food and water bowls are made of hard plastic, and your cat probably shows no ill effects. Some of the more persnickety cat fanciers claim that plastic bowls are wrong for cats: plastic cracks and erodes over time, and bacteria grow in the tiny crevices. Older plastic can become rough enough to irritate the cat’s skin.
And no matter how often a plastic bowl is cleaned, it can harbor odors. Ceramic is not a good option either, since some ceramic ware contains lead, which is poisonous (over a long period, anyway). So, say some of the experts, the only really safe choices are bowls of glass or stainless steel.