Concentrations Of Fenitrothion Research Articles

Fenitrothion‐induced alterations in ammonia metabolism in the crab, Oziotelphusa senex senex fabricius

AbstractFresh water crabs, (Oziotelphusa senex senex) were subjected to short‐term (1 day) and long‐term (30 days) exposure to a sublethal concentration of fenitrothion (0.04 mg litre‐1), and the hepatopancreatic nitrogen metabolism was investigated. Differential patterns of nitrogen metabolism were observed in the hepatopancreas in response to both short‐term and long‐term exposure. Levels of ammonia in hemolymph of crab after short‐term exposure were markedly increased, with an increase in excretion of ammonia. The activity levels of aspartate aminotransaminase (AAT), alanine aminotransaminase (AIAT) and glutamate dehydrogenase (GDH) were found to increase in the hepatopancreas during short‐term exposure, which suggests increased transamination and deamination of amino acids. The AMP‐deaminase activity increased in the hepatopancreas during short‐term exposure indicating increased deamination of nucleic acids. The activity levels of ornithine cycle enzymes such as arginino succinate synthetase (ArSS) and arginase indicated diminished activities resulting in a low level of operation of the urea cycle and consequent accumulation of ammonia during short‐term exposure. The whole view of ammonia production and utilization mechanisms suggests the probable synergistic manifestation of ammonia toxicity during short‐term fenitrothion poisoning.However, during long‐term exposure, the haemolymph had a low ammonia level. The excretion of ammonia was also found to decrease. The activity levels of AAT, AIAT and GDH in the hepatopancreas were found to increase. In contrast to these, the AMP‐deaminase activity decreased in the hepatopancreas suggesting decreased deamination of nucleic acids. ArSS and arginase activities increased indicating active operation of the urea cycle and consequent accumulation of urea. Glutamine synthetase activity rose with the accumulation of glutamine which may help in averting toxic effects of ammonia. The possible effects of fenitrothion toxicity on energy requirements, transdeamination patterns, ureogenesis and glutamine production have been discussed.

Atmospheric Concentration of Aerially Applied Fenitrothion.

The variation of fenitrothion (MEP) concentration in the atmosphere was investigated after the aerial application of MEP for the control of pine sawyer beetles in Niigata City. In the applied area, MEP in air (CA, μg/m3) was 5.2-100μg/m3 at maximal concentrations ; MEP was detected on 12d after the application. MEP was drifted to the points located 50-1000m from the applied area ; atmospheric MEP (C, μg/m3) were 0.19-1.1μg/m3 at maximal concentrations. C was mainly dependent on passing time after the application, wind direction, air temperature and the distance from the applied area. CA (n=37) was represented by multiple regression analysis as log CA=-1.007×log T+0.01290×cos θ-0.07283×υ-1+6.033×log t-6.416 (γ2=0.736) where T (h), v (m), θ and t (°C) are passing time after the application, wind speed, wind direction (0gθg180 ; θ=0 at a NW wind) and air temperature, respectively. C (n=122) was represented as log C=-0.3165×log T+0.2154×cos θ+0.6329×υ-1+3.094×log t-0.2642×log D+0.2833×CA-4.570 (γ2=0.763) where D (m) was 100 + the distance from the applied area.

Response and Recovery of Brain Acetylcholinesterase Activity in Atlantic Salmon (Salmo salar) Exposed to Fenitrothion

Atlantic salmon (Salmo salar) parr were exposed to a number of concentrations of either technical grade fenitrothion or an operational formulation of the pesticide for 7 d or to the operational formulation for two, 24 h periods separated by 7 d. Brain acetylcholinesterase (AChE) activity decreased as concentration, of fenitrothion increased. Recovery period was directly related to amount of depression, with recovery of AChE from exposure to 0.004 μL/L fenitrothion taking less than 1 wk. Samples must be taken soon after spray operations to detect exposure to such low levels of fenitrothion through AChE monitoring.

