Initiated in 1994, the Siloxane Research Program (SRP) represents the largest voluntary health and safety program ever conducted on siloxanes, a commonly used type of silicone material.
SRP has an external Science Advisory Board, which includes nationally and internationally renowned scientists. The Advisory Board provides an independent review of SRP strategy, methodology and findings. Independent universities and qualified laboratories also perform and review many of the tests and studies. Hundreds of studies have been completed to date on six types of siloxanes. Our findings continue to support the safe use of our materials in their intended applications.
Full copies of the reports listed below can be obtained by contacting the U.S. Environmental Protection Agency (EPA) at oppt.ncic@epa.gov or on (202) 566-0280 and providing the EPA Document Control Number (EPA DCN). Click on the report title to see a copy of the study's key findings and summary.
| Octamethylcyclotetrasiloxane (D4) | |||
| Report Title | EPA DCN | Completion Date | |
| Disposition of Octamethylcyclotetrasiloxane (D4) in Female Fischer 344 and Sprague-Dawley IGS Rats Following 14 Repeat Nose-Only Vapor Inhalation Exposures and a Single Exposure to 14C-D4 at 700 ppm | 84030000028 | 12/2/02 | |
| Effects of Octamethylcyclotetrasiloxane (D4) on Cell Proliferation in the Rat | 84030000006 | 11/21/02 | |
| Determination of the Effects of Octamethylcyclotetrasiloxane (D4) on the LH Surge and Levels of Various Sex Hormones in Female Sprague-Dawley Rats | 84030000005 | 10/30/02 | |
| Effects of Octamethylcyclotetrasiloxane (D4) on Liver Size and Hepatic Phase I and Phase II Xenobiotic Metabolizing Enzymes in Rats and Guinea Pigs Following 14-Day Oral Gavage: A Study of Species-Specific Response | 84030000007 | 7/11/02 | |
| Single Exposure Pharmacokinetics and Metabolism of 4C-Decamethylcyclopentasiloxane (D5) via Nose-Only Vapor Inhalation | 84030000027 | 2/8/02 | |
| A Two-Generation Inhalation Reproductive Toxicity and Developmental Neurotoxicity Study of Octamethylcyclotetrasiloxane (D4) in Rats | 88020000003 | 12/21/01 | |
| In-Vitro Human Cytochrome P450 Metabolism of D4 | 84020000003 | 11/15/01 | |
| Dose-Response Modeling of Cytrochrome P450 Induction I Rats by Octamethylcyclotetrasiloxane (D4) | 84020000006 | 9/20/01 | |
| In-vitro Evaluation of Estrogenicity of Octamethylcyclotetrasiloxane (D4) Using the Human MCF-7 Cell Line | 86010000004 | 8/15/01 | |
| Determination of both Parent Octamethylcyclotetrasiloxane (D4) and 14C-D4 in Female Sprague Dawley and Fischer 344 Rats Following a Single Nose-Only Vapor Inhalation Exposure to 700 ppm D4 | 86010000010 | 12/12/2000 | |
| Absorption, Distribution and Elimination of 13C D4 in Humans after Dermal Administration | 86010000007 | 9/19/2000 | |
| In Vivo Dermal ADME of C14-D4 in Fischer 344 Rats (to clarify expired air values) | 86010000009 | 9/1/2000 | |
| Percutaneous Absorption Studies of Neat and Formulated Octamethylcyclotetrasiloxane (D4) in Human Skin/Nude Mouse Model | 86010000003 | 8/14/2000 | |
| PBPK1 Modelling of D4 Inhalation PK Studies in Rats and Humans | 86010000005 | 6/21/2000 | |
| Interim Exposure Assessment for Silicone Antifoams in Food Processing and Over-the-Counter (OTC) Antigas (AG) Products | 84010000004 | 11/29/1999 | |
| An Inhalation Reproductive Toxicity Study of Octamethylcyclotetrasiloxane (D4) in Female Rats Using Multiple and Single-Day Exposure Regimens | 86990000058 | 6/14/1999 | |
| D4 Rat Uterotrophic Assay | 84000000002 | 5/26/1999 | |
| Interim Risk Assessment of D4 Reproductive Effects | 86990000059 | 4/26/1999 | |
| Effects of Repeated Whole Body Inhalation Exposure to Octamethylcyclotetrasiloxane (D4) Vapors on Hepatic Microsomal CYP2B1/2 Induction in Female Fischer 344 Rats: A Dose-Response Study | 86990000029 | 2/28/1999 | |
| Clinical Studies on the Immune Effects of Gastrointestinal Exposure to Octamethylcyclotetrasiloxane (D4) | 86990000015 | 11/10/1998 | |
