I am attaching the link to the whole article at the end of the copied paragraph.
I have heard for years ceremic bowls mostly because of the glaze and paint contains lead etc. and have posted this warning a few times to people in emails etc. - Here is a good summary of this ..
" Plastic Bowls- Painted Ceramic Bowls always put water in STAINLESS STEEL or CLEAR GLASS BOWLS, Not plastic or ceramic! Plastic deteriorates no matter how often you clean or change water. Research shows that when plastic containers, such as cups and dishes are filled with water or other liquids that they will gradually dissolve. This could be hazardous to your pet's health. (from Dr. Michael Fox's column in the NY post) Email questions to [email protected] . Painted Ceramic Bowls even if glazed could still lead to lead in your pets food or water. This is a tip for PEOPLE TOO! Only use WHITE or clear glass. Never 'colors'! If the OUTSIDE of the bowl is color it's fine but not the INSIDE. Even if 'glazed' the lead or toxins from paint and colors can get into the food and water" .
Here is a good link on general other poisons to dogs.. http://www.treshanley.com/cic/hazards.html
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