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Neurotoxicity and reproductive biomarkers in pesticide sprayers
S224
Abstracts / Toxicology Letters 259S (2016) S73–S247
PP23.21 Molecular, biochemical and behavioral effects of the pesticide chlorothalonil in the zebrafish (D. rerio)
PP23.22 Neurotoxicity and reproductive biomarkers in pesticide sprayers
A.B. M. C.J. K.R. Munkittrick 2,4 , P. Almazan 1 , H. Mejia-Ruiz 5 , A. Garcia-Gasca 1 , S. Soto 1
M. Solís-Heredia 1 , G.A. Álvarez-Puentes 2 , A.B. Benitez-Trinidad 3 , J.F. Herrera-Moreno 3 , I.M. Medina-Díaz 3 , Y.Y. Bernal-Hernández 3 , B.S. Barrón-Vivanco 3 , B. Quintanilla-Vega 1 , A.E. Rojas-García 3
1
1
Sánchez-Garayzar 1 ,
Betancourt 1 ,
Martyniuk 2,3 ,
CIAD, Unit for Aquaculture and Environmental Management, Mazatlán, Sinaloa, Mexico 2 Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, NB, Canada 3 Center for Environmental and Human Toxicology, Department of Physiological Sciences, University of Florida, Gainesville, USA 4 COSIA, Calgary, Canada 5 CIBNOR, La Paz, BCS, Mexico Chlorothalonil is a broad-spectrum pesticide, mainly used in agricultural crops, anti-fouling paints and pesticides for domestic use. As an extensively used fungicide, it is widely spread in the aquatic environment. However, despite its high usage, there are relatively few studies on its effects on non-target aquatic organisms. Moreover, its mode of action is not well understood. In this study, the effects of chlorothalonil on adult male zebrafish, Danio rerio, were evaluated in order to better understand its mode of action in vertebrate aquatic organisms. Exposures to two experimental concentrations of chlorothalonil were conducted: 0.007 mg/L (low, environmentally-relevant) and 0.035 mg/L (high, sublethal). The effects of chlorothalonil on zebrafish were assessed at different levels of biological organization: gene expression (microarray and real-time PCR), biological and physiological indexes, biochemical (e.g. glucose and cortisol), as well as behavioral observations. Molecular analysis revealed that exposure to chlorothalonil affected genes related to cell division, gluconeogenesis, and DNA damage, as well as those related to reproduction, immune system and detoxification. A significant increase in cortisol in organisms exposed to both concentrations during the first 12 h was observed, reaching levels comparable to control animals at 96 h, while glucose levels also showed a tendency to increase in exposed fish compared to control. Taken together, these data indicate that chlorothalonil may produce an energy imbalance, possibly by disrupting cellular respiration, inducing oxidative stress and hypoxia. The foregoing is consistent with morphological and behavioral alterations, as the decrease in the hepatosomatic index and alteration in locomotive activities, respectively. Additionally, the results also suggest that chlorothalonil may be an estrogenic compound, given that genes related to reproductive processes, such as vitellogenin and zona pellucida, were induced in the liver following exposure. The present study allows an integrated approach to the mode of action of chlorothalonil in aquatic vertebrates. Financial support: CONACYT, National Network of Pesticides, Canada Research Chair funding and Natural Sciences and Engineering Research Council of Canada (NSERC). http://dx.doi.org/10.1016/j.toxlet.2016.07.538
Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, Mexico 2 Laboratorio de Contaminación y Toxicología Ambiental, Universidad Autónoma de Nayarit, Nayarit, Mexico 3 Posgrado en Ciencias Biológico Agropecuarias, Universidad Autónoma de Nayarit, Nayarit, Mexico Introduction: The state of Nayarit, Mexico, is one of the most important agricultural producers in the country, a reason for which the use of pesticides is extensive. In addition, the use of these compounds as a control for the vectors of diseases has increased during the last few years, intensifying the amount of pesticides used. Although there are several studies conducted to evaluate the acute effects caused by the exposure to pesticides, there is little information regarding their effects on reproduction. Objective: To evaluate the neurotoxicity and reproductive biomarkers in pesticide sprayers. Materials and methods: The study was carried out in 208 workers engaged in urban fumigation in the state of Nayarit, Mexico. Neurotoxicity was evaluated by measuring the activity of the enzymes acetylcholinesterase and butyrylcholinesterase by colorimetric methods, as well by a structured questionnaire. Sperm quality was determined according to the World Health Organization (WHO) guidelines. DNA integrity of sperm cells was determined by the Sperm Chromatin Structure Assay (SCSA, % of DNA Fragmentation Index [DFI]). Results: A decrease in butyrylcholinesterase activity was observed in the study participants with the highest exposure. The most referred symptom was cephalea, followed by skin irritation and weakness. The sperm-quality results revealed the presence of immature cells as the most abnormal parameter observed in the population, followed by the liquefaction time and sperm viability. An average of 26.13% was obtained for the DFI, with 52.5% of participants exhibiting values higher than the normal value (≤25%). Conclusions: The results obtained suggest that pesticide exposure exerts an effect on the nervous and reproductive systems. Financial support: This study was supported by CONACyTMéxico (grant #233803). The authors express their acknowledgement to the Pesticide Toxicology Network (Conacyt-253789/ 271775). http://dx.doi.org/10.1016/j.toxlet.2016.07.539
