Carbaryl washoff from soybean plants

Both the efficacy and fate of most foliar-applied pesticides may be affected by weather variables, especially rain. A multiple-intensity rainfall simulator was used to determine the effects of rainfall intensity and amount on concentrations of carbaryl (Sevin^® XLS Plus) washed from soybean plants. Two hours after carbaryl was applied at 1.12 kg/ha, 25 mm of rain was applied at intensities of 13.0, 27.4, 53.8, or 105.1 mm/h. About 67% of the carbaryl on the plants was washed off by 25 mm of rain. Rainfall intensity affected carbaryl concentrations in washoff; higher concentrations occurred at lower intensities. Even though the experimental conditions were designed for worst-case conditions, washoff patterns suggested improved carbaryl rainfastness when compared to carbaryl (formulated as a wettable powder) washoff from cotton plants in earlier studies. Rainfall amount had a greater effect on carbaryl concentrations in washoff than rainfall intensity.     

Influence of cypermethrin and fenvalerate on a green alga and three cyanobacteria isolated from soil

The effects of two pyrethroid insecticides, cypermethrin and fenvalerate, on a green alga (Scenedesmus bijugatus) and three species of cyanobacteria (Synechococcus elongatus, Nostoc linckia, and Phormidium tenue), all isolated from a black cotton soil, were studied using either cell number or chlorophyll a as toxicity criterion. All the four species were either unaffected or stimulated at 5 micrograms ml-1. Of the two insecticides, cypermethrin, at 10 to 50 micrograms ml-1, inhibited S. bijugatus while these concentrations stimulated or only slightly inhibited the growth of S. elongatus. There was a significant inhibition in the growth of S. bijugatus and stimulation in S. elongatus with 10 to 50 micrograms ml-1 fenvalerate. The growth of N. linckia was enhanced by both insecticides while P. tenue was significantly affected.     

合肥市德国小蠊对6种常用杀虫剂的抗药性调查测定及防制对策

目的调查合肥市德国小蠊对溴氰菊酯、顺式氯氰菊酯、氰戊菊酯、氯菊酯、胺菊酯和敌敌畏的抗药性现状,为指导防制提供科学依据。方法药膜接触法。结果合肥市德国小蠊对溴氰菊酯、顺式氯氰菊酯、氰戊菊酯、氯菊酯、胺菊酯、敌敌畏6种杀虫剂的KT50分别为9.01、7.20、7.32、15.14、8.41、19.57min,其抗性系数分别是敏感德国小蠊的2.30、1.51、1.20、3.03、2.42、1.80倍。结论合肥市德国小蠊对溴氰菊酯、氯菊酯和胺菊酯产生了抗药性,以氯菊酯抗性为最高。对顺式氯氰菊酯、氰戊菊酯和敌敌畏较为敏感。     

飞机专用杀虫气雾剂的研究

目的：研制一种飞机等交通工具特殊场所专用的杀虫气雾剂；方法：实验室、模拟现场及现场实验；结果：飞机专用杀虫气雾剂在实验室按0．25g／筒-1．0g／筒剂量处理后对蚊、蝇的KT50为1．0min-3．1min，对德国小蠊的KT50为4．8min-7．5min，24h死亡率均达100％。在模拟现场，蚊蝇和蟑螂分别按O．3g／m^3和5．0g/m^2剂量处理后，1h击倒率和24h死亡率均达100％。在现场按模拟现场剂量处理后，对蚊、蝇的KT50分别为10．5min和9．5min，对德国小蠊、美洲大蠊的KT50分别为19．4min和18．Omin，1h击倒率和24h死亡率均达100％；结论：飞机专用杀虫气雾剂具有高效、广谱、低毒、性能稳定等特点，适合于飞机等交通工具特殊场所使用，经有关单位测试与试用取得十分满意的效果，受到用户的欢迎，值得进一步推广应用。     

Neurologic symptoms in licensed private pesticide applicators in the agricultural health study

