This is in response to an article by Casella Organics that appeared in a Sun Journal special insert, “Water 2013,” May 26. The article, “Close the Loop on Wastewater Treatment Process with Biosolids,” misinformed readers about what biosolids are and what happens when they are land-applied.

Urban sewage contains not only nitrogen and phosphorus, but also a vast array of industrial pollutants — some highly toxic and persistent — that end up in the food chain. Every industry, super-fund site, metal plating shop, hospital, business, dry cleaning establishment — in fact, every entity connected to a sewage treatment plant — can annually discharge any amount of hazardous and acute hazardous waste into sewers after complying with the one-time notification requirement during the first calendar month.

Treatment plants are designed to remove the hazardous waste, mixed with other unregulated contaminants, from the wastewater. The removed pollutants concentrate in the resulting biosolids. No amount of processing, digesting or dewatering will destroy these pollutants.

The EPA recently sampled biosolids from 74 facilities and found priority pollutants in every sample. Moreover, several recent studies have shown that sewage treatment plants are breeding grounds for super bugs which also end up in biosolids. Even Class A Exceptional Quality sludge can legally contain 41 mg/kg of arsenic, 39mg/kg of cadmium, 17 mg/kg of mercury, and 300 mg/kg of lead.

Fifteen years ago, internationally renowned soil scientists at the Cornell Waste Management Institute warned that the 503 sludge rule does not protect human health, agriculture or the environment. Five years later, a National Academy of Sciences panel also concluded that the current regulations are based on outdated science and recommended major rule changes. None of the recommended changes have been implemented.

Hundreds of sludge-exposed citizens have reported serious, even life-threatening and chronic dermal, gastro-intestinal, and respiratory ailments.

In 2002, microbiologist David Lewis, then a high ranking EPA scientist, published ground-breaking research that linked illnesses and several deaths to biosolids exposure.

In Augusta, Ga., two prize-winning dairy herds were destroyed after animals ingested sludge-contaminated forage. Maine scientists monitoring ground water at several sites where biosolids had been stockpiled or used to reclaim spent sand and gravel pits, found high levels of nitrogen, arsenic and manganese.

Every environmental group, including the Sierra Club, opposes using biosolids to grow food. Major food processors, such as Heinz and Del Monte, will not accept produce grown on land treated with biosolids.

Processed sewage sludge is probably the most pollutant-rich material created in the 21st century. Using it as “fertilizer” has nothing to do with “closing a loop.”

The nation’s industrial waste does not belong on the land were we grow our food and graze our animals.

Caroline Snyder, North Sandwich, N.H.