Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23.266
Filtrar
1.
Environ Monit Assess ; 193(3): 132, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33590385

RESUMEN

The sources of endocrine-disrupting persistent organochlorine compounds (OC) are environmental pollutants. Contaminated food is a direct result of environmental pollution, and fish are considered as the main source of OC in the human diet. This study aimed to analyze the contamination of imported fish fillets with organochlorine pesticides (OCPs) and polychlorinated biphenyl (PCB) congeners in the context of potential health risks of consumers in Poland in the light of the new tolerable weekly intake (TWI) values. The tested compounds in fish products were determined by liquid-liquid extraction and gas chromatography mass spectrometry (GS-MS) method. Despite the detection of almost all pesticides analyzed in the fish fillets tested, the risk factor (hazard quotient) was significantly lower than 1.0, ranging from 0.003 to 0.013. Considering the previous recommended TWI value (14 pg-TEQ/kg bw/week), the estimated weekly intake was lower at 43-53% of TWI. However, according to the new TWI values set by the EFSA in 2018, the estimated weekly intake was about three times higher than the TWI. This raises concerns regarding threats to consumer health.


Asunto(s)
Contaminantes Ambientales , Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Animales , Asia , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Productos Pesqueros/análisis , Contaminación de Alimentos/análisis , Humanos , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Polonia , Bifenilos Policlorados/análisis , Medición de Riesgo , Xenobióticos
2.
Artículo en Chino | MEDLINE | ID: mdl-33535335

RESUMEN

Objective: To explore the self-conscious health status and related influencing factors of greenhouse agricultural workers in Beijing suburb, so as to provide scientific basis for developing strategies to improve and promote the occupational health conditions of those workers. Methods: According to the production characteristics and scale of the main agricultural districts or counties in the suburb of Beijing, 182 agricultural production personnel were randomly selected to investigate the general situation, occupational situation and self-conscious health status during June 2018 to December 2019. The relevant factors which may affect the self-conscious health conditions were also analyzed by statistical methods. Results: The detection or reported rate of self-conscious health problems was 51.6% (94/182) , among which 29.1% (53/182) workers reported musculoskeletal disorder diseases and 21.4% (39/182) workers reported nervous system diseases. And the self-conscious health status of greenhouse agricultural workers were statistically different in household registration, gender, marital status, working years, mixing or spraying pesticides, smoking or eating in the greenhouse (P<0.05) . Moreover, gender, mixing or spraying pesticide, eating and smoking behavior in the workplace all had an impact on the risk of self-conscious health status of greenhouse agricultural workers (P< 0.05) . Specifically, male is the protective factor to reduce the occurrence of self-conscious symptoms of greenhouse agricultural workers (OR=0.447, 95%CI: 0.234~0.852) , while mixing or spraying pesticides and smoking or eating behaviors in the workplace are the risk factors (OR=1.055, 2.524; 95%CI: 0.503~2.210, 1.107~5.755) . Conclusion: Reducing pesticide use from the source thus minimize related exposure opportunities, strengthening occupational health education thus foster good hygienic habits and improve individual protection consciousness are of great significance for the health protection of greenhouse agricultural workers in Beijing suburb.


Asunto(s)
Enfermedades de los Trabajadores Agrícolas , Exposición Profesional , Plaguicidas , Agricultura , Beijing , Agricultores , Estado de Salud , Humanos , Masculino , Exposición Profesional/análisis
3.
Environ Pollut ; 271: 116359, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33535363

