Editing Talc (section)

==Safety==
Suspicions have been raised that talc use contributes to certain types of disease, mainly cancers of the ovaries and lungs. According to the [[International Agency for Research on Cancer|IARC]], talc containing asbestos is classified as a [[IARC group 1|group 1 agent]] (carcinogenic to humans), talc use in the [[perineum]] is classified as [[IARC group 2B|group 2B]] (possibly carcinogenic to humans), and talc not containing asbestos is classified as [[IARC group 2A|group 2A]] (probably carcinogenic to humans).<ref>[http://monographs.iarc.fr/ENG/Classification/latest_classif.php List of Classifications], International Agency for Research on Cancer</ref> Reviews by [[Cancer Research UK]] and the [[American Cancer Society]] conclude that some studies have found a link, but other studies have not.<ref>[http://info.cancerresearchuk.org/healthyliving/cancercontroversies/talcum-powder/ Talcum powder and cancer] {{Webarchive|url=https://web.archive.org/web/20120815024743/http://info.cancerresearchuk.org/healthyliving/cancercontroversies/talcum-powder/ |date=15 August 2012 }}, Cancerresearch.uk</ref><ref>[http://www.cancer.org/Cancer/CancerCauses/OtherCarcinogens/AtHome/talcum-powder-and-cancer Talcum Powder and Cancer] {{Webarchive|url=https://web.archive.org/web/20161120023848/http://www.cancer.org/cancer/cancercauses/othercarcinogens/athome/talcum-powder-and-cancer |date=20 November 2016 }}, American Cancer Society</ref>

The studies discuss [[Lung|pulmonary]] issues,<ref>
{{cite journal
|pmid=2198684|title=Pulmonary toxicity of inhaled and intravenous talc|year=1990
|last1=Hollinger
|first1=MA
|volume=52
|issue=2
|pages=121–7; discussion 117–9
|journal=[[Toxicology Letters]]
|doi=10.1016/0378-4274(90)90145-C}}
</ref> [[lung cancer]],<ref name="NTP">
{{cite journal
|pmid=12616290
|url=https://ntp.niehs.nih.gov/go/tr421abs
|title=NTP Toxicology and Carcinogenesis Studies of Talc (Non-Asbestiform) in Rats and Mice (Inhalation Studies)|year=1993
|last1=National Toxicology
|first1=Program
|volume=421
|pages=1–287
|journal=National Toxicology Program Technical Report Series}}</ref><ref>{{Cite web |date=1995 |title=Worker Health Study Summaries – Talc Miners & Millers |url=https://www.cdc.gov/niosh/pgms/worknotify/Talc.html |url-status=live |archive-url=https://web.archive.org/web/20220707125712/https://www.cdc.gov/niosh/pgms/worknotify/Talc.html |archive-date=2022-07-07 |access-date=2022-08-31 |website=The National Institute for Occupational Safety and Health (NIOSH)}}</ref> and [[ovarian cancer]].<ref>
{{cite journal|pmid=1603491|title=Perineal exposure to talc and ovarian cancer risk
|author=Harlow, Cramer, Bell|year=1992|volume=80|issue=1|pages=19–26|journal=Obstetrics and Gynecology|display-authors=etal}}</ref> 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 [[rat]]s forced to inhale talc for 6 hours a day, five days a week over at least 113 weeks.<ref name="NTP" /> A 1971 paper found particles of talc embedded in 75% of the ovarian tumors studied.<ref>
{{cite journal
|pmid=5558843|title=Talc and carcinoma of the ovary and cervix|vauthors=Henderson WJ, Joslin CA, Turnbull AC, Griffiths K |year=1971
|journal=J Obstet Gynaecol Br Commonw|volume=78|issue=3|pages=266–272
|doi=10.1111/j.1471-0528.1971.tb00267.x|s2cid=32300387}}
</ref> In 2018, [[Health Canada]] issued a warning against inhaling talcum powder or women's using it perineally.<ref>{{Cite web|url=https://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2018/68320a-eng.php|title=Talc – Potential Risk of Lung Effects and Ovarian Cancer|date=19 November 2018}}</ref>

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.<ref>{{cite journal|last1=Harlow|first1=BL|last2=Hartge|first2=PA|title=A review of perineal talc exposure and risk of ovarian cancer.|journal=[[Regulatory Toxicology and Pharmacology]] |date=Apr 1995|volume=21|issue=2|pages=254–60|pmid=7644715|doi=10.1006/rtph.1995.1039|url=https://zenodo.org/record/1229955}}</ref><ref>{{cite journal|last1=Gertig|first1=D. M.|last2=Hunter|first2=D. J.|last3=Cramer|first3=D. W.|last4=Colditz|first4=G. A.|last5=Speizer|first5=F. E.|author5-link=Frank E. Speizer|last6=Willett|first6=W. C.|last7=Hankinson|first7=S. E.|title=Prospective Study of Talc Use and Ovarian Cancer|journal=JNCI Journal of the National Cancer Institute|date=2 February 2000|volume=92|issue=3|pages=249–252|doi=10.1093/jnci/92.3.249|doi-broken-date=1 May 2025 |pmid=10655442|url=https://academic.oup.com/jnci/article-pdf/92/3/249/9996398/249.pdf}}</ref> Further, a 2008 [[European Journal of Cancer Prevention]] review of ovarian cancer and talc use studies pointed out that, although many of them examined 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 the lack of a consistent dose-response relationship with ovarian cancer risk." Instead, the authors credited powdered talc with "a high degree of safety.”<ref>{{cite journal|last1=Muscat|first1=Joshua E.|last2=Huncharek|first2=Michael S.|title=Perineal Talc Use and Ovarian Cancer: A Critical Review|journal=European Journal of Cancer Prevention|date=April 2008|volume=17|issue=2|pages=139–146|doi=10.1097/CEJ.0b013e32811080ef|pmid=18287871|pmc=3621109}}</ref>

