs). Samples were collected from 35 cetaceans stranded or incidentally captured in a highly industrialized and urbanized area (Southeast and Southern Brazilian regions). Dioxin-like PCBs accounted for over 83% of the total TEQ for all cetaceans. Non-ortho coplanar PCBs, for franciscanas (82%), and mono-ortho PCBs (up to 80%), for delphinids, constituted the groups of highest contribution to total TEQ. Regarding franciscana dolphins, significant negative correlations were found between total length (TL) and three variables, ΣTEQ-DRCs, ΣTEQ-PCDF and ΣTEQ non-ortho PCB. An increasing efficiency of the detoxifying activity with the growth of the animal may be a plausible explanation for these findings. This hypothesis is reinforced by the significant negative correlation found between TL and PCB126/PCB169 concentration ratio. DRC concentrations (ng/glipids) varied from 36 to 3006, for franciscana dolphins, as well as from 356 to 30,776, for delphinids. The sum of dioxin-like and indicator PCBs varied from 34,662 to 279,407ng/glipids, for Guiana dolphins from Rio de Janeiro state, which are among the highest PCB concentrations ever reported for cetaceans. The high concentrations found in our study raise concern not only on the conservation of Brazilian coastal cetaceans, but also on the possibility of human health problem due to consumption of fish from Brazilian estuaries.
•Dioxin-like PCBs accounted for over 83% of the total TEQ for all cetaceans•Negative correlations were found between length and TEQ values in franciscanas.•PCB concentrations found are among the highest ever reported for cetaceans.
Pyrethroids (PYR) and UV filters (UVF) were investigated in tissues of paired mother-fetus dolphins from Brazilian coast in order to investigate the possibility of maternal transfer of these emerging ...contaminants. Comparison of PYR and UVF concentrations in maternal and fetal blubber revealed Franciscana transferred efficiently both contaminants to fetuses (F/M > 1) and Guiana dolphin transferred efficiently PYR to fetuses (F/M > 1) different than UVF (F/M < 1). PYR and UVF concentrations in fetuses were the highest-ever reported in biota (up to 6640 and 11,530 ng/g lw, respectively). Muscle was the organ with the highest PYR and UVF concentrations (p < 0.001), suggesting that these two classes of emerging contaminants may have more affinity for proteins than for lipids. The high PYR and UVF concentrations found in fetuses demonstrate these compounds are efficiently transferred through placenta. This study is the first to report maternal transfer of pyrethroids and UV filters in marine mammals.
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•First time maternal transfer of pyrethroids and UV filters in mammals was reported.•Pollutants in fetus tissues characterize their transplacental transfer.•Fetuses had pyrethroid and UV filter levels 10 times higher than their mothers.•Muscle was the organ presented with the highest concentrations of PYR and UVF.
Pyrethroids and UV filter concentrations in fetus and mother dolphin tissues demonstrated placenta and milk transfer in marine mammals.
River dolphins are a highly threatened polyphyletic group comprised of four odontocete families: Iniidae, Pontoporiidae, Lipotidae, and Platanistidae, the first two endemic to South America. To ...address the knowledge gap regarding infectious agents in this cetacean group, we surveyed the presence of herpesviruses by PCR in skin and/or blood samples of live-captured Amazon (Inia geoffrensis, n = 25) and Bolivian (Inia boliviensis, n = 22) river dolphins of the Amazon basin and in selected tissue samples of franciscanas (Pontoporia blainvillei, n = 27) stranded or bycaught in southeastern Brazil. Additionally, available franciscana tissue samples were examined by histopathology. Herpesvirus DNA was amplified in 13 Bolivian river dolphins (59.1%, 95% CI 38.5-79.6%) and 14 franciscanas (51.9%, 95% CI 33.0-70.7%). All Amazon river dolphins were herpesvirus-negative. Two different herpesviruses were found in Bolivian river dolphins: a previously known gammaherpesvirus detected in blood and/or skin samples of all positive individuals and a novel alphaherpesvirus in the skin of one animal. A new gammaherpesvirus was found in several franciscana samples-the first herpesvirus recorded in Pontoporiidae. Intranuclear inclusion bodies consistent with herpesvirus were observed in the lymph node of one franciscana. The high divergence among the obtained herpesviruses and those previously described can be explained by viral-host coevolution, and by the fact that these populations are fairly isolated.
