Effects Of Captan Research Articles

Effects of captan, mancozeb and azoxystrobin fungicides on motility, oxidative stress and fatty acid profiles in rainbow trout (Oncorhynchus mykiss) spermatozoa

An in vitro study using rainbow trout spermatozoa was designed to evaluate the toxic effects of different concentrations of captan (CPT), mancozeb (MCZ), and azoxystrobin (AZX) fungicides on motility parameters, lipid peroxidation, SOD activity, total antioxidant capacity (TAC), and DPPH inhibition. Moreover, changes in fatty acids profiles caused by the fungicides were determined for the first time. The results revealed that motility parameters, SOD activities, TAC values, and DPPH inhibitions decreased significantly while lipid peroxidation increased after ≥2 µg/L of CPT, ≥1 µg/L of MCZ, and ≥5 µg/L of AZX incubations for 2 h at 4 °C. Additionally, 10 µg/L CPT, 5 µg/L MCZ, and 200 µg/L AZX reduced motility to the 50 % level. Our results clearly demonstrated significant changes in the fatty acids profiles of spermatozoa exposed to these concentrations of the fungicides. The highest lipid peroxidation and the lowest monounsaturated and polyunsaturated saturated fatty acids (MUFA and PUFA, respectively) were detected in AZX. Even though the susceptibility of spermatozoa to oxidative damage is generally attributed to PUFA contents, the results of this study have represented that MUFA content could play a part in this tendency. Moreover, the lower concentration of MCZ reduced motility to the % 50 level while it deteriorated the fatty acids profile less than did AZX. Overall, the present study demonstrated that the detrimental effects of the fungicides on mitochondrial respiration and related enzymes have more priority than oxidative stress in terms of their toxicities on spermatozoa. It has also been suggested that fish spermatozoa are a good model for determining changes in the fatty acid profiles by fungicides, probably, by other pesticides and environmental contaminants as well.

Systematic Toxicological Analysis Revealing a Rare Case of Captan Ingestion

This article presents a case of suicide by intoxication with various pharmaceuticals, particularly anticonvulsants, combined with the fungicide captan. A cause of death could not be ascertained at autopsy. However, systematic toxicological analysis (STA) including a screening via solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for (semi) volatile organic compounds revealed results suggesting a possible cause of death. The effects of captan on the human organism, its metabolism, and distribution will be discussed. Macroscopically, the cause of death was unascertained. STA revealed clonazepam, citalopram, and its metabolites, lamotrigine, levetiracetam, lacosamide, clonazepam, captan, and its metabolite tetrahydrophthalimide (THPI). For the first time, it was detected in human viscera. A quantification of THPI was performed to obtain distribution in the organs. The significance of a complete STA must be emphasized. The presence of THPI would have been missed without previous detection of captan. Consequently, this fatality would not have been investigated satisfactorily.

Effects of Captan, a fungicide, on mammalian slow‐twitch muscle

The population exposure to pesticides is dramatically increasing in the last few decades because of the widespread uncontrolled use of pesticides especially in the developing countries. In our study, we examine the effect of 6 mg/kg of Captan, a fungicide, mixed with diet, on body weight, muscle mass, proteins content and contractile response of slow‐twitch skeletal muscles (soleus). As compared with controls placebo animals, 2 weeks of treatment induces a significant increasing in body weight (15%) and muscle mass (14%) which could be due in part to the increasing in soluble and Myofibrillar proteins content. Moreover, our results show that Captan treatment induces a decreasing by 15% in the expression of MHC I isoforms (Control: 88.7 ± 3.2 ; Captan: 75.3 ± 2.3) and an increasing in the expression of MHCII isoforms (Control: MHC IIa: 1.09 ±0.61; MHC IIb: 10.34±2.33; MHC IIx/d: 1.28±1.02; Captan: MHC IIa: 9.79±1.61; MHC IIb: 17.91±1.40; MHC IIx/d: 12.28±1.72; p<0.05; n= 10). Thus, this study shows that treatment by Captan mixed with diet can induce an effect in myofibrillar proteins of slow‐ twitch mammalian skeletal muscles by shifting in the expression of slow MHC type into fast MHC type.

The mutagenic effect of captan in bacteriophages T4D.

The mutagenic effect of captan in bacteriophages T4D.

