Comparison of the partitioning of pesticides relative to the survival and behaviour of exposed amphipods

Pesticides sprayed on farmlands can end up in rivers and be transported into estuaries, where they could affect aquatic organisms in freshwater and marine habitats. A series of experiments were conducted using the amphipod Corophium volutator Pallas (Amphipoda, Corophiidae) and single pesticides, namely atrazine (AT), azinphos-methyl (AZ), carbofuran (CA) and endosulfan (EN) that were added to sediments and covered with seawater. Our goal was to compare the concentrations affecting the survival of the animals relative to potential attractant or repellent properties of sediment-spiked pesticides. The avoidance/preference of contaminated/reference sediments by amphipods was examined after 48 and 96 h of exposure using sediments with different organic carbon content. The octanol–water partition coefficients (log K_ow) ranked the pesticides binding to sediments as EN > AZ > AT > CA. LC₅₀ and LC₂₀ covered a wide range of nominal concentrations and ranked toxicity as CA-AZ > EN > AT. Under the experimental set up, only EN initiated an avoidance response and the organic carbon normalised concentration provided consistent results. Using the present data with wide confidence limits, >20% of a population of C. volutator could perish due to the presence of EN before relocation or detecting CA or AZ in sediments by chemical analysis.     

Sensitivity to tri-o-cresylphosphate neurotoxicity on n-hexane exposed hens as a model of simultaneous hexacarbon solvent and organophosphorus occupational intoxication

Hens were given a single oral dose (0.235 mg/kg) of tri-o-cresylphosphate (TOCP) during chronic n-hexane treatment (200 mg/kg daily, 5 days/week). They were compared with other animals treated only with n-hexane or only with TOCP. Animals treated with a higher TOCP dose (1 ml/kg) were used as positive controls. The animals treated with both n-hexane and TOCP showed rapid development of severe ataxia. The rate of the ataxia development was similar to that of the positive controls but with earlier onset of the first signs and with less loss of body weight. However, animals treated only with n-hexane, under the same conditions, showed only reversible weakness and sedative effects, and those treated only with TOCP showed slow and slight ataxia development. The n-hexaneand TOCP-treated hens showed axonal swelling with myelin retraction associated with Ranvier's nodes, which is characteristic of long hexacarbon exposure. Some internodal swellings were also observed but less frequently than the paranodal swellings. The time course of the ataxia development was similar to an organophosphorus-induced delayed neuropathy (OPIDN); however, the light microscopy observation more closely resembled hexacarbon neuropathy. The results suggest a potentiation effect of n-hexane and TOCP neurotoxicities which could be related to some human occupational neuropathies.Partial results of this work were previously presented at the XXIVth Congress of the European Society of Toxicology (Rome, March 1983) and at the V Jornadas Toxicológicas Españolas (Madrid, November 1983)Work partly supported by a grant No. 84/1833 from the Fondo de Investigaciones Sanitarias de la Seguridad Social of Spain. M. C. Pellin is a recipient of a followship from the Generalität Valenciana     

Unilateral neonatal intracerebroventricular 6-hydroxydopamine administration in rats: I. Effects on spontaneous and drug-induced rotational behaviour and on postmortem monoamine levels

6-Hydroxydopamine (6-OHDA; 100 µg in 5 µl) was injected into the right ventricle (intracerebroventricular, ICV) of 3-day old Sprague-Dawley rats in an attempt to produce a unilateral neonatal dopamine (DA) lesion. At adult stage, the rats were studied for spontaneous, handling- and drug-induced rotational behaviour. The 6-OHDA-treated rats showed hyperreactivity at handling, in the animal facility and in the experimental sets. This behaviour was not observed in vehicle-treated rats, and it did not decrease through the successive experiments. Apomorphine (0.05–1 mg/kg, SC) and caffeine (20 mg/kg SC) produced contralateral rotation in neonatal 6-OHDA, but not in vehicle-injected rats.d-Amphetamine (0.2–2 mg/kg, SC) produced strong, dose-dependent, ipsilateral rotation, while the serotonin (5-HT) releasing agent,p-chloroamphetamine (2 mg/kg, SC) produced a short-lasting and weak ipsilateral rotation in the 6-OHDA-treated rats. On the 6-OHDA-injected side, DA and metabolites levels were reduced by >70–90% in the striatum, the nucleus accumbens and the tuberculum olfactorium, while in the mesencephalon a 50% decrease was found. On the contralateral side, restricted decreases in DA and metabolites were observed. Noradrenaline (NA) levels were decreased bilaterally in the forebrain. In contrast, 5-HT and 5-hydroxyin-doleacetic acid (5-HIAA) levels were increased in the ipsilateral striatum (>180%), and tuberculum olfactorium (>120%). Thus, neonatal unilateral ICV 6-OHDA administration produced a significant unilateral decrease in tissue levels of DA and metabolites, which was most marked in the striatum. Changes in NA and 5-HT levels were also found in telencephalic and mesencephalic regions. The 6-OHDA lesion led to a lasting handling-related hyper-reactivity and, following stimulation with direct or indirect DA agonists, to rotational behaviour with a pattern similar to that observed in rats unilaterally lesioned at adult stage with 6-OHDA.     

