SALT LAKE CITY — A local consumer science expert is urging cooks to exercise caution when using glass baking dishes after a national investigation by Consumer Reports that revealed the glassware can shatter unexpectedly — sometimes causing serious injuries.
Consumer Reports analyzed federal documents, court records and conducted interviews regarding 163 incidents of shattering bakeware. Forty-two of the incidents resulted in injuries, ranging from burns to cuts that required surgery.
More than half of the incidents occurred while the bakeware was in the oven, although nearly a quarter occurred while the bakeware was cooling on a counter or stovetop, the consumer publication reported.
Marilyn K. Albertson, associate professor of family and consumer science for Utah State University, said it is important to follow manufacturers' instructions when using the popular bakeware. The leading manufacturers, Anchor Hocking and World Kitchen, the maker of Pyrex, make more than 70 million units of the baking dishes each year.
"I know I have some, and I really enjoy using them," Albertson said. "I try to be very cautious in my behavior when I go to use it, because of the warnings I have seen."
When using glass baking dishes, an oven should be preheated.
Hot glassware should be placed on a dry, cloth potholder or cooling rack, Albertson said. It should never be placed directly on a countertop, metal surface, on a damp towel, in the sink or on a cold or wet surface, Consumer Reports advises.
Liquids should be added to meat or vegetables prior to cooking. Consumer Reports reported that a glass baking dish containing a Thanksgiving ham shattered, sending pieces of glass and hot juice flying when a woman attempted to baste the meat.
Glass baking dishes should never be placed directly on a stove burner or under a broiler.
Dishes should not be taken directly from the freezer to the oven or vice versa.
In recent years, leading manufacturers of glass bakeware have changed "ingredients," Albertson explained. Previously, the products were made of a glass called borosilicate. Now, the leading manufacturers use soda lime glass. It is not as expensive to produce and less likely to break if dropped or bumped.
When researchers compared the two types of glassware (European manufacturers still use borosilicate), they determined that borosilicate held up better under extreme heat.
Albertson said glass bakeware is safe to use if consumers follow manufacturers' instructions. "There may not be any type of extensive labeling on the items, so you would want to be aware of those things when you make a purchase," she said. Consumer Reports editors wrote that fine-print warnings have been tiny and that they are printed on packaging that consumers often discard.
The cookware is popular because it can be used in microwave ovens as well as conventional ovens. "Plus, they look nice on the table."
Consumers who want to avoid the possibility of shattering glass can use metal pans in their conventional ovens.
If consumers follow commonsense rules, they can use glass bakeware safely, Albertson said.
"I think it's 'consumer beware.' "
e-mail: marjorie@desnews.com