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67-509: Talc , or talcum , is a clay mineral composed of hydrated magnesium silicate , with the chemical formula Mg 3 Si 4 O 10 (OH) 2 . Talc in powdered form, often combined with corn starch , is used as baby powder . This mineral is used as a thickening agent and lubricant . It is an ingredient in ceramics , paints , and roofing material . It is a main ingredient in many cosmetics . It occurs as foliated to fibrous masses, and in an exceptionally rare crystal form. It has

134-446: A St. Louis jury awarded $ 72 million to the family of an Alabama woman who died from ovarian cancer . The family claimed that the use of talcum powder was responsible for her cancer. In May 2016, a South Dakota woman was awarded $ 55 million as the result of another lawsuit against J&J. The woman had used Johnson & Johnson's Baby Powder for more than 35 years before being diagnosed with ovarian cancer in 2011. In October 2016,

201-508: A glidant . In medicine, talc is used as a pleurodesis agent to prevent recurrent pleural effusion or pneumothorax . In the European Union , the additive number is E553b . Talc may be used in the processing of white rice as a buffing agent in the polishing stage. Due to its low shear strength, talc is one of the oldest known solid lubricants. Also, limited use is made of talc as a friction-reducing additive in lubricating oils. Talc

268-479: A St. Louis jury awarded $ 70.1 million to a Californian woman with ovarian cancer who had used Johnson's Baby Powder for 45 years. In August 2017, a Los Angeles jury awarded $ 417 million to a Californian woman, Eva Echeverria, who developed ovarian cancer as a "proximate result of the unreasonably dangerous and defective nature of talcum powder", her lawsuit against Johnson & Johnson stated. On 20 October 2017, Los Angeles Superior Court judge Maren Nelson dismissed

335-511: A court in St. Louis awarded a $ 4.7bn claim ($ 4.14bn in punitive damages and $ 550m in compensatory damages) against J&J to 22 claimant women, concluding that the company had suppressed evidence of asbestos in its products for more than four decades. At least 1,200 to 2,000 other talcum powder-related lawsuits were pending as of 2016. In 2020 J&J stopped sales of its talcum-based baby powder, which it had been selling for 130 years. J&J created

402-588: A general term for different types of fibrous silicate minerals, desirable in construction for their heat resistant properties. There are six varieties of asbestos; the most common variety in manufacturing, white asbestos , is in the serpentine family. Serpentine minerals are sheet silicates ; although not in the serpentine family, talc is also a sheet silicate, with two sheets connected by magnesium cations. The frequent co-location of talc deposits with asbestos may result in contamination of mined talc with white asbestos, which poses serious health risks when dispersed into

469-479: A hexagonal array in two dimensions. The fourth oxygen ion is not shared with another tetrahedron and all of the tetrahedra "point" in the same direction; i.e. all of the unshared oxygen ions are on the same side of the sheet. These unshared oxygen ions are called apical oxygen ions. In clays, the tetrahedral sheets are always bonded to octahedral sheets formed from small cations, such as aluminum or magnesium, and coordinated by six oxygen atoms. The unshared vertex from

536-409: A layered CdI 2 -like structure with hydrogen-bonds between the layers. Brucite was first described in 1824 by François Sulpice Beudant and named for the discoverer, American mineralogist, Archibald Bruce (1777–1818). A fibrous variety of brucite is called nemalite . It occurs in fibers or laths, usually elongated along [1010], but sometimes [1120] crystalline directions . A notable location in

603-453: A link, but other studies have not. The studies discuss pulmonary issues, lung cancer , and ovarian cancer . One of these, published in 1993, was a US National Toxicology Program report, which found that cosmetic grade talc containing no asbestos -like fibres was correlated with tumor formation in rats forced to inhale talc for 6 hours a day, five days a week over at least 113 weeks. A 1971 paper found particles of talc embedded in 75% of

670-504: A matting agent in earthenware glazes and can be used to produce magnesia mattes at high temperatures. ISO standard for quality (ISO 3262) Patents are pending on the use of magnesium silicate as a cement substitute. Its production requirements are less energy-intensive than ordinary Portland cement (at a heating requirement of around 650 °C for talc compared to 1500 °C for limestone to produce Portland cement), while it absorbs far more carbon dioxide as it hardens. This results in

737-421: A negative carbon footprint overall, as the cement substitute removes 0.6 tonnes of CO 2 per tonne used. This contrasts with a positive carbon footprint of 0.4 tonnes per tonne of conventional cement. Talc is used in the production of the materials that are widely used in the building interiors such as base content paints in wall coatings. Other areas that use talc to a great extent are organic agriculture ,

