SAN FRANCISCO (CBS SF) -- It's convenient and a staple in most kitchens, but a lot of canned food still contains an ingredient linked to birth defects and cancer.
Bisphenol-A or BPA has been removed from baby products, re-usable water bottles and most toys. But the chemical can still be found in a lot of food packaging.
The Center For Environmental Health recently tested more than 250 cans purchased at supermarkets and dollar stores
The tests found nearly 40 percent still contain BPA.
While that figure is down from 67 percent two years ago, it is still too high as far as health officials are concerned.
"It's still much too high," said Charles Margulis, a spokesperson for the Center For Environmental Health. "We need to get it down to zero."
BPA is used in can linings.
Some research has shown that BPA can seep into food or beverages from containers that are made with BPA.
The Food and Drug Administration says BPA is safe at the current levels occurring in foods.
However, California recently added BPA to its Prop 65 list as a chemical known to cause reproductive toxicity.
Margulis says there are other health concerns
"BPA is known to cause birth defects, and it's also linked to breast cancer, obesity and many other serious health problems," he said.
Margulis says even at low levels, BPA can be dangerous and those with low incomes may be most at risk.
The study found more than half the cans purchased at 99 Cents Only contained BPA.
"In many areas, Dollar Stores are the only places people can go for fruits and vegetables," said Margulis.
His advice is for consumers buy fresh fruits and vegetables and organic items when possible.
Beginning next year, cans that contain BPA will have to come with a Prop 65 warning label, but until then, you can opt for cans that are already labeled "BPA free."
State regulators say they hope the warning label requirements will eventually convince manufactures to phase out BPA cans.
BPA warning labels are currently required at the checkout register.
The supermarkets whose cans were tested for the study tell us they are working to eliminate BPA. in their cans.
The Dollar Store and 99 Cent Store did not immediately respond to our request for comment on the study.
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