Dermal Absorption of 2,4-D Is Underestimated EPA Used an Outdated Study to Estimate Dermal Absorption of 2,4-D
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Relative Tolerance of Peanuts to Alachlor and Metolachlor' Materials
Relative Tolerance of Peanuts to Alachlor and Metolachlor' Glenn Wehtje*, John W. Wilcut, T. Vint Hicks2. and John McGuire3 ABSTRACT vealed that peas were most sensitive across all the sub- Field studies were conducted during 1984, 1985, and 1987 to evaluate weed control and the relative tolerance of peanuts stituted amide herbicides when the application was (Arachis hypogaea) to alachlor and metolachlor when applied at made 2 days after planting. This time of application cor- rates from 2.2 to 13.4 kg adha. Both single and split responded to shoot emergence, which is considered to preemergence, and postemergence applications were in- be the most sensitive portion of the seedling, through cluded. In 1984 and 1985, neither herbicide adversely affected the surface of the treated soil. Later applications re- yields compared to a hand-weeded control. In 1987, metolachlor at a rate of 9.0 kgha and alachlor at 13.4 k&a re- sulted in progressively less injury, indicating that the duced yields. Across all years, at least a two-fold safety factor foliar portion of the developing pea was relatively toler- existed between the maximum registered rate and the rate ant once emerged. Field studies indicated injury was necessary for peanut injury. Occurrence of injury appears to be markedly influenced by rainfall soon after planting. related to rainfall. Metolachlor was slightly more mobile than alachlor in soil chromatography trials, which may be a factor in Putnam and Rice (7) evaluated the factors associated its slightly greater propensity to be injurious under certain with alachlor injury on snap beans (Phaseolus vulgaris conditions of extensive leaching and/or slow peanut L.). -
2,4-Dichlorophenoxyacetic Acid
2,4-Dichlorophenoxyacetic acid 2,4-Dichlorophenoxyacetic acid IUPAC (2,4-dichlorophenoxy)acetic acid name 2,4-D Other hedonal names trinoxol Identifiers CAS [94-75-7] number SMILES OC(COC1=CC=C(Cl)C=C1Cl)=O ChemSpider 1441 ID Properties Molecular C H Cl O formula 8 6 2 3 Molar mass 221.04 g mol−1 Appearance white to yellow powder Melting point 140.5 °C (413.5 K) Boiling 160 °C (0.4 mm Hg) point Solubility in 900 mg/L (25 °C) water Related compounds Related 2,4,5-T, Dichlorprop compounds Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) 2,4-Dichlorophenoxyacetic acid (2,4-D) is a common systemic herbicide used in the control of broadleaf weeds. It is the most widely used herbicide in the world, and the third most commonly used in North America.[1] 2,4-D is also an important synthetic auxin, often used in laboratories for plant research and as a supplement in plant cell culture media such as MS medium. History 2,4-D was developed during World War II by a British team at Rothamsted Experimental Station, under the leadership of Judah Hirsch Quastel, aiming to increase crop yields for a nation at war.[citation needed] When it was commercially released in 1946, it became the first successful selective herbicide and allowed for greatly enhanced weed control in wheat, maize (corn), rice, and similar cereal grass crop, because it only kills dicots, leaving behind monocots. Mechanism of herbicide action 2,4-D is a synthetic auxin, which is a class of plant growth regulators. -
Response of Multiple Herbicide Resistant Strain of Diazotrophic Cyanobacterium, Anabaena Variabilis , Exposed to Atrazine and DCMU