Effect of polysaccharide from cultured Cordyceps sinensis on immune function and anti-oxidation activity of mice exposed to 60Co

Aim of the study

The present study was designed to investigate the molecular weight (MW), chemical composition and effect of polysaccharide (CS-PS), from the fruiting bodies of cultured Cordyceps sinensis, on immune function and anti-oxidation activity of BALB/c mice exposed to ⁶⁰Co.

Materials and methods

The MW of CS-PS was determined by gel-filtration. The chemical composition of CS-PS was tested by using gas chromatography–mass spectrophotometer (GC–MS). Mice were administered CS-PS with doses of 50, 100 or 200 mg/kg body weight, then exposed to ⁶⁰Co. The normal control group and irradiated control group were also used. Four days later, lymphocyte proliferation, activity of macrophage phagocytosis, delayed type hypersensitivity (DTH), concentration of malondialdehyde (MDA), total-superoxide dismutase (SOD) enzyme activity, and cytokine expression in serum from the mice were tested.

Results

The average molecular weight of CP-PS was 12 kD. The polysaccharide was composed of mannose, rhamnose, arabinose, xylose, glucose and galactose. Lymphocyte proliferation, the activity of macrophage phagocytosis, DTH and total-SOD enzyme activity in the CS-PS groups were significantly enhanced compared to the irradiated control group. Lipid peroxidation level was significantly reduced in the CS-PS groups compared to the irradiated control group. Levels of cytokine IL-4, IL-5 and IL-17 are also affected in the CS-PS groups compared to the irradiated control group.

Conclusions

CS-PS, a heteropolysaccharide, enhances immunity activity in mice treated by ionizing radiation, through reducing oxidative injury and modulating the secretion of cytokine IL-4, IL-5 and IL-17.     

Activity of N-acetyl-beta-glucosaminidase in lymphocytes of rats exposed to mixture of nitrogen oxides and chlorine

Activity of N-acetyl-beta-glucosaminidase (GS) has been cytochemically studied in peripheral blood lymphocytes of rats exposed to the mixture of nitrogen oxides (1.22 mg/m³) and chlorine (1.02 mg/m³) during a period of 12 weeks. The decrease of the total lymphocyte count and an increase of the count of GS-positive lymphocytes with cytoplasmatic but not exclusively lysosomal localization have been noted after exposure. The increase of the count of lymphocytes containing the enzyme within both lysosomal granules and cytoplasm has been correlated with the exposure time and accompanied by diminishing the count of lymphocytes containing the enzyme within the lysosomal granules exclusively. The authors believe the changes noted above may result from toxic damage of lysosomes or the immune response of lymphocytes against antigens released from the damaged tissues.     

Natural feed additive of Macleaya cordata: Safety assessment in rats a 90-day feeding experiment

Macleaya cordata (Willd.) (Papaveraceae) is used as an active component in the natural feed additive Sangrovit^®. Sangrovit^® contains mixture of the intact aerial parts and the fraction of quaternary benzo[c]phenanthridine alkaloids from M. cordata (FQBA). In a 90-day pilot toxicity trial, Sangrovit^® and the FQBA were tested for safety. Male Wistar rats were fed for 90 days with 100, 7000 or 14000 mg of Sangrovit^® or 600 mg of FQBA in 1 kg of feed. Body and organ weights, clinical chemistry and hematology markers, oxidative stress parameters, morphological structure of tongue, liver, ileum, kidney and heart samples, and total cytochrome P450 in liver were monitored. The results showed no statistically significant alterations in any parameter between control and treated animals, except for the group treated with 14000 ppm Sangrovit^® that resulted in elevation of reduced glutathione level and superoxide dismutase activity in liver.     

