For many polyethylene products, their working life-span depends on retention by the material of its antioxidant. In dry air, when the working and environmental stresses remain within defined limits, the life-span of the material can be many decades. Immersed in water, for example, the diffusion and loss of antioxidant from the material's surface can increase. Also, some types of aggressive agents, if in the water, can enter the material's surface and migrate into the material to increase the depletion of the antioxidant population. Researched in this study, is the depletion of antioxidants in polyethylene when exposed to water containing different chlorine concentrations. This research relates to the world-wide use of polyethylene pipes in water treatment and distribution networks.