Are the laundry detergents safe for greywater and septic systems? April 11, 2017 13:05 Updated All Seventh Generation Laundry Detergent formulas are safe for both greywater systems and septic systems. Related articles Can Seventh Generation laundry detergents be used in any water temperature? High-Efficiency (HE) Laundry Detergents Do Seventh Generation Automatic Dishwashing products contain phosphates? Will Seventh Generation laundry detergent remove perspiration stains? Is Seventh Generation Laundry Detergent safe for cloth diapers?