Materials, products and services - the Green Guide Online provides details of the life cycle environmental impacts of construction materials and components, and the Green Book is a free online database of products and services.
Spermicides are used globally for birth control, with or without condoms. As the only means of birth control, spermicides are rarely effective. However, in conjunction with condoms, spermicides are somewhat effective in birth control.
Copper ions prevent pregnancy by inhibiting the movement of sperm, because the copper-ion-containing fluids are directly toxic to sperm. Even if an aggressive little spermatozoa fertilizes an egg, the copper ion laden environment prevents implantation of the fertilized egg, and thus pregnancy. Advertisement.