RESUMEN

Organochlorine pesticides (OCPs) have been produced for almost a century and some of them are still used, even after they have been proved to be toxic, persistent, bioaccumulative and prone to long-range transport. Brazil has used and produced pesticides in industrial scales for both agricultural and public health purposes. Urban and industrial regions are of special concern due to their high population density and their increased exposure to chemical pollution, many times enhanced by chemical production, application or irregular dumping. Therefore, we aimed to investigate the occurrence of OCPs in outdoor air of urban sites from two major regions of southeast Brazil. Some of these sites have been affected by OCP production and their irregular dumping. Deterministic and probabilistic inhalation cancer risk (CR) assessments were conducted for the human populations exposed to OCPs in ambient air. Ambient air was mainly affected by Æ©-HCH (median = 340 pg m-3) and Æ©-DDT (median = 233 pg m-3), the only two OCPs registered for domissanitary purposes in Brazil. OCP concentrations tended to be higher in summer than in winter. Dumping sites resulted in the highest OCP atmospheric concentrations and, thus, in the highest CR estimations. Despite of all limitations, probabilistic simulations suggested that people living in the studied regions are exposed to an increased risk of hepatic cancer. Infants and toddlers (0 < 2 y) were exposed to the highest inhalation CRs compared to other age groups. Other exposure pathways (such as ingestion and dermic uptake) are needed for a more comprehensive risk assessment. Moreover, this study also highlights the need to review the human exposure to OCPs through inhalation and their respective CR in other impacted areas worldwide, especially where high levels of OCPs are still being measured.


Asunto(s)
Hidrocarburos Clorados , Neoplasias , Plaguicidas , Brasil , Preescolar , Monitoreo del Ambiente , Humanos , Hidrocarburos Clorados/análisis , Plaguicidas/análisis
4.
Pestic Biochem Physiol ; 172: 104764, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33518051

RESUMEN

Potato (Solanum tuberosum L.) is one of the most common crops in the world, and it is very susceptible to a wide range of pests such as insects and fungi. The use of pesticides often results in the suppression of seed germination and plant growth, in particular, due to their effect on the respiratory chain of mitochondria. There are numerous studies of the effect of pesticides on animal mitochondria, but their interference with the electron transport in plant mitochondria is not well documented. We present the data showing that a number of pesticides inhibit electron flow, and other pesticides uncouple the respiratory chain. Among the studied pesticides engaging the alternative pathways of electron transport, dithianon led to an increase in the rate of H2O2 production but did not cause a strong increase in the amount of mtDNA damage as compared to other pesticides. In general, the main negative effect of the studied pesticides is manifested in a decrease of membrane potential with the maintenance of the rate of oxygen consumption and a low rate of H2O2 production. The mtDNA damage is caused mainly by pesticides belonging to the pyrethroid class and remains minor as compared to its damage in animals. Our data indicate that the respiratory chain of plant mitochondria is more resistant to pesticides as compared to animal mitochondria due to the presence of the alternative pathways of electron transport.


Asunto(s)
Plaguicidas , Solanum tuberosum , Animales , ADN Mitocondrial , Peróxido de Hidrógeno , Mitocondrias , Plaguicidas/toxicidad
5.
Forensic Sci Rev ; 33(1): 67-78, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33518515

RESUMEN

Pesticides are chemical or biological agents used to repel or kill pests. Pesticides are potent and lethal toxic substances that are also being infamously used for homicidal purposes due to their easy availability and rapid action. In this review, we look at 21 articles related to homicidal pesticide poisoning in the literature with an emphasis on fatal doses, routes of administration, and profiles of victims and perpetrators. Organophosphates and rodenticides were the most commonly used classes of pesticides, and ingestion was the most common route of administration; however, other modes of administration, such as through intraperitoneal injection, were also reported. Interestingly, we have noticed that victims involved in homicidal poisoning were mostly in close relationships with perpetrators. Most perpetrators were either spouses or other immediate family members. Abiding by the regulations that govern the production, sale, and use of pesticides and proper documentation of the related trail can help control the prevalence of homicidal pesticide poisoning. Recognition of the distinct morbid anatomy of the poisoning cases, alongside a high index of suspicion in cases that fit the profile, is essential for forensic analysis.


Asunto(s)
Plaguicidas/envenenamiento , Rodenticidas/envenenamiento , Medicina Legal , Humanos , Organofosfatos
6.
Environ Pollut ; 272: 116414, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33445151

