Dioxins in Sewage Sludge
Dioxins refers to a group of chemical compounds that share certain chemical structures and biological characteristics. Several hundred of these chemicals exist and are members of three closely related families 1) chlorinated dibenzo-p-dioxins (CDDs); 2) chlorinated dibenzofurans (CDFs); and 3) certain polychlorinated biphenyls (PCBs). CDDs and CDFs are not created intentionally but are produced as a result of human activities like the backyard burning of trash. Natural processes like forest fires also produce CDDs and CDFs. PCBs are manufactured products, but they are no longer produced in the United States.
Some industrial activities may deposit dioxins in water that is subsequently treated at wastewater treatment plants (WWTPs). Through the treatment process as water is cleaned and returned to bodies of water, the dioxins may remain in the biosolids.
2001 National Sewage Sludge Survey
Dioxins refers to a group of chemical compounds that share certain chemical structures and biological characteristics. Several hundred of these chemicals exist and are members of three closely related families 1) chlorinated dibenzo-p-dioxins (CDDs); 2) chlorinated dibenzofurans (CDFs); and 3) certain polychlorinated biphenyls (PCBs). CDDs and CDFs are not created intentionally but are produced as a result of human activities like the backyard burning of trash. Natural processes like forest fires also produce CDDs and CDFs. PCBs are manufactured products, but they are no longer produced in the United States.
Some industrial activities may deposit dioxins in water that is subsequently treated at wastewater treatment plants (WWTPs). Through the treatment process as water is cleaned and returned to bodies of water, the dioxins may remain in the biosolids.
Decisions Not to Regulate Dioxins in Sewage Sludge
In 2001, EPA published its determination that standards or management practices are not warranted for dioxin and dioxin-like compounds in sewage sludge that has been disposed of at a surface disposal site or incinerated in a sewage sludge incinerator. In 2003, EPA published its decision not to regulate dioxins in land-applied sewage sludge.