Effects of aerial spraying of insecticides on nontarget macrobenthos in a mountain stream

The effects of aerial spraying of an insecticide were investigated in a mountain stream using a drift net. The concentration of fenitrothion (organophosphorus insecticide) in the river water increased to ca. 20 μg liter −1 3 hr after the spraying and decreased exponentially to half the peak value after 2 hr. A large number of aquatic insects were found drifting after the spraying. The total number of individuals which drifted in the daytime after spraying reached nine times the number found the previous night. The total number of species which drifted during the 24 hr following the spray increased to 43 from 17 on the previous day. Before the insecticide spraying, the drifting benthos were almost entirely made up of three species of Baetis (Ephemeroptera). However, many individuals of several species of Heptageniidae (Ephemeroptera), Apsilochorema sutshanum (Trichoptera), and Chironomidae (Diptera) drifted in addition to Baetis after the spray. A large number of young Baetis, which had not been seen in the natural night drift samples, were found drifting due to the insecticide. Natural night drift almost disappeared from the day folowing insecticide spraying. At the second insecticide spraying, conducted 20 days after the first, the number of individuals which drifted during the 24 hr following spraying decreased to only 0.85% of that in the first spraying although changes in insecticide concentration showed a similar pattern. Several species of Ephemeroptera were dominant among the fauna in the studied stream, and the causal relationships of this are discussed.

An improved method to study the impact of pesticide sprays on small song birds

Four test groups of small songbirds (Zebra Finch, Poephila guttata) were sprayed in a chamber with varying concentrations of fenitrothion. Exposure levels were assessed by monitoring air concentrations, deposits of the active ingredient (AI) on glass plates and droplets/cm2 on Kromekote cards. All indices of exposure were linearly correlated and the mean AI deposit on glass plates for the four groups tested with equivalent to 38, 51, 139 and 255 g/ha or 14%, 18%, 50% and 91% of the highest permissible emitted rate for broadscale forest spraying in Canada. Significant depression in body weights and brain acetylcholinesterase levels were noted only for the highest exposure group. Fenitrothion residues in blood were detectable only at the highest exposure level, and in liver at the two higher levels. Carcass and feather residues were much higher than those in blood and liver, and were detectable at all exposure levels but the residues did not increase linearly with exposure. For one of the spray groups, we were able to compute an equivalent acute oral dose based on matching acetylcholinesterase inhibition.

Detection of S-methylfenitrothion, aminofenitrothion, aminofenitroxon and acetylaminofenitroxon in the urine of a fenitrothion intoxication case

A 23-year-old male attempted suicide by ingesting approximately 50 ml of 5% fenitrothion emulsion, and vomited soon afterwards. He was admitted to a hospital about 3 h after ingestion. He recovered and was discharged from hospital 3 days after admission. The serum cholinesterase activity (normal range: 175–440 I.U.) was only 29 at 3 h, 32 at 1 day, 59 at 2 days and 75 at 3 days after ingestion. Fenitrothion and its metabolites in the body fluids were extracted by an Extrelut ® column extraction method, detected by a gas chromatograph equipped with either a hydrogen flame ionization detector or a flame photometric detector, and confirmed by a gas chromatograph-mass spectrometer. Fenitrothion concentration in the blood was 169.5 ng/g at 3 h after ingestion. The half life of blood fenitrothion concentration was found to be about 4.5 h. Fenitrothion metabolites, 3-methyl-4-nitrophenol, aminofenitrothion, aminofenitroxon, acetylaminofenitroxon and S-methylfenitrothion, were detected in the urine samples. All of them except S-methylfenitrothion were detected in the urine samples collected up to 62 h after ingestion. It would appear therefore that fenitrothion poisoning can be determined by detection and analysis of the metabolites in urine even if fenitrothion has not been detected in the blood.

EVALUATION OF A HELD BIOASSAY TECHNIQUE TO PREDICT THE IMPACT OF AERIAL APPLICATIONS OF FORESTRY INSECTICIDES ON STREAM INVERTEBRATES

AbstractField bioassays were used to assess the toxicities of four formulated insecticides to representative stream invertebrates. Toxicities (48-h LC50) after a 1-h application period ranged from 2.0 to 7.1 μg/L for permethrin, 82 to 284 μg/L for fenitrothion, 344 to 1276 μg/L for aminocarb, and 251 to 1504 μg/L for mexacarbate. Invertebrates drifted at concentrations of permethrin greater than 0.5 μg/L, and at concentrations of fenitrothion, aminocarb, and mexacarbate greater than 10 μg/L. An aerial application of 280 g AI/ha fenitrothion with no stream buffer was made to compare bioassay results with impact to aquatic invertebrates under operational spray programs. Concentrations of fenitrothion peaked 30 min after spray at 31.0 μg/L and declined to less than 1.0 μg/L within 14 h. Numbers of drifting invertebrates increased 20-fold 3 h after spray and declined to before-spray numbers within 24 h. Mortalities of caged invertebrates in the stream ranged from 0% for Pycnopsyche sp. to 16% for Simulium venustum (Say). The field bioassay accurately predicted the impacts of fenitrothion on stream invertebrates in this situation.