Indian Journal of Experimental Biology Vol. 49, April 2011, pp.298-303 Response of multiple herbicide resistant strain of diazotrophic cyanobacterium, Anabaena variabilis , exposed to atrazine and DCMU Surendra Singh, Pallavi Datta * & Archna Tirkey Algal Biotechnology Laboratory, Department of Biological Sciences, Rani Durgavati University, Jabalpur 482 001, India Received 1 June 2010; revised 24 January 2011 Effect of two photosynthetic inhibitor herbicides, atrazine (both purified and formulated) and [3-(3,4-dichlorophenyl)- 1,1-dimethyl urea] (DCMU), on the growth, macromolecular contents, heterocyst frequency, photosynthetic O 2 evolution and dark O 2 uptake of wild type and multiple herbicide resistant (MHR) strain of diazotrophic cyanobacterium A. variabilis was studied. Cyanobacterial strains showed gradual inhibition in growth with increasing dosage of herbicides. Both wild type and MHR strain tolerated < 6.0 mg L -1 of atrazine (purified), < 2.0 mg L -1 of atrazine (formulated) and < 0.4 mg L -1 of DCMU indicating similar level of herbicide tolerance. Atrazine (pure) (8.0 mg L -1) and 4.0 mg L -1 of atrazine (formulated) were growth inhibitory concentrations (lethal) for both wild type and MHR strain indicating formulated atrazine was more toxic than the purified form. Comparatively lower concentrations of DCMU were found to be lethal for wild type and MHR strain, respectively. Thus, between the two herbicides tested DCMU was more growth toxic than atrazine. At sublethal dosages of herbicides, photosynthetic O 2 evolution showed highest inhibition followed by chlorophyll a, phycobhiliproteins and heterocyst differentiation as compared to carotenoid, protein and respiratory O 2 uptake. Keyword s: Atrazine, Cyanobacteria, DCMU, Herbicides, Mutants, Photosynthesis In modern agriculture weed control by herbicides is a tolerate or resist toxic actions of various rice field common practice to increase in crop productivity 1. -
Greenhouse and Field Evaluation of Isoxaflutole for Weed Control In
www.nature.com/scientificreports OPEN Greenhouse and field evaluation of isoxaflutole for weed control in maize in China Received: 27 June 2017 Ning Zhao, Lan Zuo, Wei Li, Wenlei Guo, Weitang Liu & Jinxin Wang Accepted: 18 September 2017 Greenhouse and field studies were conducted to provide a reference for pre-emergence (PRE) Published: xx xx xxxx application of isoxaflutole on maize in China. In greenhouse study, the isoxaflutole PRE application at 30 g active ingredient (a.i.) ha−1 could effectively control large numbers of weeds, especially some large-seeded broadleaves, tested in this study. The tolerance results indicated 21 maize hybrids showed different responses to isoxaflutole under greenhouse conditions. In 2015 and 2016, field experiments were conducted to determine and compare the weed control efficacy and safety to Zhengdan 958 maize with 6 herbicide treatments. In both years, isoxaflutole PRE at 100 to 250 g a.i. ha−1 was sufficient to provide satisfactory full-season control of the dominant common broadleaf and grass weeds in the field. Temporary injury to maize was observed with isoxaflutole treatments of 125, 150, and 250 g a.i. ha−1 in both years, but plants recovered within 4 to 6 wk. To maximize maize yield and provide satisfactory weed control, a range of 100 to 150 g a.i. ha−1 of isoxaflutole is recommended, depending on the soil characteristics, weather, and weed species present at the experimental site. Based on the results, isoxaflutole PRE has good potential for weed control in maize in China. Maize was planted on more hectares than any other crops in China from 2010 to 2014, with an average of 35 million ha planted per year and yield averaging 5,779 kg per ha per year1. -
Exposure to Herbicides in House Dust and Risk of Childhood Acute Lymphoblastic Leukemia