Liver samples from 53 Franciscana dolphins along the Brazilian coast were analyzed for organobrominated compounds. Target substances included the following anthropogenic pollutants: polybrominated ...diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), as well as the naturally-generated methoxylated-PBDEs (MeO-PBDEs). PBDE concentrations ranged from 6 to 1797 ng/g lw (mean 166 ± 298 ng/g lw) and were similar to those observed in cetaceans from Northern Hemisphere. PBBs were found in all sampling locations (<LOQ to 57 ng/g lw). DBDPE was detected in 42% of the dolphins from the most industrialized Brazilian state and the concentrations ranging from <LOQ to 352 ng/g lw. Franciscana dolphins from the tropical Brazilian shore presented the highest MeO-PBDE concentrations ever reported for coastal cetaceans (up to 14 μg/g lw). Eight MeO-PBDE congeners were detected and the present investigation constituted the first record of occurrence of six of them in marine mammal livers.
► PBDE, emerging BFR and MeO-PBDE levels in Franciscana dolphin from Brazil were reported. ► Six MeO-PBDEs were detected for the first time in marine mammals. ► PBDE contamination was similar than those from other industrialized areas around the world. ► MeO-PBDEs presented the higher concentrations found in coastal biota worldwide.
Concentrations and accumulation profiles of PBDEs, MeO-PBDEs and emerging brominated compounds in livers of dolphins from South Atlantic.
The present study constitutes the first investigation to demonstrate pyrethroid bioaccumulation in marine mammals, despite the assumption that these insecticides are converted to non-toxic ...metabolites by hydrolysis in mammals. Twelve pyrethroids were determined in liver samples from 23 male franciscana dolphins from Brazil. The median concentration values for total pyrethroids were 7.04 and 68.4ng/g lw in adults and calves, respectively. Permethrin was the predominant compound, contributing for 55% of the total pyrethroids. Results showed a distinct metabolic balance of pyrethroids through dolphin life. High loads are received at the beginning of their lives and, when they reach sexual maturity, these mammals seem to degrade/metabolize pyrethroids. Maternal transfer of these compounds was also evaluated through the analysis of breast milk and placenta samples. Pyrethroids were detected in both matrices, with values between 2.53–4.77ng/g lw and 331–1812ng/g lw, respectively. Therefore, for the first time, a study shows mother-to-calf transfer of pyrethroids by both gestational and lactation pathways in dolphins.
The present study constitutes the first investigation to demonstrate pyrethroid bioaccumulation in marine mammals, despite the assumption that these insecticides are converted to non-toxic metabolites by hydrolysis in mammals. Twelve pyrethroids were determined in liver samples from 23 male franciscana dolphins from Brazil. The median concentration values for total pyrethroids were 7.04 and68.4 ng/g lw in adults and calves, respectively. Permethrin was the predominant compound, contributing for 55% of the total pyrethroids. Results showed a distinct metabolic balance of pyrethroids through dolphin life. High loads are received at the beginning of their lives and, when they reach sexual maturity, these mammals seem to degrade/metabolize pyrethroids. Maternal transfer of these compounds was also evaluated through the analysis of breast milk and placenta samples. Pyrethroids were detected in both matrices, with values between 2.53–4.77ng/g lw and 331–1812ng/g lw, respectively. Therefore, for the first time, a study shows mother-to-calf transfer of pyrethroids by both gestational and lactation pathways in dolphins. Display omitted
► For the first time, the presence of pyrethroids in marine mammals was reported, supporting their bioaccumulation. ► A distinct metabolic balance of pyrethroids through dolphin life was hypothesized. ► For the first time, maternal transfer of pyrethroids by both gestational and lactation pathways was observed.