RESUMEN

Organophosphorus pesticides such as chlorpyrifos are often used in agriculture due to their broad spectrum of action. However, this insecticide and acaricide is considered highly toxic to the environment and can cause toxicity in nontarget insects such as bees. In addition to adult individuals, immature can also be exposed to residues of this insecticide by larval food. Thus, we investigated the effects of chlorpyrifos concentrations on the larval development of stingless bee Scaptotrigona bipunctata workers reared in vitro. We evaluated four different biomarkers: a) survival, b) development time, c) body mass and d) morphological characteristics (head width, intertegular distance, wing area and proportion of deformed bees). The exposure of the larvae to different doses of chlorpyrifos significantly reduced survival probability but did not cause changes in the development time. Regarding morphometric analysis, bees exposed to chlorpyrifos showed a reduction in body mass and size, and 28% of the emerged adults showed a reduction in wing area and deformations. Therefore, this work shows that S. bipunctata larvae exposed to the sublethal effects of chlorpyrifos are likely to have reduced chances of survival. However, if they emerge, they will be lighter, smaller and less able than equivalent but not exposed workers. These impaired attributes have the potential to compromise the future workforce in colonies exposed to this pesticide.


Asunto(s)
Cloropirifos , Insecticidas , Plaguicidas , Agricultura , Animales , Abejas , Cloropirifos/toxicidad , Insecticidas/toxicidad , Larva , Plaguicidas/toxicidad
7.
Environ Sci Pollut Res Int ; 28(9): 11697-11707, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33438128

RESUMEN

In this study, three different passive sampling receiving phases were evaluated, with a main focus on the comparability of established styrene-divinylbenzene reversed phase sulfonated (SDB-RPS) sampling phase from Empore™ (E-RPS) and novel AttractSPE™ (A-RPS). Furthermore, AttractSPE™ hydrophilic-lipophilic balance (HLB) disks were tested. To support sampling phase selection for ongoing monitoring needs, it is important to have information on the characteristics of alternative phases. Three sets of passive samplers (days 1-7, days 8-14, and days 1-14) were exposed to a continuously exchanged mixture of creek and rainwater in a stream channel system under controlled conditions. The system was spiked with nine pesticides in two peak scenarios, with log KOW values ranging from approx. - 1 to 5. Three analytes were continuously spiked at a low concentration. All three sampling phases turned out to be suitable for the chosen analytes, and, in general, uptake rates were similar for all three materials, particularly for SDB-RPS phases. Exceptions concerned bentazon, where E-RPS sampled less than 20% compared with the other phases, and nicosulfuron, where HLB sampled noticeably more than both SDB-RPS phases. All three phases will work for environmental monitoring. They are very similar, but differences indicate one cannot just use literature calibration data and transfer these from one SDB phase to another, though for most compounds, it may work fine.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Interacciones Hidrofóbicas e Hidrofílicas , Plaguicidas/análisis , Ríos , Contaminantes Químicos del Agua/análisis
8.
Environ Sci Pollut Res Int ; 28(8): 10283-10291, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33447982

RESUMEN

Among the various species of vegetation, conifers play an important role as a biomonitor of air pollution. The current study presents the determination of pesticides and polycyclic aromatic hydrocarbons in 15 conifer samples collected in August 2018 (summer season) from different regions in north Lebanon (Tripoli, Koura, Bcharre, and Akkar). Pollutants were extracted based on QuEChERS-SPME followed by liquid and gas chromatography-tandem mass spectrometry. Results showed that the samples collected from Bcharre region had the lowest concentration in both pesticides and polycyclic aromatic hydrocarbons with a total concentration of 50 and 66 ng g-1, while the samples collected from the regions widely known by their agriculture (Akkar, Tripoli, and Koura areas) were the most polluted with concentrations of 231 and 422 ng g-1, 192 and 370 ng g-1, and 127 and 98 ng g-1 for pesticides and polycyclic aromatic hydrocarbons respectively. This study revealed that conifers are suggested to be efficient biomonitors of contamination levels in the air.


