Sewage sludge is the growing and continuous mountain of hazardous waste produced daily by wastewater treatment plants. The sewage sludge industry has created a PR euphemism it uses in place of the words "sewage sludge": "biosolids."
In March 2013, a study led by the University of North Carolina's Dr. Steve Wing involving neighbors of land where sewage sludge had been dumped -- "living in rural and semirural areas within approximately one mile of sewage sludge land application sites in North Carolina, South Carolina and Virginia" -- found that "over half of respondents attributed physical symptoms to application events." More specifically, "Over half (18/34) of the interview respondents associated acute physical symptoms that lasted a short period of time with sludge application events near their home (Table 1). The most commonly reported symptoms were eye, nose, and throat irritations and gastrointestinal symptoms (nausea, vomiting, diarrhea). Other symptoms reported by more than one respondent include cough, difficulty breathing, sinus congestion or drainage, and skin infections or sores."
The full epidemiological study can be found here.