Abstracts / Toxicology Letters 259S (2016) S73–S247
PP23.21 Molecular, biochemical and behavioral effects of the pesticide chlorothalonil in the zebrafish (D. rerio)
PP23.22 Neurotoxicity and reproductive biomarkers in pesticide sprayers
A.B. M. C.J. K.R. Munkittrick 2,4 , P. Almazan 1 , H. Mejia-Ruiz 5 , A. Garcia-Gasca 1 , S. Soto 1
M. Solís-Heredia 1 , G.A. Álvarez-Puentes 2 , A.B. Benitez-Trinidad 3 , J.F. Herrera-Moreno 3 , I.M. Medina-Díaz 3 , Y.Y. Bernal-Hernández 3 , B.S. Barrón-Vivanco 3 , B. Quintanilla-Vega 1 , A.E. Rojas-García 3
1
1
Sánchez-Garayzar 1 ,
Betancourt 1 ,
Martyniuk 2,3 ,
CIAD, Unit for Aquaculture and Environmental Management, Mazatlán, Sinaloa, Mexico 2 Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, NB, Canada 3 Center for Environmental and Human Toxicology, Department of Physiological Sciences, University of Florida, Gainesville, USA 4 COSIA, Calgary, Canada 5 CIBNOR, La Paz, BCS, Mexico Chlorothalonil is a broad-spectrum pesticide, mainly used in agricultural crops, anti-fouling paints and pesticides for domestic use. As an extensively used fungicide, it is widely spread in the aquatic environment. However, despite its high usage, there are relatively few studies on its effects on non-target aquatic organisms. Moreover, its mode of action is not well understood. In this study, the effects of chlorothalonil on adult male zebrafish, Danio rerio, were evaluated in order to better understand its mode of action in vertebrate aquatic organisms. Exposures to two experimental concentrations of chlorothalonil were conducted: 0.007 mg/L (low, environmentally-relevant) and 0.035 mg/L (high, sublethal). The effects of chlorothalonil on zebrafish were assessed at different levels of biological organization: gene expression (microarray and real-time PCR), biological and physiological indexes, biochemical (e.g. glucose and cortisol), as well as behavioral observations. Molecular analysis revealed that exposure to chlorothalonil affected genes related to cell division, gluconeogenesis, and DNA damage, as well as those related to reproduction, immune system and detoxification. A significant increase in cortisol in organisms exposed to both concentrations during the first 12 h was observed, reaching levels comparable to control animals at 96 h, while glucose levels also showed a tendency to increase in exposed fish compared to control. Taken together, these data indicate that chlorothalonil may produce an energy imbalance, possibly by disrupting cellular respiration, inducing oxidative stress and hypoxia. The foregoing is consistent with morphological and behavioral alterations, as the decrease in the hepatosomatic index and alteration in locomotive activities, respectively. Additionally, the results also suggest that chlorothalonil may be an estrogenic compound, given that genes related to reproductive processes, such as vitellogenin and zona pellucida, were induced in the liver following exposure. The present study allows an integrated approach to the mode of action of chlorothalonil in aquatic vertebrates. Financial support: CONACYT, National Network of Pesticides, Canada Research Chair funding and Natural Sciences and Engineering Research Council of Canada (NSERC). http://dx.doi.org/10.1016/j.toxlet.2016.07.538
Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, Mexico 2 Laboratorio de Contaminación y Toxicología Ambiental, Universidad Autónoma de Nayarit, Nayarit, Mexico 3 Posgrado en Ciencias Biológico Agropecuarias, Universidad Autónoma de Nayarit, Nayarit, Mexico Introduction: The state of Nayarit, Mexico, is one of the most important agricultural producers in the country, a reason for which the use of pesticides is extensive. In addition, the use of these compounds as a control for the vectors of diseases has increased during the last few years, intensifying the amount of pesticides used. Although there are several studies conducted to evaluate the acute effects caused by the exposure to pesticides, there is little information regarding their effects on reproduction. Objective: To evaluate the neurotoxicity and reproductive biomarkers in pesticide sprayers. Materials and methods: The study was carried out in 208 workers engaged in urban fumigation in the state of Nayarit, Mexico. Neurotoxicity was evaluated by measuring the activity of the enzymes acetylcholinesterase and butyrylcholinesterase by colorimetric methods, as well by a structured questionnaire. Sperm quality was determined according to the World Health Organization (WHO) guidelines. DNA integrity of sperm cells was determined by the Sperm Chromatin Structure Assay (SCSA, % of DNA Fragmentation Index [DFI]). Results: A decrease in butyrylcholinesterase activity was observed in the study participants with the highest exposure. The most referred symptom was cephalea, followed by skin irritation and weakness. The sperm-quality results revealed the presence of immature cells as the most abnormal parameter observed in the population, followed by the liquefaction time and sperm viability. An average of 26.13% was obtained for the DFI, with 52.5% of participants exhibiting values higher than the normal value (≤25%). Conclusions: The results obtained suggest that pesticide exposure exerts an effect on the nervous and reproductive systems. Financial support: This study was supported by CONACyTMéxico (grant #233803). The authors express their acknowledgement to the Pesticide Toxicology Network (Conacyt-253789/ 271775). http://dx.doi.org/10.1016/j.toxlet.2016.07.539