Expression of glutathione S-transferase (GST) genes in the marine copepod Tigriopus japonicus exposed to trace metals

The intertidal copepod, Tigriopus japonicus has been recognized as a potential model species for marine pollution toxicity testing. Toxicity ranges of several biocides, endocrine-disrupting chemicals (EDCs), and trace metals are known in T. japonicus. A large number of expressed sequence tags (ESTs) and genomic DNA are also sequenced from T. japonicus. In this study, expression of ten glutathione S-transferase (GST) genes was studied in the copepods exposed to trace metals. Expression of these genes was also studied against exposure to hydrogen peroxide (H(2)O(2)) used as a positive control with prooxidant activity. Of all genes, expression of GST-Sigma (GSTS) was highly upregulated in H(2)O(2) as well as trace metal-exposed copepods. In the time-course study, expression of GSTS mRNA was more consistent compared to other GSTs such as GST-Omega, GST-Delta1, GST-Theta3 or microsomal GST1 (mGST1). GSTS is predominantly reported from the insects. Coupled with the previous study of the in vitro antioxidant role of T. japonicus GSTS, these findings imply an antioxidant role for GSTS and highlight its importance as a biomarker of exposure to trace metals in T. japonicus. However, further validation and field trials would be necessary to propose GSTS gene expression as biomarker of exposure to trace metals, as for some trace metals such as silver the response was not consistent in concentration and time-series exposure experiments.     

Structural changes of Artemia parthenogenetica (Bowen and Sterling, 1978) (Branchiopoda-Anostraca) exposed to lead acetate

The cosmopolitan genus Artemia occurs both in saline or hypersaline waters and Artemia species are sensitive indicator organisms for environmental contamination. Scientists propose that the brine shrimp (Artemia) is a very suitable candidate for the development of identifying chemicals with adverse effects in aquatic ecosystems.In the present study, we investigated 24 h the short-term toxicity of lead acetate on Artemia parthenogenetica by using electron microscopy techniques. The ultrastructural changes were studied control group and experimental group. Analysing cellular structure, structure of organelles and vacuolization were observed. The number of cells based on the toxic effects of lead acetate was increased compared with the control group.     

Trophic transfer of Cd from larval chironomids (Chironomus riparius) exposed via sediment or waterborne routes, to zebrafish (Danio rerio): tissue-specific and subcellular comparisons

Zebrafish were fed chironomid larvae (8% wet weight daily ration) for 7 days, followed by 3 days of gut clearance in a static-renewal system. Regardless of whether the chironomids had been loaded with Cd via a waterborne exposure or sediment exposure, they had similar subcellular distributions of Cd, with the largest areas of storage being metal rich granules (MRG) > organelles (ORG) > enzymes (ENZ) except that sediment-exposed chironomids had significantly more Cd in the metallothionein-like protein (MTLP) fraction, and significantly less Cd in the cellular debris (CD) fraction. When zebrafish fed sediment-exposed chironomids (153 ± 11 μg Cd/g dry weight) were compared directly to zebrafish fed waterborne exposed chironomids (288 ± 12 μg Cd/g dry weight), identical whole-body Cd levels were observed, despite the difference in the concentration in the food source. Thus trophic transfer efficiency (TTE) of Cd was significantly greater from sediment-exposed chironomids (2.0 ± 0.5%) than from waterborne-exposed chironomids (0.7 ± 0.2%). Subsequent tests with waterborne exposed chironomids loaded to comparable Cd concentrations, as well as with Cd-spiked manufactured pellets, demonstrated that TTEs were concentration-independent. In all treatments, zebrafish exhibited similar subcellular storage of Cd, with the greatest uptake occurring in the ORG fraction followed by the ENZ fraction. However, neither trophically available metal (TAM) nor metabolically available fractions (MAF) were good predictors for the TTEs found in this study. Tissue Cd concentrations were highest in the kidney and gut tissue, then liver, but lower in the gill, and carcass. Overall, the gut and carcass contributed ≥71% to total body burdens on a mass-weighted basis. This study presents evidence that Cd may be acquired by fish from natural diets at levels of environmental relevance for contaminated sites, and that the exposure route of the prey influences the TTE.     

