Sublethal effects of atrazine on embryo-larval development of Rhinella arenarum (Anura: Bufonidae)

Atrazine (ATR), one of the most widely used herbicides in the world, affects not only target organisms but also the biota in general. Here, the teratogenic and neurotoxic effects of ATR on Rhinella arenarum (South American toad) embryos, and larvae were evaluated by means of standardized bioassays during acute and chronic exposures. The herbicide had a significant incidence of malformations, with a Teratogenic Index (TI) of 3.28. The main effects were delayed development, reduced body size, microcephaly, axial flexures, wavy tail and edema. In addition, delayed development, reduced development of forelimbs, and edema were recorded at metamorphosis stages. Scanning electron microscopy allowed observing different degrees of cellular dissociation and persistent cilliar cells in specific regions like the adhesive structure and tail fin. Results obtained by ATR 24 h pulse exposures at six developmental stages pointed out blastula as the most susceptible developmental stage both for immediate and delayed adverse effects. A noteworthy recovery capacity from acute toxic effects was recorded from the neural plate stage onwards. Regarding neurotoxic effects, abnormal, and erratic swimming and spasmodic contractions were recorded. Both the teratogenic and neurotoxic effects reported in this study demonstrate the importance of evaluating sublethal effects in non-target organisms as they could imply reduced fitness of individuals and eventually a population decline. The Hazard Quotients (HQ) for ATR ranged from 0.14 to 10.80, and the fact that some of these values are above USEPA's level of concern indicate that ATR is likely a risk to R. arenarum.Fil: Svartz, Gabriela Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Pro Salud y Medio Ambiente; ArgentinaFil: Herkovits, Jorge. Fundación Pro Salud y Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Perez Coll, Cristina Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentin

Sustainable pome fruit production in Patagonia, Argentina

Apple and pear production in Argentina mostly takes place in the provinces of Río Negro and Neuquén, along a valley located in an area irrigated by the rivers Neuquén, Limay and Negro. Most commonly agrochemicals applied for these cultures protection are pesticides against mite and codling moth (Cydiapomonella, L). Carbaryl,azinphos-methyl and dimethoate have been recently detected and quantified in water samples from these rivers. Heptachlor, was also found sporadically, despite its use is forbidden in our country. Although these organophosphorus pesticides use is allowed, dimethoate and azinphos-methyl, as well as carbaryl are harmful substances that exert adverse effects through inhibition of cholinesterases and carboxylesterases. Also they are responsible of eliciting antioxidant responses in different organisms. Fruit production in this region became more sustainable in the last years as the consequence of government prohibition on the use of old generation pesticides and the introduction of new generation ones. A National Program designed to avoid codling moth damage, through a sexual confusion method, was implemented in 2006. The codling moth induced damage reached 6,1% of total production in 2003 in farms that were afterwards included in the Program, and 0,73% of it, after 3 years of program development; and at the same time there was a 385 ton/year decrease in azimphos-methyl use. Improvement in management techniques for pests as San José louse and European red mite, as well as government programs for their control promoting the use of non-toxic natural compounds, will certainly contribute to achieve sustainable fruit production in Patagonia.Fil: Sfara, Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; ArgentinaFil: Fonovich, Teresa Mabel. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; ArgentinaFil: Perez Coll, Cristina Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentin

Developmental toxicity and risk assessment of nonylphenol to the South American toad, Rhinella arenarum

The toxicity of Nonylphenol, an emerging pollutant, on the common South American toad Rhinella arenarum was stage and time dependent, thus Median Lethal Concentrations (LC50) for acute (96 h), short-term chronic (168 h) and chronic exposure (336 h) were 1.06; 0.96 and 0.17 mgNP/L from embryonic period (S.4), whereas for exposure from larvae (S.25), LC50 remained constant at 0.37 mgNP/L from 96 h to 168 h, decreasing to 0.11 mgNP/L at 336 h. NOEC-168 h for exposure from embryos was 0.025 mgNP/L. The Teratogenic Potential (NOEC-lethality/NOEC-sublethal effects) was 23 times higher than the threshold value, indicating a high risk for embryos to be malformed in absence of significant lethality and representing a threat for the species conservation. By comparing with other amphibians, the early development of R. arenarum was very sensitive to NP. The results highlight the relevance of extending the exposure time and look for the most sensitive stage in order to perform the bioassays for conservation purposes.Fil: Aronzon, Carolina Mariel. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Babay, Paola Alejandra. Comisión Nacional de Energía Atómica; ArgentinaFil: Perez Coll, Cristina Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental; Argentin