Journal of Exposure Science and Environmental Epidemiology (2013) 23, 363–370 & 2013 Nature America, Inc. All rights reserved 1559-0631/13 www.nature.com/jes ORIGINAL ARTICLE Exposure to herbicides in house dust and risk of childhood acute lymphoblastic leukemia Catherine Metayer1, Joanne S. Colt2, Patricia A. Buffler1, Helen D. Reed3, Steve Selvin1, Vonda Crouse4 and Mary H. Ward2 We examine the association between exposure to herbicides and childhood acute lymphoblastic leukemia (ALL). Dust samples were collected from homes of 269 ALL cases and 333 healthy controls (o8 years of age at diagnosis/reference date and residing in same home since diagnosis/reference date) in California, using a high-volume surface sampler or household vacuum bags. Amounts of agricultural or professional herbicides (alachlor, metolachlor, bromoxynil, bromoxynil octanoate, pebulate, butylate, prometryn, simazine, ethalfluralin, and pendimethalin) and residential herbicides (cyanazine, trifluralin, 2-methyl-4- chlorophenoxyacetic acid (MCPA), mecoprop, 2,4-dichlorophenoxyacetic acid (2,4-D), chlorthal, and dicamba) were measured. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by logistic regression. Models included the herbicide of interest, age, sex, race/ethnicity, household income, year and season of dust sampling, neighborhood type, and residence type. The risk of childhood ALL was associated with dust levels of chlorthal; compared to homes with no detections, ORs for the first, second, and third tertiles were 1.49 (95% CI: 0.82–2.72), 1.49 (95% CI: 0.83–2.67), and 1.57 (95% CI: 0.90–2.73), respectively (P-value for linear trend ¼ 0.05). The magnitude of this association appeared to be higher in the presence of alachlor. -
Agricultural Herbicide Use and Risk of Lymphoma and Soft-Tissue Sarcoma Shelia K
Agricultural Herbicide Use and Risk of Lymphoma and Soft-Tissue Sarcoma Shelia K. Hoar, ScD; Aaron Blair, PhD; Frederick F. Holmes, MD; Cathy D. Boysen; Robert J. Robel, PhD; Robert Hoover, MD; Joseph F. Fraumeni, Jr, MD A population-based case-control study of soft-tissue sarcoma (STS), Hodgkin's agents for leather and textiles, and disease (HD), and non-Hodgkin's lymphoma (NHL) in Kansas found farm medications.1 For these reasons, a pop¬ herbicide use to be associated with NHL (odds ratio [OR], 1.6; 95% confidence ulation-based case-control study was interval [CI], 0.9, 2.6). Relative risk of NHL increased significantly with number conducted to clarify whether agricul¬ of of herbicide and Men to herbicides tural use of herbicides and insecticides days exposure per year latency. exposed and NHL in than 20 had sixfold increased risk of NHL 95% affects risk of STS, HD, more days per year a (OR, 6.0; the United States. CI, 1.9, 19.5) relative to nonfarmers. Frequent users who mixed or applied the herbicides themselves had an OR of 8.0 (95% CI, 2.3, 27.9) for NHL. Excesses METHODS were associated with use of phenoxyacetic acid herbicides, specifically Kansas, a major wheat-producing acid. Neither STS nor HD was associated with 2,4-dichlorophenoxyacetic state, was chosen as the location for pesticide exposure. This study confirms the reports from Sweden and several the study, since herbicides have been US NHL states that is associated with farm herbicide use, especially used more frequently than other pesti¬ phenoxyacetic acids. -
Multi-Residue Method I for Agricultural Chemicals by LC-MS (Agricultural Products)
Multi-residue Method I for Agricultural Chemicals by LC-MS (Agricultural Products) 1. Analytes See Table 2 or 3. 2. Instruments Liquid chromatograph-mass spectrometer (LC-MS) Liquid chromatograph-tandem mass spectrometer (LC-MS/MS) 3. Reagents Use the reagents listed in Section 3 of the General Rules except for the following. 0.5 mol/L Phosphate buffer (pH 7.0): Weigh 52.7 g of dipotassium hydrogenphosphate (K2HPO4) and 30.2 g of potassium dihydrogenphosphate (KH2PO4), dissolve in about 500 mL of water, adjust the pH to 7.0 with 1 mol/L sodium hydroxide or 1 mol/L hydrochloric acid, and add water to make a 1 L solution. Reference standards of agricultural chemicals: Reference standards of known purities for each agricultural chemical. 4. Procedure 1) Extraction i) Grains, beans, nuts and seeds Add 20 mL of water to 10.0 g of sample and let stand for 15 minutes. Add 50 mL of acetonitrile, homogenize, and filter with suction. Add 20 mL of acetonitrile to the residue on the filter paper, homogenize, and filter with suction. Combine the resulting filtrates, and add acetonitrile to make exactly 100 mL. Take a 20 mL aliquot of the extract, add 10 g of sodium chloride and 20 mL of 0.5 mol/L phosphate buffer (pH 7.0), and shake for 10 minutes. Let stand, and discard the separated aqueous layer. Add 10 mL of acetonitrile to an octadecylsilanized silica gel cartridge (1,000 mg) and discard the effluent. Transfer the acetonitrile layer to the cartridge, elute with 2 mL of acetonitrile, collect the total eluates, dehydrate with anhydrous sodium sulfate, and filter out the anhydrous sodium sulfate. -