A microcosm approach to assess the effects of fungicides on soil ecological processes and plant growth: comparisons of two soil types

The effects of three broad-spectrum fungicides, benomyl, captan and chlorothalonil, applied at recommended field application rates and 10 times these rates, on soil microbial activity and biomass (SIR), nitrogen dynamics, organic matter decomposition, and plant growth, were studied in microcosms containing two different types of soils. Soil type significantly affected all measurements except NH 4–N, DON and in situ NO 3–N availability measured on an anion-exchange membrane. The higher rate of all fungicide treatments had greater effects on soil microbial activity and nitrogen dynamics than the lower rates. Both concentrations of benomyl increased peak SIR rates and soil dehydrogenase activity (DHA). Captan and chlorothalonil decreased both peak SIR rates and DHA activity. Both application rates of benomyl and chlorothalonil did not affect concentrations of NH 4–N in either soil; however, the higher rate of captan increased NH 4–N concentrations significantly in both soils. Concentrations of NO 3–N were increased by the higher application rates of both benomyl and chlorothalonil, but decreased by the higher application rate of captan. Dissolved organic N concentrations were increased by the higher application rate of fungicides. All fungicide treatments except the higher rate of chlorothalonil, enhanced rates of net N mineralization and nitrification initially, but reduced the rates after 20 days. Captan, especially at the higher application rate, decreased in situ concentrations of NO 3–N significantly. The germination success of oat seeds was not influenced by any fungicide treatment in either type of soil. The lower application rate of benomyl stimulated oat growth significantly (0.05< P<0.10) in the silt loam soil, but the higher application rate of benomyl had the opposite effect. Neither benomyl nor chlorothalonil influenced rates of organic matter decomposition. The effects of captan on rates of organic matter decomposition depended on the soil type. The three fungicides differed in their effects on soil processes and plant growth in the two soil types. Compared to the relatively transient effects of benomyl and chlorothalonil, captan had a greater and longer-lasting overall influence on soil microbial activity and nitrogen dynamics.

Effects of the fungicide Captan on some functional groups of soil microflora

The effects of Captan at rates of 2.0, 3.5, 5.0 and 10.0 kg ha −1 on microbial function were studied in four agricultural soils under aerobic conditions. Parameters monitored included total culturable populations, numbers of aerobic N 2-fixing bacteria, denitrifying bacteria, nitrifying bacteria and nitrogenase activity. Total culturable fungal populations, nitrifying bacteria, aerobic N 2-fixing bacteria and nitrogenase activity were significantly decreased at dose rates of 2.0 to 10.0 kg ha −1. However, the presence of Captan enhanced denitrifying and total culturable bacteria, showing that some microbial groups can tolerate high doses of this fungicide.

Transgenic strains of the nematode C. elegans in biomonitoring and toxicology: Effects of captan and related compounds on the stress response

The fungicide, captan, induces a cellular stress response in the soil nematode Caenorhabditis elegans. Transgenic C. elegans, which produce β-galactosidase as a surrogate stress protein, reveal that captan-induced stress is localized mainly to muscle cells of the pharynx. The stress response is elicited by captan concentrations above 5 ppm and occurs within five hours of the initial exposure to the fungicide. Higher concentrations of captan, up to the solubility limit, increase the intensity of the response. Adult nematodes are significantly more sensitive to captan than are larvae. Captan also inhibits feeding in C. elegans, and nematodes exposed to captan rapidly cease muscular contractions in the pharynx. Stress induction and feeding inhibition are also caused by the related fungicides, captafol and folpet, but not by the parent compounds, phthalimide and tetrahydrophthalimide. The inhibition of feeding caused by compounds which elicit the cellular stress response may be an important survival mechanism for C. elegans.

The effects of captan and captafol on different bacterial strains and on c-mitosis in V79 Chinese hamster fibroblasts.

The mutagenic activity of captan and captafol was tested using Ames strains and strains showing an SOS response. Captafol was mutagenic in S. typhimurium strain TA102 (uvr+) and captan in strain TA104 (uvrB). Both captan and captafol elicit damages in DNA recognized by correndonuclease II, as shown by the repair test, and induced the SOS repair system in E. coli PQ37 (uvrA) strain. Only captafol induced the SOS system in PQ35 (uvr+). The lack of induction of beta-galactosidase at nonpermissive temperature in E. coli MD332 (dnaCs uvrA) strain showed that neither chemical was able to produce DNA breaks. In V79 Chinese hamster fibroblasts higher induction of c-mitosis by captafol than by captan (22% and 15% over the control, respectively) was accompanied by a higher decrease in nonprotein sulfhydryl groups, mainly GSH (41% and 77%, respectively). The content of protein sulfhydryl groups was decreased by either fungicide to a similar extent.

