Do biosolids contain toxic pollutants?
A group of more than 100 pollutants are known to be potentially harmful to humans, animals and plants. EPA divides toxic pollutants into two primary categories: metals and organics. Biosolids can contain low concentrations of metals. As municipal wastewater treatment facilities and systems have improved during the last 20 years, metal concentrations in biosolids have decreased dramatically and typically are well below federal and state standards. Many of the trace metals in biosolids, including cadmium, lead, copper and zinc, can enter wastewater from industrial drains and metal pipes in homes and businesses. Some of these metals, known as micronutrients, are essential in small amounts for plant survival. Biosolids are routinely tested for metal concentrations to ensure compliance with state and federal regulations. Organic compounds, including pesticides, solvents and polychlorinated biphenyls (PCBs), can be present in biosolids in concentrations near the lowest detectable limits. Stu
Biosolids are routinely tested for metal concentrations to ensure compliance with state and national guidelines. These tests (for nine metals and nine pesticides and organo-chlorides) are based on extensive research and recommendations from the United States Environmental Protection Authority. As municipal wastewater treatment facilities and systems have improved during the past 20 years, metal concentrations in biosolids have decreased dramatically and typically are well below national and state guidelines. Many of the trace metals in biosolids, including cadmium, lead, copper and zinc, enter wastewater from industrial drains and metal pipes in homes and businesses. Some of these metals, known as micronutrients, are essential in small amounts for plant survival. Others such as cadmium, (which is a common ingredient of toothpaste), are monitored very closely in biosolids to ensure they remain well below the guideline accepted values. Organic compounds, including pesticides, solvents an