Synergistic effects of glyphosate- and 2,4-D-based pesticides mixtures on Rhinella arenarum larvae

Glyphosate and 2,4-D are two herbicides commonly used together. Since there is little information about the interactions between these pesticides, the aim of this study was to evaluate the single and joint lethal toxicity of the glyphosate-based herbicide (GBH) ATANOR® (43.8% of glyphosate, isopropylamine salt) and the 2,4-D-based herbicide (2,4-DBH) Así Max 50® (602000 mg/L of 2,4-D) on Rhinella arenarum larvae. Equitoxic and non-equitoxic mixtures were prepared according to the recommendation for their combination and analyzed with a fixed ratio design at different exposure times and levels of lethality (LC10, LC50, and LC90). GBH (504h-LC50=38.67 mg ae/L) was significantly more toxic than 2,4-DBH (504h-LC50=250.31 mg ae/L) and their toxicity was time-dependent. At 48h, the equitoxic mixture toxicity was additive and from the 96h was antagonistic at LC10 and LC50 effect level. The non-equitoxic mixture toxicity was additive at LC10 effect level from the 48h to the 168h, and synergistic from the 240h. At LC50 and LC90 effect level, the mixture interaction resulted synergistic for all exposure times. This is the first study to report the synergistic interactions between GBH and 2,4-DBH on amphibians, alerting about its negative impact on aquatic ecosystems.Fil: Peluso, Julieta. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Furió Lanuza, Agustina. Universidad Nacional de San Martín; ArgentinaFil: Perez Coll, Cristina Silvia. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Aronzon, Carolina Mariel. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; Argentin

Stage dependent susceptibility to Copper in Rhinella arenarum embryos and larvae

Copper toxicity in different embryonic and larval stages of the common South American toad Rhinella arenarum was evaluated by means of continuous and 24-h pulse treatments in 12 different developmental stages. Lethal concentrations (LC) of 10, 50, and 90% of continuous treatment with Cu from early blastula (S.4), complete operculum (S.25), and hind limb bud (S.28) stages were plotted from 24 to 168 h, resulting from S.4 in a 24-h LC50 of 137 mg Cu2þ/L and a 168-h LC50 of 19.5mg Cu2þ/L. This result was in agreement with pulse treatments that showed a high resistance to Cu at blastula and gastrula stages, whereas the organogenic period, between muscular response (S.18) and open mouth (S.21), was very susceptible to this metal. Continuous treatments from S.25 showed no significant differences along exposure time (168-h LC50¼51mg Cu2þ/L), but in the case of S.28 toxicity increased slightly from a 24-h LC50 of 138.6 mg Cu2þ/L to a 168-h LC50 of 104 mg Cu2þ/L, pointing out that, although the larval period was significantly more resistant to Cu, there was also a remarkable stage-dependent susceptibility to this metal. Copper teratogenic potential was approximately two, and main adverse effects were reduced body size, axial flexure, microcephaly, acephaly, mouth malformations, agenesis of or underdeveloped gills, agenesis of or underdeveloped tail, and hydropsy. The results are discussed considering Cu toxicity mechanisms, an evolutionary perspective, and environmental protection.Fil: Aronzon, Carolina Mariel. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sandoval, María Teresa. Universidad Nacional del Nordeste; ArgentinaFil: Herkovits, Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Perez Coll, Cristina Silvia. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Estudio de indicadores fisicoquímicos y toxicológicos del agua superficial del bajo Río Paraná