Growth Characteristics and Root Calcium Absorption of Watermelon Seedlings as Influenced by the Fungicides Captan and Thiram

The influence of two fungicides—captan and thiram—on growth and 45Ca absorption by roots of `Starbrite' watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] seedlings was investigated. Unilateral application of Ca+2 and Al in agar induced curvature in roots from untreated and pretreated seeds. In untreated seeds, PCMBS inhibited Ca+2- and Al-induced root curvature by 82% and 92%, respectively. In commercially pretreated seeds (captan + thiram), PCMBS inhibited Ca+2- but not Al-induced root curvature. Captan or thiram also inhibited Ca+2- or Al-induced root curvature, and the effects of captan and thiram on root curvature were additive. Serial concentration (0, 0.01, 0.1, 1, 10, or 100 mg·liter-1) tests indicated that captan inhibited 45Ca absorption the most at 100 mg·liter-1, whereas thiram inhibited 45Ca absorption the most at 0.01 mg·liter-1. The effects of captan and thiram on 45Ca absorption were statistically additive. Thiram seemed to influence Ca+2 uptake by affecting exofacial sulfhydryl groups (a mode of action similar to that of PCMBS). DTT reversed the inhibitory effect of thiram on 45Ca absorption by 34% but did not reverse the effect of captan. A field test showed that acidic soil (pH 4.55) reduced leaf number; leaf, stem, shoot, and whole-plant dry weights; and stem length of 15-day-old seedlings. Although there was no difference in root dry weights or root: shoot ratios of plants from pretreated and untreated seeds planted in soil at pH 6.26, planting commercially pretreated seeds in acidic soil produced plants with greater root dry weights and root: shoot dry weight ratios than those from untreated seeds. Seedlings showed a greater response to seed treatment in early growth stages. Captan and thiram may have influenced growth characteristics by inhibiting Al uptake of seedlings planted in acidic soil. To our knowledge, this is the first report on the influence of the fungicides captan and thiram on mineral ion uptake in roots. Chemical names used: p-Chloromercuribenzenesulfonic acid (PCMBS), dithiothreitol (DTT), N-trichloromethylthio-4-cyclohexene-1,2-dicarboximide (captan), tetramethylthiuram disulfide (thiram).

WATERMELON SEEDLING GROWTH AND ROOT CALCIUM ABSORPTION AS INFLUENCED BY THE FUNGICIDES CAPTAN AND THIRAM

Unilateral application of Ca2+ and Al3+ induced curvature in roots of `Starbrite' watermelon [Citrullus lanatus (Thumb.) Matsum and Nakai] seedlings from both untreated and commercially pretreated seeds. In untreated seeds, PCMBS inhibited root curvature by decreasing Ca2+ and Al3+ uptake. In pretreated seeds, PCMBS only inhibited Ca2+-induced root curvature. Captan and thiram inhibited Ca2+- or Al3+-induced root curvature. Captan showed the greatest inhibition of Ca2+ uptake at 100 mg/liter, whereas thiram was most effective at 0.01 mg/liter. The effects of captan and thiram were statistically additive. Thiram appeared to show a similar mode of action to PCMBS in affecting Ca2+ uptake. DDT reversed the inhibitory effect of thiram, but not that of captan.Acid soil (pH 4.6) reduced number of leaves, leaf, stem, shoot and whole plant dry weight, and stem length. Pretreated seeds produced greater root dry weight and root:shoot ratio in acid soil than did untreated seeds. Fungicides may have reduced Al3+ toxicity by inhibiting Al3+ uptake in acid soil.

Effects of Captan on DNA and DNA metabolic processes in human diploid fibroblasts.

The fungicide Captan has been examined for its effects on DNA and DNA processing in order to better understand the genotoxicity associated with this agent. Captan treatment resulted in production of DNA single strand breaks and DNA-protein cross-links and elicited an excision repair response in human diploid fibroblasts. Captan was also shown to inhibit cellular DNA synthesis and to form stable adducts in herring sperm and human cellular DNA. Misincorporation of nucleotides into Captan-treated synthetic DNA templates was significantly elevated in an in vitro assay using E. coli DNA polymerase I, suggesting that DNA adduct formation by Captan could have mutagenic consequences. In sum, these studies demonstrate that Captan is capable of interacting with DNA at a number of levels and that these interactions could provide the basis for Captan's genotoxicity. The extreme cytotoxicity of this fungicide, however, could be due to other cellular effects since at the IC50 for cell killing, approximately 0.8 microM, none of the above genotoxic events could be detected by the methods employed.

