Phthalate esters come from phthalic acid which is used in many different types of plastics. It has been around since the 1930's when PVC plastics were first introduced.  It's main purpose historically has been to make traditional thicker plastics like PVC thinner, more flexible, transparent and last longer. Thus these are the exact plastics that have been used to produce kiddie pools and inflatable pools. While it did this very effectively, the problem is that phthalates don't chemically bond to the PVC molecules when they are mixed in. Several mixing processes have been tried but no successful way to get them bonded has been found. Over time as the plastic gets older and starts to break down the phthalates separate and leach out into the air, water, or directly onto skin. This can lead to the phthalates being ingested later after they have entered the water table and environment. While low levels of phthalates are found in most people, studies have shown that mice exposed to high levels have had hormone changes and caused birth defects. Babies and small children often have the highest levels of phthalates because of their tendency to put things in their mouth. Also most kids toys and products are made of plastics that have these same phthalates in them. Once phthalates are in the body they eventually work their way out into urine and exit the body.

Plastic kiddie pools that kids love to play in particularly the inflatable ones for the backyard, are worrisome because they are outside in the sun and filled with water. Being out in the sun increases the rate at which the plastic degrades making phthalates leach out quicker. Even if you change the water in the inflatable pools every day, in the middle of the summer the sun is so intense that it within an hour phthalates are polluting it again. While some of these phthalates will disperse in the air filling the plastic inflatable pool with water provides a medium for it to suspend and concentrate in. Even if you change the water in the inflatable pools every day, in the middle of the summer the sun is so intense that it within an hour phthalates are polluting it again. This increases the exposure to your kids through accidental ingestion of the pool water and skin contact. When there are other alternatives out there why subject kids to these harmful chemicals?