BARIUM SULFATE

The inorganic sulfates (See Figure 1) are salts of sulfuric acid. Except for the ammonium salts, these ingredients are mineral salts readily found in nature (but may also be easily synthesized).3 While most of these ingredients are readily soluble in water, barium sulfate is virtually insoluble, and almost no absorption occurs even when passed through the human digestive tract (making it a non-toxic, imaging contrast agent).4 Figure 1. Inorganic Sulfates – wherein “M” is an ammonium or metal cation The formulas of the inorganic sulfates reviewed in this safety assessment are included in Figure 2.5 Table 1 contains the definitions and functions of these cosmetic ingredients. Physical and Chemical Properties Properties of inorganic sulfates reviewed in this safety assessment are included in Table 2.6 Method of Manufacture The inorganic sulfates are typically manufactured by mining of natural minerals (as many inorganic sulfates occur naturally in hydrated form) or by reaction of available ore or inorganic oxides, hydroxides, or carbonates, with sulfuric acid.3 These methods produce hydrated inorganic sulfates. To produce the anhydrous salts, an additional step of dehydration (e.g., by heating and reduced pressure) must occur. For example, hydrated magnesium sulfate can be mined as kieserite or epsomite (Epsom salts), or it can be prepared by dissolving magnesium oxide, magnesium hydroxide, or magnesium carbonate in sulfuric acid. Heating of this hydrate reversibly drives off water and produces anhydrous magnesium sulfate (a potent desiccant).  Distributed for Comment Only -- Do Not Cite or Quote Composition/Impurities Barium Sulfate … [kırpıldı — bölüm toplam 212011 karakter]

Definition and Structure Barium sulfate (CAS No. 7727-43-7) is the inorganic salt that conforms to the formula that is included in Figure 2 below.1 It is the barium salt of sulfuric acid. BaSO 4 Figure 2. Formula for Barium Sulfate Physical and Chemical Properties Barium sulfate, available in the form of polymorphous crystals, has a molecular weight of 233.39, and is soluble in sulfuric acid, but insoluble in water.2 Method of Manufacture Barium sulfate may be produced by treating a solution of barium salt with sodium sulfate (salt cake).3 Composition/Impurities Barytes is the naturally occurring rock form of BaSO 4 .4 A study was performed to characterize the mineralogical forms of barium and the trace heavy metal impurities in commercial barytes of different origins using electron probe microanalysis (EPMA), X-ray diffraction (XRD), and inductively coupled plasma mass spectrometry (ICP-MS). Qualitative EPMA results indicated the presence of different minerals in commercial barytes, including barite (BaSO 4 ), barium feldspar, galena (PbS), pyrite (FeS 2 ), sphalerite (ZnS), quartz (SiO 2 ), and silicates. Quantitative EPMA confirmed that the barite crystals in the barytes contain some strontium and a little calcium, whereas, trace heavy metals occur in the associated minerals. Analysis of aqua regia extracts of barytes samples by ICP-MS has indicated the presence of a large number of elements in the associated minerals. Arsenic, copper, and zinc concentrations correlate closely in all 10 samples. Chromium has been detected in commercial samples of pharmaceutical grade barium sulfate at concentrations ranging from 0.45 to 1.06 µg/g.5 … [kırpıldı — bölüm toplam 18606 karakter]

CIR tentative (2014): The CIR Expert Panel concluded that barium sulfate is safe in the present practices of use and concentration in cosmetics, when formulated to be non-irritating.

EPA ToxValDB skin/eye data — endpoint: eye irritation: in vivo, classification: Studies Indicate No Significant Irritation, species: rabbit, study: eye irritation, guideline: OECD Guideline 405 (Acute Eye Irritation / Corrosion) , 2002-04-24 according to, year: 2010. Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxValDB skin/eye data — endpoint: Skin Sensitization, classification: Classification not possible. Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxValDB skin/eye data — endpoint: Eye Irritation, classification: Classification not possible. Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.

EPA ToxValDB skin/eye data — endpoint: Skin Irritation, classification: Classification not possible. Caveat: this is an aggregated record; dose, species and route of exposure must be considered together.