Interaction of captan with mammalian microtubules

Using turbidometry, electron microscopy and immunofluorescent microscopy experiments we studied the effect of captan, a widely used pesticide on mammalian microtubules and microfilaments. Turbidometry at 350 nm showed a dose-dependent inhibition of tubulin assembly incubated with captan. The pesticide, given at equimolar concentration with tubulin (30 microM), caused the total inhibition of microtubule formation, while at lower concentrations (5-20 microM) the inhibition of tubulin polymerization was less extensive. At the same concentration range (5-30 microM), captan also promoted the disassembly of performed microtubules. The results of the in vitro effects of captan with microtubules were confirmed in parallel by electron microscopic studies. In vivo, captan caused also depolymerization of microtubules in cultured mouse fibroblasts as shown by indirect immunofluorescent staining of tubulin. The extent of microtubules disassembly was concentration- and time-dependent. While incubation of the cells with 10 microM captan for 3 h disturbs totally the microtubular structures, incubation with 5 microM captan needs 12 h for the same effect. Recovery of microtubules was observed, when preincubated cells were extensively washed. No interaction of this drug with equimolar concentration of G- or F-actin could be observed in vitro, as shown by polymerization experiments. In line with this, the fluorescent actin pattern in mouse fibroblasts incubated with 10 mM captan for up to 12 h did not seem to be altered. From these results it is concluded that captan interacts in equimolar concentrations with tubulin affecting the assembly and disassembly of microtubules in vitro and in cultures of mammalian cells.

SELECTION FOR CAPTAN TOLERANCE IN THE Rhizobium phaseoli-Phaseolus vulgaris L. N2-FIXING SYMBIOSIS

Application of the seed-applied fungicides captan, DL-Plus, Evershield, thiram and Metalaxyl reduced nodulation in the field bean cultivar Lancer (Phaseolus vulgaris L.) in the field. Captan, Evershield, B3 and Thiram also lowered the acetylene reducing activity under the same conditions. Captan, DL-Plus, and B3 resulted in significant yield reductions of field bean inoculated with commercial multi-strain rhizobial inoculant. Since captan or captan-containing fungicides were the most potent inhibitors of symbiotic N2 fixation in field bean, spontaneous mutants of Rhizobium phaseoli strains 3644 and 8215 were selected on the basis of ability to grow in microbial medium containing 100 ppm of Captan 50 W. Controlled environment chamber and field evaluations indicated that all mutants were less sensitive to commercial rates of Captan 50 W (2.0 g per kilogram seed) than either parent strain or commercial multi-strain inoculant. Inoculation of captan-treated seed with these mutants 24 h prior to seeding did not affect nitrogenase activity or yield. Assessment of the effect of captan on the N2-fixing symbiosis and the captan tolerance of R. phaseoli strains by the acetylene reduction assay or 15N isotope dilution at levels of 15N natural abundance gave similar results. The existence of mutants of R. phaseoli tolerant to seed-applied captan but unaltered in symbiotic properties makes the combined use of captan as a seed protectant and seed-applied rhizobial inoculation fully compatible. Key words: Phaseolus vulgaris L., Rhizobium phaseoli, captan, N2 fixation, 15N isotope dilution, acetylene reduction

Effects of captan on the growth and cellulase production of Aspergillus aculeatus and Botryodiplodia theobromae

AbstractThe effects of captan on the production of mycelia and cellulolytic enzymes of Aspergillus aculeatus and Botryodiplodia theobromae were investigated in culture. There was decrease in mycelia of both fungi with increase in captan concentration in ppm. No fungal growth was recorded at 400 ppm. Captan at 10–50 ppm at 25 and 30 °C induced both fungi to produce more mycelia than in control cultures. The effect of captan concentration on the production of cellulases showed a decrease in quantity with increase in concentration. At 400 ppm no cellulase was produced by both fungi. There was a general decrease in cellulase production with increase in temperature either in control or experimental cultures. In cultures incorporated with captan, the cellulolytic activities of A. aculeatus (at 10 ppm) and B. theobromae (at 10 ppm, 50 ppm) were found to be relatively high.

Comparison of tillage methods on red clover and ryegrass establishment and production under grazing in the establishment year

Abstract ‘Grasslands Pawera’ red clover (Trifolium pratense L.) was drilled into perennial ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.)-dominant pasture in autumn and spring. A prototype drill equipped with a chisel coulter and band spray mechanism was used. At both dates Pawera was drilled into a cultivated seed bed, oversown or overdrilled into an undisturbed sward, and overdrilled into paraquat-sprayed bands. Effects of captan, phorate, methiocarb, and urea on red clover establishment were studied with autumn drilling. Spring drilling included blanket applications of paraquat and glyphosate and overdrilling of Pawera alone or with ‘Grasslands Nui’ perennial ryegrass. Sown plant survival and development, pasture production, and composition were evaluated under sheep grazing. After full cultivation, recovery of pasture production and red clover seedling development were more rapid for spring than autumn sowing. Compared to untreated pasture full cultivation reduced the establishment ye...