Effect of safe concentrations of some pesticides on thyroid in the freshwater murrel, Channa punctatus: a histopathological study.

The effect of 'safe application rate (SAR)' concentrations of the insecticides fenitrothion 50% EC (an organophosphate) and carbofuran 3% G (a carbamate) on histopathological changes in the thyroid gland have been studied during chronic exposure for 120 days (mid-April to mid-August). The studies reveal significant declines in the diameters of the follicle and the colloid of the thyroid, but a significant increase in the height of the epithelium, following exposure to both fenitrothion or carbofuran. In the fenitrothion treatment, invasion by blood corpuscles into the follicular lumen, following breakdown of the epithelium, was also observed. The degeneration of the epithelium and the loss of colloid in the follicles suggest that the fenitrothion treatment is more severe than the carbofuran treatment.

Physiological Effects of Natural and Artificial Defoliation on the Growth of Young Crops of Lodgepole Pine

Field experiments involving naturally occurring population levels of larval European pine sawfly Neodiprion sertifer (Geoff. ) and artificial defoliation in both field and glasshouse experiments were used to investigate physiological effects of defoliation on lodgepole pine. Reductions in total projected leaf area, annual height and volume increments of 19, 33 and 32 per cent, respectively, were recorded on trees where larvae had consumed all mature foliage. Leader growth was up to 48 per cent less on defoliated trees after two years reflecting a delayed growth impact. Similar effects were found on trees which had been defoliated by hand in a manner resembling sawfly feeding. Artificial defoliation of transplants also showed that this type of damage can have serious consequences on below-ground growth, particularly of fine roots. Root:shoot ratios were found to be 0.64 in undamaged plants and 1. 05 in defoliated plants. A high concentration (1300 ppm) of the insecticide fenitrothion, used to maintain control treatments in the field, was found to have no significant effects on the major growth parameters being assessed.

Bioaccumulation, metabolism, and effects of DDT, fenitrothion, and chlorpyrifos onSaccharomyces cerevisiae

Saccharomyces cerevisiae accumulated DDT, fenitrothion, and chlorpyrifos rapidly from yeast glucose medium. The maximum concentrations of DDT, fenitrothion, and chlorpyrifos accumulated were 8,253, 18,960 and 11,579 μg/g (dry wt), respectively. The pattern of accumulation was similar for all insecticides. The bioconcentration factor was inversely proportional to insecticide solubilities.Saccharomyces metabolized the three insecticides, but only two metabolites of DDT (DDD and DDE) were identified. Protoplast cultures were more sensitive to DDT and fenitrothion compared to normal cultures but were less sensitive to chlorpyrifos. Both the normal and protoplast cultures recovered from the toxic effect after 24 hr.

Effect of safe concentrations of some pesticides on testicular recrudescence in the freshwater murrel, Channa punctatus (Bl.): A morphological study

The effects of safe concentrations of fenitrothion 50% E.C., an organophosphate, and carbofuran 3% G, a carbamate, on testicular recrudescence of Channa punctatus during the maturing, prespawning, and spawning phases (15th April through 12th August, 1980) of the annual reproductive cycle have been studied. The results reveal that compared to the carbofuran treatment, the fenitrothion treatment was more effective in lowering testicular weights. Furthermore, the carbofuran treatment delayed the formation of spermatids and sperm, since their occurrence in the testes was observed at 90 days of exposure, but at 60 days of exposure in the control fish. The fenitrothion treatment not only delayed the formation of spermatids, but also arrested the formation of sperm, since most of the spermatids had undergone necrosis. The exposure for 120 days to safe concentrations of carbofuran/fenitrothion also resulted in the necrosis of spermatogonia and spermatocytes, which led to their gradual loss. As such, the lobules completely devoid of the spermatogenetic stages were observed in the testes of the treated fish. The occurrence of such empty lobules, however, was relatively greater in the fenitrothion-treated fish. The formation of the collagenous capsules around the necrotic germ cells was also observed in the treated fish testes. The interstitial (Leydig) cells were in the involuted condition in the treated fish testes, but active in the control fish.