Pontoporia blainvillei
(Gervais & d’Orbigny, 1844), the franciscana dolphin, is the most endangered small cetacean in the Western South Atlantic. It is an endemic species with a coastal and estuarine ...distribution that has been divided into four Franciscana Management Areas (FMAs). We used the mitochondrial DNA control region to conduct a phylogeographic analysis to evaluate the population structure of the franciscana and the influence of paleoceanographic events on its biogeographic history. We found nine populations along the entire distribution (Φ
ST
= 0.41, Φ
CT
= 0.38, p < 10
–5
), with estimated migration rates resulting in less than one female per generation. Populations from FMAIII and FMAIV in the south (including the Río de La Plata Estuary) showed higher long-term migration rates and effective population sizes than northern populations. The phylogeographic analysis supports the franciscana origin in the Río de La Plata Estuary, with further dispersal south and northwards. The first lineage split happened around 2.5 Ma, with lineage radiation throughout the Pleistocene until recent fragmentation events shaped current-day populations. We suggest that Pleistocene glaciations influenced the dispersion and population structure of the franciscana. Specifically, that the shift of the Brazil-Malvinas Confluence drove the dispersion northwards. Then, low sea-level periods caused either the isolation in estuarine refugia or local extinctions, followed by re-colonizations.
Summary
Brucella‐exposure and infection is increasingly recognized in marine mammals worldwide. To better understand the epidemiology and health impacts of Brucella spp. in marine mammals of Brazil, ...molecular (conventional PCR and/or real‐time PCR), serological (Rose Bengal Test RBT, Competitive cELISA, Serum Agglutination Test SAT), pathological, immunohistochemical (IHC) and/or microbiological investigations were conducted in samples of 129 stranded or by‐caught marine mammals (orders Cetartiodactyla n = 124, Carnivora n = 4 and Sirenia n = 1). Previous serological tests performed on available sera of 27 of the 129 animals (26 cetaceans and one manatee), indicated 10 seropositive cetaceans. Conventional PCR and/or real‐time PCR performed in cases with available organs (n = 119) and/or blood or swabs (n = 10) revealed 4/129 (3.1%) Brucella‐infected cetaceans (one of them with positive serology; the remaining three with no available sera). Pathological, IHC and/or microbiological analyses conducted in PCR/real‐time PCR and/or seropositive cases (n = 13) revealed Brucella‐type lesions, including meningitis/meningoencephalitis, pneumonia, necrotizing hepatitis, pericarditis and osteoarthritis in some of those animals, and positive IHC was found in all of them (excepting two live‐stranded animals without available organs). Brucella spp. culture attempts were unsuccessful. Our results demonstrated exposure, asymptomatic, acute and chronic Brucella sp. infection in several cetacean species in the Brazilian coast, highlighting the role of this pathogen in stranding and/or death, particularly in Clymene dolphin (Stenella clymene) and short‐finned pilot whale (Globicephala macrorhynchus) off Ceará State. Novel hosts susceptible to Brucella included the franciscana (Pontoporia blainvillei), the Guiana dolphin (Sotalia guianensis) and the spinner dolphin (Stenella longirostris). Additionally, three coinfection cases involving Brucella spp. and cetacean morbillivirus, Edwarsiella tarda and Proteus mirabilis were detected. To the best of our knowledge, this is the first long‐term and large‐scale survey of Brucella spp. in marine mammals of South America, widening the spectrum of susceptible hosts and geographical distribution range of this agent with zoonotic potential.
Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii. In cetaceans, T. gondii infection is a significant cause of morbidity and mortality. Despite the worldwide range and ...broad cetacean host record of T. gondii infection, there is limited information on toxoplasmosis in cetaceans from the Southern hemisphere. We investigated the occurrence of T. gondii by histopathology and immunohistochemistry in tissue samples of 185 animals comprising 20 different cetacean species from Brazil. Three out of 185 (1.6%) animals presented T. gondii-associated lesions: a captive killer whale Orcinus orca, a free-ranging common bottlenose dolphin Tursiops truncatus and a free-ranging Guiana dolphin Sotalia guianensis. The main lesions observed in these animals were necrotizing hepatitis, adrenalitis and lymphadenitis associated with protozoal cysts or extracellular tachyzoites presenting immunolabeling with anti-T. gondii antibodies. This study widens the spectrum of species and the geographic range of this agent in Brazil, and provides the first reports of T. gondii infection in a captive killer whale and in a free-ranging common bottlenose dolphin in South America.
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