INDEX to PESTICIDE TYPES and FAMILIES and PART 180 TOLERANCE INFORMATION of PESTICIDE CHEMICALS in FOOD and FEED COMMODITIES
US Environmental Protection Agency Office of Pesticide Programs INDEX to PESTICIDE TYPES and FAMILIES and PART 180 TOLERANCE INFORMATION of PESTICIDE CHEMICALS in FOOD and FEED COMMODITIES Note: Pesticide tolerance information is updated in the Code of Federal Regulations on a weekly basis. EPA plans to update these indexes biannually. These indexes are current as of the date indicated in the pdf file. For the latest information on pesticide tolerances, please check the electronic Code of Federal Regulations (eCFR) at http://www.access.gpo.gov/nara/cfr/waisidx_07/40cfrv23_07.html 1 40 CFR Type Family Common name CAS Number PC code 180.163 Acaricide bridged diphenyl Dicofol (1,1-Bis(chlorophenyl)-2,2,2-trichloroethanol) 115-32-2 10501 180.198 Acaricide phosphonate Trichlorfon 52-68-6 57901 180.259 Acaricide sulfite ester Propargite 2312-35-8 97601 180.446 Acaricide tetrazine Clofentezine 74115-24-5 125501 180.448 Acaricide thiazolidine Hexythiazox 78587-05-0 128849 180.517 Acaricide phenylpyrazole Fipronil 120068-37-3 129121 180.566 Acaricide pyrazole Fenpyroximate 134098-61-6 129131 180.572 Acaricide carbazate Bifenazate 149877-41-8 586 180.593 Acaricide unclassified Etoxazole 153233-91-1 107091 180.599 Acaricide unclassified Acequinocyl 57960-19-7 6329 180.341 Acaricide, fungicide dinitrophenol Dinocap (2, 4-Dinitro-6-octylphenyl crotonate and 2,6-dinitro-4- 39300-45-3 36001 octylphenyl crotonate} 180.111 Acaricide, insecticide organophosphorus Malathion 121-75-5 57701 180.182 Acaricide, insecticide cyclodiene Endosulfan 115-29-7 79401 -
Toxicological Profile for Glyphosate Were
A f Toxicological Profile for Glyphosate August 2020 GLYPHOSATE II DISCLAIMER Use of trade names is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry, the Public Health Service, or the U.S. Department of Health and Human Services. GLYPHOSATE III FOREWORD This toxicological profile is prepared in accordance with guidelines developed by the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA). The original guidelines were published in the Federal Register on April 17, 1987. Each profile will be revised and republished as necessary. The ATSDR toxicological profile succinctly characterizes the toxicologic and adverse health effects information for these toxic substances described therein. Each peer-reviewed profile identifies and reviews the key literature that describes a substance's toxicologic properties. Other pertinent literature is also presented, but is described in less detail than the key studies. The profile is not intended to be an exhaustive document; however, more comprehensive sources of specialty information are referenced. The focus of the profiles is on health and toxicologic information; therefore, each toxicological profile begins with a relevance to public health discussion which would allow a public health professional to make a real-time determination of whether the presence of a particular substance in the environment poses a potential threat to human health. The adequacy of information to determine a substance's -
Decision Guidance Documents