Asunto(s)
Plaguicidas , Pinus , Hidrocarburos Policíclicos Aromáticos , Monitoreo del Ambiente , Cromatografía de Gases y Espectrometría de Masas , Líbano , Plaguicidas/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
9.
Bull Environ Contam Toxicol ; 106(2): 243-249, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33452610

RESUMEN

The concept of the Nitrogen (N) cycle has been modified over the years based on certain new pathways, including comammox, anammox, and DNRA (dissimilatory nitrate reduction to ammonium). Comammox, nitrification, anammox, denitrification, DNRA, and nitrogen fixation pathways play key roles in the N cycle in paddy soils. Pesticides and chemical fertilizers' effects on the N cycle in paddy soils together with the possible manifestation of these newly discovery pathways are the focus of this review. Both chemical fertilizers and pesticides' overuse affect nitrifying archaea/bacteria and denitrifying and anammox bacteria, while heavy metals affect the nitrification rates in paddy soils. To add extra value to this study, we quantified the comammox amoA single copy gene from the Nitrospira strain 'Nitrospira inopinata'. This review will help researchers access the latest information on the N cycle, particularly in the light of the most recent discoveries.


Asunto(s)
Microbiota , Plaguicidas , Bangladesh , Desnitrificación , Fertilizantes/análisis , Nitrificación , Nitrógeno , Ciclo del Nitrógeno , Oxidación-Reducción , Suelo
10.
Ecotoxicol Environ Saf ; 211: 111869, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33450537

RESUMEN

Solitary bees are among the most important pollinators worldwide however population declines especially in croplands has been noticed. The novel pesticide sulfoxaflor is a competitive modulator of nicotinic acetylcholine receptors (nAChR) in insects. While there is evidence of a negative impact of neonicotinoids on bees of several social organization levels, our overall knowledge on the impact of sulfoxaflor on bees is poor. Here we present for the first time a study showing effects of field realistic doses of sulfoxaflor on solitary bees. Bees submitted to long term exposure of field realistic doses of sulfoxaflor (5 µg dm-3, 10 µg dm-3, 50 µg dm-3) and control were observed regarding their survival rate. Moreover, we recorded metrics related to flower visitation and flight performance. We discover that the highest field realistic dose is lethal to Osmia bicornis along five days of exposure. The effect of sulfoxaflor reduces the outcome of foraging, important features for fruit and seed production of cross-pollinated plant species. Bees exposed to pesticide visited flowers mostly walking rather than flying. Flight performance was also impaired by the pesticide.


Asunto(s)
Abejas/fisiología , Insecticidas/toxicidad , Animales , Conducta Alimentaria/efectos de los fármacos , Flores/efectos de los fármacos , Neonicotinoides/toxicidad , Plaguicidas/toxicidad , Polinización/efectos de los fármacos , Piridinas , Compuestos de Azufre , Tasa de Supervivencia
11.
Ecotoxicol Environ Saf ; 208: 111622, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396142

RESUMEN

The continuous growth in global population since the beginning of the 20th century result in the necessity of food and energy provision favoring the intensive use of agricultural products such as pesticides. Although pesticides are important to prevent losses in the conventional chemically based agriculture, they frequently present side effects, which goes against agricultural production. The use of pesticides cause direct and indirect effects to soil organisms unbalancing essential soil processes (e.g. primary production, organic matter decomposition, nutrient cycling). Under tropical conditions, very little is known regarding the effects of pesticides to terrestrial organisms. Hence, the aim of the present study was to assess the ecotoxicological effects of the herbicide DMA® 806 BR (active ingredient: 2,4-D) and the insecticide Regent® 800 WG (active ingredient: fipronil), on terrestrial plant species (the dicot Raphanus sativus var. acanthioformis and the monocot Allium cepa), and soil invertebrates (the collembolan Folsomia candida and the enchytraeid Enchytraeus crypticus), using natural (NS) and artificial soils (TAS). For both pesticides, negative effects on non-target species were observed at concentrations lower than the doses recommended to prevent pests in sugarcane fields. For both soils, the dicot species was the most affected by the herbicide (R. sativus > A. cepa > F. candida > E. crypticus) and the collembolan species was the most affected by the insecticide (F. candida > E. crypticus = R. sativus = A. cepa). Although the order of the organisms' sensitivity for both pesticides was the same in both soils, results showed that the extent of the effects was soil dependent. Considering the ecologically relevant concentrations tested, and their severe effects to non-target organisms, it may be concluded that the use of fipronil and 2,4-D under recommended conditions may pose a risk to the terrestrial environment.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético/toxicidad , Plaguicidas/toxicidad , Pirazoles/toxicidad , Saccharum/fisiología , Contaminantes del Suelo/análisis , Agricultura , Animales , Artrópodos/efectos de los fármacos , Artrópodos/fisiología , Ecotoxicología , Insecticidas/toxicidad , Oligoquetos/efectos de los fármacos , Oligoquetos/fisiología , Suelo/química
12.
Nat Commun ; 12(1): 132, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33420104