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804-400: A net negative charge and may be bonded together either by individual cations (such as potassium in illite or sodium or calcium in smectites) or by positively charged octahedral sheets (as in chlorites ). Clay minerals include the following groups: Mixed layer clay variations exist for most of the above groups. Ordering is described as a random or regular order and is further described by

871-405: A perfect basal cleavage and an uneven flat fracture, and it is foliated with a two-dimensional platy form. The Mohs scale of mineral hardness, based on scratch hardness comparison , defines value 1 as the hardness of talc, the softest mineral. When scraped on a streak plate , talc produces a white streak, though this indicator is of little importance, because most silicate minerals produce

938-411: A polydeformed, layered ultramafic intrusion. The France-based Luzenac Group is the world's largest supplier of mined talc. Its largest talc mine at Trimouns near Luzenac in southern France produces 400,000 tonnes of talc per year. Extraction in disputed areas of Nangarhar province , Afghanistan, has led the international monitoring group Global Witness to declare talc a conflict resource , as

1005-418: A risk of respiratory problems, including breathing trouble and serious lung damage if inhaled. The small size of the particles makes it difficult to keep them out of the air while applying the powder. Zinc oxide -based ointments are a much safer alternative. Soapstone (massive talc) is often used as a marker for welding or metalworking . Talc is also used as food additive or in pharmaceutical products as

1072-429: A significant component. For example, argillaceous limestones are limestones consisting predominantly of calcium carbonate , but including 10-40% of clay minerals: such limestones, when soft, are often called marls . Similarly, argillaceous sandstones such as greywacke , are sandstones consisting primarily of quartz grains, with the interstitial spaces filled with clay minerals. Brucite It adopts

1139-422: A significant source of magnesium for industry. Although generally deemed safe, brucite can be contaminated with naturally occurring asbestos fibers. When cement or concrete are exposed to Mg , the neoformation of brucite, an expansive material, may induce mechanical stress in the hardened cement paste or may clog the porous network creating a buffering effect and delaying the alteration/transformation of

1206-551: A subsidiary responsible for the claims in an effort to resolve the lawsuits in bankruptcy court. In 2023 J&J proposed a nearly $ 9bn settlement with 50,000 claimants saying the claims were "specious" but it wanted to move on from the issue, but judges blocked the plans, ruling that the subsidiary was not in financial distress and could not use the bankruptcy system to resolve the lawsuits. In July 2023 J&J sued researchers who linked talc to cancer alleging they used junk science to disparage company's products, while defendants say

1273-420: A traditional technique establishing fundamental occurrences or petrologic relationships. Clay minerals are common weathering products (including weathering of feldspar ) and low-temperature hydrothermal alteration products. Clay minerals are very common in soils, in fine-grained sedimentary rocks such as shale , mudstone , and siltstone and in fine-grained metamorphic slate and phyllite . Given

1340-473: A white streak. Talc is translucent to opaque, with colors ranging from whitish grey to green with a vitreous and pearly luster . Talc is not soluble in water, and is slightly soluble in dilute mineral acids . Soapstone is a metamorphic rock composed predominantly of talc. The word talc derives from Persian : تالک tālk . In ancient times, the word was used for various related minerals, including talc, mica , and selenite . Talc dominantly forms from

1407-417: Is Mg 3 (OH) 2 The combined TOT layer thus is electrically neutral. Because the hexagons in the T and O sheets are slightly different in size, the sheets are slightly distorted when they bond into a TOT layer. This breaks the hexagonal symmetry and reduces it to monoclinic or triclinic symmetry. However, the original hexahedral symmetry is discernible in the pseudotrigonal character of talc crystals. Talc

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1474-591: Is a common metamorphic mineral in metamorphic belts that contain ultramafic rocks , such as soapstone (a high-talc rock), and within whiteschist and blueschist metamorphic terranes . Prime examples of whiteschists include the Franciscan Metamorphic Belt of the western United States, the western European Alps especially in Italy, certain areas of the Musgrave Block , and some collisional orogens such as

1541-417: Is a very fine-grained geologic material that develops plasticity when wet, but becomes hard, brittle and non–plastic upon drying or firing . It is a very common material, and is the oldest known ceramic . Prehistoric humans discovered the useful properties of clay and used it for making pottery . The chemistry of clay, including its capacity to retain nutrient cations such as potassium and ammonium ,