Exposure to high levels of many pesticides has both acute and long-term neurologic consequences, but little is known about the neurotoxicity of chronic exposure to moderate levels of pesticides. We analyzed cross-sectional data from 18,782 white male licensed private pesticide applicators enrolled in the Agricultural Health Study in 1993-1997. Applicators provided information on lifetime pesticide use and 23 neurologic symptoms typically associated with pesticide intoxication. An indicator of more symptoms (> or = 10 vs. < 10) during the year before enrollment was associated with cumulative lifetime days of insecticide use: odds ratios (95% confidence intervals) were 1.64 (1.36-1.97) for 1-50 days, 1.89 (1.58-2.25) for 51-500 days, and 2.50 (2.00-3.13) for > 500 days, compared with never users. A modest association for fumigants [> 50 days, 1.50 (1.24-1.81)] and weaker relationships for herbicides [> 500 days, 1.32 (0.99-1.75)] and fungicides [> 50 days, 1.23 (1.00-1.50)] were observed. Pesticide use within the year before enrollment was not associated with symptom count. Only associations with insecticides and fumigants persisted when all four pesticide groups were examined simultaneously. Among chemical classes of insecticides, associations were strongest for organophosphates and organochlorines. Associations with cumulative exposure persisted after excluding individuals who had a history of pesticide poisoning or had experienced an event involving high personal pesticide exposure. These results suggest that self-reported neurologic symptoms are associated with cumulative exposure to moderate levels of fumigants and organophosphate and organochlorine insecticides, regardless of recent exposure or history of poisoning.     

Screening of Organophosphate Insecticide Pollution in Water by Using Daphnia magna

A simple and rapid screening method using Daphnia magna Straus (water fleas) on the basis of their immobilization was developed for detecting pesticide pollution. The laboratory testing of the toxicity of 11 organophosphate insecticides to D. magna determined 50% inhibition concentration of mobility at 48 h of exposure (48-h EC₅₀) of 0.19 to 2.6 μg/L. The mobility of D. magna was inhibited in several river and stream waters sampled from May 1995 to February 1998 in Tokyo. Chemical analysis of the waters revealed that they were polluted by sub-ppb or ppb level of organophosphate insecticides. A significant relationship was observed between the immobilization of D. magna and the pollution level of the river and stream waters. The D. magna test could be used as a low-cost preliminary screening method for insecticide pollution.     

Pesticides in the cultivation of carnations in greenhouses: Part II--Relationship between foliar residues and exposures.

The relationship between the levels of dermal and respiratory exposure to pesticides and the amount of pesticide on the leaves of the plants has been studied during cutting of carnations in greenhouses. The study was focused on four pesticides and performed in 18 farms in the Netherlands. Dermal exposure measured by using long-sleeved cotton gloves is strongly related to the amount of dislodgeable foliar residue (DFR). A transfer factor from leaves to hands of approximately 4500 cm2/hr (one-sided projected area) has been calculated. Small differences have been noticed between the different pesticides. Dermal exposure of hands and forearms to pesticides during cutting of carnations can be predicted from measurements of DFR. The DFR was mainly determined by the amount of pesticide remaining from previous applications and the last application rate, not by the application technique (spraying or dusting). The concentrations in the breathing zone after dusting of zineb (dustable powder) and chlorothalonil (wettable powder) were significantly correlated with the dislodgeable foliar residue. The concentrations of thiram did not correlate with DFR. Respiratory exposure results from dispersion of foliar dust containing pesticides.     

Influence of pretreatment with various insecticides on the N-demethylation of dimethylnitrosamine

The effects of various classes of insecticides were studied on the N-demethylation of dimethylnitrosamine (DMN) by mouse liver enzymes. Organochlorine insecticides, represented by lindane, DDT, and endrin, increased the activities of DMN demethylase I and II. The latter enzyme was more susceptible to the inducive action of the tested chlorinated insecticides. On the other hand, the synthetic pyrethroids, fenvalerate and flucythrinate, did not alter the activity of either enzyme. While pretreatment with carbaryl, a carbamate derivative, was without effect, moderate elevation in the activity of both demethylases was observed following administration of carbofuran. Dimethoate, representing organophosphorus compounds, was the only insecticide tested to inhibit the N-demethylation of DMN, with more pronounced effect on DMN demethylase I. Since DMN requires metabolic activation for its hepatotoxic and carcinogenic actions, alterations in the activities of its metabolizing enzymes as a sequela of exposure to certain insecticides may change susceptibility to its toxicity and/or carcinogenicity.     

The efficacy of laundering Captan and Guthion® contaminated fabrics

An evaluation was made of the launder-ability of fabrics contaminated with pesticides. The variables examined were pesticide composition, fabric type, and laundry conditions. Fabric selection enabled the comparison of fabrics commonly worn by the agriculture worker, 100% cotton denim and 100% cotton chambray, and alternate fabrics Gore Tex^® and Tyvek^®, that have been shown to provide greater protection against pesticide penetration. Pesticide selection enabled a comparison between a dicarboximide fungicide and a organophosphorous insecticide.A chamber was designed to provide a laboratory simulation of a field spraying application and was used to contaminate the fabric samples with pesticide residues. The laundry procedure simulated one-home laundry cycle using a heavy duty liquid detergent. Three variations of washwater temperatures were used in the laundry process. Overall, the laundry process removed a relatively high percentage of pesticide residues. However, a significant difference in removal was attributed to pesticide composition, fabric type and wash temperature. Captan residue removal from cotton fabric was lower when compared to synthetic fabrics. Guthion^® residues were more difficult to remove from the fabric Gore Tex^®. An increase in wash temperature resulted in an increase in pesticide removal.     

