Among the substances found in milk were skimmed milk powder, fat, glucose and added water.
In urban India, 68.9 percent of samples were found to be contaminated, compared with 31 percent of samples in rural areas.
Only two states -- Goa and Pondicherry -- sold unadulterated milk, while all 250 samples from four eastern states were found to be contaminated with detergent.
Fat and non-edible solids were the top offenders nationwide, followed by skimmed milk powder. Detergent was found in 8.4 percent of all samples.
Despite being the world's biggest milk producer, India is no stranger to adulterated milk.
"Addition of water not only reduces the nutritional value of milk but contaminated water may also pose health risks," the study said, adding that the presence of detergent "indicates lack of hygiene and sanitation in the milk handling."
In November 2008, six tribal children died and dozens were hospitalised after drinking milk provided to their school by a dairy in eastern India. State officials blamed the deaths on adulterated milk.
Source: AFP