RESUMEN

The use of pesticides to reduce mosquito vector populations is a cornerstone of global malaria control efforts, but the biological impact of most pesticides on human populations, including pregnant women and infants, is not known. Some pesticides, including carbamates, have been shown to perturb the human immune system. We measure the systemic absorption and immunologic effects of bendiocarb, a commonly used carbamate pesticide, following household spraying in a cohort of pregnant Ugandan women and their infants. We find that bendiocarb is present at high levels in maternal, umbilical cord, and infant plasma of individuals exposed during pregnancy, indicating that it is systemically absorbed and trans-placentally transferred to the fetus. Moreover, bendiocarb exposure is associated with numerous changes in fetal immune cell homeostasis and function, including a dose-dependent decrease in regulatory CD4 T cells, increased cytokine production, and inhibition of antigen-driven proliferation. Additionally, prenatal bendiocarb exposure is associated with higher post-vaccination measles titers at one year of age, suggesting that its impact on functional immunity may persist for many months after birth. These data indicate that in utero bendiocarb exposure has multiple previously unrecognized biological effects on the fetal immune system.


Asunto(s)
Contaminantes Ambientales/efectos adversos , Feto/inmunología , Exposición Materna/efectos adversos , Sarampión/sangre , Plaguicidas/efectos adversos , Adulto , Anticuerpos Antivirales/sangre , Preescolar , Ensayos Clínicos Fase III como Asunto , Femenino , Sangre Fetal/química , Estudios de Seguimiento , Humanos , Sistema Inmunológico/efectos de los fármacos , Inmunogenicidad Vacunal , Inmunoglobulina G/sangre , Lactante , Recién Nacido , Malaria/prevención & control , Intercambio Materno-Fetal/inmunología , Sarampión/inmunología , Sarampión/prevención & control , Vacuna Antisarampión/administración & dosificación , Vacuna Antisarampión/inmunología , Control de Mosquitos/métodos , Plaguicidas/análisis , Fenilcarbamatos/efectos adversos , Fenilcarbamatos/análisis , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto
13.
Ecotoxicol Environ Saf ; 208: 111714, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396045

RESUMEN

Studies on the effects of unintentional intake of pyrethroid pesticides that are akin to actual human exposure settings are very rare. Such an exposure is primarily by consuming the food products as routine diet that contain residual levels of pyrethroids. In this study, rats were orally administered for 15 months with a mixture of pyrethroids at a dose that is one-fifth (high dose; HD) or one-twenty fifth (low dose; LD) of the residual levels commonly present in the average amount of rice and vegetables consumed by Indian population. Lipid profile, kidney and liver function were assessed. Lipid peroxidation, nitric oxide, antioxidant enzyme activities and histopathological changes were analyzed in the liver, lung, kidney, pancreas, testes, caput, cauda and prostate. The effect on the male reproductive system as a function of sperm count, enzyme activity of 3ß-HSD and 17ß-HSD and the expression profile of genes involved in spermatogenesis, steroidogenesis, genetic reprogramming and apoptosis of male gametes were evaluated. Significant increase in the relative organ weight, perturbations in the activities of antioxidant enzymes, lipid profile and liver function were observed in both LD and HD groups. Damage to the anatomical architecture was evident in all the tissues due to pyrethroid toxicity. Exposure to LD and HD of pyrethroid mixture resulted in decreased sperm count, activities of 3ß-HSD and 17ß-HSD, impaired capacitation and acrosome reaction and perturbations in the expression of genes that govern male gamete production. Results of our study indicate that exposure to pyrethroids for longer durations even at doses that are far below the residual levels present in the food consumed will result in severe damage to general physiological processes as well as reproductive function.


