Any kind of bottle or container, whether glass, plastic or aluminium, pollutes the environment to manufacture it, fill it and transport it to the shops. A tap sits there behaving itself and you turn it on to get water. I've visited our local water-treatment plant, and it all seems very reassuring to me. I feel one can get too paranoid about what's in our food/water. You can't go through life chewing your fingernails about these things. As long as it's all reasonably okay, eat drink and be merry! (Life is short, relax!)