1608-724: Is based on flat hexagonal sheets similar to those of the mica group of minerals. Standardization in terminology arose during this period as well, with special attention given to similar words that resulted in confusion, such as sheet and plane. Because clay minerals are usually (but not necessarily) ultrafine-grained, special analytical techniques are required for their identification and study. In addition to X-ray crystallography, these include electron diffraction methods, various spectroscopic methods such as Mössbauer spectroscopy , infrared spectroscopy , Raman spectroscopy , and SEM - EDS or automated mineralogy processes. These methods can be augmented by polarized light microscopy ,

1675-399: Is considered immediately dangerous to life and health . The United States Food and Drug Administration considers talc (magnesium silicate) generally recognized as safe (GRAS) to use as an anticaking agent in table salt in concentrations smaller than 2%. One particular issue with commercial use of talc is its frequent co-location in underground deposits with asbestos ore. Asbestos is

1742-504: Is formed from a stack of layers interspaced with the interlayers. Clay minerals can be classified as 1:1 or 2:1. A 1:1 clay would consist of one tetrahedral sheet and one octahedral sheet, and examples would be kaolinite and serpentinite . A 2:1 clay consists of an octahedral sheet sandwiched between two tetrahedral sheets, and examples are talc , vermiculite , and montmorillonite . The layers in 1:1 clays are uncharged and are bonded by hydrogen bonds between layers, but 2:1 layers have

1809-545: Is important to soil fertility. Because the individual particles in clay are less than 4 micrometers (0.00016 in) in size, they cannot be characterized by ordinary optical or physical methods. The crystallographic structure of clay minerals became better understood in the 1930s with advancements in the x-ray diffraction (XRD) technique indispensable to deciphering their crystal lattice. Clay particles were found to be predominantly sheet silicate (phyllosilicate) minerals, now grouped together as clay minerals. Their structure

1876-400: Is known as corrensite , R1 illite-smectite is rectorite . X-ray rf(001) is the spacing between layers in nanometers, as determined by X-ray crystallography. Glycol (mg/g) is the adsorption capacity for glycol, which occupies the interlayer sites when the clay is exposed to a vapor of ethylene glycol at 60 °C (140 °F) for eight hours. CEC is the cation exchange capacity of

1943-627: Is often used for surfaces of laboratory table tops and electrical switchboards because of its resistance to heat, electricity, and acids. In finely ground form, talc finds use as a cosmetic ( talcum powder ), as a lubricant , and as a filler in paper manufacture. It is used to coat the insides of inner tubes and rubber gloves during manufacture to keep the surfaces from sticking. Talcum powder, with heavy refinement, has been used in baby powder, an astringent powder used to prevent diaper rash (nappy rash). The American Academy of Pediatrics recommends that parents avoid using baby powder because it poses

2010-431: Is only one tetrahedral and one octahedral group in each layer the clay is known as a 1:1 clay. The alternative, known as a 2:1 clay, has two tetrahedral sheets with the unshared vertex of each sheet pointing towards each other and forming each side of the octahedral sheet. Bonding between the tetrahedral and octahedral sheets requires that the tetrahedral sheet becomes corrugated or twisted, causing ditrigonal distortion to

2077-403: Is similar to pyrophyllite , but with magnesium in the octahedral sites of the composite layers. The crystal structure of talc is described as TOT , meaning that it is composed of parallel TOT layers weakly bonded to each other by weak van der Waals forces . The TOT layers in turn consist of two tetrahedral sheets ( T ) strongly bonded to the two faces of a single trioctahedral sheet ( O ). It

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2144-400: Is the weak bonding between TOT layers that gives talc its perfect basal cleavage and softness. The tetrahedral sheets consist of silica tetrahedra, which are silicon ions surrounded by four oxygen ions. The tetrahedra each share three of their four oxygen ions with neighboring tetrahedra to produce a hexagonal sheet. The remaining oxygen ion (the apical oxygen ion) is available to bond with

2211-538: Is typical of skarnification of dolomites by silica-flooding in contact metamorphic aureoles: Talc can also be formed from magnesium chlorite and quartz in blueschist and eclogite metamorphism by the following metamorphic reaction : Talc is also found as a diagenetic mineral in sedimentary rocks where it can form from the transformation of metastable hydrated magnesium-clay precursors such as kerolite , sepiolite , or stevensite that can precipitate from marine and lake water in certain conditions. In this reaction,

