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Don’t fancy the thought of your spinach and carrots being grown in sewage sludge?
Neither does Mario Ciasulli, a semi-retired electrical engineer living in Chapel Hill, North Carolina. Mario likes to cook, and enjoys good food. When he found out last year about the practice of spreading dried and heated human and industrial waste as “fertilizer” on food crops, he was upset.
But sometimes the vegetable Mario needs for a dish isn’t certified organic, or he can’t afford the higher price of the organically grown version. Until he found out about sludge, he thought that as long as a “conventionally” grown fruit or vegetable he used wasn’t one of the “dirty dozen” for pesticide residues, he had nothing to worry about.
Sewage sludge is created by all of the human waste flushed down the toilet and sinks — which includes all the pharmaceutical residues the men, women, and children in the city using the sewage system use — and all the material corporations flush down the drain, which can include industrial materials, solvents, medical waste, and other chemicals. The water is removed from the sludge, and it is heated to kill certain bacteria, but the heating of the sewage sludge does not remove metals, flame retardants (which California recently listed as a carcinogen, or cancer-causing agent), and other chemicals that remain in the sewage sludge when food crops are grown in it.
Toxic Sludge Yuck KidToxic Sludge Yuck KidIn addition to flame retardants and metals, sewage sludge has been shown to contain toxic substances and other contaminants such as endocrine disruptors, pharmaceutical residues, phthalates, industrial solvents, resistant pathogens, and perfluorinated compounds. Some of these contaminants can “bioaccumulate” in plants grown in sludge-contaminated soil and remain as residue on vegetables in contact with the soil. These plants are then eaten by children and adults.