Asunto(s)
Exposición Dietética/efectos adversos , Plaguicidas/toxicidad , Piretrinas/toxicidad , Animales , Antioxidantes/metabolismo , Fertilización/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Tamaño de los Órganos/efectos de los fármacos , Residuos de Plaguicidas/toxicidad , Ratas , Espermatogénesis/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Espermatozoides/patología , Testículo/efectos de los fármacos , Testículo/metabolismo , Testículo/patología
14.
Ambio ; 50(3): 539-543, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33471250

RESUMEN

Reflections about three influential environmental contaminants papers published in Ambio are presented. The PCB Story by Jensen in (1972) had a very important influence on environmental chemistry. This is captured by way of comments and personal anecdotes. Wania's and MacKay's (1993) paper highlights the physical chemistry underlying transport of PCBs and organochlorine pesticides from temperate zone ecosystems to Polar Regions. Their paper exemplifies how principles of chemistry and environmental processes informed understanding the biogeochemical cycles of chemicals of environmental concern (CEC). Mergler et al.'s (2007) paper reviews knowledge of methyl mercury exposure and impacts in humans and served as an example of how to approach exposure and human health concerns for all CECs. All great progress. Then, the question: "How we missed for two decades the importance of plastics in the environment identified in a paper published the same year as The PCB Story? Are we missing yet another important environmental contaminant now?


Asunto(s)
Plaguicidas , Bifenilos Policlorados , Aniversarios y Eventos Especiales , Ecosistema , Monitoreo del Ambiente , Humanos , Plaguicidas/análisis , Bifenilos Policlorados/análisis
17.
Chemosphere ; 268: 129488, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33485672

RESUMEN

Organophosphorus pesticides (OPs) interfere with the activity of acetylcholinesterase (AChE), a vital enzyme that regulates the functioning of the nervous system, resulting in acetylcholine (Ach) accumulation at the synapses and myoneural junctions. It remains unknown whether the commonly used OPs in South India also interfere with the AChE activity and their toxicokinetics in humans remains poorly understood. We collected peripheral blood samples from OP-associated suicide cases (hospitalised) and analysed the pesticide concentration and AChE activity, and the toxicokinetics of six commonly used pesticides. LC-MS/MS was used for the estimation of pesticide concentration. Based on a comparison of six pesticide kinetic profiles and toxicokinetic parameters, we concluded that chlorpyrifos ingestion resulted in the highest concentration of chlopyrifos among the identified pesticides, followed by acephate, triazophos, propanil, while dimethoate exhibited the lowest concentration. Based on a time-course analysis, we observed a faster elimination phase for monocrotophos and dimethoate. We observed that there was a significant decrease in the mean concentration of monocrotophos (64 ng/mL) (P = 0.015), while the mean value of AChE (1.08 unit/mL) increased over time. While monocrotophos and dimethoate elimination phases were remarkable in human subjects, the other pesticides did notdemonstrate similar elimination phases owing to their low rate of metabolism and high stability.


Asunto(s)
Plaguicidas , Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/toxicidad , Cromatografía Liquida , Humanos , India , Compuestos Organofosforados , Plaguicidas/toxicidad , Espectrometría de Masas en Tándem , Toxicocinética
18.
J Chromatogr A ; 1638: 461856, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33485031

RESUMEN

Plant parasites and soilborne pathogens directly reduce the overall yield of crops, vegetables, and fruits, negatively impacting the market demand for these products and their net profitability. While preplant soil fumigation helps maintain the consistent production quality of high-value cash crops, most soil fumigants are toxic to off-target species, including humans. Dimethyl disulfide (DMDS) has recently been introduced as a relatively low toxicity soil fumigant. Although DMDS exhibits low toxicity compared to other soil fumigants, it is volatile and exposure can cause eye, nasal, and upper respiratory tract irritation, skin irritation, nausea, dizziness, headache, and fatigue. While there is one analysis method available for DMDS from biological matrices, it has significant disadvantages. Hence, in this study, a dynamic headspace gas chromatography-mass spectroscopy (DHS-GC-MS) method was developed for the analysis of DMDS in swine whole blood. This method is highly sensitive and requires only three steps: 1) acid denaturation, 2) addition of internal standard, and 3) DHS-GC-MS analysis. The method produced a wide linear range from 0.1 - 200 µM with an excellent limit of detection of 30 nM. Intra- and interassay accuracy (100±14% and 100±11%, respectively) and precision (<5% and <6% relative standard deviation, respectively) were also excellent. The method worked well to quantify the DMDS levels in the blood of dimethyl trisulfide (DMTS)-treated swine (i.e., DMDS is a byproduct of DMTS treatment) with no interfering substances at or around the retention time of DMDS (i.e., 2.7 min). This simple, rapid, and extremely sensitive method can be used for the quantification of DMDS levels in blood to verify exposure to DMDS or to monitor levels of DMDS following DMTS treatment (e.g., for cyanide poisoning).


