Determination of methanethiol at parts-per-million air concentrations by gas chromatography

Organic sulfur compounds are sulfur‐based chemicals that are used in a variety of industrial applications such as manufacturing, agriculture, the environment, and pharmaceuticals. The compounds included in this chapter have been grouped according to chemical classes and were selected based on their common industrial uses and commercial importance, with a major focus on mercaptans (also called thiols or sulfhydryls). The other classes include sulfides, disulfides, chemicals with both sulfur and oxygen atoms (sulfoxides, sulfones, sulfonates, and sulfonyl chlorides), miscellaneous groups (thiophenes and benzothiazoles), and sulfur mustards. Industrial uses for these compounds include intermediates in chemical synthesis, gas odorants (especially C 2 to C 4 mercaptans), chelating or complexing agents, catalysts, solvents, and accelerators or components of synthetic rubber products. The sulfonates are used in the production of anionic detergents, surfactants, and wetting agents, and in some cases, as lubricant additives. The only use for the very toxic sulfur mustards is for chemical warfare. For many of these compounds, there is limited toxicological data in the open literature; however, the majority of data is available from unpublished industry‐sponsored documents that are referred to in the text so that this information is available to the scientific and industrial communities interested in learning more about the hazards associated with these classes of compounds.

Organic Sulfur Compounds

Arrieta,

Régnier

2023

Organic Sulfur Compounds

Shertzer¹

2000

Sulfur appears in group VI of the periodic table, just below oxygen. Similar to other second row elements, sulfur is more versatile as a reaction center than first‐row counterparts. Both oxygen and sulfur tend to alter the reactivity of an adjacent carbon atom, but sulfur itself is more reactive than oxygen toward nucleophilic, electrophilic, and radical reagents. Therefore, chemical reactions that involve organic sulfur compounds tend to occur directly at sulfur. Organic sulfur compounds are economically important in every type of industry, including manufacturing, agriculture, the environment, and pharmaceuticals. The chemicals included in this chapter were selected on the basis of their common industrial uses and commercial importance, although some compounds have multiple types of use. The chemicals have been grouped according to chemical classes. The major focus is on mercaptans (also called thiols or sulfhydryls), and sulfides, chemicals with both sulfur and oxygen atoms (sulfoxides, sulfones, sulfonates, and sulfonyl chlorides), and a miscellaneous group (thiophenes and benzothiazoles). There is a paucity of toxicological data in the open literature for many of these compounds, and a wealth of scientific information that is contained in unpublished industrial documents. Many of these unpublished reports have been referred to in previous editions of Patty's. So that the important information contained in these reports is not lost to the scientific and industrial communities, they have been maintained in the current chapter and referred to in the text, rather than in the list of references. The basic chemical and physical properties of industrially important organic sulfur compounds are summarized. The distinctive odor associated with sulfur is particularly important for many of these compounds. Often thought of as pleasant at low concentrations, higher subtoxic concentrations are often extremely offensive. The thiol containing amino acid cysteine is important in maintaining proper protein structure via disulfide bonds between two cysteine residues. In addition, cysteine forms the reactive moiety of the intracellular antioxidant glutathione that helps maintain the highly reduced state of cells and protects cells from potentially toxic electrophiles and radicals that may originate from metabolism or from foreign sources (xenobiotics). Mercaptans, it has long been known, react with several heavy metals, including mercury. The formation of insoluble mercury complexes is characteristic of this class of compounds and is the source of the name mercaptan ( mercurium captans , capturing mercury). Although not in current use, the dithiol 2,3‐dimercapto‐1‐propanol (BAL, dimercaprol, British anti‐Lewisite CAS Number [ 59-52-9 ]) was developed to protect against arsenical war gases (including Lewisite) and has been used as an antidote for exposure to arsenic, mercury, and other heavy metals. Interestingly, mercaptans such as the intracellular antioxidant glutathione activate the environmentally and occupationally important heavy metal Cr 6+ and also the economically important solvent methylene chloride to genotoxic products.

Organic Sulfur Compounds

Shertzer¹

2012

Sulfur‐containing materials are widespread in the environment and are essential for survival of mammals and other species. Methyl and ethyl mercaptans are extremely important in fundamental biological processes such as a source of sulfur or carbon fragments in mammalian biosynthetic pathways. Sulfur‐containing chemicals have toxic properties which may be attributed generally to their chemical, physical and biochemical properties, including their ability to react with heavy metals. The chemicals have been grouped according to chemical classes, with a major focus on mercaptans (also called thiols or sulfhydryls), sulfides, chemicals with both sulfur and oxygen atoms (sulfoxides, sulfones, sulfonates, and sulfonyl chlorides), miscellaneous groups (thiophenes and benzothiazoles), and sulfur mustards. The physical and chemical properties, exposure assessment, regulations and standards have been reviewed extensively.