2278-403: Is widely used in the ceramics industry in both bodies and glazes. In low-fire art-ware bodies, it imparts whiteness and increases thermal expansion to resist crazing . In stonewares , small percentages of talc are used to flux the body and therefore improve strength and vitrification . It is a source of MgO flux in high-temperature glazes (to control melting temperature). It is also employed as

2345-759: The Himalayas , which stretch along Pakistan , India , Nepal , and Bhutan . Talc carbonate ultramafics are typical of many areas of the Archaean cratons , notably the komatiite belts of the Yilgarn Craton in Western Australia . Talc-carbonate ultramafics are also known from the Lachlan Fold Belt , eastern Australia , from Brazil , the Guiana Shield , and from the ophiolite belts of Turkey , Oman , and

2412-530: The Middle East . China is the key world talc and steatite-producing country with an output of about 2.2M tonnes(2016), which accounts for 30% of total global output. The other major producers are Brazil (12%), India (11%), the U.S. (9%), France (6%), Finland (4%), Italy, Russia, Canada, and Austria (2%, each). Notable economic talc occurrences include the Mount Seabrook talc mine, Western Australia, formed upon

2479-407: The polymerization of RNA in aqueous solution from nucleotide monomers, and the formation of membranes from lipids. In 1998, Hyman Hartman proposed that "the first organisms were self-replicating iron-rich clays which fixed carbon dioxide into oxalic acid and other dicarboxylic acids . This system of replicating clays and their metabolic phenotype then evolved into the sulfide rich region of

2546-614: The US is Wood's Chrome Mine, Cedar Hill Quarry, Lancaster County, Pennsylvania . Yellow, white and blue brucite with a botryoidal habit was discovered in Qila Saifullah District of Province Baluchistan, Pakistan. In a later discovery, brucite also occurred in the Bela Ophiolite of Wadh, Khuzdar District , Province Baluchistan, Pakistan. Brucite has also occurred from South Africa, Italy, Russia, Canada, and other localities as well, but

2613-490: The air and inhaled. Stringent quality control since 1976, including separating cosmetic- and food-grade talc from that destined for industrial use, has largely eliminated this issue, but it remains a potential hazard requiring mitigation in the mining and processing of talc. A 2010 US FDA survey failed to find asbestos in a variety of talc-containing products. A 2018 Reuters investigation asserted that pharmaceuticals company Johnson & Johnson knew for decades that there

2680-440: The applications of clays include drug delivery, tissue engineering, and bioprinting. Clay minerals can be incorporated in lime-metakaolin mortars to improve mechanical properties. Electrochemical separation helps to obtain modified saponite-containing products with high smectite-group minerals concentrations, lower mineral particles size, more compact structure, and greater surface area. These characteristics open possibilities for

2747-571: The average pH level of 7.1 is reached at 30% of the pulp added and an experimental site with perennial grasses proved the efficacy of the technique. Moreover, the reclamation of disturbed lands is an integral part of the social and environmental responsibility of the mining company and this scenario addresses the community necessities at both local and regional levels. The results of glycol adsorption, cation exchange capacity, X-ray diffraction, differential thermal analysis, and chemical tests all give data that may be used for quantitative estimations. After

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2814-482: The clay. K 2 O (%) is the percent content of potassium oxide in the clay. DTA describes the differential thermal analysis curve of the clay. The clay hypothesis for the origin of life was proposed by Graham Cairns-Smith in 1985. It postulates that complex organic molecules arose gradually on pre-existing, non-organic replication surfaces of silicate crystals in contact with an aqueous solution. The clay mineral montmorillonite has been shown to catalyze

2881-724: The concentrations currently used in cosmetics, is safe. In July 2024, the International Agency for Research on Cancer listed talc as probably carcinogenic for humans. The study is based on limited evidence it could cause ovarian cancer in humans. In the United States, the Occupational Safety and Health Administration and National Institute for Occupational Safety and Health have set occupational exposure limits to respirable talc dusts at 2 mg/m over an eight-hour workday. At levels of 1000 mg/m, inhalation of talc

2948-449: The duration, frequency, and accumulation of hygienic talc use, few found a positive association among these factors and some found a negative one: “It may be argued that the overall null findings associated with talc-dusted diaphragms and condom use is more convincing evidence for a lack of a carcinogenic effect, especially given the lack of an established correlation between perineal dusting frequency and ovarian tissue talc concentrations and

