A lead service line (LSL, also known as lead service pipe, and lead connection pipe) is a pipe made of lead which is used in potable water distribution to connect a water main to a user's premises. Lead exposure is a public health hazard as it causes developmental effects in fetuses, infants, and young children. It also has other health effects in adults. According to World Health Organization, the presence of lead service lines is the most significant contributor of lead contamination in drinking water in many countries.