All phosphates, including trisodium phosphate (TSP) are excessively damaging to the environment, particularly lakes and rivers. More than 19 states and several counties in 15 other states limit the phosphorous content of household laundry products to 0.5% (this is assumed to be a virtual ban). Skin, eye or respiratory contact with tri-sodium phosphate is hazardous. TSP also leaves a phosphate film on surfaces that if not thoroughly rinsed off will cause adhesion failure and/or blistering of new paint or encapsulant.
Phosphate mixed with lead can form a compound known as lead-phosphate. Any of the many slightly soluble lead compounds can react with phosphate in solution to form lead-phosphate which can precipitate out of solution as a residue. The Merck Index 11th edition states about lead-phosphate; “This substance may reasonably be anticipated to be a carcinogen.”