3015-433: The dwarf planet Ceres , asteroid 101955 Bennu , and comet Tempel 1 , as well as Jupiter's moon Europa . Like all phyllosilicates, clay minerals are characterised by two-dimensional sheets of corner-sharing SiO 4 tetrahedra or AlO 4 octahedra. The sheet units have the chemical composition (Al, Si) 3 O 4 . Each silica tetrahedron shares three of its vertex oxygen ions with other tetrahedra, forming

3082-407: The food industry, cosmetics, and hygiene products such as baby powder and detergent powder . Talc is sometimes used as an adulterant to illegal heroin , to expand volume and weight and thereby increase its street value. With intravenous use, it may lead to pulmonary talcosis , a granulomatous inflammation in the lungs . Sterile talc powder ( NDC 63256-200-05) is a sclerosing agent used in

3149-454: The hexagonal array, and the octahedral sheet is flattened. This minimizes the overall bond-valence distortions of the crystallite. Depending on the composition of the tetrahedral and octahedral sheets, the layer will have no charge or will have a net negative charge. If the layers are charged this charge is balanced by interlayer cations such as Na or K or by a lone octahedral sheet. The interlayer may also contain water. The crystal structure

3216-425: The hot spring acquiring the ability to fix nitrogen . Finally phosphate was incorporated into the evolving system which allowed the synthesis of nucleotides and phospholipids." The structural and compositional versatility of clay minerals gives them interesting biological properties. Due to disc-shaped and charged surfaces, clay interacts with a range of drugs, protein, polymers, DNA, or other macromolecules. Some of

3283-547: The lack of a consistent dose-response relationship with ovarian cancer risk." Instead, the authors credited powdered talc with "a high degree of safety.” Similarly, in a 2014 article published in a leading cancer journal, the Journal of the National Cancer Institute , researchers reported the results of a survey of 61,576 postmenopausal women, more than half of whom had used talc powder perineally. The researchers compared

3350-612: The lawsuits are meant to silence scientists. Clay mineral Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin , Al 2 Si 2 O 5 ( OH ) 4 ), sometimes with variable amounts of iron , magnesium , alkali metals , alkaline earths , and other cations found on or near some planetary surfaces . Clay minerals form in the presence of water and have been important to life, and many theories of abiogenesis involve them. They are important constituents of soils , and have been useful to humans since ancient times in agriculture and manufacturing . Clay

3417-452: The manufacture of high-quality ceramics and heavy-metal sorbents from saponite-containing products. Furthermore, tail grinding occurs during the preparation of the raw material for ceramics; this waste reprocessing is of high importance for the use of clay pulp as a neutralizing agent, as fine particles are required for the reaction. Experiments on the histosol deacidification with the alkaline clay slurry demonstrated that neutralization with

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3484-407: The metamorphism of magnesian minerals such as serpentine , pyroxene , amphibole , and olivine , in the presence of carbon dioxide and water. This is known as "talc carbonation" or "steatization" and produces a suite of rocks known as talc carbonates . Talc is primarily formed by hydration and carbonation by this reaction: Talc can also be formed via a reaction between dolomite and silica, which

3551-496: The most notable discoveries are the US, Russian and Pakistani examples. Synthetic brucite is mainly consumed as a precursor to magnesia (MgO), a useful refractory and thermal insulator . It finds some use as a flame retardant because it thermally decomposes to release water in a similar way to aluminium hydroxide ( Al(OH) 3 ) and mixtures of huntite ( Mg 3 Ca(CO 3 ) 4 ) and hydromagnesite ( Mg 5 (CO 3 ) 4 (OH) 2 ·4H 2 O ). It also constitutes

3618-462: The ovarian tumors studied. In 2018, Health Canada issued a warning against inhaling talcum powder or women's using it perineally. In contrast, however, research published in 1995 and 2000 concluded that, although it was plausible that talc could cause ovarian cancer, no conclusive evidence had been shown. Further, a 2008 European Journal of Cancer Prevention review of ovarian cancer and talc use studies pointed out that, although many of them examined

3685-534: The ovaries and lungs. According to the IARC , talc containing asbestos is classified as a group 1 agent (carcinogenic to humans), talc use in the perineum is classified as group 2B (possibly carcinogenic to humans), and talc not containing asbestos is classified as group 2A (probably carcinogenic to humans). Reviews by Cancer Research UK and the American Cancer Society conclude that some studies have found