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 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.”<ref>{{cite journal|last1=Houghton|first1=Serena C.|last2=Reeves|first2=Katherine W.|last3=Hankinson|first3=Susan E.|last4=Crawford|first4=Lori|last5=Lane|first5=Dorothy|last6=Wactawski-Wende|first6=Jean|last7=Thomson|first7=Cynthia A.|last8=Ockene|first8=Judith K.|title=Perineal Powder Use and Risk of Ovarian Cancer|journal=JNCI Journal of the National Cancer Institute|date=11 September 2014|volume=106|issue=9|pages=dju208 |doi=10.1093/jnci/dju208|pmid=25214560|url=https://academic.oup.com/jnci/article/106/9/dju208/910075|pmc=4200058}}</ref> The [[Cosmetic Ingredient Review|Cosmetic Ingredient Review Expert Panel]] concluded in 2015 that talc, in the concentrations currently used in cosmetics, is safe.<ref>{{cite journal |last1=Gruber |first1=James |title=Do Cosmetic Consumers Really Know What Ingredients They Are Using? An Inquiry into the Search for the 'Truth' |journal=Skeptical Inquirer |date=November–December 2019 |volume=43 |issue=6 |page=54}}</ref>

In July 2024, the [[International Agency for Research on Cancer]] listed talc as "probably" [[Carcinogen|carcinogenic]] for humans. The study is based on limited evidence it could cause [[ovarian cancer]] in humans.<ref>{{cite news |last1= |first1= |title=WHO agency says talc is 'probably' cancer-causing|url=https://globalnation.inquirer.net/241682/who-agency-says-talc-is-probably-cancer-causing |accessdate=July 7, 2024 |publisher= [[Philippine Daily Inquirer]]|date=July 6, 2024}}</ref>{{better source|reason= Unlike other layperson medical reporting sites (e.g., Medical Xpress), this article does not provide a link to the WHO publication for verification. A second source doing so would be very useful.|date=January 2025}}

===Industrial grade===
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&nbsp;mg/m<sup>3</sup> over an eight-hour workday. At levels of 1000&nbsp;mg/m<sup>3</sup>, inhalation of talc is considered [[immediately dangerous to life and health]].<ref>
{{cite web|title = NIOSH Pocket Guide to Chemical Hazards|publisher = Centers for Disease Control and Prevention|year=2011|url = https://www.cdc.gov/niosh/npg/npgd0584.html}}</ref>

===Food grade===
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%.<ref>
{{cite web
|title = Code of Federal Regulations
|publisher = U.S. Food and Drug Administration|year=2009
|url = http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=182.2437}}
</ref>

===Association with asbestos===
One particular issue with commercial use of talc is its frequent co-location in underground deposits with [[asbestos]] ore. Asbestos is a general term for different types of fibrous silicate minerals, desirable in construction for their heat resistant properties.<ref>{{cite web |title=Asbestos |url=https://mineralseducationcoalition.org/minerals-database/asbestos/ |website=Minerals Education Coalition}}</ref> There are six varieties of asbestos; the most common variety in manufacturing, [[white asbestos]], is in the [[serpentine subgroup|serpentine]] family.<ref>{{cite book |last1=Plummer |first1=Charles C. |last2=Carlson |first2=Diane H. |last3=Hammersley |first3=Lisa |title=Physical Geology |isbn=9781260091656 |edition=Sixteenth|date=22 January 2018 |publisher=McGraw-Hill Education }}</ref> Serpentine minerals are [[sheet silicate]]s; 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 the air and inhaled. Stringent quality control since 1976, including separating [[cosmetic-grade|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.<ref>{{cite news |title=Is talcum powder asbestos? |url=https://www.straightdope.com/columns/read/996/is-talcum-powder-asbestos/ |website=[[The Straight Dope]] |date=16 February 1990 |access-date=9 March 2019}}</ref> A 2010 US [[FDA]] survey failed to find asbestos in a variety of talc-containing products.<ref>
{{cite web
|title = Talc Ingredients
|publisher = U.S. Food and Drug Administration|year=2010
|url = https://www.fda.gov/Cosmetics/ProductsIngredients/Ingredients/ucm293184.htm}}</ref> A 2018 [[Reuters]] investigation asserted that pharmaceuticals company [[Johnson & Johnson]] knew for decades that there was asbestos in its baby powder,<ref>{{Cite news|url=https://www.reuters.com/investigates/special-report/johnsonandjohnson-cancer/|title=J&J knew for decades that asbestos lurked in its Baby Powder|work=Reuters|language=en|access-date=2018-12-15}}</ref> and in 2020 the company stopped selling its baby powder in the US and Canada.<ref>{{cite news |title=Johnson & Johnson stops selling baby powder in US |url=https://www.bbc.co.uk/news/business-52732755 |access-date=20 May 2020 |work=BBC News |date=20 May 2020}}</ref> 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.<ref>{{Cite news |title=Johnson & Johnson shareholders called on to end talc baby powder sales |last=Perkins |first=Tom |newspaper=The Guardian |date=27 April 2022 |url= https://www.theguardian.com/business/2022/apr/27/johnson-and-johnson-baby-powder-talc-shareholders}}</ref> 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 the talc-based powder is safe to use and does not contain asbestos.<ref>{{cite news|url=https://www.bbc.com/news/business-62514263 | title=J&J to replace talc-based powder with cornstarch after cancer lawsuits | date=August 12, 2022 | publisher=BBC News  |access-date=August 12, 2022 }}</ref>