La cuenca baja del Río Paraná comprende un sistema de humedales que albergan un reservorio vital de biodiversidad y uno de los ecosistemas más productivos del planeta, brindando además importantes beneficios económicos y sociales. En el tramo final del bajo Paraná se desarrollan actividades agropecuarias e industriales que generan importantes impactos ambientales. En particular, el Arroyo de la Cruz (S1) atraviesa el partido de Campana que se caracteriza por una alta actividad industrial. El Río Arrecifes (S2) se caracteriza por atravesar grandes extensiones de cultivos. Por otro lado, los anfibios se destacan como valiosos indicadores de la calidad ambiental, desempeñando múltiples roles en los ecosistemas. El objetivo del presente trabajo fue evaluar en forma preliminar la calidad del agua superficial en S1 y S2 midiendo parámetros fisicoquímicos (Temperatura, Oxígeno Disuelto, pH, profundidad, conductividad, sólidos suspendidos totales, DBO5, DQO, amonio, fosfatos, nitratos, nitritos, cloruros), metales (As, Cr, Cu, Ni, Pb, Zn), y mediante bioensayos estandarizados de toxicidad (ANFITOX) con un anfibio autóctono Rhinella arenarum(Ra), por exposición de 10 embriones (E.4) o larvas (E.25), por triplicado, a diluciones de las muestras compuestas de agua superficial de cada sitio durante 504h y a un control negativo de Solución ANFITOX. Se destacaron los bajos valores de OD de los dos sitios: S1=3,4 y S2=4,1(mg/L). En cuanto a los metales, las concentraciones de Cu fueron mayores a lo reglamentado (decreto 831/93). Cabe destacar la letalidad observada por exposición de organismos en ambos estadios a las muestras ambientales. En el periodo embrionario, S1 causó mayor mortalidad, mientras que en la etapa larval, S2 fue más tóxica. Este estudio alerta sobre la degradación del Río Paraná en su cuenca baja y las herramientas empleadas podrían usarse para la toma de decisiones a fin de proteger los humedales.Fil: Peluso, Julieta. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Aronzon, Carolina Mariel. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Perez Coll, Cristina Silvia. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; Argentin

Stress and worry in the 2020 coronavirus pandemic: Relationships to trust and compliance with preventive measures across 48 countries in the COVIDiSTRESS global survey

The COVIDiSTRESS global survey collects data on early human responses to the 2020 COVID-19 pandemic from 173 429 respondents in 48 countries. The open science study was co-designed by an international consortium of researchers to investigate how psychological responses differ across countries and cultures, and how this has impacted behaviour, coping and trust in government efforts to slow the spread of the virus. Starting in March 2020, COVIDiSTRESS leveraged the convenience of unpaid online recruitment to generate public data. The objective of the present analysis is to understand relationships between psychological responses in the early months of global coronavirus restrictions and help understand how different government measures succeed or fail in changing public behaviour. There were variations between and within countries. Although Western Europeans registered as more concerned over COVID-19, more stressed, and having slightly more trust in the governments' efforts, there was no clear geographical pattern in compliance with behavioural measures. Detailed plots illustrating between-countries differences are provided. Using both traditional and Bayesian analyses, we found that individuals who worried about getting sick worked harder to protect themselves and others. However, concern about the coronavirus itself did not account for all of the variances in experienced stress during the early months of COVID-19 restrictions. More alarmingly, such stress was associated with less compliance. Further, those most concerned over the coronavirus trusted in government measures primarily where policies were strict. While concern over a disease is a source of mental distress, other factors including strictness of protective measures, social support and personal lockdown conditions must also be taken into consideration to fully appreciate the psychological impact of COVID-19 and to understand why some people fail to follow behavioural guidelines intended to protect themselves and others from infection. The Stage 1 manuscript associated with this submission received in-principle acceptance (IPA) on 18 May 2020. Following IPA, the accepted Stage 1 version of the manuscript was preregistered on the Open Science Framework at https://osf.io/g2t3b. This preregistration was performed prior to data analysis

Stress and worry in the 2020 coronavirus pandemic: relationships to trust and compliance with preventive measures across 48 countries in the COVIDiSTRESS global survey