Transcript profiling and DNA damage in the European eel (Anguilla anguilla L.) exposed to 7,12-dimethylbenz[a]anthracene

The molecular responses induced during and after an acute exposure to 7,12-dimethylbenz[a]anthracene (DMBA) were analysed in liver, gill and blood cells of juvenile Anguilla anguilla with the aim of developing molecular biomarkers of environmental PAH pollution. Changes in the mRNA expression levels of the cell cycle checkpoint-related rad1 gene and the mRNAs of differentially expressed genes by suppression subtractive hybridization (SSH) were analysed in the liver, and related to well-established biomarkers: cyp1A1 mRNA expression and assessment of the DNA integrity using the comet assay and flow cytometry. DMBA exposure resulted in increased cyp1A1 mRNA levels, suggesting that cyp1A1 might be involved in the metabolism of DMBA. Global DNA damage, detected by the comet assay, was observed in the three tissues analysed but only blood cells showed chromosomal lesions as analysed by flow cytometry. Although DNA damage was found in the liver, no induction in rad1 gene was observed in this organ. The global SSH approach revealed that mRNAs of genes related to xenobiotic metabolism, immune processes and cytoskeleton dynamics were differentially expressed in DMBA-exposed eel livers, highlighting the complexity in the response observed in fish exposed to a genotoxic agent and providing directions for new biomarker development.     

Glutathione S-transferases M1 and T1 polymorphisms and arsenic content in hair and urine in two ethnic clans exposed to indoor combustion of high arsenic coal in Southwest Guizhou, China

A total of 2,402 cases of arsenic-related skin lesions (as of 2002) in a few villages of China’s Southwest Guizhou Autonomous Prefecture represent a unique case of endemic arseniasis related with indoor combustion of high arsenic coal. A significant difference of skin lesion prevalence was observed between two clans of different ethnicities (Hmong and Han) in one of the hyperendemic villages in this prefecture. This study was focused on a possible involvement of GST T1 and M1 polymorphisms in risk modulation of skin lesions and in the body burden of As in this unique case of As exposure. GST T1 and M1 polymorphisms were genotyped by an allele-specific PCR-based procedure. Total As contents in hair and urine samples as well as environmental samples of the homes of the two ethnic clans were analyzed. No significant deviations in the population frequencies of GST T1 and M1 0/0 genotypes or their combination were recorded between diagnosed skin lesion patients and asymptomatic individuals in both clans. Significantly higher As contents in hair and urine were observed in GSTM1 0/0 carriers, not in GSTT1 0/0 carriers. After stratified by ethnicity and gender, a statistically significant association of the GSTM1 0/0 genotype and higher As content in hair was only confirmed in the subgroups of ethnic Han clan members and all male villagers, not in ethnic Hmong clan members or in females. GST T1 and M1 homozygous deletions were not associated with an increased susceptibility to skin lesions in long-term exposure to indoor combustion of high As coal. The polymorphic status at the locus of GSTM1 might modulate individual’s body burden of total As in some Chinese ethnic groups.     

Effects of Substrate Salinity on Early Seedling Survival and Growth of Scirpus robustus Pursh and Spartina alterniflora Loisel

Rooted aquatic plants are being used increasingly to test the toxicity of sediments. However, effects of naturally occurring substrate constituents on most potential test species are not well understood even though their effects could affect the test results. The objective of this study was to determine the effect of substrate salinity (NaCl) on early seedling survival and growth of the emergent macrophytes, Scirpus robustus Pursh and Spartina alterniflora Loisel. Results of four 21- and 28-day toxicity tests, conducted in an artificial sediment, indicated interspecific differences in NaCl sensitivity when based on changes in shoot, root and whole plant dry-weight biomass. Concentrations of 7.8 g NaCl/ and 19.2 g NaCl/ first reduced early seedling biomass of S. robustus and S. alterniflora (P < 0.05), respectively, when compared to plants grown in sediment containing no measurable salinity. Seedling survival was not affected at average concentrations of 17.5 g NaCl/ or less for S. robustus and 22.3 g NaCl/ or less for S. alterniflora. The results indicate that substrate salinity is an important consideration in the selection of test species for laboratory phytotoxicity tests conducted with estuarine sediments, particularly if determination of chronic toxicity attributable to anthropogenic contamination is the primary objective.     