EFFECTS OF FENITROTHION INSECTICIDE ON INHABITANTS OF LEAVES OF THE PITCHER PLANT, SARRACENIA PURPUREA L.

AbstractBy injecting fenitrothion into fluid in leaves of pitcher plants, Sarracenia purpurea L., it was determined that the mosquito, Wyeomyia smithii (Coquillett), and the midge, Metriocnemus knabi (Coquillett), are under some risk from fenitrothion forest sprays at the rate of 210 g AI/ha. Wyeomyia smithii is slightly more susceptible than is M. knabi. Other leaf inhabitants, mites and rotifers, were not affected by initial concentrations of fenitrothion in the fluid (up to 9.6 μg/L) that did affect the mosquito and the midge.

Stochastic modeling of the insecticide fenitrothion in water and sediment compartments of a stagnant pond

A stochastic model is developed for the behavior of the insecticide fenitrothion's decomposition in a New Brunswick (Canada) stagnant pond after aerial spraying. The concentrations of fenitrothion are modeled in two pond compartments: water and bottom sediments. Assuming first‐order kinetics, a mass balance equation of fenitrothion is written for each of the compartments. The deterministic model is obtained by integrating the linear system of differential equations. The stochastic model arises by considering both the initial condition in the water compartment and the input term in the sediment compartment to be stochastic, which results in a stochastic differential equation (SDE). The moment equation, derived from the Itô stochastic differential rule, provides the moment solution to the SDE. Temporal expectations and heteroscedastic variance models are thus obtained. The model is calibrated using observations obtained from fenitrothion sampling at three different locations in each of the pond's compartments. The stochastic model performs satisfactorily.

Comparative metabolism of fenitrothion in aquatic organisms: III. Metabolism in the crustaceans, Daphnia pulex and Palaemon paucidens

When the waterflea Daphnia pulex and the shrimp Palaemon paucidens were exposed to 1.0 ppb[ 14C]fenitrothion in a flowthrough system, the concentrations of fenitrothion and 14C in the body reached equilibrium, and the maximum bioaccumulation ratios of fenitrothion were 71 and 6 in the daphnia and shrimp, respectively. These crustaceans primarily metabolized the compound by oxidation of PS to PO, hydrolysis of PO-aryl linkage, and demethylation. The liberated phenol was found to be conjugated with sulfate in the daphniaand with glucose in the shrimp. When the organisms were transferred to a freshwater stream, fenitrothion and its metabolites were rapidly excreted from their bodies, and the half-life of the parent compound was less than 0.2 day in both species.

Comparative metabolism of fenitrothion in aquatic organisms: II. Metabolism in the freshwater snails, Cipangopaludina japonica and Physa acuta

When freshwater snails, Cipangopaludina japonica and Physa acuta, were exposed to 0.1 ppm [ 14C]fenitrothion in a dynamic flow system, the concentrations of fenitrothion and 14C in the body reached equilibrium on Day 1 of exposure. The maximum bioaccumulation ratios of fenitrothion were 18 and 53 in C. japonica and P. acuta, respectively. These snails metabolized the compound primarily by demethylation, hydrolysis, and reduction. The liberated phenol moiety was found to be conjugated with sulfate in C. japonica and mainly with glucose in P. acuta. When the snails were transferred to a freshwater stream, fenitrothion and its metabolites were rapidly excreted, and the half-life of the parent componnd was less than 0.5 day in both snails. Fenitrothion and its decomposition products were mainly distributed in liver of P. acuta, as evidenced by whole-body radioautography.

Effect of safe application rate (SAR) concentrations of some biocides on the gonads of the fresh water murrel, Channa punctatus (Bl.)—A biochemical study

The effect of safe application rate (SAR) concentrations of fenitrothion 50% EC—an organophosphate and carbofuran 3% G—a carbamate on the gonads (ovaries/testes) of Channa punctatus was studied for 120 days (mid-April through mid-August) extending over the preparatory, prespawning, and spawning phases of annual reproductive cycle. The studies have revealed that the levels of total proteins, RNA, total lipids, and ascorbic acid decreased, while those of the cholesterol and the phospholipids increased following exposure to the two biocides. Furthermore, it was observed that in both treatments the decline in the levels of total proteins, RNA, total lipids, and ascorbic acid was relatively more marked in the testes than in the ovaries. On the contrary, increase in the levels of cholesterol was relatively more in the ovaries, while increase in the levels of phospholipids was more in the testes in both treatments. The results suggest that the decrease/increase in the levels of the above-mentioned biochemical parameters was more in the fenitrothion treatment than in the carbofuran treatment and, therefore, may be considered relatively more toxic to this species.

