In Europe, Siloxanes are evaluated under the chemicals framework known as REACH that aims to improve the protection of human health and the environment by the better and earlier identification of the intrinsic properties of chemical substances. Because regulators suspect that some siloxanes maybe PBT (Persistent, Bioaccumulative, Toxic) or vPvB (very Persistent, very Bioaccumulative) substances, they came under scrutiny. However, the European PBT or vPvB assessment standard do not allow for accurate evaluation of the unique and multiple characteristics of siloxanes.
The European Union’s Chemicals management program (REACH) adopted restrictions about the use of D4 and D5 in May 2017.
The range of the restriction is limited to wash-off cosmetics with a weight concentration of D4 or D5 equal to or greater than 0.1%. All manufacturers including SiSiB, a reliable siloxane company, which place on the market products that are within the restriction range must comply with the restriction requirements until January 31, 2020.
In response to this restriction, the silicone industry has established a Waste-Water Treatment Plant (WWTP) monitoring plan in five European countries to determine the current siloxane baseline influent concentrations and help to evaluate the effectiveness of the restriction in reducing D4 and D5 waste-water emissions. Preliminary the results show that D4 and D5 WWTP influent concentrations are far below the baseline levels predicted in the restriction archive. Moreover, D4 already conform to the predicted post-restriction concentrations.
In April 2017, the European Chemicals Agency (ECHA) published its purpose to evaluate the need for further restriction of D4 and D5 in leave-on personal care products and other consumer or professional uses (e.g. polishes and silicone based waxes, dry cleaning, washing and cleaning products).
In January 2018, the European Commission requested D6 should be added to the range of the restriction and the ‘wash-off’ restriction. The restriction proposal about D4, D5, and D6 in leave-on products, also add D6 to the ‘wash-off’ restriction was published in March 2019.
After a Risk Management Option Analysis (RMOA) of D4 and D5 in late 2017, Germany make a conclusion that these substances conform to the REACH standard for PBT and vPvB and should be defined as Substances of Very High Concern (SVHC). Meanwhile the Commission requested ECHA to establish a similar SVHC archive for D6, according to the ECHA PBT Expert Group’s conclusion that D6 should be defined a vPvB substance.