甲基化物 评论 甲基化物
James Goodwin1, Federico Holm1
1Center for Progressive Reform, Washington, District of Columbia, USA.
概括
美国环境保护局.
科学领域:
- 环境科学 环境科学
- 监管政策 监管政策
- 职业健康 职业健康 职业健康
背景情况:
- 甲基化物是一种危险的化学物质,具有严重的健康和安全风险,特别是对工人来说.
- 美国环境保护局 (EPA) 提出了一项规则,根据"毒性物质控制法",限制甲基化物使用.
- 成本效益分析 (CBA) 是一种用于评估法规的方法,但它因其方法论而面临批评.
研究的目的:
- 向环保署提交关于拟议的甲基化物规则成本效益分析的批判性意见.
- 突出EPA的CBA中的缺陷,包括低估福利和忽视工人正义.
- 倡导监管分析方面的改革,与目前的拜登政府倡议保持一致.
主要方法:
- 对EPA提出的甲基化物规则的成本效益分析文件的分析.
- 提交正式意见,详细批评环保署的方法.
- 审查对成本效益分析和拟议改革的现有批评.
主要成果:
- 美国环保署对甲基化物规则的CBA采用了一种形式主义的方法,低估了监管效益.
- 分析未能充分考虑关键影响问题,如工人正义.
- 环保署的方法与拜登政府正在进行的成本效益分析改革不一致.
结论:
- 目前对甲基化物限制的成本效益分析有缺陷,需要进行重大修订.
- 监管影响评估必须包括超越纯粹经济指标的更广泛的考虑,包括社会公平.
- 环保署应采用最新的CBA方法,反映当前的最佳实践和行政改革.
相关概念视频
01:27Radical Substitution: Halogenation of Alkanes and Alkyl Substituents
8.3K
In the presence of heat or light, alkanes react with molecular halogens to form alkyl halides by a substitution reaction called radical halogenation. This reaction has three steps: initiation, propagation, and termination, as seen in the radical chlorination of methane to produce methyl chloride.
In the initiation step of the reaction, the chlorine molecule undergoes homolytic cleavage in the presence of light or heat, forming two highly reactive chlorine radicals. Propagation occurs in two...
In the initiation step of the reaction, the chlorine molecule undergoes homolytic cleavage in the presence of light or heat, forming two highly reactive chlorine radicals. Propagation occurs in two...
8.3K
02:46Halogenation of Alkenes
15.8K
Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
15.8K
01:33Carboxylic Acids to Methylesters: Alkylation using Diazomethane
2.2K
Carboxylic acids react with diazomethane in an ether solvent via alkylation at the carboxylate oxygen atom to give methyl esters of the corresponding acid with excellent yields.
2.2K
02:45Alkyl Halides
16.9K
Structural Properties
Alkyl halides are halogen-substituted alkanes wherein one or more hydrogen atoms of an alkane is replaced by a halogen atom such as fluorine, chlorine, bromine, or iodine. The carbon atom in an alkyl halide is bonded to the halogen atom, which is sp3-hybridized and exhibits a tetrahedral shape.
Unlike alkyl halides, compounds in which a halogen atom is bonded to an sp2 -hybridized carbon atom of a carbon-carbon double bond (C=C) are called vinyl halides. Whereas aryl...
Alkyl halides are halogen-substituted alkanes wherein one or more hydrogen atoms of an alkane is replaced by a halogen atom such as fluorine, chlorine, bromine, or iodine. The carbon atom in an alkyl halide is bonded to the halogen atom, which is sp3-hybridized and exhibits a tetrahedral shape.
Unlike alkyl halides, compounds in which a halogen atom is bonded to an sp2 -hybridized carbon atom of a carbon-carbon double bond (C=C) are called vinyl halides. Whereas aryl...
16.9K
01:14Acid Halides to Ketones: Gilman Reagent
3.0K
Lithium dialkyl cuprate, also known as Gilman reagents, selectively reduces acid halides to ketones. The acid chloride is treated with Gilman reagent at −78 °C in the presence of ether solution to produce a ketone in good yield.
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
3.0K
02:14SN2 Reaction: Kinetics
8.5K
Kinetic Studies and Significance
In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
8.5K