3752-489: The procedure of pleurodesis . This can be helpful as a cancer treatment to prevent pleural effusions (an abnormal collection of fluid in the space between the lungs and the thoracic wall ). It is inserted into the space via a chest tube, causing it to close up, so fluid cannot collect there. The product can be sterilized by dry heat, ethylene oxide , or gamma irradiation . Suspicions have been raised that talc use contributes to certain types of disease, mainly cancers of

3819-458: The profits are used to fund armed confrontation between the Taliban and Islamic State . Talc is used in many industries, including paper making, plastic , paint and coatings (e.g. for metal casting molds), rubber, food, electric cable, pharmaceuticals, cosmetics, and ceramics. A coarse grayish-green high-talc rock is soapstone or steatite , used for stoves, sinks, electrical switchboards, etc. It

3886-452: The quantities of organic matter, carbonates, free oxides, and nonclay minerals have been determined, the percentages of clay minerals are estimated using the appropriate glycol adsorption, cation exchange capacity, K20, and DTA data. The amount of illite is estimated from the K20 content since this is the only clay mineral containing potassium. Argillaceous rocks are those in which clay minerals are

3953-422: The ratio of talc and kyanite depends on aluminium content, with more aluminous rocks favoring production of kyanite. This is typically associated with high-pressure, low-temperature minerals such as phengite , garnet , and glaucophane within the lower blueschist facies . Such rocks are typically white, friable, and fibrous, and are known as whiteschist . Talc is a trioctahedral layered mineral; its structure

4020-581: The requirement of water, clay minerals are relatively rare in the Solar System , though they occur extensively on Earth where water has interacted with other minerals and organic matter . Clay minerals have been detected at several locations on Mars , including Echus Chasma , Mawrth Vallis , the Memnonia quadrangle and the Elysium quadrangle . Spectrography has confirmed their presence on celestial bodies including

4087-565: The subjects’ reports of their own talc use with their reports of having had ovarian cancer diagnosed by their doctors, and found, regardless of subjects’ age and tubal ligation status, “Ever use of perineal powder ... was not associated with risk of ovarian cancer compared with never use,” nor was any greater individual cancer risk associated with longer use of talc powder. On this basis, the article concluded, “perineal powder use does not appear to influence ovarian cancer risk.” The Cosmetic Ingredient Review Expert Panel concluded in 2015 that talc, in

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4154-414: The talc-based powder is safe to use and does not contain asbestos. In 2006 the International Agency for Research on Cancer classified talcum powder as a possible human carcinogen if used in the female genital area. Despite this, no federal agency in the US acted to remove talcum powder from the market or add warnings. In February 2016, as the result of a lawsuit against Johnson & Johnson (J&J),

4221-437: The term reichweite , which is German for range or reach. Literature articles will refer to an R1 ordered illite-smectite, for example. This type would be ordered in an illite-smectite-illite-smectite (ISIS) fashion. R0 on the other hand describes random ordering, and other advanced ordering types are also found (R3, etc.). Mixed layer clay minerals which are perfect R1 types often get their own names. R1 ordered chlorite-smectite

4288-402: The tetrahedral sheet also forms part of one side of the octahedral sheet, but an additional oxygen atom is located above the gap in the tetrahedral sheet at the center of the six tetrahedra. This oxygen atom is bonded to a hydrogen atom forming an OH group in the clay structure. Clays can be categorized depending on the way that tetrahedral and octahedral sheets are packaged into layers . If there

4355-447: The trioctahedral sheet. The trioctahedral sheet has the structure of a sheet of the mineral brucite . Apical oxygens take the place of some of the hydroxyl ions that would be present in a brucite sheet, bonding the tetrahedral sheets tightly to the trioctahedral sheet. Tetrahedral sheets have a negative charge, since their bulk composition is Si 4 O 10 . The trioctahedral sheet has an equal positive charge, since its bulk composition

4422-433: The verdict. The judge stated that Echeverria proved there is "an ongoing debate in the scientific and medical community about whether talc more probably than not causes ovarian cancer and thus (gives) rise to a duty to warn", but not enough to sustain the jury's imposition of liability against Johnson & Johnson stated, and concluded that Echeverria did not adequately establish that talc causes ovarian cancer. In July 2018,

4489-514: Was asbestos in its baby powder, and in 2020 the company stopped selling its baby powder in the US and Canada. There were calls for Johnson & Johnson's largest shareholders to force the company to end global sales of baby powder, and hire an independent firm to conduct a racial justice audit as it had been marketed to African American and overweight women. On August 11, 2022, the company announced it would stop making talc-based powder by 2023 and replace it with cornstarch-based powders. The company said

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