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Cyclic siloxanes are widely used in beauty products as softener and polisher. Howeve, very few studies have reported the occurrence and amount of cyclic siloxanes in personal care products (PCPs). In this research, the analysis method of cyclic siloxanes including octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in PCPs was developed by using a gas chromatography-mass spectrometry (GC/MS) system. The method detection limits and the method quantification limits of individual cyclic siloxanes were 0.7 ng/g and 2.0 ng/g, respectively. Mean recoveries of surrogate compound (M4Q) and target compounds for the procedural blanks ranged from 88.5 to 94.9%. The recoveries of M4Q for real samples ranged from 75.5 to 120% (RSD: 6.8%). The optimal procedure was applied to measure the amount of D4, D5, and D6 in several samples of PCPs including shampoos, hair gels, and shower gels collected from retail stores in Hanoi, Vietnam. Mean concentrations of D4, D5 and D6 in PCPs ranged of 0.313 – 5.61 µg/g, 0.683 – 11.7 µg/g, and 0.294 – 3.38 µg/g, respectively.
 Burn-Naas, L.A., Meeks, R.G., Kolesar, G.B., Mast, R.W., Elwell, M.R., Hardisty, J.F., Thevenaz, P., 2002. Inhalation toxicology of octamethylcyclotetrasiloxane (D4) following a 3-month nose-only exposure in Fischer 344 rats. Int. Toxicol. 21, 39-53.
 Dekant, W., Klaunig, E.J., 2016. Toxicology of decamethylcyclopentasiloxane (D5). Regul. Toxicol. Pharmacol. 74, S67-S76.
 Environment Canada, Health Canada, 2011. Screening assessment for the challenge: Siloxanes and silicones, di-Me, hydrogen-terminated: Chemical abstracts service registry number 70900-21-9. Government of Canada. Available: http://www.ec.gc.ca/ese-ees/default.asp?lang=En&n=4996570F-1#top.
 He, B., Rhoders-Brower, S., Miller, M.R., Munson, A.E., Germolec, D.R., Walker, V.R., Korach, K.S., Meade, B.J., 2003. Octamethylcyclotetrasiloxane exhibits estrogenic activity in mice via ERα. Toxicol. App. Pharm. 192, 254-261.
 Horii, Y., Kannan, K., 2008. Survey of organosiloxane compounds, including cyclic and linear siloxanes, in personal-care and household products. Arch. Environ. Contam. Toxicol. 55, 701-710.
 Lu, Y., Yuan, T., Wang, W., Kannan, K., 2011. Concentration and assessment of exposure to siloxanes and synthetic musks in personal care products from China. Environ. Pollut. 159, 3522-3528.
 Meeks, R.G., Stump, D.G., Siddiqui, W.H., Holson, J.F., Plotzke, K.P., Reynolds, V.L., 2007. An inhalation reproductive toxicity study of octamethylcyclotetrasiloxane (D4) in female rats using multiple and single day exposure regimens. Reprod. Toxicol. 23, 192-201.
 Siddiqui, W.H., Stump, D.G., Plotzke, K.P., Holson, J.F., Meeks, R.G., 2007. A two-generation reproductive toxicity study of octamethylcyclotetrasiloxane (D4) in rats exposed by whole-body vapor inhalation. Reprod. Toxicol. 23, 202-215.
 Tran, M.T., Abualnaja, O.K., Asimakopoulos, G.A., Covaci, A., Gevao, B., Johnson-Restrepo, B., Kumosani, A.T., Malarvannan, G., Minh, B.T., Moon, B.H., Nakata, H., Sinha, K.R., Kannan, K., 2015. A survey of cyclic and linear siloxanes in indoor dust and their implications for human exposures in twelve countries. Environ. Int. 78, 39-44.
 Tran, M.T., Kannan, K., 2015. Occurrence of cyclic and linear siloxanes in indoor air from Albany, New York, USA, and its implications for inhalation exposure. Sci. Total Environ. 511, 138-144.
 Tran, M.T., Le, T.H., Vu, D.N., Dang, M.H.G., Minh, B.T., Kannan, K. 2017. Cyclic and linear siloxanes in indoor air from several northern cities in Vietnam: Levels, spatial distribution and human exposure. Chemosphere 184, 1117-1124.
 Wang, R., Moody, R.P., Koniecki, D., Zhu, J., 2009. Low molecular weight cyclic volatile methylsiloxanes in cosmetic products sold on Canada: Implication for dermal exposure. Environ. Int. 35, 900-904.