The COVIDiSTRESS global survey collects data on early human responses to the 2020 COVID-19 pandemic from 173 429 respondents in 48 countries. The open science study was co-designed by an international consortium of researchers to investigate how psychological responses differ across countries and cultures, and how this has impacted behaviour, coping and trust in government efforts to slow the spread of the virus. Starting in March 2020, COVIDiSTRESS leveraged the convenience of unpaid online recruitment to generate public data. The objective of the present analysis is to understand relationships between psychological responses in the early months of global coronavirus restrictions and help understand how different government measures succeed or fail in changing public behaviour. There were variations between and within countries. Although Western Europeans registered as more concerned over COVID-19, more stressed, and having slightly more trust in the governments' efforts, there was no clear geographical pattern in compliance with behavioural measures. Detailed plots illustrating between-countries differences are provided. Using both traditional and Bayesian analyses, we found that individuals who worried about getting sick worked harder to protect themselves and others. However, concern about the coronavirus itself did not account for all of the variances in experienced stress during the early months of COVID-19 restrictions. More alarmingly, such stress was associated with less compliance. Further, those most concerned over the coronavirus trusted in government measures primarily where policies were strict. While concern over a disease is a source of mental distress, other factors including strictness of protective measures, social support and personal lockdown conditions must also be taken into consideration to fully appreciate the psychological impact of COVID-19 and to understand why some people fail to follow behavioural guidelines intended to protect themselves and others from infection. The Stage 1 manuscript associated with this submission received in-principle acceptance (IPA) on 18 May 2020. Following IPA, the accepted Stage 1 version of the manuscript was preregistered on the Open Science Framework at https://osf.io/g2t3b. This preregistration was performed prior to data analysis

Comparative toxicity of cypermethrin and a commercial formulation on Rhinella arenarum larval development (Anura: Bufonidae)

In this study we reported the effects of cypermethrin (CY), a growing use insecticide, comparing the toxicity of the active ingredient (AI) and a commercial formulation (CF) on a non-target organism, Rhinella arenarum. The results showed a highly significant increase (p<0.05) in the toxicity of both substances over time, obtaining a 96 h LC-50 of 28.07 mg CY/L and 11.20 mg CY/L, and a 336 h LC-50 of 0.0048 mg CY/L and 0.00065 mg CY/L, for AI and CF respectively. Furthermore, the toxicity of CF was greater than AI at all exposure periods, reaching up to 7 times. The main sublethal effects were associated with alterations in behaviour as hyperkinesia and spasmodic contractions up to total absence of movements. Considering these results and the obtained by means of the risk assessment conducted, we can conclude that this pesticide represents a potential direct risk considering lethality, or indirect by means of its sublethal effects for the survival of this amphibian in agroecosystems.Fil: Svartz, Gabriela Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; ArgentinaFil: Perez Coll, Cristina Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentin

Assessment of environmental quality of water bodies next to agricultural areas of Buenos Aires province (Argentina) by means of ecotoxicological studies with Rhinella arenarum

Little is known about the effects of polluted water bodies from Buenos Aires Province on the development of native fauna. Ecotoxicological quality of water bodies from agricultural sites was evaluated by means of standardized laboratory bioassays with embryos and larvae of the native amphibian Rhinella arenarum. The organisms were acutely and chronically exposed to surface water samples from streams of Arrecifes (A), Pergamino (P) and Salto (S) districts that represent the most important agricultural core from the region. Lethal, sublethal and genotoxic effects were assessed. Water sample from (A) caused chronic toxicity (LC50:45.35%) in embryos, followed by (S) and the water sample from (P) was not toxic. In larvae, an inversion of the toxicity pattern was found. Thus, the 504 h-LC50s were 28.12%, 39% and 61% for (S), (P) and (A), respectively. A stage-dependent sensitivity was registered, being larvae more affected than embryos. Significant genotoxic effects, estimated by micronucleus test were observed in the larvae exposed to water samples from all sites. The present study warns about environmental degradation of surface waters next to agricultural areas of Buenos Aires Province. This fact jeopardizes R. arenarum populations in this area.Fil: Peluso, Julieta. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Aronzon, Carolina Mariel. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Perez Coll, Cristina Silvia. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; Argentin