OPERATION OF THE PRIOR INFORMED CONSENT PROCEDURE FOR BANNED OR SEVERELY RESTRICTED CHEMICALS IN INTERNATIONAL TRADE DECISION GUIDANCE DOCUMENTS Dinoseb and its salts and esters JOINT FAO/UNEP PROGRAMME FOR THE OPERATION OF PRIOR INFORMED CONSENT United Nations Environment Programme UNEP Food and Agriculture Organization of the United Nations OPERATION OF THE PRIOR INFORMED CONSENT PROCEDURE FOR BANNED OR SEVERELY RESTRICTED CHEMICALS IN INTERNATIONAL TRADE DECISION GUIDANCE DOCUMENTS Dinoseb and its salts and esters JOINT FAO/UNEP PROGRAMME FOR THE OPERATION OF PRIOR INFORMED CONSENT Food and Agriculture Organization of the United Nations United Nations Environment Programme Rome - Geneva 1991 DISCLAIMER The inclusion of these chemicals in the Prior Informed Consent Procedure is based on reports of control action submitted to the United Nations Environment Programme (UNEP) by participating countries, and which are presently listed in the UNEP-International Register of Potentially Toxic Chemicals (IRPTC) database on Prior Informed Consent. While recognizing that these reports from countries are subject to confirmation, the FAO/UNEP Joint Working Group of Experts on Prior Informed Consent have recommended that these chemical be included in the Procedure. The status of these chemicals will be reconsidered on the basis of such new notifications as may be made by participating countries from time to time. The use of trade names in this document is primarily intended to facilitate the correct identification of the chemical. It is not intended to imply approval or disapproval of any particular company. As it is not possible to include all trade names presently in use, only a number of commonly used and published trade names have been included here. -
(12) United States Patent (10) Patent No.: US 7,943,644 B2 Uhr Et Al
USOO794364.4B2 (12) United States Patent (10) Patent No.: US 7,943,644 B2 Uhr et al. (45) Date of Patent: May 17, 2011 (54) STABILIZATION OF IODINE-CONTAINING (56) References Cited BOCDES BY MEANS OF SPECIAL AZOLE COMPOUNDS U.S. PATENT DOCUMENTS 2,739,922 A * 3/1956 Shelanski ..................... 524,548 (75) Inventors: Hermann Uhr, Leverkusen (DE); 4,276,211 A 6/1981 Singer et al. ... 260/29.6 MN Johannes Kaulen, Odenthal (DE); 4.297.258 A 10/1981 Long, Jr. .............. 260f29.6 MN Thomas Jaetsch, Köln (DE); Peter 4,552,885. A 1 1/1985 Gabriele et al. .............. 514/316 Spetmann, Leverkusen (DE) 5,051,256 A * 9/1991 Barnes ........... ... 424/402 6,143,204. A 1 1/2000 Lutz et al. ...... ... 252/384 rsr rr 6.353,021 B1 3/2002 Gaglani et al. ... 514,478 (73) Assignee: NNESS putschland GmbH, 6,472,424 B1 10/2002 Gaglani et al. ... 514,478 everkusen (DE) 6,946,427 B2* 9/2005 Lutz et al. ...... ... 504,140 c - 2006/00 13833 A1 1/2006 Bartko ........... ... 424/400 (*) Notice: Subject to any disclaimer, the term of this 2007/0128246 A1* 6/2007 Hossainy et al. ............. 424/423 patent is extended or adjusted under 35 U.S.C. 154(b) by 18 days. FOREIGN PATENT DOCUMENTS WO 98.22543 5, 1998 (21) Appl. No.: 12/281,163 WO 99.291.76 6, 1999 WO OOf 16628 3, 2000 (22) PCT Filed: Feb. 21, 2007 WO 2007 O28527 3, 2007 (86). PCT No.: PCT/EP2007/001480 OTHER PUBLICATIONS S371 (c)(1), Nomiya, Kenji, et al. -
Alachlor in Drinking-Water
WHO/SDE/WSH/03.04/31 English only Alachlor in Drinking-water Background document for development of WHO Guidelines for Drinking-water Quality ______________________________ Originally published in Guidelines for drinking-water quality, 2nd ed. Vol.2. Health criteria and other supporting information. World Health Organization, Geneva, 1996. © World Health Organization 2003 All rights reserved. Publications of the World Health Organization can be obtained from Marketing and Dissemination, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email: [email protected]). Requests for permission to reproduce or translate WHO publications – whether for sale or for noncommercial distribution – should be addressed to Publications, at the above address (fax: +41 22 791 4806; email: [email protected]). The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. The World Health Organization does not warrant that the information contained in this publication is complete and correct and shall not be liable for any damages incurred as a result of its use.