Insecticide Residues in Soil,Water, and Eggplant Fruits and Farmers’ Health Effects Due to Exposure to Pesticides

Objectives

Eggplant (Solanum melongena L.) is an important vegetable crop that is widely cultivated in the tropical and subtropical areas in Asia. Globally, the top three eggplant producers are China, India, and Egypt. The Philippines has been one of the top 10 eggplant-producing countries based on area planted and crop productivity. This study aims to describe the insecticide residues found in soil, water, and eggplant fruits in eggplant farms in Sta. Maria, Pangasinan.

Methods

The study design is a cross sectional of randomly selected eggplant farms in Sta. Maria, Pangasinan. Soil, water, and eggplant fruits were collected and subjected to gas chromatography (Shimadzu) analysis for multi-pesticide residues.

Results

Farmers from Sta. Maria, Pangasinan were found to be applying a broad spectrum of insecticides on their eggplant crop. Soil samples from 11 (about 42 %) out of the 26 farms tested positive for insecticide residues, six of which from four farms exceeded the acceptable maximum residue limit. These residues were profenofos, triazophos, chlorpyrifos, cypermethrin, and malathion. No insecticide residues were detected from water samples taken from the 26 farms. Cypermethrin and chlorpyrifos were the insecticide residues detected in eggplant fruit samples. A maximum of 20 % of the eggplant samples tested positive for insecticide residues. In the eggplant fruit study, all farmers have been using Prevathon^® for 24 years at a rate of 10 ml/application, and Malathion^® for 25 years at about 16.5 ml/application, respectively equivalent to 0.24 liter-years and 0.413 liter-years of exposure. Similarly, to the findings in the soil and water study, although Brodan^® and Magnum^® were not prevalently applied, the farmers’ liter-years of exposure to these insecticides, and their active ingredients, were highest at about 18.92 and 10.0, respectively. The farmers and farm workers in the soil and water study reported experiencing itchiness of the skin (63.8 %), redness of the eyes (29.3 %), muscle pains (27.6 %), and headaches (27.6 %), as being related to their pesticide exposure.

Conclusion

In summary, a maximum of 20 % of the eggplant samples tested positive for insecticide residues at any one stage of sampling done. The farmers and farm workers also reported of pesticide-related illnesses but none of them sought any medical attention. Intervention to reduce the farmers’ pesticide exposure can focus on the risk factors identified, primarily the toxicity of pesticides used, the unsafe application practices, and the adverse health effects of pesticide exposure.

Electronic supplementary material

The online version of this article (doi:10.1007/s12199-014-0425-3) contains supplementary material, which is available to authorized users.     

Changes in Pest Infestation Levels,Self-Reported Pesticide Use,and Permethrin Exposure during Pregnancy after the 2000–2001 U.S. Environmental Protection Agency Restriction of Organophosphates

Background

Widespread residential pesticide use throughout the United States has resulted in ubiquitous, low-level pesticide exposure. The mix of active pesticide ingredients is changing in response to 2000–2001 regulations restricting use of the organophosphorus insecticides chlorpyrifos and diazinon.

Objectives

We aimed to determine the impact of U.S. Environmental Protection Agency regulations on pest infestation levels, pesticide use, and pesticides measured in indoor air samples. METHODOLOGY: 511 pregnant women from innercity New York were enrolled between 2000 and 2006. Permethrin, a pyrethroid insecticide; piperonyl butoxide (PBO), a pyrethroid synergist; chlorpyrifos; and diazinon were measured in 48-hr prenatal personal air samples. Data on pest infestation and pesticide use were collected via questionnaire.

Results

Eighty-eight percent of women reported using pesticides during pregnancy; 55% reported using higher-exposure pesticide applications (spray cans, pest bombs and/or professional pesticide applicators). Self-reported pest sightings and use of higher-exposure applications increased significantly after the regulations were implemented (p < 0.001). PBO, cis-, and trans-permethrin were detected in 75, 19, and 18% of personal air samples, respectively. Detection frequencies of PBO and cis- and trans-permethrin increased significantly over time (p < 0.05 controlling for potential confounders). Levels and/or detection frequencies of these compounds were significantly higher among mothers reporting use of high exposure pesticide applications (p ≤ 0.05). Chlorpyrifos and diazinon levels decreased significantly over time (p < 0.001).