Studies on the relation between toxicity and metabolism of organophosphorus insecticides in shrimps. I. Metabolism of an organophosphorus insecticide, fenitrothion, in tiger shrimp Penaeus japonicus.

A study has been made of the toxicity, absorption and metabolism of fenitrothion [O, O-dimethyl O-(3-methyl-4-nitrophenyl)phosphorothioate; Sumithion] in tiger shrimp Penaeus japonicus, as the first step to elucidate the cause for the occurrence of its high toxicity to the shrimp.The 24-h LC50 value of fenitrothion for tiger shrimp was about 1 ppb, while that for fish was roughly 6ppm. After 0.5-24h exposure to 0.5 ppb [14C] fenitrothion, [14C]fenitrothion and its metabolites accumulated in the shrimp were extracted with benzene and separated by thin-layer co-chromatography with non-radioactive fenitrothion and its authentic metabolites. After 4-h exposure, the concentration of fenitrothion was almost equilibrated at a level of ca. 6.5pmol/g shrimp, which corresponded to a bioconcentration ratio of 3.6, whereas the concentrations of its metabolites, especially 3-methyl-4-nitrophenol, increased with exposure time. At 24-h exposure, the amounts of fenitrothion, fenitrooxon, desmethylfenitrothion, desmethylfenitrooxon and 3-methyl-4-nitrophenol accumulated in the shrimp were 6.3, 2.9, 3.6, 6.2 and 74.3 pmol/g, respectively. The amounts of the conjugated 3-methyl-4-nitrophenol extracted with ethyl ether after benzene-extraction increased with exposure time and reached 104pmol/g at 24-h exposure, which was almost the same level of the benzene-extract.

Fate of fenitrothion in several developmental stages of the killifish (Oryzias latipes)

14C-Fenitrothion at 0.1 ppm in running water, is rapidly absorbed at each stage of the embryo, yolk sac fry, postlarva, juvenile, and adult of the killifish (Oryzias latipes). The14C and fenitrothion concentrations 2 in organisms including those in eggs produced from mature female reach equilibrium after 1 to 3 days exposure except the juvenile stage, which shows a gradual increase in concentration, and the maximum bioaccumulation ratios 3 of the parent compound ranges from 88- (postlarva) to 540-fold (female adult) relative to the water concentration.

Partitioning and short-term persistence of fenitrothion in New Brunswick (Canada) headwater streams

There were no consistent differences in concentration of fenitrothion in streamwater with depth, or between midstream and slow water at the stream edge. This was true of both aqueous and oilbased formulations. A large proportion of the fenitrothion was taken up by suspended material; in sediment, it was taken up mainly by the organic fraction.

Increase in membrane permeability of electrolytes and betacyanin in beet root disc by fenitrothion

Effect of fenitrothion (phosphorothioic acid, 0,0-dimethyl 0-4-nitro-m-tolyl ester), an organophosphorous insecticide, on membrane permeability employing the leakage of betacyanin and electrolytes as the criteria were studied in beet root(Beta vulgaris) discs. The leakage of both betacyanin and electrolytes increased with increasing concentrations (10–150 ppm) of fenitrothion in the incubation medium. At 0.33 mM the increase in electrolyte leakage was approximately linear for the first 6h, while the increase in betacyanin leakage started with a lag of about 2 h. Long term incubation (24 h) showed a biphasic nature (in the semilog plot) for the increase in betacyanin leakage, while the increase in electrolyte leakage appeared more complex. In the control sample, the Arrhenius plots (25–50°C) of leakage showed a break at 40°C. In treated samples no break was observed, but the slope decreased (for both electrolyte and betacyanin leakage) as compared to the respective slopes in the control in the temperature region greater than 40°C. The results are discussed in terms of the possible effect of the insecticide on the active transport in plant membranes