Microdialysis as a tool to determine free kidney levels of voriconazole in rodents: a model to study the technique feasibility for a moderately lipophilic drug

Microdialysis has been employed for the in vivo measurement of endogenous compounds and a variety of drugs in different tissues. The applicability of this technique can be limited by drug lipophilicity which can impair the diffusion through dialysis membrane. The objective of this study was to evaluate the feasibility of using microdialysis to study kidney penetration of voriconazole, a moderately lipophilic antifungal triazolic agent (LogD7.4=1.8). Microdialysis probe recoveries were investigated in vitro by dialysis and retrodialysis using four different drug concentrations (0.1-2 microg/mL) at five flow rates (1-5 microL/min). Recoveries were dependent on the method used for the determination as well as on the flow rate, but independent of drug concentration. The average apparent recoveries determined by dialysis and retrodialysis, at flow rate of 2 microL/min, were 21.1+/-1.5% and 28.7+/-2.0%, respectively. Recovery by retrodialysis was bigger than the recovery by dialysis. The average apparent dialysis/retrodialysis recovery ratio in vitro was 0.73 for all concentrations investigated. The differences between retrodialysis and dialysis recoveries were attributed to the drug's binding to the plastic tubing before and after the dialysis membrane which was experimentally evaluated and mathematically modeled. The in vivo apparent recovery determined by retrodialysis in healthy Wistar rats' kidney was 38.5+/-3.5%, similar to that observed in vitro using the same method (28.7+/-2.0%). The in vivo apparent recovery after correcting for plastic tubing binding (25.1+/-2.8%) was successfully used for determining free kidney levels of voriconazole in rats following 40 and 60mg/kg oral dosing. The results confirmed that microdialysis can be used as sampling technique to determine free tissue levels of moderately lipophilic drugs once the contribution of tubing binding and membrane diffusion on the apparent recovery are disentangled.     

A comparative study of d- and l-amphetamine on the open field performance of rats

Behavioural effects in the Open Field test following the administration of d- and l-amphetamine were compared in rats. A significant difference was found between the effects of the two isomers on horizontal activity, d-amphetamine alone causing horizontal stereotypy. In both cases dose-response relations were curvilinear. On the other hand, although both isomers produced vertical stereotypy, the dose-response relations were generally monotonic increasing with no signifiacnt differences between isomers. These differential effects on behaviour have been explained on the basis of stereospecificity of adrenergic neurons for amphetamine. The results of the study are consistent with earlier hypotheses that the horizontal and vertical stereotyped behaviours of rats in the Open Field situation are functions of brain noradrenergic and dopaminergic systems, respectively.     

The hydroxyl radical generation and oxidative stress for the earthworm Eisenia fetida exposed to tetrabromobisphenol A

Biochemical effects of tetrabromobisphenol A (TBBPA) on the earthworm Eisenia fetida, including superoxide dismutase, catalase, glutathione-S-transferase, reduced glutathione, oxidized glutathione, GSH/GSSG ratio and malondialdehyde (MDA) level, were measured to assess ecological toxicity of TBBPA. With OECD standard filter-paper contact test method, earthworms were exposed to TBBPA of a range of concentrations (0.00, 0.01, 0.05, 0.1, 0.5 and 1.0 mg L⁻¹). According to the electron paramagnetic resonance spectrum, reactive oxygen species (ROS) generated in the earthworm was identified as the hydroxyl radical (^•OH) which was significantly induced at all TBBPA concentrations. With the increasing of TBBPA concentration, the antioxidant enzymes, glutathione and MDA levels varied significantly. The results showed that TBBPA exerts its toxic effects on E. fetida by inducing the generation of ROS and resulting in oxidative damage. The results show that the ^•OH production leads to oxidative stress in the tissues of the earthworm E. fetida.     

Extrapolation of the laboratory-based OECD earthworm toxicity test to metal-contaminated field sites

The effects of cadmium, copper, lead and zinc on survival, growth, cocoon production and cocoon viability of the earthworm Eisenia fetida (Savigny) were determined in three experiments. In experiment 1, worms were exposed to single metals in standard artificial soil. For experiment 2, worms were maintained in contaminated soils collected from sites at different distances from a smelting works situated at Avonmouth, south-west England. In experiment 3, worms were exposed to mixtures of metals in artificial soil at the same concentrations as those present in the field soils. A survey of earthworm populations was carried out also. Population densities and species diversities of earthworms declined with proximity to the smelting works. No earthworms were found within 1 km of the factory. Comparison of toxicity values for the metals determined in the experiments indicated that zinc is most likely to be limiting earthworm populations in the vicinity of the works. Zinc was at least ten times more toxic to E. fetida in artificial soil than in contaminated soils collected from the field. This difference was probably due to the greater bioavailability of zinc in the artificial soil. The results are discussed in the context of setting protection levels for metals in soils based on laboratory toxicity data.     