Conclusion

In this cohort, pest infestations, use of pesticides, and use of permethrin appear to increase after the residential restriction of organophosphorus insecticides. This is one of the first studies to document widespread residential exposure to PBO.     

Effects of fenvalerate exposure on semen quality among occupational workers

Purpose

The purpose of the study was to observe the effects of fenvalerate exposure on the semen quality of occupational workers.

Materials and Methods

Thirty-two male workers who were exposed to fenvalerate and 46 male administrators in the office in the same pesticide factory were selected as the exposure group and internal control group, respectively, and 22 male administrators in a center for disease control served as the external control group. In order to evaluate the exposure levels, the concentration of fenvalerate, toluene and xylene in the ambient air of the work place in these three groups were monitored simultaneously for 3 consecutive days. Moreover, the amount of fenvalerate in individual sampling and dermal contamination were evaluated in the exposure group and external control group. After the semen was collected according to the standard method, the workers' semen qualities were analyzed.

Results

Concentration of fenvalerate in the exposure areas was 21.55×10⁻⁴ mg/m³. The fenvalerate concentration in individual samplings in the exposure areas was 0.11 mg/m³. The dermal contamination for workers in the fenvalerate exposure area was 0.05 mg/m³. Fenvalerate was not detected in individual samplings collected in external areas. Sperm motion parameters through routine semen analysis in the exposure group were decreased significantly, and the abnormality rate of viscidity and coagulation was increased significantly as compared with the internal and the external control groups (p<.05 or p<.01). Furthermore, sperm progression and beat cross frequency (BCF) (4.20±1.68 Hz) in the exposure group were also significantly lower than those in the external control group by computer-assisted sperm motility analysis (CASA) (p<.05).

Conclusion

Occupational exposure to fenvalerate could affect the semen quality of the workers, but the conclusion warrants further complete investigation due to various limitations of the study.     

Assessing Children’s Dietary Pesticide Exposure: Direct Measurement of Pesticide Residues in 24-Hr Duplicate Food Samples

Background

The data presented here are a response to calls for more direct measurements of pesticide residues in foods consumed by children and provide an opportunity to compare direct measures of pesticide residues in foods representing actual consumption with those reported by the U.S. Department of Agriculture Pesticide Data Program.

Objective

We measured pesticide residues in 24-hr duplicate food samples collected from a group of 46 young children participating in the Children’s Pesticide Exposure Study (CPES).

Methods

Parents were instructed to collect 24-hr duplicate food samples of all conventional fruits, vegetables, and fruit juices equal to the quantity consumed by their children, similarly prewashed/prepared, and from the same source or batch. Individual or composite food items were analyzed for organophosphate (OP) and pyrethroid insecticide residues.

Results

We collected a total of 239 24-hr duplicate food samples collected from the 46 CPES children. We found 14% or 5% of those food samples contained at least one OP or pyrethroid insecticide, respectively. We measured a total of 11 OP insecticides, at levels ranging from 1 to 387 ng/g, and three pyrethroid insecticides, at levels ranging from 2 to 1,133 ng/g, in children’s food samples. We found that many of the food items consumed by the CPES children were also on the list of the most contaminated food commodities reported by the Environmental Working Group.

Conclusions

The frequent consumption of food commodities with episodic presence of pesticide residues that are suspected to cause developmental and neurological effects in young children supports the need for further mitigation.     

复配杀虫剂对抗性家蝇杀灭效果的研究

目的：研究杀虫剂的合理复配，提高复配杀虫剂对抗生家蝇的杀灭效果，方法：本实验采用农药登记卫生杀虫剂室药效试验方法和农药登记卫生杀虫剂内药效评价标准。在实验室内对复配卫生杀进行了杀灭抗性家蝇的药效试验研究，结果，单方杀虫剂即使在提高浓度和剂量后，其杀灭效果仍不如复配杀虫剂，结论：复配杀虫剂对抗性的家蝇药效与抗性调查的结果基本一致，单方杀虫剂即在提高浓度和剂量后，可以提高杀虫剂杀灭效果，是家蝇在综合防制中化学灭蝇的一种重要手段，也是延缓及减少抗性发生和发展的有效方法。     

Screening of organophosphate insecticide pollution in water by using Daphnia magna

A simple and rapid screening method using Daphnia magna Straus (water fleas) on the basis of their immobilization was developed for detecting pesticide pollution. The laboratory testing of the toxicity of 11 organophosphate insecticides to D. magna determined 50% inhibition concentration of mobility at 48 h of exposure (48-h EC50) of 0.19 to 2.6 microg/L. The mobility of D. magna was inhibited in several river and stream waters sampled from May 1995 to February 1998 in Tokyo. Chemical analysis of the waters revealed that they were polluted by sub-ppb or ppb level of organophosphate insecticides. A significant relationship was observed between the immobilization of D. magna and the pollution level of the river and stream waters. The D. magna test could be used as a low-cost preliminary screening method for insecticide pollution.     

Pollutant Washoff Characterization of Expressway Runoff in Shanghai

Pollutant washoff loads from an expressway in Shanghai, China were investigated during a 1-year study program. The median washoff load during an rainfall event for total solids, chemical oxygen demand, total nitrogen and total phosphorus were 4,389.8, 2,123.0, 47.6 and 1.6 mg/m², respectively. Through principal factor analysis, three factors that represent the influence of pollutant source availability, rainfall volume and rainfall intensity account for 89% variance of the monitoring data. The result of multiple regression analysis reveals that antecedent dry period significantly influences the washoff load, while peak rainfall intensity and runoff volume may have some influence, which correlates well with the principal factor analysis results.     

Effects of ultra-low volume pyrethrin, malathion, and permethrin on nontarget invertebrates, sentinel mosquitoes, and mosquitofish in seasonally impounded wetlands.

Wildlife managers are concerned that insecticides used to control mosquitoes could suppress invertebrates on which wildlife feed. We assessed whether ultra-low volume (ULV) applications of pyrethrin, permethrin, and malathion for control of adult mosquitoes reduced macroinvertebrate abundance and biomass or killed mosquitofish in seasonal wetlands in California. Pyrethrin was applied over 3 seasonal wetlands on Sutter National Wildlife Refuge (NWR), and malathion or permethrin were each applied over 2 seasonal wetlands on the Colusa NWR. Three control wetlands were used per site. We measured aquatic macroinvertebrate abundance and biomass before and after insecticide application and compared the survival of mosquito larvae held in sentinel cages. At Colusa, we also used mosquitofish as sentinels, caged adult mosquitoes over the wetlands to test for pesticide efficacy and drift, and sampled night-flying insects using ultraviolet light traps. Results showed no detectable reductions in the abundance or biomass of aquatic macroinvertebrates in treated wetlands. Larval mosquitoes showed high survival in all areas. All adult mosquitoes died when caged over wetlands treated with malathion or permethrin, but all survived in controls. All mosquitofish survived. Flying insect abundance decreased after insecticide application in both treated and control wetlands but rebounded in 48 h. Results indicated that ULV applications of these insecticides to control adult mosquitoes are unlikely to have substantial effects on the aquatic insects or fish in seasonal wetlands.     

Toxicological effects of aerial application of monocrotophos

Aerial application of the insecticide Nuvacron 40^® (monocrotophos) had no significant effect on the cholinesterase level of plasma and erythrocytes of cattle, chicken, buffaloes, and human volunteers exposed to the spray. Contamination of canal water with the pesticide was completely eliminated within 24 hr, whereas that in the soil was reduced by 80% in 72 hr. The degradation of insecticide residue in grass was about 90% in seven days and in cotton leaves about 85% for the same period.Contribution No. 473 from CIBA-GEIGY Research Centre, Goregaon East, Bombay 400 063, India     

Acute illnesses associated with insecticides used to control bed bugs--seven states, 2003--2010

The common bed bug, Cimex lectularius, is a wingless, reddish-brown insect that requires blood meals from humans, other mammals, or birds to survive. Bed bugs are not considered to be disease vectors, but they can reduce quality of life by causing anxiety, discomfort, and sleeplessness. Bed bug populations and infestations are increasing in the United States and internationally. Bed bug infestations often are treated with insecticides, but insecticide resistance is a problem, and excessive use of insecticides or use of insecticides contrary to label directions can raise the potential for human toxicity. To assess the frequency of illness from insecticides used to control bed bugs, relevant cases from 2003-2010 were sought from the Sentinel Event Notification System for Occupational Risks (SENSOR)-Pesticides program and the New York City Department of Health and Mental Hygiene (NYC DOHMH). Cases were identified in seven states: California, Florida, Michigan, North Carolina, New York, Texas, and Washington. A total of 111 illnesses associated with bed bug-related insecticide use were identified; although 90 (81%) were low severity, one fatality occurred. Pyrethroids, pyrethrins, or both were implicated in 99 (89%) of the cases, including the fatality. The most common factors contributing to illness were excessive insecticide application, failure to wash or change pesticide-treated bedding, and inadequate notification of pesticide application. Although few cases of illnesses associated with insecticides used to control bed bugs have been reported, recommendations to prevent this problem from escalating include educating the public about effective bed bug management.