| Exposure Assessment for D4, D5 and D6 | 86990000021 | 10/14/1998 | |
| An Oral Gavage Study to Compare the Absorption Potential of 14C-Octamethylcyclotetrasiloxane (D4) in Fischer 344 Rats When Delivered in Various Carriers | 86980000184 | 9/1/1998 | |
| Absorption of C14-Octamethylcyclotetrasiloxane Using the Flow-Through Diffusion Cell System for In-vitro Dermal Absorption in Human Skin | 86980000163 | 6/26/1998 | |
| Evaluation of Octamethylcyclotetrasiloxane (D4) as an Inhibitor of Human Cytochrome P450 Enzymes | 86990000017 | 6/1/1998 | |
| An Inhalation Reproductive Toxicity Study of Octamethylcyclotetrasiloxane (D4) in Female Rats Using Multiple Exposure Regimems | 86980000153 | 5/22/1998 | |
| Immunological Evaluation of D4 Using 28-Day Exposure in Male and Female Rats | 86980000072 | 12/1/1997 | |
| An Inhalation Range-Finding Reproductive Toxicity Study of Octamethylcyclotetrasiloxane (D4) in Male Rats | 86980000061 | 11/1/1997 | |
| An Inhalation Range-Finding Reproductive Toxicity Study of Octamethylcyclotetrasiloxane (D4) in Male Rats | 86980000049 | 11/1/1997 | |
| A Pilot Study to Determine if Classical Inducing Agents Alter the Metabolic Profile of a Single Dose of 14C-Octamethylcyclotetrasiloxane (D4) in Rats | 86980000037 | 10/3/1997 | |
| A Subchronic Toxicological Evaluation and Splenic Antibody Forming Cell Response in Sheep Erthrocytes Following a 28-day whole body inhalation Exposure with D4 in the Rat | 86980000040 | 9/30/1997 | |
| Clinical Studies on the Respiratory Effects of Octamethylcyclotetrasiloxane (D4): Mouthpiece and Nasal Exposures | 86980000017 | 9/1/1997 | |
| Non-Regulated Study: Identification of Major Metabolites of Octamethylcyclotetrasiloxane (D4) in Rat Urine | 86980000032 | 8/26/1997 | |
| Pharmacokinetics of 14C-Octamethylcyclotetrasiloxane in the Rat Following 14 Repeat Daily Nose-Only Vapor Inhalation Exposures to Unlabelled D4 and a Single (Day 15) Exposure to 14C-D4 at Two Dose Levels | 86970000875 | 8/25/1997 | |
| Female Rat Inhalation Reproductive Study of Octamethylcyclotetrasiloxane (D4) | 86970000847 | 8/1/1997 | |
| Effects of D4 on Liver Enlargement and Enzyme Induction: A Pilot Feasibility Study II | 86970000725 | 2/25/1997 | |
| Pharmacokinetics of 14C-Octamethylcyclotetrasiloxane (D4) in the Rat Following Single Nose-Only Vapor Inhalation Exposure | 86970000024 | 10/14/1996 | |
| Effects of Octamethylcyclotetrasiloxane on liver size and enzyme induction: A Pilot Feasibility Study | 86970000723 | 10/2/1996 | |
| An Inhalation Range-Finding Reproductive Toxicity Study of Octamethylcyclotetrasiloxane (D4) in Rats | 86970000023 | 9/11/1996 | |
| Method Development for the Determination of 14C-Octamethylcyclotetrasiloxane (D4) Pharmacokinetics in the Male Rat Following Single Nose-Only Vapor Inhalation Exposure | 86960000564 | 8/15/1996 | |
| A Pilot Study for the Determination of 14C-Octamethylcyclotetrasiloxane (D4) Pharmacokinetics in Fischer 344 Rats Following a single Nose-Only Vapor Inhalation Exposure to 700 PPM 14C-D4 | 86960000517 | 7/3/1996 | |
| An Inhalation Range-Finding Reproductive Toxicity Study of Octamethylcyclotetrasiloxane (D4) in Rats | 86960000398 | 5/7/1996 | |
| One-Month Repeated Dose Inhalation Toxicity Study with Octamethylcyclotetrasiloxane in Rats | 86950000155 | 3/14/1995 | |
| Three-Month Repeated Dose Inhalation Toxicity Study with Octamethylcyclotetrasiloxane in Rats | 86950000153 | 3/14/1995 | |
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| Decamethylcyclopentasiloxane (D5) | |||
| Report Title | EPA DCN | Completion Date | |
| Single Exposure Pharmacokinetics and Metabolism of 4C-Decamethylcyclopentasiloxane (D5) via Nose-Only Vapor Inhalation | 84030000027 | 2/8/02 | |
| Absorption, Distribution and Elimination of D143-D5 in Humans after Dermal Administration | 84030000008 | 1/21/02 | |