Asunto(s)
Disulfuros/sangre , Cromatografía de Gases y Espectrometría de Masas , Contaminantes del Suelo/sangre , Porcinos , Animales , Fumigación , Plaguicidas/sangre , Sulfuros/sangre
19.
J Environ Manage ; 281: 111874, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33385909

RESUMEN

Surface-water irrigation is one of the most important irrigation methods in areas with abundant surface water. Although this method of irrigation is both economical and convenient, many contaminants are also introduced into the soil-water systems such as organophosphorus pesticides (OPPs). To study the influence of surface-water irrigation on the distribution of OPPs in soil-water systems, 42 water samples (38 groundwater and four surface water) and 85 soil samples (78 profile soil samples and seven topsoil samples) were taken from Shahu in the Jianghan Plain, China. Shahu is a typical Chinese surface-water irrigation district. During sampling, three types of areas were considered: surface-water irrigated areas, groundwater-irrigated areas away from rivers, and non-irrigated areas adjacent to rivers. The results showed that the concentrations of OPPs in the groundwater and soil in the surface-water irrigated farmland were higher than those in groundwater-irrigated farmland. The groundwater flow field and surface-water irrigation were responsible for the OPPs. Thus, it is clear that the surface-water irrigation had a strong influence on the distribution of OPPs in soil-water systems. Principal component analysis for OPPs content in groundwater showed that the key influencing factors on the distribution of OPPs in groundwater were the groundwater flow field and current pesticide use.


Asunto(s)
Agua Subterránea , Plaguicidas , Contaminantes Químicos del Agua , Riego Agrícola , China , Monitoreo del Ambiente , Plaguicidas/análisis , Suelo , Agua , Contaminantes Químicos del Agua/análisis
20.
J Environ Manage ; 282: 111949, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33445138

RESUMEN

Invasive species are a prominent feature of global change. Aside from their direct impacts on biodiversity and ecosystem functioning, invasive crop pests routinely trigger environmentally-disruptive actions e.g., unguided applications of synthetic pesticides. Since 2016, the polyphagous fall armyworm (FAW, Spodoptera frugiperda J.E. Smith) has rapidly spread across Africa and Asia, impacting millions of hectares of agricultural crops. Upon its invasion of Yunnan (China) in late 2018, S. frugiperda attained outbreak population levels and inflicted important feeding damage in smallholder-managed maize crops. In this study, we show how local maize growers rely primarily on pesticides for FAW management and employ these products at 3-fold higher application frequencies as compared to 2018. Local reliance upon high-risk compounds (i.e., pyrethroids, organophosphates) decreased over time, with a respective 100% and 62% farmers using these compounds in 2018 versus 27% and 5% in 2020. Conversely, 71% and 95% farmers used new, selective compounds such as emamectin benzoate and chlorfenapyr by 2020. The full cost of pesticide-based crop protection increased from US $81 per hectare and season in 2018 to $276 in 2020. In farmer-managed fields, FAW infestation levels averaged 8.3 larvae per 100 plants and thus remained below economic injury levels (EILs) as established in other countries. Farmers' use of two or more pesticide sprays per season likely was not economically justified. Our work demonstrates how the FAW invasion has altered pest management regimes in Yunnan's maize crop, deepening farmers' pesticide dependency, and potentially exacerbating its burden on household budgets. Sustainable pest management schemes urgently need to be devised for smallholder maize systems in China and across the FAW invaded range.


Asunto(s)
Agricultores , Plaguicidas , África , Animales , Asia , China , Ecosistema , Gastos en Salud , Humanos , Spodoptera
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA