Analysis of various Iowa waters for selected pesticides: atrazine, DDE, and dieldrin-1974.

Atrazine, DDE, and dieldrin were extracted and concentrated from various surface, subsurface, and finished waters using the macroreticular resin method. Organic components in the concentrates from these waters were separated by gas chromatography; the amounts of the three pesticides in the waters ranged from 0.5 to 42,000 parts per trillion by weight. Every major watershed in the State of Iowa revealed some degree of pesticide contamination and seasonal variations were consistent with agricultural runoff models. Atrazine concentrations were highest of the three pesticides, a symptom of its widespread use in the corn belt. DDE also appeared in substantial quantities, providing further evidence of the persistence of DDT and its metabolites. Water from several shallow wells and finished water from many water treatment plants were also contaminated. Current treatment processes do not effectively remove these pesticides.     

Organochlorine pesticides and polychlorinated biphenyls on sediments from a subarctic salt marsh, James Bay, Canada--1976.

Sediment samples were collected from a subarctic salt marsh on James Bay, Ontario in May 1976. Of 15 organochlorine compounds analyzed, trace amounts mainly of p,p-DDE and polychlorinated biphenyls (PCBs) were detected, but could not be quantitated.     

Chlorinated hydrocarbon pesticides and mercury in coastal biota, Puerto Rico and the U.S. Virgin Islands--1972-74.

Baseline levels of mercury and chlorinated hydrocarbons were determined for Caribbean coastal biota as part of the U.S. Environmental Protection Agency estuarine monitoring program. Forty-one percent of the 150 environmental samples taken had significant levels of these compounds. Concentrations of chlorinated hydrocarbons suggest spatial and temporal variations within the plant or animal. In some cases residues in biota could be related to the land-use practices in the sampled watershed.     

Pesticide residues in foodstuffs in Great Britain; organochlorine pesticides,organophosphorus pesticides and fumigant residues in home-produced and imported wheat

Residue levels of organochlorine pesticides, organophosphorus pesticides, fumigants and bromide were determined in home-produced and imported wheat during the period October 1978 to April 1979. A total of 281 samples was analysed of which 133 contained low levels of carbon tetrachloride, 112 contained low levels of gamma-HCH and 26 contained low levels of malathion. One sample contained a residue of carbon tetrachloride, and another a residue of 1,2-dichloroethane, both of which were above the Codex Alimentarius guide-line levels. No other residue approached the proposed Codex Alimentarius maximum residue limits.     

Distribution of organochlorine pesticides in an agricultural environment, Holland Marsh, Ontario--1970-72.

Analaysis of organochlorine pesticides in soil, fish, and human blood samples from Holland Marsh, Ontario, indicates that although total DDT is present in detectable amounts, it does not constitute a hazard to human health and longevity. Among soils tested, residues were highest in surface samples. DDT levels in human blood samples were similar to those in U.S. and British studies.     

Residues of organochlorine pesticides and polychlorinated biphenyls and autopsy data for bald eagles, 1973-74.

Eighty-six bald eagles found sick or dead during 1973-74 in 24 States were analyzed for organochlorine compounds. DDE was detected in all caracasses; polychlorinated biphenyls (PCB's) were found in all but two. Seventy-five carcasses contained TDE and/or dieldrin. Four eagles had possibly lethal levels of dieldrin in the brain. Bald eagles continue to retain high residue levels of organochlorine pollutants. Illegal shooting remained the most common cause of death but accounted for a smaller percentage of the mortalities than in the two previous biennial collections.     

Chlorinated hydrocarbon pesticides and mercury in coastal young-of-the-year finfish, South Carolina and Georgia--1972-74.

Pesticides and heavy metals were monitored in fish collected from 11 estuaries representing all the Atlantic drainage basins in Georgia and South Carolina. Part of the U.S. Environmental Protection Agency National Estuarine Monitoring Program, the semianual survey of young-of-the-year fishes, was conducted from 1972 to 1974. Data are intended to provide an initial base line for residue levels in the fish studied in these waters. Dieldrin was found in 2 percent of the samples, DDT and metabolites were in 33 percent, polychlorinated biphenyls were in 4 percent, and mercury was in 47 percent. Noticeably absent were any measurable residues of toxaphene even though there is a toxaphene manufacturing plant in Brunswick, Ga.     

Residues of pesticides and PCBs in estuarine fish,1972-76--National Pesticide Monitoring Program.

This report summarizes 1524 analyses of juvenile fish collected semiannually in 144 estuaries nationwide from July 1972 through June 1976. Pooled samples of 25 whole fish were screened for 20 common pesticides and polychlorinated biphenyls (PCBs). The three most common residues, DDT, PCBs, and dieldrin, were found in 39, 22, and 5 percent of the samples, respectively. Data indicate that estuarine pollution levels continue to decline.     

双酰胺类农药生物活性、生态毒性及残留行为研究进展

双酰胺类农药是继新烟碱类农药之后备受关注的一类杀虫剂，作用靶标为鱼尼丁受体和γ-氨基丁酸受体，对鳞翅目害虫的防治效果优异。随着双酰胺类农药的广泛应用，其对非靶标生物和水生生态环境产生了潜在威胁，且靶标害虫的抗药性问题也日益凸显。本文综合国内外研究进展，从生物活性、生态毒性、分析方法、环境行为和风险评估5个方面对双酰胺类农药的研究进行了综述，对后续研究方向进行了展望，可为该类农药的精准应用、风险规避和有效管理提供科学参考。     

生物合理性农药与使用技术

综述生物合理性农药的特点、机理及使用技术，为提高农作物的产量和品质，推进无公害农业的发展起到积极的作用。     

Isoboles,a graphic representation of synergism in pesticides

It is possible to give a graphic representation of the effect of two pesticides applied jointly or of the effect of pesticides to which substances have been added. Each of the components is expressed in a coordinate. In the graph a quantitatively defined effect, e.g. a mortality of 50%, is inserted. These values are obtained by interpolation. The line which connects the points is called an isobole afterLoewe & Muischnek (1926) who used it for drugs. With an isobole the effect of different proportions of the components can be evaluated. The various types of isoboles are described and illustrated for some experiments with insecticides, herbicides and fungicides.     

农药在植物中的内吸和传导行为与施药技术研究进展

农药的施用方式和施用效果与其在植物中的内吸和传导行为密切相关.农药在植物表面和内部的内吸和传导行为,不仅与其自身理化性质有关,还受植物种类、生长期、生长条件及施药方式等因素的影响.研究农药在植物体内的内吸和传导行为及其影响因素,对于选择合适的施药技术及提高农药利用率具有重要的指导意义.本文综述了农药在植物体内的内吸和传...     

Monitoring pesticides in agricultural and urban soils of the United States.

Organochlorine pesticides were monitored annually in the major agricultural areas of the United States from 1968 to 1973. Results show that agricultural soils are widely contaminated with low levels of organochlorine residues. Residue concentrations are decreasing as applications of the compounds decrease. Annual monitoring of urban areas since 1969 has demonstrated that urban soils generally have higher pesticide residue concentrations than do agricultural soils in the same locations. High concentrations of mercury, cadmium, and lead have also been observed in urban soils.     

Organic pesticides. XV. Synthesis and insecticidal activity of some compounds containing phosphorus and fluorine

Forty new organofluorine compounds, containing phosphorus, have been synthesised as potential pesticides. The compounds include esters of O,O-dialkyl phosphoramidic acids of the type (RO)₂P(O)NHAr; thioesters of O,O-dialkyl thiophosphoramidic acids of the type (RO)₂P(S)NHAr; esters of O,O-dialkyl phosphonic acid of the type (RO)₂P(O)Ar and esters of O,O-dialkyl thiophosphonic acid (RO)₂P(S)OAr. All the compounds have been screened for their insecticidal activity against adult cockroaches (Periplanata americana) and a few show appreciable activity.