RETRACTED ARTICLE: The retention behavior of ginsenosides in HPLC and its application to quality assessment of Radix Ginseng

This study systematically investigated the retention behavior of seven neutral ginsenosides Rg₁, Re, Rf, Rb₁, Rb₂, Rc, Rd, and an acidic ginsenoside R₀, the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxanebonded silica gel column. Based on the ginsenosides’ retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng. This article was retracted as it was printed by error in this issue of APR.     

Failure of naloxone to modify the effects of chlorpromazine and d-amphetamine on avoidance behavior in the squirrel monkey

Lever-pressing by squirrel monkeys was maintained under a continuous avoidance schedule in which each response postponed for 30 s the delivery of an electric shock to the tail. Dose-response curves were determined for chlorpromazine (0.03–0.3 mg/kg) and d-amphetamine (0.03–1.0 mg/kg) administered alone and administered concomitantly with 1.0 or 10 mg/kg of aaloxone. The dose-response curves for chlorpromazine and d-amphetamine were similar to those previously reported for monkeys under other schedules of shock-maintained behavior: Chlorpromazine decreased responding in a dose-related manner while d-amphetamine increased responding at low doses and disrupted behavior at the highest dose. Naloxone did not modify the effects of chlorpromazine, and d-amphetamine. These results suggest that interactions observed previously between naloxone and nonopiate drugs on behavior in pigeons and rodents are not general phenomena in all animal species.     

Phytohormone levels in germinating seeds of Zea mays L. exposed to selenium and aflatoxines

Seeds of Zea mays L. were exposed to aflatoxine B1 (AFB1), aflatoxine G1 (AFG1) and selenium (Se) alone and in combination and allowed to germinate. Phytohormone levels of GA-like substances (GAs), trans-Zeatin (t-Z) and Indole-3-acetic acid (IAA) were determined by High Performance Liquid Chromatography (HPLC) when the roots of the germinating seeds reach 1.5–3.0 cm in length. The levels of endogenous hormones decreased in seeds treated with AFB1 and AFG1 compared to control; however an increase was noted in seeds exposed to AFG1 and Se together. AFB1 and Se treatment caused reduced hormone levels in most of the treatments. When plants were exposed to Se alone, the highest levels of GAs, t-Z and IAA were observed in the application of 800 ppm Se. The highest levels of GAs, t-Z and IAA were observed when seeds were treated with 0.2 ppm AFG1 + 8 ppm Se, 0.2 ppm AFG1 + 8 ppm Se and 0.2 ppm AFG1 + 0.08 ppm Se, respectively, whereas the lowest levels of the hormones were observed in 0.2 ppm AFB1 + 8 ppm Se, 0.2 ppm AFB1 + 0.08 ppm Se and 0.1 ppm AFB1, respectively. In conclusion, the levels of phytohormones were reduced by the treatment of AFB1 and AFG1 alone. However Se removed the negative effect of AFB1 on phytohormones, but not AFB1.     

An intensive field trial to assess hazards to birds and mammals from the use of methiocarb as a bird repellent on ripening cherries

A field trial was carried out in Kent, UK, in 1980, to assess the possible hazards to wildlife of methiocarb used as a spray to protect ripening cherries from damage by birds. A broad range of studies was undertaken on a single site subjected to a series of five applications. Ground deposition was measured by analysis of strips of chromatography paper and petri dishes placed between lines of trees. Airborne drift was measured on targets up to 11 m above the ground, and methiocarb residues were measured in samples of cherries. Birds were captured by intensive mist-netting throughout the trial, and breeding success was monitored in nest boxes and natural nest sites. Livetraps were set to catch small mammals in the orchard on five occasions during the trial. Systematic searches for possible casualties were made, resulting in the discovery of 21 birds found dead or incapacitated. Levels of activity of plasma, liver and brain esterases were measured in samples taken from several species, and liver slices from House Sparrows, Starlings and Thrushes were examined histologically for signs of cell damage. Samples of breast muscle tissue from Starlings and House Sparrows were analysed by GLC for residues of methiocarb and its principal breakdown product, methiocarb sulfoxide. Overall, the trial revealed that many birds and mammals were exposed to methiocarb, but its effects were largely transient and sublethal. Even a heavy repeated programme of spray applications did not cause any serious hazard to wildlife populations.