| D5 Inhalation Pharmacokinetic Pilot Study with Respiratory Measurements | 86010000001 | 1/12/2001 | |
| Evaluation of Decamethylcyclopentasiloxane (D5) as an Inhibitor of Human and Rat Cytochrome P450 Enzymes | 86010000008 | 2/4/2000 | |
| In-vitro human dermal adsorption of decamethylcyclopentasiloxane | 86000000017 | 11/5/1999 | |
| A Two-Generation Inhalation reproductive Toxicity and Developmental Neurotoxicity Study of Decamethylcyclopentasiloxane (D5) in Rats | 86990000032 | 3/31/1999 | |
| Exposure Assessment for D4, D5 and D6 | 86990000021 | 10/14/1998 | |
| Effects of Decamethylcyclopentasiloxane on Hepatic Cytochrom P450 in the Female Fischer 344 Rat | 86980000020 | 9/22/1997 | |
| A 28-Day Inhalation Toxicity and Splenic Antibody Formation Study of Decamethylcyclopentasiloxane (D5) in Rats | 86970000385 | 12/4/1996 | |
| In Vivo Percutaneous Absorption of 14C-Decamethylcyclopentasiloxane (D5) in Rat Skin | 86970000009 | 9/30/1996 | |
| An Inhalation Range-Finding Reproductive Toxicity Study of Decamethylcyclopentasiloxane (D5) in the Rat | 86970000006 | 9/12/1996 | |
| In Vitro Percutaneous Absorption of 14C-D5 in Rat Skin | 86960000593 | 8/14/1996 | |
| Three-Month Repeated Dose Inhalation Toxicity Study with Decamethylcyclopentasiloxane in Rats | 86950000154 | 4/2/1995 | |
| One-Month Repeated Dose Inhalation Toxicity Study with Decamethylcyclopentasiloxane in Rats | 86950000174 | 4/2/1995 | |
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| Dodecamethylcyclohexasiloxane (D6) | |||
| Report Title | EPA DCN | Completion Date | |
| Pharmacokinetics of 14C-D6 in the Rat Following Single Oral Exposure | 84040000016 | 4/2/04 | |
| Absorption of Dodecamethylcyclohexasiloxane (D6) Using the Flow-Through Diffusion Cell System for In Vitro Absorption in Human Skin | 84030000026 | 1/15/03 | |
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| Hexamethyldisiloxane (HMDS) | |||
| Report Title | EPA DCN | Completion Date | |
| Non-Regulated Study: A One-Week Vapor Inhalation Study to Evaluate by Immunohistochemistry the Effect of Hexamethyldisiloxane (HMDS) on Alpha 2u-Globulin Accumulation in the Kidneys of Male Fischer 344 Rats | 84030000025 | 1/22/03 | |
| Non-Regulated Study: Identification of Metabolites of Hexamethyldisiloxane (HMDS) | 86020000001 | 1/31/01 | |
| A Range-Finding Reproductive Toxicity Study of HMDS in Rats | 86000000019 | 2/3/2000 | |
| Three-Month Repeated Dose Whole Body Inhalation Toxicity Study with Hexamethyldisiloxane in Rats | 86980000182 | 8/1/1998 | |
| One-Month Repeated Dose Inhalation Toxicity Study with Hexamethyldisiloxane in Rats | 86980000041 | 11/14/1997 | |
| Three-Month Repeated Dose Inhalation Toxicity Study with Hexamethyldisiloxane in Rats | 86980000048 | 10/3/1997 | |
| An Acute Whole Body Inhalation Study of Hexamethyldisiloxane in Albino Rats | 86970000724 | 1/17/1997 | |
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| Polydimethylsiloxane (PDMS) | |||
| Report Title | EPA DCN | Completion Date | |
| A Chronic Toxicity Study of 10cs Polydimethylsiloxane Fluid in Rats | 84040000015 | 12/17/03 | |
| Pharmacokinetics of 14C-PDMS 350cs by Oral Gavage in Rats | 84020000001 | 11/21/01 | |
| Pharmacokinetics of 14C-PDMS 10cs by oral gavage in Rats | 86010000006 | 12/1/2000 | |
| A 13-Week Subchronic Toxicity Study of Dow Corning® 200 Fluid, 10cst in Rats | 86860000269 | 11/7/1995 | |
| A 13-Week Subchronic Toxicity Study of Dow Corning® 200 Fluid, 350 cst in Rats | 86960000270 | 11/7/1995 | |
| A 28-Day Oral Toxicity Study of Dow Corning® 200 Fluid, 10 cst in Rats | 86960000128 | 8/30/1995 | |
| A 28-Day Oral Toxicity Study of Dow Corning® 200 Fluid, 350 cst in Rats | 86960000130 | 8/30/1995 | |
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| Siloxanes | |||
| Report Title | EPA DCN | Completion Date | |
| Non-Regulated Study: In Vitro Effects of Siloxanes on Human Immune Cells | 84020000005 | 6/25/01 | |
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