Neuere Antimycotika

The author investigated the coupling reactions of aryldiazonium salts with nitromethane and nitroethane and proved that only the coupling with 2-nitroaryldiazonium salts and their 4 substituted derivatives yields stable compounds. The author produced a number of nitromethanal-2-nitrophenylhydrazones and nitroethanal-2-nitrophenylhydrazones and investigated their fungistatic and fungicidal efficiency in vitro. For comparison sake he also investigated the fungistatic and fungicidal effect of 2-nitrophenylhydrazones of the cyanomethanal, mesoxalic-acid-dinitril, mesoxalic-acid-seminitril-ethylester and mesoxalic-acid-seminitril-amide because these compounds show a certain chemical analogy with nitromethanal-2-nitrophenylhydrazone. Simultaneously the author investigated the fungistatic and fungicidal effects of captan and thiram which represent two standard fungistatics in order to obtain comparable results. He proved that nitromethanal-2-nitrophenylhydrazone and its 4 substituted derivatives exert a widely spreading fungistatic effect. In contrast thereto the fungistatic range of nitroethanal-2-nitrophenylhydrazone is limited; only the trichophyton- and epidermophyton species are influenced by it. 2-Nitrophenylhydrazone of mesoxalic-acid-dinitril which bears an analogous structure to nitromethanal-2-nitrophenylhydrazone reveals fungistatic and fungicidal activity. Any further structurally analogous compounds of nitromethanal-2-nitrophenylhydrazones are totally ineffective on filamentous dermatophythons and also on phytopathogenic and saprophytic fungi strains. The author proved that the two standard fungistatics, captan and thiram, are on the whole as effective as nitromethanal-2-nitrophenylhydrazone as far as their fungistatic and fungicidal activities are concerned. The possibility of a practical administration of nitromethanal-2-ntrophenylhydrazones as fungistatics is discussed.

Effects of fungicides on physiology of phylloplane fungi

Effects of Captan, Dicloran, Thiram and Verdasan on the growth, germination, cellulose decomposition and starch hydrolysis of some phylloplane fungi isolated from fungicidetreated leaves were studied. Radial growth rates were reduced with increasing concentrations of the fungicides; Captan and Dicloran were less inhibitory compared with Thiram and Verdasan. The fungi could tolerate lower concentrations of the fungicides in liquid media than on solid media : 0.05 ppm of Verdasan prevented the mycelial growth of Drechslern biseptata (Sacc. & Roum.) Richardson & Fraser and Trichoderma viride Pers. ex Fr. Spore germination and germ-tube elongation were retarded at lower concentrations of fungicides than was mycelial growth. Concentrations of Captan and Dicloran of up to 50 ppm were only fungistatic to the spores of Alternaria alternata (Fr.) Keissler, Cladosporium cladosporioides (Fres.) de Vries and T. viride . Thiram at 50 ppm and Verdasan at 10 ppm and higher were fungicidal after exposure of the spores to the fungicides for 24 h. Cellulose decomposition and starch hydrolysis were inhibited by increasing concentrations of the fungicides. The higher concentrations of Thiram and Verdasan prevented the cellulolytic abilities of even the strongly cellulolytic species. The physiological data are discussed in relation to ecological studies on the effects of fungicides on the occurrence of phylloplane fungi.

Effects of Captan and Topsin-M on shoot blight of apricot

Effects of Captan and Topsin-M on shoot blight of apricot

A Phytotoxic Effect of Captan on the Growth of Conifer Seedlings

A Phytotoxic Effect of Captan on the Growth of Conifer Seedlings

Effect of captan and triethylenemelamine (TEM) on reproductive fitness of [formula omitted] mice

The specific mammalian mutagen bioassay system involving polygenic reproductive fitness was tested by using two generations of the offspring of captan treated male DBA 2J mice. The fungicide captan ( N-(trichloromethylthio)tetrahydrophthalimide) was given at doses of 50 or 100 mg/kg/day for 5 days. The known mutagen triethylenemelamine (TEM) was used as the positive control compound (0.1 mg/kg dose). TEM produced decreases in overall productivity (as measured by the fertility index) and decreased survival from birth to day 4, and from day 5 to weaning at 21 days. Captan treated animals also showed a decrease in fertility index, but neither dose of captan provoked the severity of decreases seen after TEM treatment. The decrease in average weaning weight seen in the first litter of the second generation after the high dose of captan suggests that the effects of captan on certain characteristics may be nearly as serious as those of TEM.